O iginal Resea ch A icle
Pos na al G ow h Veloci y and O e weigh in Ea ly Adolescen s: A Compa ison
o Ru al and U ban A ican Boys and Gi ls
E.D. CHIRWA,
1
* P. GRIFFITHS,
1,2
K. MALETA,
3
P. ASHORN,
4
J.M. PETTIFOR,
1
AND S.A. NORRIS
1
1
Wi s/MRC De elopmen al Pa hways o Heal h Resea ch Uni , Depa men o Pedia ics, Facul y o Heal h Sciences, Uni e si y o he
Wi wa e s and, Johannesbu g, Sou h A ica
2
Cen e o Global Heal h and Human De elopmen , Loughbo ough Uni e si y, Loughbo ough, Leices e shi e, LE 11 3TU, Uni ed Kingdom
3
Depa men o Communi y Heal h, College o Medicine, Uni e si y o Malawi, Malawi
4
Depa men o In e na ional Heal h, School o Medicine, Uni e si y o Tampe e, Finland and Depa men o Pedia ics, Tampe e Uni e si y
Hospi al, Finland
Objec i es: To compa e g ow h eloci y o wo A ican child coho s and examine he ela ionship be ween pos na al
g ow h eloci y in in ancy/ea ly childhood and he isk o o e weigh /s un ing in ea ly adolescence.
Me hods: The s udy used da a om wo child coho s om u ban (Bi h o Twen y Coho , Sou h A ica) and u al
(Lungwena Child Su i al S udy, Malawi) A ican se ings. Mixed e ec modelling was used o de i e g ow h and peak
g ow h eloci ies. T- es s we e used o compa e g ow h pa ame e s and eloci ies be ween he wo coho s. Linea and
logis ic eg ession models we e used o de e mine he ela ionship be ween g ow h eloci y and ea ly adolescen (ages
9–11 yea s) body mass index and odds o being o e weigh .
Resul s: Child en in he BH coho we e signi ican ly alle and hea ie han hose in he Lungwena coho , and
exhibi ed as e weigh and heigh g ow h eloci y especially in he i s yea o li e (P<0.05). No signi ican associa-
ion was shown be ween baseline weigh (a
w
) and o e weigh in ea ly adolescence (OR 51.25, CI 50.67, 2.34). The
weigh g ow h eloci y pa ame e b
w
was highly associa ed wi h odds o being o e weigh . Associa ion be ween o e -
weigh in adolescence and weigh eloci y was s onge in in ancy han in ea ly childhood (OR a 3 mon hs 54.80,
CI 52.49, 9.26; OR a 5 yea s 52.39, CI 51.65, 3.47).
Conclusion: High weigh and heigh g ow h eloci y in in ancy, independen o size a bi h, is highly associa ed
wi h o e weigh in ea ly adolescence. Howe e , he long e m e ec s o apid g ow h in in ancy may be dependen on a
pa icula popula ion’s socio-economic s a us and le el o u baniza ion. Am. J. Hum. Biol. 26:643–651, 2014. V
C2014
The Au ho s Ame ican Jou nal o Human Biology Published by Wiley Pe iodicals, Inc.
Se e al s udies ha e shown he associa ion be ween
ea ly childhood g ow h and la e heal h ou comes such as
diabe es, ca dio ascula diseases, and obesi y (Came on
and Deme a h, 2002; Came on e al., 2003; Adai , 2007;
Adai e al., 2009). In pa icula , s udies ha e examined
he c i ical pe iods in in ancy and ea ly childhood ha a e
associa ed wi h hese heal h ou comes (Black and K ish-
nakuma , 1999; McCa hy e al., 2007; Bo on e al., 2008;
Ridgway e al., 2009).
Bo h g ow h e a da ion and apid g ow h in he di e -
en s ages o ea ly li e a e p edic i e o he la e heal h ou -
comes (Came on and Deme a h, 2002; Li, 2003; Came on
e al., 2005; S ein e al., 2010). Fo example, Flexede e al.
(2012) ound ha apid weigh gain in in ancy is associa ed
wi h physician-diagnosed as hma in school-aged child en
(Flexede e al., 2012). A numbe o s udies ha e examined
he ela ionship be ween ea ly g ow h and la e heal h
ou comes in high income as well as low and middle income
coun ies (LMIC; Ma o ell, 1995; Ong e al., 2000; Li,
2003; Salonen e al., 2009; Mesa e al., 2010; S ein e al.,
2010). Howe e , he e ha e also been inconsis en indings
ega ding he ela ionship be ween g ow h e a da ion, o
s un ing and o e weigh and obesi y in la e li e. Whe eas,
i has been sugges ed ha childhood unde -nu i ion p e-
disposes a child o weigh gain in la e li e (Ho man e al.,
2000), o he s udies ha e ound ha childhood s un ing
was associa ed wi h lowe body mass index (BMI;
Sch oede e al., 1999; Walke e al., 2007).
Se e al s udies ha e also shown he sho e m and
long e m bene i s o apid g ow h o child en in
esou ce-poo se ings (Vic o a e al., 2001; Kalanda e al.,
2005; Hoddino e al., 2008; Vic o a e al., 2008). The
sho e m bene i s include, educed mo bidi y and mo -
ali y, and imp o ed cogni i e de elopmen , while long
e m bene i s include imp o ed human capi al and
imp o ed ep oduc i e ou comes in women.
Al hough a wide body o e idence suppo s he long
e m bene i s and de imen al e ec s o ea ly apid
g ow h in LMIC, ew s udies ha e looked a his ela ion-
ship in a sub-Saha an A ican con ex , due o he limi ed
numbe o bi h coho s udies. Thus, his s udy compa ed
he g ow h eloci ies o wo coho s om u al and u ban
A ican se ings, and examined he ela ionship be ween
size a bi h (bi h weigh ), g ow h eloci y in in ancy and
This is an open access a icle unde he e ms o he C ea i e Commons
A ibu ion License, which pe mi s use, dis ibu ion and ep oduc ion in
any medium, p o ided he o iginal wo k is p ope ly ci ed.
Con ac g an sponso s: Conso ium o Ad anced Resea ch T aining
in A ica (CARTA) which is—join ly led by he A ican Popula ion and
Heal h Resea ch Cen e and he Uni e si y o he Wi wa e s and and
unded by he Welcome T us (UK); Con ac g an numbe : 087547/Z/08/
Z; Depa men o In e na ional De elopmen (D ID) unde he De elop-
men Pa ne ships in Highe Educa ion (DelPHE); he Ca ne gie Co po a-
ion o New Yo k; Con ac g an numbe : B 8606; Fo d Founda ion;
Con ac g an numbe : 1100-0399; Google.O g; Con ac g an numbe :
191994; SIDA; Con ac g an numbe : 54100029; MacA hu Founda ion;
Con ac g an numbe : 10-95915-000-INP.
*Co espondence o: Esna D. Chi wa, MRC/Wi s De elopmen al Pa h-
ways o Heal h Resea ch Uni , Facul y o Heal h Sciences, Uni e si y o
he Wi wa e s and, 7 Yo k Road, Pa k own 2193, Johannesbu g, Sou h
A ica. E-mail: Esna .Chi[email p o ec ed]
Recei ed 31 Oc obe 2013; Re ision ecei ed 30 Ap il 2014; Accep ed 28
May 2014
DOI: 10.1002/ajhb.22575
Published online 20 June 2014 in Wiley Online Lib a y
(wileyonlinelib a y.com).
V
C2014 The Au ho s Ame ican Jou nal o Human Biology Published by Wiley Pe iodicals, Inc.
AMERICAN JOURNAL OF HUMAN BIOLOGY 26:643–651 (2014)
ea ly childhood, and ea ly adolescen obesi y. The wo
coho s a e likely o be a di e en s ages o nu i ional
ansi ion, conside ing he u al coho is om a e y low
income coun y while he u ban coho is om a middle
income coun y. U baniza ion is gene ally linked o
changes in li es yle ac o s ha a ec obesi y isk, such as
die a y pa e ns and seden a y beha io s. Thus, apa
om he nu i ional di e ences, he e may also be social,
cul u al, economic and en i onmen al di e ences
be ween he wo coho s ha may a ec g ow h and
de elopmen o he child en and also a ec hei isk o
obesi y.
Mixed-e ec s modelling and childhood s uc u al
g ow h model we e used o examine he ela ionship
be ween pos na al g ow h eloci y and obesi y o s un ing
in ea ly adolescence (ages 9–11 yea s). Mixed-e ec s mod-
elling is lexible in dealing wi h unbalanced longi udinal
measu emen s, and akes in o accoun co ela ions
be ween epea ed measu emen s. The use o he s uc-
u al g ow h cu e allowed o he es ima ion o he
g ow h a es a any gi en age.
SUBJECTS AND METHODS
Weigh and heigh measu emen s om 2 A ican longi-
udinal coho s we e used. The Bone-Heal h (BH) S udy
is a sub-sample o he Bi h- o-Twen y (BH) bi h coho
in Johannesbu g, Sou h A ica, which includes 453 black
pa icipan s. The coho has an h opome ic measu e-
men s a bi h, 3 mon hs, 6 mon hs, 1 yea , 2 yea s, 4
yea s, 5 yea s, 7/8 yea s, 9 yea s, and 10 yea s. Bi h
weigh s we e ex ac ed om bi h eco ds, while subse-
quen weigh /heigh measu emen s we e ob ained using
s anda d an h opome ic echniques (Came on, 1984).
Mo e speci ic de ails abou his u ban coho a e epo ed
elsewhe e (Came on e al., 2003; Came on e al., 2005).
The u al componen o he s udy used he Lungwena
Child Su i al S udy (LCSS), which is a coho o abou
729 child en li ing in Mangochi, a u al dis ic in sou h-
e n Malawi. The on-going s udy has g ow h da a o chil-
d en om bi h o 16 o 17 yea s o age. The
an h opome ic da a in his coho we e collec ed mon hly
om bi h un il 18 mon hs, 3 mon hly un il 60 mon hs,
hen a 6 yea s, 8–9 yea s, 10 yea s, 12 yea s, and 15
yea s. Weigh and heigh we e measu ed du ing home
isi s, using po able sp ing-scales and sel -made leng h
boa ds, ha ing eading inc emen s o 100 g and 5 mm,
espec i ely. Mo e speci ic de ails o he Lungwena
coho a e epo ed elsewhe e (Espo e al., 2002; Male a
e al., 2003).
In bo h coho s, g ow h eloci ies we e de i ed om a
s uc u al g ow h model i ed o g ow h da a om bi h
o 60 mon hs. The exclusion c i e ia and he o e all num-
be o pa icipan s a ailable o analysis a e shown in
Figu e 1.
Because o di e ences in he socio-economic s a us
(SES) a iables collec ed in he wo coho s, an SES sco e
was calcula ed sepa a ely o each coho . The SES a ia-
bles in he BH coho included household asse s such as
ca , TV, idge and washing machine, and household acili-
ies such as ype o wa e sys em, oile ype and elec ic-
i y. The SES a iables o he Lungwena coho included
owne ship o land, a m animals, bicycle, and adio,
amongs o he s and household a iables such as ma e nal
and pa e nal li e acy le el. In each coho , an asse sco e
was ini ially de i ed based on household asse s. P incipal
componen analysis was hen used o de i e an o e all
SES sco e by combining he asse sco e wi h o he house-
hold and communi y SES a iables.
Fig. 1. Flowcha o he samples a ailable o analysis om he wo coho s.
644 E.D. CHIRWA ET AL.
Ame ican Jou nal o Human Biology
A Be key-Reed i s o de model (Be key, 1982) was i -
ed using mixed e ec s modelling. The model has he
unc ional o m;
y5a1b 1cln ðÞ1d= :
whe e y5weigh o heigh o child a age , he unc ion
pa ame e ais ela ed o he baseline weigh o heigh a
bi h, bis ela ed o he linea componen o he g ow h
eloci y, cis ela ed o he decele a ion in g ow h eloci y
and d ep esen s an in lec ion poin ha allows g ow h
eloci y o peak a e bi h a he han a bi h (Mook-
Kanamo i e al., 2011).
The model was modi ied as sugges ed by Simondon
e al. (1992), so ha i is de ined a bi h ( 50) as ollows:
y5a1b 1cln 11ðÞ1d=ð 11Þ:
P e ious analyses ha e shown his model o ha e op i-
mum i o he BH coho g ow h da a (Chi wa e al.,
2014). The model was used o desc ibe g ow h pa e ns in
ea ly childhood a e adjus ing o ma e nal cha ac e is-
ics (ma e nal heigh and age), SES and ges a ional age.
Sepa a e models we e i ed o boys and gi ls in each
coho . The i s o de de i a i e o he model was hen
used o de i e weigh and heigh eloci ies o e ime (Bo -
on e al., 2008; Mook-Kanamo i e al., 2011). The g ow h
eloci y unc ion was hen used o de i e he peak weigh
eloci y (PWV), peak heigh eloci y (PHV) and he age a
which a child eached i s PWV (APWV) and i s peak
heigh eloci y (APHV). The p ima y ou comes we e BMI
and he p opo ion o child en who we e o e weigh in he
9–11 yea age g oup. BMI cu -o cha s o child en we e
used o calcula e co esponding o e weigh cu -o s (Cole
e al., 2000, 2007).
The de i ed pa ame e es ima es, g ow h eloci y,
in an peak eloci y and he age a peak eloci y we e
used as p edic o s o adolescen BMI o obesi y. T- es s
we e used o compa e weigh , heigh g ow h eloci y,
peak g ow h eloci y be ween boys and gi ls wi hin and
be ween coho s. Linea eg ession was used o examine
he ela ionship be ween BMI- o -age z-sco es (BMIZ) in
la e childhood and ea ly adolescence (9–11 yea s) and p e-
dic o s, adjus ing o bi h weigh , sex and coho di e -
ences. Logis ic eg ession was hen used o explo e
p edic o s o obesi y, adjus ing o coho di e ences and
bi h weigh . Analysis was done using S a a Ve sion 11,
and all s a is ical es s we e pe o med a 5% signi icance
le el.
The BH s udy was app o ed by he Human Resea ch
E hics Commi ee o he Uni e si y o Wi wa e s and,
while he LCSS was app o ed by he Malawi Na ional
Heal h Science Resea ch Commi ee.
RESULTS
Desc ip i e s a is ics
The p opo ion o boys in he BH coho was highe
han ha o gi ls (57% s. 43%), while he p opo ion o
boys and gi ls in he Lungwena coho was almos he
same (51% s. 49%). O he 216 child en in he BH coho ,
almos hal we e i s bo n, while only 19% o he 341 chil-
d en om he Lungwena coho we e i s bo n. The a e -
age ma e nal age o he BH coho was 25 yea s (wi h
s anda d de ia ion (SD) o 5.9), while he a e age age in
he Lungwena coho was 26 yea s (SD 56.5). BH coho
mo he s we e on a e age alle han hei Lungwena
coun e pa s (158 cm s. 155 cm).
Table 1 shows he mean an h opome ic measu emen s
in in ancy/ea ly childhood and la e childhood/ea ly adoles-
cence be ween boys and gi ls in he wo coho s. The e
we e no signi ican di e ences in he a e age size a bi h
be ween he coho s (P>0.05). Howe e , BH boys and
gi ls expe ienced mo e apid weigh gain om 3 mon hs
TABLE 1. Compa ison o physical g ow h measu emen s be ween boys and gi ls in he wo coho s
NBoys Gi ls nBoys Gi ls Sig
1
Sig
2
Bi h and ea ly childhood
Weigh (kg)
Bi h weigh 216 3.2 60.5 3.1 60.4 341 3.3 60.5 3.2 60.5 0.115 0.070
3 mon hs 82 6.5 60.8 5.8 60.7 274 6.0 60.8 5.5 60.7 <0.001 <0.001
6 mon hs 52 8.1 60.9 7.4 61.0 286 7.2 61.0 6.6 60.9 0.011 <0.001
1 yea 193 9.7 61.4 9.2 61.3 302 8.4 61.1 8.0 61.1 0.012 0.002
2 yea 153 11.8 61.7 11.4 61.4 308 10.5 61.4 10.1 61.3 0.126 0.010
4 yea 210 15.5 61.9 14.9 61.8 326 14.6 61.5 14.0 61.6 0.021 <0.001
5 yea 187 18.6 62.0 17.9 62.1 338 16.0 61.8 15.5 61.9 0.022 0.016
Heigh (cm)
Bi h leng h – – – 341 48.9 62.2 47.9 62.1 - <0.001
3 mon hs 82 60.8 62.9 58.7 62.8 274 57.3 62.4 56.1 62.6 0.001 <0.001
6 mon hs 52 66.3 62.8 63.4 64.1 286 62.5 62.6 60.6 62.6 0.015 <0.001
1 yea 187 74.4 63.1 72.6 63.0 302 69.0 62.6 67.8 62.6 <0.001 <0.001
2 yea s 143 83.6 63.7 82.2 63.1 308 78.2 63.7 76.9 63.4 0.010 0.002
4 yea s 210 99.2 63.9 97.9 63.9 326 93.9 64.3 92.4 64.4 0.017 0.002
5 yea s 187 108.8 64.0 107.4 64.2 338 100.9 64.4 99.4 64.7 0.022 0.003
Ea ly adolescence
Age (yea s) 216 10.5 60.3 10.5 60.3 341 10.3 60.3 10.3560.3 <0.001 0.011
Heigh (cm) 216 137.8 66.1 138.4 65.9 341 129.765.5 128.46 66.0 <0.001 <0.001
Weigh (kg) 216 32.966.2 33.4 66.6 341 25.7 63.2 25.22 63.5 <0.001 <0.001
BMI (kg/m
2
) 216 17.362.5 17.4 62.9 341 15.3 61.2 15.22 61.2 <0.001 <0.001
O e weigh (%) 26(21%) 22(24%) 2(1.2%) 0(0%) <0.001 <0.001
Unde weigh (%) 1(0%) 5(5%) 13(8) 17(10%) <0.001 0.246
Sig
1
: BH boys s. Lungwena boys. All mean compa isons done using - es .
Sig
2
: BH gi ls s. Lungwena gi ls. All p opo ions compa isons done using Fishe s’ exac es .
POSTNATAL GROWTH AND OBESITY IN EARLY ADOLESCENTS 645
Ame ican Jou nal o Human Biology
onwa ds as shown by he signi ican di e ences in mean
weigh om 3 mon hs, wi h BH boys and gi ls weighing
on a e age mo e han hei Lungwena coun e pa s.
Al hough he e we e no da a on bi h leng h o he BH
coho , subsequen measu emen s showed BH boys and
gi ls we e on a e age signi ican ly alle han hei Lung-
wena coun e pa s.
In ea ly adolescence, he e we e no signi ican di e en-
ces in weigh , age, heigh o BMI be ween boys and gi ls
wi hin each coho , bu he e we e signi ican di e ences
be ween he coho s, wi h BH boys and gi ls ha ing
highe mean BMI, heigh and weigh compa ed o he
Lungwena boys and gi ls. Howe e , unlike he pa e n in
in ancy/ea ly childhood, gi ls in he BH coho we e on
a e age alle and weighed mo e han boys a ages 9/10
yea s. Figu e 1 shows he dis ibu ion o BMI o boys and
gi ls in he wo coho s, wi h BH child en ha ing la gely
highe BMI han Lungwena child en. Howe e , he e is
also wide a ia ion in he BMI alues in he BH coho
(Fig. 2).
A e age model pa ame e and g ow h eloci y es ima es
Pa ame e es ima es o weigh and heigh models we e
de i ed o each child using he andom componen s o he
mixed models. A - es compa ison o hese pa ame e es i-
ma es showed signi ican di e ences in he a e age pa am-
e e es ima es be ween BH boys and Lungwena boys o
bo h he heigh and weigh g ow h model (Table 2). Simila
esul s we e also ound amongs he gi ls om he wo
coho s. BH boys had he highes s a ing alues (a
w
and
a
h
), as well as he highes linea g ow h a es (b
w
and b
h
).
Howe e he a
h
o he heigh model o bo h coho s ep e-
sen s s a ing heigh /leng h a 3 mon hs, due o he BH
coho no ha ing heigh /leng h measu emen s a bi h.
Wi hin each coho , he e gene ally we e no signi ican di -
e ences in model pa ame e es ima es be ween boys and
gi ls in bo h coho excep o b
w
and b
h
in he Lungwena
coho . Non-signi ican di e ence in he linea componen
o he eloci y cu e be ween boys and gi ls in he
Lungwena coho was also shown by he non-signi ican
di e ences in bo h weigh and heigh eloci ies. The e
we e signi ican di e ences in he weigh eloci y be ween
boys and gi ls in he BH coho excep a 24 mon hs.
Al hough boys in he Lungwena coho ended o ha e
highe weigh eloci ies han gi ls, he e we e no signi i-
can di e ences in a e age weigh eloci y be ween boys
and gi ls in he Lungwena coho om 12 mon hs onwa ds.
Boys in he BH coho gene ally exhibi ed highe heigh
eloci ies han gi ls, wi h signi ican di e ences in he
a e age heigh eloci y be ween boys and gi ls in he i s
2 yea s o li e (P<0.001).
As expec ed and consis en wi h he changes in a e age
weigh and heigh o e ime, as shown in Table 1, weigh
and heigh eloci ies we e highes in he i s 12 mon hs,
wi h g ow h a es apidly declining om 12 mon hs
(Table 2). The e we e no signi ican di e ences in he
a e age weigh eloci ies be ween small o ges a ional
age in an s (WAZ a bi h <22) and app op ia e o ges a-
ional age (AGA) in an s (da a no shown). Simila esul s
we e ound when compa ing hose wi h low bi h weigh
(bi h weigh <2.5 kg) o hose wi h no mal bi h weigh
(da a no shown).
The signi ican di e ences in he pa ame e es ima es
be ween BH boys and Lungwena boys as well as be ween
gi ls in he wo coho s, we e also shown by he signi ican
di e ences in he weigh and heigh eloci ies be ween
he coho s, wi h he BH boys ha ing highe g ow h a es
han hei Lungwena coun e pa s. Simila ly, BH gi ls
exhibi ed highe g ow h a es han Lungwena gi ls. A
s ong posi i e linea ela ionship be ween weigh and
heigh eloci y ( 50.89, P<0.001) was obse ed.
BH gi ls had he highes in ancy PWV (1.39 kg/mon h).
Howe e , no signi ican di e ence was obse ed in he
Fig. 2. BMI in ea ly adolescence o boys and gi ls in he wo coho s.
646 E.D. CHIRWA ET AL.
Ame ican Jou nal o Human Biology
in ancy PWV o PHV be ween sexes wi hin he Lungwena
coho o as well as be ween gi ls in he wo coho s. BH
boys which had he smalles PWV also had he younges
age a APWV. BH boy’s heigh eloci y also peaked ea -
lies compa ed o he o he h ee g oups.
Rela ionship be ween bi h weigh , g ow h eloci y, peak
eloci y and adolescen BMI
The e we e no signi ican co ela ions be ween bi h
weigh and weigh eloci y ( 520.08, P50.06) o heigh
eloci y ( 520.05, P50.27).
The e was a posi i e bu weak ela ionship be ween
bi h weigh and adolescen BMI, wi h bi h weigh only
explaining 1% o he a ia ion in BMI (Table 3). This ela-
ionship did no change e en a e adjus ing o sex di e -
ences. Howe e , when coho di e ences we e aken in o
accoun , he o al a ia ion explained by he model
inc eased om 1% o 24%, signi ying he la ge di e ences
ha exis be ween he wo coho s. The e ec o bi h
weigh on BMI was also suppo ed by he esul s om he
ela ionship be ween a
w
o he weigh model and BMI,
wi h no signi ican sex di e ence being obse ed. Wi hin
each o he h ee models using pa ame e es ima es om
weigh models, b
w
had he s onges linea ela ionship
wi h BMI compa ed o he o he h ee pa ame e es i-
ma es, wi h no linea ela ionship being obse ed
be ween adolescen BMIZ and d
w
. Bo h c
w
and d
w
we e
non-signi ican when e ec o coho and sex di e ences
as well as bi h weigh , we e aken in o accoun .
The e was a nega i e linea ela ionship be ween adoles-
cen BMIZ and APWV, indica ing ha in an s ha eached
hei PWV ea ly we e mo e likely o ha e high BMI in ado-
lescence. A s ong nega i e co ela ion was also obse ed
be ween PWV and APWV ( 520.53, P<0.001), indica ing
ha in an s wi h low PWV we e mo e likely o each hei
peak la e han in an s ha exhibi ed high PWV. The e
was no signi ican linea ela ionship be ween adolescen
BMIZ and age a which he in an eached PHV.
The e was a gene al dec ease in he ela ionship be ween
weigh eloci y and adolescen BMIZ o e ime e en a e
adjus ing o bi h weigh (R
2(3m)
50.38, R
2(60m)
50.29).
E en hough he e was a s ong ela ionship be ween
adolescen BMIZ and heigh eloci y in he i s 6 mon hs,
e en a e adjus ing o bi h weigh , as obse ed om
he R
2
alues (models 1 and 2), he e we e no di e ences
in he s eng h o he ela ionship o e ime when coho
and sex di e ences we e aken in o accoun (model 3).
TABLE 2. A e age di e ences in pa ame e es ima es, g ow h eloci y and peak eloci y be ween coho and sex
BH coho Lungwena coho Coh. di . Sex di .
Boys Gi ls Boys Gi ls M F BH LUN
Mean (SD) Mean (SD) Mean (SD) Mean (SD) sig sig sig Sig
Pa ame e s (weigh )
a
w
6.70 (0.45) 4.44 (0.34) 5.49 (0.66) 5.13 (0.63)
aaaa
b
w
0.16 (0.02) 0.13 (0.03) 0.14 (0.02) 0.14 (0.03)
a
0.023
a
0.816
c
w
0.42 (0.02) 1.16 (0.03) 0.54 (0.02) 0.48 (0.03)
aaaa
d
w
23.50 (0.03) 21.36 (0.03) 22.68 (0.03) 22.43 (0.03)
aaaa
Pa ame e s (heigh )
a
h
66.5 (2.07) 56.4 (1.95) 54.1 (2.28) 53.5(2.20)
aaa
0.030
b
h
0.59 (0.04) 0.52 (0.06) 0.52 (0.06) 0.52 (0.07)
a
0.815
a
0.654
c
h
1.37 (0.03) 4.42 (0.06) 3.79 (0.07) 3.56 (0.08)
aaaa
d
h
239.8 (0.04) 222.6 (0.05) 215.3 (0.06) 216.8 (0.08)
aaaa
Peak eloci y
PWV 1.31 (0.26) 1.39 (0.28) 1.36 (0.24) 1.35 (0.29) 0.067 0.217 0.024 0.579
APWV (mon hs) 2.49 (0.02) 2.86 (0.05) 3.10 (0.06) 2.96 (0.07)
aaaa
PHV 5.77 (0.37) 5.59(0.58) 5.51 (0.67) 5.53 (0.84)
a
0.556 0.006 0.882
APHV (mon hs) 5.00 (0.08) 7.24 (0.34) 6.92 (0.47) 5.43 (0.27)
aaaa
Weigh eloci y (kg/mon hs)
3 mon hs 0.48 (0.03) 0.50 (0.03) 0.44 (0.03) 0.41 (0.03)
aaaa
6 mon hs 0.29 (0.03) 0.33 (0.03) 0.27 (0.03) 0.26 (0.03)
aaaa
12 mon hs 0.21 (0.03) 0.23 (0.03) 0.20 (0.03) 0.19 0.03)
aaa
0.056
24 mon hs 0.18 (0.02) 0.18 (0.03) 0.17 (0.02) 0.17 (0.03)
aa
0.795 0.431
48 mon hs 0.17 (0.02) 0.16 (0.03) 0.15 (0.02) 0.15 (0.03)
a
0.103 0.002 0.796
60 mon hs 0.17 (0.02) 0.15 (0.03) 0.15 (0.02) 0.15 (0.03)
a
0.540
a
0.873
Heigh eloci y (cm/mon hso)
3 mon hs 3.34 (0.17) 2.99 (0.14) 2.41 (0.10) 2.45 (0.11)
aaa
0.002
6 mon hs 1.61 (0.07) 1.62 (0.07) 1.37 (0.08) 1.37 (0.09)
aa
0.221 0.468
12 mon hs 0.94 (0.05) 1.00 (0.07) 0.91 (0.07) 0.89 (0.09)
aaa
0.144
24 mon hs 0.71 (0.04) 0.73 (0.06) 0.70 (0.07) 0.69 (0.09) 0.134
aa
0.211
48 mon hs 0.64 (0.04) 0.63 (0.06) 0.61 (0.06) 0.60 (0.08)
a
0.015 0.019 0.352
60 mon hs 0.63 (0.04) 0.60 (0.06) 0.58 (0.06) 0.58 (0.08)
a
0.123
a
0.393
M5BH boys s. Lungwena boys
F5BH gi ls s. Lungwena gi ls
BH 5BH boys s. BH gi ls
LUN 5Lungwena boys s. Lungwena gi ls
PWV5Peak weigh eloci y (kg/mon hs)
APWV 5Age a peak weigh eloci y (mon h)
PHV5Peak heigh eloci y (cm/mon hs)
APHV5Age a peak heigh eloci y (mon h)
All compa isons done using he - es .
a
:P- alue <0.001.
POSTNATAL GROWTH AND OBESITY IN EARLY ADOLESCENTS 647
Ame ican Jou nal o Human Biology
Rela ionship be ween bi h weigh , g ow h eloci y, peak
eloci y and adolescen obesi y
Table 4 shows he associa ion be ween adolescen o e -
weigh and g ow h eloci y. The s udy ound no associa-
ion be ween sex and being o e weigh adolescen , e en
hough gi ls had lowe odds o being o e weigh compa ed
o boys (OR 50.88, P50.671). The Lungwena coho had
lowe odds o being o e weigh han he BH coho
(OR 50.02, P<0.001). The odds did no change e en a e
adjus ing o sex di e ences. Despi e he odds o being
o e weigh inc easing wi h inc ease in bi h weigh , he
associa ion was no signi ican (OR 51.25, P50.486).
Consis en wi h he obse ed ela ionship be ween
BMI and linea g ow h a es in weigh (b
w
)asshownin
Table 3, he s udy also ound s onges associa ion
be ween being o e weigh and linea g ow h a e in
weigh (b
w
), e en a e adjus ing o coho di e ences
and bi h weigh (OR 52.05, P- alue <0.001). While
he e was a s ong associa ion be ween being an o e -
weigh adolescen and a child’s es ima ed baseline
weigh (a
w
), his ela ionship was no signi ican when
coho di e ences we e aken in o accoun . A e adjus -
ing o coho di e ences and bi h weigh , only he lin-
ea g ow h a e unc ion (b
w
)was ound obeassocia ed
wi h adolescen o e weigh .
The s udy also ound s ong associa ion be ween adoles-
cen o e weigh and linea g ow h a es in heigh , wi h
child en exhibi ing as e heigh g ow h a es being mo e
likely o be o e weigh in adolescence. Howe e , his ela-
ionship was non-signi ican when coho di e ences we e
aken in o accoun . Consis en wi h weigh model pa am-
e e s, baseline heigh (a
h
) and he dec ease in heigh
eloci y o e ime (c
h
) we e also no associa ed wi h being
o e weigh .
The logis ic eg ession models showed a s onge associ-
a ion be ween o e weigh in ea ly adolescence (ages 9–11
yea s) and weigh gain in in ancy han wi h weigh gain
in ea ly childhood. A 3 mon hs, e e y 1 SD inc ease in
weigh eloci y had an eigh old odds o being o e weigh
in ea ly adolescence. These odds educed wi h age such
ha by he ime a child is 5-yea s-old, e e y 1 SD inc ease
in weigh eloci y esul ed in almos h ee old odds o
being o e weigh . Despi e he e being a dec ease in he
odds o being o e weigh a e adjus ing o coho di e -
ences and bi h weigh , he end o e ime was he same.
The same end was obse ed wi h heigh eloci y. How-
e e , he e we e no signi ican associa ion be ween heigh
eloci y and being o e weigh a e adjus ing o bi h
weigh and coho di e ences. No associa ion was ound
be ween obesi y and PHV, age a PHV o age a PWV,
TABLE 3. Rela ionship be ween adolescen BMI and g ow h eloci y, peak eloci y and Reed1 model pa ame e s, adjus ing o sex and coho
di e ences
Main p edic o
Model 1 Model 2 Model 3
b(SE) R
2
b(SE) R
2
b(SE) R
2
Sex : boys Re
gi ls 20.18 (0.09)
a
0.01
Coho : BH Re
LUN 21.07 (0.08) 0.22
Bi h weigh 0.27 (0.10) 0.01
Pa ame e s (weigh )
a
w
0.34 (0.05) 0.08 0.33 (0.05) 0.08 0.25 (0.06)
a
0.27
b
w
21.2 (1.55) 0.25 21.3 (1.61) 0.25 18.9 (1.45) 0.42
c
w
0.96 (0.18) 0.05 1.00 (0.18) 0.07 0.31 (0.21)
a
0.25
d
w
20.05 (0.07)
a
0.001 20.04 (0.07)
a
0.01 0.06 (0.09)
a
0.25
Pa ame e s (heigh )
a
h
0.08 (0.01) 0.15 0.07 (0.01) 0.15 0.001(0.013)
a
0.25
b
h
4.32 (0.62) 0.08 4.18 (0.63) 0.08 2.20 (0.60) 0.26
c
h
20.24 (0.04) 0.05 20.24 (0.04) 0.06 0.017 (0.05)
a
0.25
d
h
20.05 (0.01) 0.16 20.05 (0.002) 0.18 0.001 (0.01)
a
0.25
In an peak eloci y
PWV 1.85 (0.16) 0.20 1.84 (0.16) 0.20 1.86 (0.14) 0.44
PHV 0.35 (0.07) 0.05 0.33 (0.07) 0.05 0.23 (0.06) 0.26
APWV 21.33 (0.19) 0.08 21.39 (0.19) 0.10 1.32 (0.29) 0.27
APHV 20.004 (0.05)
a
0.001 20.008 (0.05)
a
0.01 0.05 (0.04)
a
0.24
Weigh eloci y
3 mon hs 14.8 (0.80) 0.38 14.7 (0.81) 0.38 12.3 (1.05) 0.40
6 mon hs 18.3 (1.03) 0.36 18.2 (1.04) 0.36 14.8 (1.23) 0.40
12 mon hs 21.7 (1.28) 0.34 21.7 (1.31) 0.34 17.4 (1.37) 0.42
24 mon hs 23.5 (1.43) 0.33 23.7 (1.47) 0.33 19.3 (1.42) 0.43
48 mon hs 23.3 (1.50) 0.30 23.5 (1.55) 0.30 19.6 (1.44) 0.43
60 mon hs 22.5 (1.52) 0.29 23.1 (1.57) 0.29 19.5 (1.44) 0.43
Heigh eloci y
3 mon hs 1.31(0.10) 0.24 1.32 (0.10) 0.25 0.81 (0.25) 0.26
6 mon hs 3.68 (0.29) 0.22 3.68 (0.29) 0.24 1.86 (0.50) 0.26
12 mon hs 3.79 (0.54) 0.08 3.72 (0.55) 0.09 1.50 (0.54) 0.26
24 mon hs 3.67 (0.65) 0.05 3.54 (0.65) 0.06 2.22 (0.59) 0.26
48 mon hs 4.07 (0.66) 0.06 3.93 (0.66) 0.07 2.32 (0.61) 0.26
60 mon hs 3.98 (0.65) 0.06 3.83 (0.67) 0.07 2.30 (0.61) 0.26
a
E ec o main p edic o was no signi ican .
Model 1: Adolescen BMI s. main p edic o .
Model 2: Adolescen BMI s. main p edic o (adjus ing o bi h weigh ). Bi h weigh was non-signi ican when adjus ed o he main p edic o s in Model 2.
Model 3: Adolescen BMI s. main p edic o (adjus ing o bi h weigh , sex and coho di e ences).
R
2
5 o al a ia ion in BMI explained by he o e all model.
648 E.D. CHIRWA ET AL.
Ame ican Jou nal o Human Biology
when adjus ed o coho di e ence. Howe e child en
wi h high PWV we e mo e likely o be o e weigh in ado-
lescence e en a e adjus ing o coho di e ences.
DISCUSSION
This s udy has been able o demons a e a posi i e lin-
ea ela ionship be ween apid weigh gain in in ancy and
ea ly childhood and ea ly adolescen BMI, as well as
shown a ela ionship be ween apid g ow h in he ea ly
yea s and he odds o being o e weigh /obese in ea ly
adolescence.
The high odds a io and R
2
alues be ween g ow h
eloci y in he i s yea o li e ( he pe iod which was also
cha ac e ised by high g ow h eloci y) and adolescen
BMI, highligh he associa ion be ween apid weigh gain
and obesi y in ea ly adolescence. The dec easing end in
he OR alues in la e ea ly childhood highligh s he c i i-
cal pe iod du ing in ancy ha is highly associa ed wi h
adolescence/adul obesi y. This suppo s wha p io s ud-
ies in he BH coho and o he s elsewhe e ha e ound,
albei using di e en me hods o measu es (Came on
e al., 2003; Ekelund e al., 2007; McCa hy e al., 2007;
Bo on e al., 2008; Adai e al., 2009; Deme a h e al.,
2009; S ein e al., 2010). In a s udy o he ela ionship
be ween apid weigh gain in he i s 2 yea s o li e and
obesi y in childhood in BH child en wi h app op ia e bi h
weigh o ges a ional age (AGA), Came on e al. (2003),
using weigh - o -age z-sco es, ound ha child en ha
exhibi ed apid g ow h in in ancy we e signi ican ly
alle , and weighed mo e in childhood. Ou s udy has
been able o demons a e his using pa ame e es ima es
om he Reed1 model, wi h he pa ame e b
w
, a unc ion
ela ed o g ow h eloci y being highly posi i ely associ-
a ed wi h ea ly adolescen BMI. Consis en wi h he s udy
by Mook-Kanamo i e al., ou s udy ound high PWV o be
highly associa ed wi h ea ly adolescence o e weigh . The
signi icance o he ela ionship be ween apid weigh gain
in in ancy and adolescen BMI was also highligh ed by
he nega i e associa ed be ween APWV and adolescen
BMI, indica ing ha in an s ha eached in an PWV
ea ly we e mo e likely o ha e high BMI. Apa om ha ,
ou s udy has also explo ed he ela ionship using heigh
eloci y and ex ended he pe iod o ea ly adolescence (9–
11 yea s). Ou s udy has also been able o show simila
associa ion be ween apid g ow h and adolescen BMI in
a u al popula ion, which is om a p edomina ely mal-
nou ished popula ion, wi h high le els o s un ing and
unde weigh . The c i ical pe iod o de elopmen is he
same in bo h coho s. Howe e , he apid in an g ow h in
his u al popula ion seems o ha e bene icial e ec s, as i
p o ec s he adolescen child om he e ec s o unde -
nu i ion,wi h ew cases o obesi y.
The e a e se e al hypo hesised biological ela ionships
be ween p ena al and pos na al g ow h and obesi y in
la e li e, and a la ge body o e idence suppo s hese
hypo hesised ela ionships (Ong and Loos, 2006; Adai ,
2007; Ekelund e al., 2007; Jones-Smi h e al., 2007;
McCa hy e al., 2007; Chom ho e al., 2008; D ue e al.,
2012). These p e ious s udies showed ha ei he small
size a bi h, small size a bi h combined wi h as g ow h
o as g ow h i sel , ha e e ec s on la e li e heal h ou -
comes. S udies ha e also shown ha low-bi h-weigh
in an s usually exhibi apid g ow h du ing he i s yea
o li e (Ong, 2006; Adai , 2007; Johnson e al., 2012). How-
e e , ou s udy which used da a om wo coho s om di -
e en se ings in e ms o en i onmen al and socio-
economic ac o s, ound no ela ionship be ween size a
bi h (bi h weigh ) and g ow h eloci y in bo h coho s.
Simila ly, we ound no associa ion be ween size a bi h
and o e weigh in ea ly adolescence. Bo h bi h weigh
and i s es ima ed pa ame e (a
w
) we e no associa ed wi h
adolescen o e weigh . The non-signi ican ela ionship
be ween bi h weigh and g ow h eloci y as well as wi h
o e weigh in ea ly adolescence could also be due o he
limi ed ange o bi h weigh measu emen s, since ou
sample excluded p e e m babies. E en hough he e was
a wide a ia ion in he age o ini ial weigh measu emen s
o he Lungwena coho , o babies no deli e ed in a
heal h acili y, he mixed e ec s model adjus ed o he
age a which he measu emen s we e aken.
Howe e , he e ec o he di e ences in he en i on-
men al and socio-economic ac o s in he wo coho s we e
shown by he di e ences in he g ow h a es and he pos -
na al p e alence o s un ing/unde weigh and o e weigh
in he coho s as well as he signi icance o coho e m in
he models. Despi e he e being no signi ican di e ences
in bi h weigh s be ween he wo coho s, he u ban BH
child en exhibi ed mo e apid weigh gain in he i s yea
TABLE 4. Odds a ios om he ela ionship be ween o e weigh and
g ow h eloci y, peak eloci y and Reed 1 pa ame e s, adjus ing o
sex and coho di e ence
Main p edic o
Model 1 Model 2 Model 3
a
OR (95% CI) OR (95% CI) OR (95% CI)
Sex :boys Re
:gi ls 0.88 (0.49, 1.58)
b
Coho : BH Re
LUN 0.02 (0.005, 0.09)
Bi h weigh 1.25 (0.67, 2.34)
b
Pa ame e s (weigh )
a
w
1.53 (1.19, 1.97) 1.55 (1.20, 2.02) 1.12 (0.89, 1.40)
b
b
w
2.21 (1.65, 2.96) 2.27 (1.68, 3.08) 2.05 (1.46, 2.87)
c
w
1.46 (1.24, 1.72) 1.48 (1.25, 1.75) 1.08 (0.92, 1.27)
b
d
w
1.06 (0.87, 1.29)
b
1.07 (0.88, 1.31)
b
1.05 (0.92, 1.21)
b
Pa ame e s (heigh )
a
h
1.79 (1.46,2.21) 1.79 (1.45, 2.22) 0.88 (0.67, 1.15)
b
b
h
1.71 (1.21, 2.42) 1.70 (1.20,2.41) 1.14 (0.77, 1.70)
b
c
h
0.74 (0.62, 0.89) 0.74 (0.62, 0.89) 1.05 (0.90, 1.24)
b
d
h
0.53 (0.43, 0.65) 0.53 (0.43, 0.65) 1.10 (0.84, 1.45)
b
In ancy peak eloci y
PWV 1.42 (1.08, 1.87) 1.42 (1.07, 1.88) 1.68 (1.17, 2.42)
PHV 1.58 (0.99, 2.52)
b
1.56 (0.97, 2.50)
b
1.44 (0.76, 2.74)
b
APWV 0.06 (0.01, 0.12) 0.03 (0.01, 0.12) 4.31 (0.78, 23.7)
b
APHV 0.99 (0.74, 1.35)
b
0.99 (0.74, 1.34)
b
1.17 (0.88, 1.55)
b
Weigh eloci y
3 mon hs 7.49 (4.50, 12.46) 7.96 (4.68, 13.52) 4.80 (2.49, 9.26)
6 mon hs 4.07 (2.82, 5.86) 4.09 (2.84, 5.90) 2.60 (1.77, 3.83)
12 mon hs 3.51 (2.48, 4.94) 3.58 (2.52, 5.08) 2.46 (1.89, 3.61)
24 mon hs 3.06 (2.20, 4.25) 3.18 (2.26, 4.47) 2.44 (1.68, 3.55)
48 mon hs 2.67 (1.95, 3.66) 2.78 (2.01, 3.86) 2.41 (1.68, 3.64)
60 mon hs 2.60 (1.90, 3.56) 2.71 (1.96, 3.75) 2.39 (1.65, 3.47)
Heigh eloci y
3 mon hs 3.02 (2.19, 4.15) 3.01 (2.19, 4.14) 0.87 (0.50, 1.50)
b
6 mon hs 5.49 (3.27, 9.22) 5.52 (3.29, 9.24) 1.62 (0.61, 4.32)
b
12 mon hs 2.25 (1.60, 3.15) 2.25 (1.60, 3.16) 1.35 (0.89, 2.03)
b
24 mon hs 1.55 (1.13, 2.14) 1.54 (1.12, 2.13) 1.34 (0.88, 2.04)
b
48 mon hs 1.51 (1.10, 2.09) 1.50 (1.09, 2.07) 1.32 (0.86, 2.03)
b
60 mon hs 1.55 (1.12, 2.14) 1.53 (1.11, 2.13) 1.26 (0.82, 1.94)
b
a
No adjus ed o sex due o limi ed numbe o child en in Lungwena coho
wi h ou come.
b
E ec o main p edic o was no signi ican .
Model 1: O e weigh s. main p edic o .
Model 2: O e weigh s. main p edic o (adjus ing o bi h weigh ).
Model 3: O e weigh s. main p edic o (adjus ing o bi h weigh and coho
di e ences).
POSTNATAL GROWTH AND OBESITY IN EARLY ADOLESCENTS 649
Ame ican Jou nal o Human Biology
o li e. This apid weigh gain was associa ed wi h a high
p e alence o o e weigh adolescen s in his popula ion.
The di e ences in he p e alence o o e weigh adoles-
cen s in he wo coho s, conside ing he non-signi ican
di e ences in hei size a bi h, highligh s he signi i-
cance o apid weigh gain a he han bi h size, in he
ela ionship be ween ea ly g ow h and obesi y in adoles-
cence, in his pa icula se ing. These esul s a e in sup-
po o he “ as g ow h and obesi y” hypo hesis, a he
han he “size a bi h” o he “size a bi h and as
g ow h” hypo heses. The ela ionship be ween as e
g ow h eloci y and obesi y/o e weigh in la e li e, inde-
penden o bi h weigh , has been hypo hesised o be
mainly due o o e -nu i ion (Jones-Smi h e al., 2013).
The mo e apid weigh gain in he BH coho ela i e o
he Lungwena coho may be due o nu i ional and en i-
onmen al di e ences, among o he ac o s. The slowe
weigh eloci y in he Lungwena coho , om as ea ly as
3 mon hs, could be due o poo ma e nal nu i ional s a-
us and he ea ly in oduc ion o complemen a y oods. As
Lungwena is p edomina ely a poo u al communi y, he
complemen a y oods used a e likely o be o poo nu i-
ional con en and o expose he in an s o pa hogens
(Espo e al., 2002).
Ou esul s a e in gene al consis en wi h s udy by
Adai e al. (2013), which also looked a associa ion
be ween weigh and heigh gain, and adul heal h ou -
comes in i e coho s om LMIC (Adai e al., 2013). The
s udy ound a posi i e ela ionship be ween weigh gain
and adul BMI, wi h he s eng h o he ela ionship
inc easing wi h age a which measu emen was aken.
Howe e , unlike ou s udy, hey also ound posi i e ela-
ionship be ween bi h weigh and adul BMI, and hey
also ound a dec easing ela ionship be ween heigh gain
and BMI. The a ia ions in hese esul s could be due o
he di e ences in he age anges used as well as he lim-
i ed amoun o obse a ions a 3 and 6 mon hs in he BH
coho o ou s udy.
Apa om looking a coho s om di e en SES and
en i onmen al se ings, he o he s eng h o his s udy is
in he use o mixed e ec s modelling o model g ow h a-
jec o ies and o de i e g ow h eloci ies. Mixed e ec s
modelling allowed us o compa e g ow h eloci y a any
age e en hough some o he da a collec ion wa es in he
wo coho s we e a di e en imes. Ou esul s a e in
gene al, consis en wi h esul s om o he s udies ha
ha e used mixed e ec s. In a s udy o Du ch child en,
Mook-Kanamo i e al., also using he Be key-Reed model
and mixed e ec s modelling, ound ha apid weigh gain
in he i s mon hs was mo e associa ed wi h isk o o e -
weigh han ca ch-up g ow h (‘size a bi h and as
g ow h hypo hesis’) du ing he i s 2 yea s (Mook-Kana-
mo i e al., 2011). Simila ly, Bo on e al. (2008) using he
adap ed Jenns-Bayley model and using mixed e ec s
modelling, also ound inc eased isk o obesi y due o
apid g ow h in he i s 6 mon hs in F ench child en.
Howe e , hei s udy also ound ha his isk s a ed
inc easing again om 3 yea s. Howe e , hey de i ed
hei g ow h eloci y om a model i ed om bi h o 10
yea s, which may ha e made i possible o pick ou he
inc ease in g ow h eloci y om 3 yea s. Ou s udy i ed
he g ow h model up o 5 yea s only.
The main limi a ion o he s udy is una ailabili y o
da a on adolescen ac o s associa ed wi h BMI in one o
he coho , which could ha e been adjus ed o in he ela-
ionship be ween pos na al g ow h and adolescen BMI/
o e weigh . The o he limi a ion o he s udy is he
amoun o missing weigh and heigh measu emen s du -
ing he i s yea o li e in he BH coho which could ha e
a ec ed he i ness o he g ow h model used o es ima -
ing g ow h eloci y.
In conclusion, al hough ou esul s suppo he hypo h-
esis ha apid g ow h in in ancy inc eases he isk o
o e weigh / obesi y in la e li e, he long e m e ec s o
in ancy apid g ow h a e dependen on he pa icula pop-
ula ion’s s age o nu i ion ansi ion. Fo a popula ion in
ea ly s ages o nu i ion ansi ion o wi h poo nu i-
ional s a us, apid g ow h in ea ly childhood may ha e
long e m bene icial e ec s as was e idenced by he
almos non-exis en p e alence o o e weigh in he Lung-
wena coho , despi e some child en exhibi ing apid
g ow h in ea ly childhood. Con e sely, o popula ions
unde going apid nu i ion ansi ion as is he case wi h
he BH coho , apid g ow h has de imen al long e m
e ec s, as was e idenced by he p e alence o o e weigh
and obesi y in ea ly adolescence. To u he explo e he
ela ionship be ween pos na al g ow h eloci y and la e
heal h ou come, we would ecommend modelling g ow h
in o adolescence and also include pube al s ages and SES
ac o s du ing adolescence ha a e highly associa ed wi h
BMI, such as die a y pa e ns and physical ac i i y
beha io s o he adolescen s in he coho s. Fu he s ud-
ies in simila coho s in LMIC migh also help in explain-
ing he e ec o shi s in die a y and seden a y beha io s
associa ed wi h u baniza ion.
LITERATURE CITED
Adai L. 2007. Size a bi h and g ow h ajec o ies o young adul hood.
Am J Hum Biol 19:327–337.
Adai LS, Fall CH, Osmond C, S ein AD, Ma o ell R, Rami ez-Zea M,
Sachde HS, Dahly DL, Bas I, No is SA, Mickles ield L, Hallal P,
Vic o a CG. 2013. Associa ions o linea g ow h and ela i e weigh gain
du ing ea ly li e wi h adul heal h and human capi al in coun ies o low
and middle income: indings om i e bi h coho s udies. Lance 382:
525–534.
Adai LS, Ma o ell R, S ein AD, Hallal PC, Sachde HS, P abhaka an D,
Wills AK, No is SA, Dahly DL, Lee NR, Vic o a CG. 2009. Size a bi h,
weigh gain in in ancy and childhood, and adul blood p essu e in 5 low-
and middle-income-coun y coho s: when does weigh gain ma e ? Am
J Clin Nu 89:1383–1392.
Be key CS. 1982. Compa ison o wo longi udinal g ow h models o p e-
school child en. Biome ics 38:221–234.
Black MM, K ishnakuma A. 1999. P edic ing longi udinal g ow h cu es
o heigh and weigh using ecological ac o s o child en wi h and wi h-
ou ea ly g ow h de iciency. J Nu 129 (2S Suppl):539S–543S.
Bo on J, Heude B, Macca io J, Ducime ie e P, Cha les M. 2008. Pos na al
weigh and heigh g ow h eloci ies a di e en ages be ween bi h and
5y and body composi ion in adolescen boys and gi ls. Am J Clin Nu
87:1760–1768.
Came on N. 1984. The measu emen o human g ow h. London: C oom
Helm.
Came on N, Deme a h EW. 2002. C i ical pe iods in human g ow h and
hei ela ionship o diseases o aging. Am J Phys An h opol Suppl 35:
159–184.
Came on N, Pe i o J, De We T, No is S. 2003. The ela ionship o apid
weigh gain in in ancy o obesi y and skele al ma u i y in childhood.
Obes Res 11:457–460.
Came on N, W igh MM, G i i hs PL, No is SA, Pe i o JM. 2005.
S un ing a 2 yea s in ela ion o body composi ion a 9 yea s in A ican
u ban child en. Obes Res 13:131–136.
Chi wa ED, G i i hs PL, Male a K, No is SA, Came on N. 2014. Mul i-
le el modelling o longi udinal child g ow h da a om he Bi h- o-
Twen y Coho : a compa ison o g ow h models. Ann Hum Biol 41:166–
177.
Chom ho S, Wells JC, Williams JE, Lucas A, Few ell MS. 2008. Associa-
ions be ween bi h weigh and la e body composi ion: e idence om
he 4-componen model. Am J Clin Nu 88:1040–1048.
650 E.D. CHIRWA ET AL.
Ame ican Jou nal o Human Biology
Cole TJ, Bellizzi MC, Flegal KM, Die z WH. 2000. Es ablishing a s anda d
de ini ion o child o e weigh and obesi y wo ldwide: in e na ional su -
ey. BMJ 320:1240–1243.
Cole TJ, Flegal KM, Nicholls D, Jackson AA. 2007. Body mass index cu
o s o de ine hinness in child en and adolescen s: in e na ional su ey.
BMJ 335:194.
Deme a h EW, Jones LL, Hawley NL, No is SA, Pe i o JM, Du en D,
Chumlea WC, Towne B, Came on N. 2009. Rapid in an weigh gain and
ad anced skele al ma u a ion in childhood. J Pedia 155:355–361.
D ue C, S e le N, Sha p S, Simmons RK, Coope C, Smi h GD, Ekelund
U, Le y-Ma chal C, Ja elin MR, Kuh D, Ong KK. 2012. P edic ion o
childhood obesi y by in ancy weigh gain: an indi idual-le el me a-anal-
ysis. Paedia Pe ina Epidemiol 26:19–26.
Ekelund U, Ong KK, Linne Y, Neoyius M, B age S, Dunge DB, Wa eham
NJ, Rossne S. 2007. Associa ion o weigh gain in in ancy and ea ly
childhood wi h me abolic isk in young adul s. J Clin Endoc inol Me ab
92:98–103.
Espo M, Kulmala T, Male a K, Cullinan T, Salin ML, Asho n P. 2002.
De e minan s o linea g ow h and p edic o s o se e e s un ing du ing
in ancy in u al Malawi. Ac a Paedia 91:1364–1370.
Flexede C, Thie ing E, B uske I, Kole zko S, Baue CP, Wichmann HE,
Mansmann U, Von Be g A, Be del D, K ame U, Schaa B, Lehmann I,
He ba h O, Hein ich J. 2012. G ow h eloci y du ing in ancy and onse
o as hma in school-aged child en. Alle gy 67:257–264.
Hoddino J, Maluccio JA, Maluccio JA, Beh man JR, Flo es R, Ma o ell
R. 2008. E ec o a nu i ion in e en ion du ing ea ly childhood on eco-
nomic p oduc i i y in Gua emalan adul s. Lance 371:411–416.
Ho man DJ, Sawaya AL, Ve eschi I, Tucke KL, Robe s SB. 2000. Why
a e nu i ionally s un ed child en a inc eased isk o obesi y? S udies
o me abolic a e and a oxida ion in shan y own child en om Sao
Paulo, B azil. Am J Clin Nu 72:702–707.
Johnson W, Vazi S, Fe nandez-Rao S, Kankipa i VR, Balak ishna N,
G i i hs PL. 2012. Using he WHO 2006 child g ow h s anda d o assess
he g ow h and nu i ional s a us o u al sou h Indian in an s. Ann
Hum Biol 39:91–101.
Jones-Smi h JC, Fe nald LC, Neu eld LM. 2007. Bi h size and accele -
a ed g ow h du ing in ancy a e associa ed wi h inc eased odds o child-
hood o e weigh in Mexican child en. J Am Die Assoc 107:2061–2069.
Jones-Smi h JC, Neu eld LM, La aia B, Ramak ishnan U, Ga cia-Gue a
A, Fe nald LC. 2013. Ea ly li e g ow h ajec o ies and u u e isk o
o e weigh . Nu Diabe es 3:e60.
Kalanda BF, an Buu en S, Ve hoe FH, B abin BJ. 2005. Ca ch-up
g ow h in Malawian babies, a longi udinal s udy o no mal and low
bi hweigh babies bo n in a mala ious endemic a ea. Ea ly Hum De
81:841–850.
Li H, S ein AD, Ban ha HX, Ramak ishnan U, Ma o ell R. 2003. Associ-
a ion be ween p ena al and pos na al g ow h and adul body size and
composi ion. Am J Clin Nu 77:1498–1505.
Male a K, Vi anen SM, Espo M, Kulmala T, Asho n P. 2003. Seasonali y
o g ow h and he ela ionship be ween weigh and heigh gain in chil-
d en unde h ee yea s o age in u al Malawi. Ac a Paedia 92:491–
497.
Ma o ell R, Sch oede DG, Ri e a JA, Kaplowi z HJ. 1995. Pa e ns o
linea g ow h in u al Gua emalan adolescen s. J Nu 125 (4 Suppl):
1060s–1067s.
McCa hy A, Hughes R, Tilling K, Da ies D, Smi h GD, Ben-Shlomo Y.
2007. Bi h weigh ; pos na al, in an , and childhood g ow h; and obesi y
in young adul hood: e idence om he Ba y Cae philly G ow h S udy.
Am J Clin Nu 86:907–913.
Mesa JM, A aujo C, Ho a BL, Gigan e DP. 2010. G ow h pa e ns in ea ly
childhood and he onse o mena che be o e age wel e. Re Saude Pub-
lica 44:249–260.
Mook-Kanamo i DO, Du mus B, So io U, Ho man A, Raa H, S eege s EA,
Ja elin MR, Jaddoe VW. 2011. Fe al and in an g ow h and he isk o
obesi y du ing ea ly childhood: he Gene a ion R S udy. Eu J Endoc i-
nol 165:623–630.
Ong KK. 2006. Size a bi h, pos na al g ow h and isk o obesi y. Ho m
Res 65 (Suppl 3):65–69.
Ong KK, Loos RJ. 2006. Rapid in ancy weigh gain and subsequen obesi y:
sys ema ic e iews and hope ul sugges ions. Ac a Paedia 95:904–908.
Ong KK, Ahmed ML, Emme PM, P eece MA Dunge DB. 2000. Associa-
ion be ween pos na al ca ch-up g ow h and obesi y in childhood: p o-
spec i e coho s udy. BMJ 320:967–971.
Ridgway CL, Ong KK, Tammelin T, Sha p SJ, Ekelund U, Ja elin MR.
2009. Bi h size, in an weigh gain, and mo o de elopmen in luence
adul physical pe o mance. Med Sci Spo s Exe c 41:1212–1221.
Salonen MK, Kajan ie E, Osmond C, Fo sen T, Yliha sila H, Paile-
Hy a inen M, Ba ke DJ, E iksson JG. 2009. Childhood g ow h and
u u e isk o he me abolic synd ome in no mal-weigh men and
women. Diabe es Me ab 35:143–150.
Sch oede DG, Ma o ell R, Flo es R. 1999. In an and child g ow h and a -
ness and a dis ibu ion in Gua emalan adul s. Am J Epidemiol 149:
177–185.
Simondon KB, Simondon F, Delpeuch F, Co nu A. 1992. Compa a i e
s udy o i e g ow h modelsaplied o weigh da a om congolese in an s
be ween bi h and 13 mon hs o age. Am J Hum Biol 4:327–335.
S ein AD, Wang M, Ma o ell R, No is SA Adai LS, Bas I, Sachde HS,
Bha ga a SK, Fall CH, Gigan e DP, Vic o a CG. 2010. G ow h pa e ns
in ea ly childhood and inal a ained s a u e: da a om i e bi h
coho s om low- and middle-income coun ies. Am J Hum Biol 22:353–
359.
Vic o a CG, Ba os FC, Ho a BL, Ma o ell R. 2001. Sho - e m bene i s
o ca ch-up g ow h o small- o -ges a ional-age in an s. In J Epidemiol
30:1325–1330.
Vic o a CG, Adai L, Fall C, Hallal PC, Ma o ell R, Rich e L, Sachde
HS. 2008. Ma e nal and child unde nu i ion: consequences o adul
heal h and human capi al. Lance 371:340–357.
Walke SP, Chang SM, Powell CA. 2007. The associa ion be ween ea ly
childhood s un ing and weigh s a us in la e adolescence. In J Obes 31:
347–352.
POSTNATAL GROWTH AND OBESITY IN EARLY ADOLESCENTS 651
Ame ican Jou nal o Human Biology