1
Physical and men al s ain a wo k: Rela ionships wi h onse
and pe sis ence o mul i-si e pain in a ou -yea ollow up
Subas Neupane1, 2 *, Clas-Håkan Nygå d1, 2
1School o Heal h Sciences FI – 33014, Uni e si y o Tampe e, Tampe e Finland
2Ge on ology Resea ch Cen e , FI – 33014, Uni e si y o Tampe e
*Co esponding au ho : D . Subas Neupane
School o Heal h Science
FI – 33014 Uni e si y o Tampe e, Finland
Email subas.neupane@u a. i
Phone +358 40 1909709
Fax +358 3 35516057
Running i le: Men al and physical s ain and mul i-si e pain
2
Abs ac
This s udy e alua es whe he physical and men al s ain a e associa ed wi h an onse and
pe sis ence o mul i-si e pain among younge and olde employees in a ou yea o ollow-
up. A ques ionnai e su ey was conduc ed in a ood p ocessing company wice, in 2005
and 2009 wi h he esponse om 734 employees in he age be ween 20 and 66 yea s (445
younge and 289 olde ; 65% emale). In o ma ion on musculoskele al pain du ing he
p eceding week and pe cei ed men al and physical s ain was ob ained h ough a s uc u ed
ques ionnai e. The associa ion o onse and pe sis ence o mul i-si e pain wi h men al and
physical s ain was es ima ed wi h log binomial eg ession analysis and s a i ied by age-
g oup. Risk a io (RR) wi h hei 95% con idence in e als (CIs) a e epo ed o he
es ima es. Mo e han 56% o he employees epo ed mul i-si e pain a baseline. Among
hose who epo ed mul i-si e pain a baseline 70% epo ed pe sis ence o mul i-si e pain
and one hi d had new onse o mul i-si e pain a he ollow-up. Men al s ain a baseline
s ongly p edic ed pe sis ence o mul i-si e pain among bo h younge and olde employees
(RR om o younge employees = 1.68, 95% CI = 1.01-2.83 and RR o olde employees
= 2.25, 95% CI 0 1.27-3.98). The high men al s ain p edic ed he isk o pe sis ence mul i-
si e pain among bo h younge and olde employees in a ou yea ollow-up bu no onse
o mul i-si e pain.
Key wo ds: musculoskele al pain; mul i-si e pain; men al s ain; physical s ain
3
Highligh s
•The e is an inc eased a en ion o he ela ionship be ween wo k exposu es and
musculoskele al diso de s in ecen esea ch.
•Men al s ain a baseline was s ong p edic o o pe sis ence o mul i-si e pain
musculoskele al pain bo h among younge and olde employees.
•In e en ions in he wo kplaces ocusing on he indi idual le el would educe
physical and men al s ain as a esul lowe he incidence o mul i-si e pain o bo h
younge and olde employees.
4
INTRODUCTION
Musculoskele al pain in mul iple body si es is equen in he wo king popula ion (Neupane
e al, 2013a; Haukka e al, 2013; He in e al, 2014). A la ge body o esea ch howe e
ocused on a single body si e. Associa ion be ween ce ain physical (physical wo k load,
epe i i e ask, awkwa d pos u e) and psychosocial exposu es (high job demands, low job
con ol, co-wo ke s and supe iso s suppo ) a wo k and pain ul condi ions a pa icula
ana omical si es has been s udied ex ensi ely. E idence shows ha pain in mul iple body
si e is associa ed wi h dec eased unc ioning and wo se p ognosis when compa ed o
ha ing pain in only one body si e (Neupane e al, 2014; Haukka e al, 2013; Kamale i e
al, 2008; Mi anda e al, 2010). Howe e less is known abou he ela ionship o mul i-si e
musculoskele al pain wi h men al and physical s ain ela ed wo k exposu es.
The concep o s ain in his s udy is based on he s ess-s ain model whe e he s ess on a
wo ke depends on en i onmen al ac o s (bo h physical and psychosocial) ac ing upon he
pe son, whe eas s ain deno es he e ec s o s ess which di e by indi idual o a ce ain
s ess ac o (Ru en an z, 1981; Cox e al, 2000). The s ess and s ain concep has been
widely used in s udies on he e ec s o physical wo k load on bo h he ca dio ascula as
well as he musculoskele al sys em (Ru en anz, 1981, Nygå d e al, 1988). The model
emphasizes he ole o indi idual cha ac e is ics such as age, gende , heal h s a us and wo k
abili y as modi ie s o he ela ionship be ween s ain and musculoskele al symp oms o
pain.
5
Indus ial wo ke s a e mos ly exposed o physical s ain (Nico , 2007). The high s ain is
mos ly due o he physical wo k en i onmen in he indus y. In a c oss-sec ional s udy
among men and women employed in di e en occupa ions, physical s ain was associa ed
wi h musculoskele al symp oms (Johansson, 1995). One ea lie s udy among heal h ca e
employees, men al s ain was ound o be a isk ac o o musculoskele al symp oms in a
h ee yea ollow-up (Josephson e al, 1997). I also ound ha he isk was highe when i
was combined wi h pe cei ed high physical exe ion. Psychological o men al s ain has
also been ound o be linked o poo ou comes such as ea ly e i emen (Laine e al, 2008)
and mo ali y (Ki imäki e al, 2002). In a 28 yea s o ollow-up s udy, wo k s ain (bo h
men al and physical) du ing midli e among municipal employees was ound o be s ongly
ela ed o declined wo k abili y in old age ( on Bonsdo e al, 2012) and s ess symp oms
in midli e p edic ed disabili y a e 28 yea s (Kulmala e al, 2013).
Ea lie s udies ha e epo ed he ela ionship o s ain and age wi h inconclusi e indings.
One s udy has shown ha olde employees expe ience highe s ain han younge
employees (Nygå d e al., 1997). Howe e , Pailhe (2005) epo ed ha younge coho s a e
exposed o physical s ain mo e equen ly han olde coho s. In his s udy o 4 yea s o
p ospec i e ollow-up o indus ial employees we e alua ed whe he physical and men al
s ain we e associa ed wi h an onse and pe sis ence o mul i-si e pain. We we e also
in e es ed whe he he associa ion we e di e en o younge and olde employees.
METHODS

6
This s udy is based on ques ionnai e su eys conduc ed among all employees o one o he
leading ood indus ies in Finland (1985 employees) in sp ing 2005 and sp ing 2009. The
ques ionnai es we e dis ibu ed a he wo kplaces o e e y employee ( esponse a e 60%).
I was possible o eply anonymously o o sign he consen o indi idual ollow-up o he
su eys and o linking o he pe sonnel egis e s o he company including in o ma ion on
age, gende occupa ional s a us, wo kplace and du a ion and in e up ions o he job
con ac . The eplies we e placed in sealed en elopes which we e collec ed and o wa ded
o he esea che s. As he ques ion o ms we e no add essed o indi idual employees, no
eminde s could be sen . The s udy was app o ed by he e hical commi ee o Pi kanmaa
Hospi al Dis ic .
Measu emen o a iables
A modi ica ion o he alida ed No dic Musculoskele al ques ionnai e (Kuo inka e al.
1987) was used o assess musculoskele al pain. I included a ques ion ega ding whe he
he employee had el pain, aching o numbness in ou ana omical a eas (hands o uppe
ex emi ies; neck o shoulde s; lowe back; and ee o lowe ex emi ies) du ing he
p eceding week, wi h he eply scale being om 0 (no a all) o 10 ( e y much). The
a iables we e dicho omised a he median (less han median: 0= mild; mo e han median:
1= se e e). The cu -o alues o uppe ex emi ies, neck and shoulde , lowe back and
lowe ex emi ies we e 4, 5, 2 and 2, espec i ely. The dicho omised a iables we e
summed up in o a a iable exp essing he numbe o a eas wi h se e e pain ( om ze o o
ou ) (Neupane e al. 2013a; Neupane e al. 2013b). The summed a iable was u he
7
ca ego ized in o wo, lea ing ze o and one as ‘no mul i-si e pain’ and ‘mul i-si e pain’ by
combining wo, h ee and ou si es pain.
Men al s ain
Pe cei ed men al s ain was assessed by a modi ied e sion o he occupa ional s ess
ques ionnai e (Elo e al., 1992), using a single ques ion (“S ess means a si ua ion in which
a pe son eels exci ed, app ehensi e/conce ned, ne ous o dis essed o she/he canno
sleep because o he hings on he /his mind. Do you eel his kind o s ess nowadays?”)
(Elo e al., 1992), wi h he eply scale om 0 (no a all) o10 ( e y much). Fo his analysis,
men al s ain was ca ego ized in o low (0-2), medium (3-6) and high (7-10) by hei e ile
alues.
Physical s ain
Pe cei ed physical s ain was elici ed wi h he a ing o pe cei ed exe ion (RPE) wi h he
ques ion “How physically ha d/ exhaus ing do you eel you job is in a no mal wo k day?”
on a scale om 6 (no a all) o 20 ( e y much) (Bo g, 1970). Physical s ain in his s udy
was ca ego ized in o h ee low (6-11), medium (12-15) and high (16-20) based on he e ile
alues.
Co a ia es:
Wo k abili y was assessed wi h one ques ion om he wo k abili y index as a subjec i e
assessmen o cu en wo k abili y compa ed wi h a pe son’s sel -iden i ied li e ime bes
(i.e. wi h he ques ion “Assume ha you wo k abili y a i s bes has a alue o 10 poin s.
8
Wha sco e would you gi e you cu en wo k abili y?”). Wo k abili y was ca ego ized in o
excellen (sco e 10), good (sco e 9), mode a e (sco e 8) and poo (sco es 0-7) wo k abili y
in his s udy (Gould e al, 2008).
Body mass index (BMI) was calcula ed using wo ke s’ sel - epo ed weigh (kg) and heigh
(m). The le el o physical exe cise du ing he las mon h was elici ed on a scale om 0
(no a all) o 7 (s enuous physical ac i i y o mo e han 3 hou s a week).
S a is ical Analysis
Desc ip i e s a is ics o he s udy popula ion was p esen ed i s in he o m o equencies
and pe cen ages in o al s a i ied by age g oup (<45 yea s ‘younge ’ and ≥45 ‘olde ’). Log
binomial eg ession analysis was pe o med o examine whe he baseline men al and
physical s ain we e associa ed o mul i-si e pain a e ou yea s o ollow-up. Risk a ios
(RR) wi h hei 95% con idence in e als (CI) a e p esen ed. The analyses we e conduc ed
sepa a ely o hose who had mul i-si e pain a baseline ('pe sis ence o mul i-si e pain')
and hose wi h no mul i-si e pain a baseline (‘onse o mul i-si e pain’). And again bo h
analyses we e s a i ied by age g oup in o de o see he di e ence be ween age g oup. The
models we e buil up in 3 s eps: Model I: c ude isk a ios, Model II: adjus ed o gende
and occupa ional s a us and las ly Model III: includes gende , occupa ional s a us, physical
exe cise, BMI and baseline wo k abili y. All he analyses we e ca ied ou wi h he
s a is ical package SPSS e sion 21.0.
RESULTS
9
Table 1 shows he desc ip i e cha ac e is ics o he s udy popula ion a baseline. Wi hin
he o al o 734 s udy popula ion, 60% we e less han 45 yea s o old. Abou wo hi d o
he s udy popula ion we e emale and mo e han 70% we e blue-colla employees. The e
we e mo e male and blue-colla employees in he younge age g oup and mo e emale and
whi e-colla employees in he olde age. One hi d o he s udy popula ion had high
physical exe cise which no much di e ed be ween age g oups. A li le mo e han one i h
o he people had BMI ≥ 29.0 Kg/m2 and almos 30% o he younge employees had low
(<23.0 kg/m2) BMI and 25% o he olde employees had high (≥ 29.0 Kg/m2) BMI. Abou
15% o he s udy popula ion had poo wo k abili y a baseline and abou he same numbe
(16%) had epo ed excellen wo k abili y. Wi hin he age g oup, almos one i h o
younge employees had excellen wo k abili y compa ed o 11% in hei olde coun e pa s.
Physical s ain was compa a i ely high (30% s. 27%) among younge employees while
men al s ain was high among olde employees (30% s. 21%). Mo e han 56% o he
employees epo ed mul i-si e pain a baseline. Compa a i ely younge employees epo ed
mul i-si e pain mo e o en han hei olde coun e pa s.
Risk a ios and hei 95% CI o mul i-si e pain a ollow-up due o physical and men al
s ain among he coho wi h no mul i-si e pain a baseline a e p esen ed in Table 2. One
hi d o he s udy popula ion had new onse o mul i-si e pain. High physical s ain was
ound o be associa ed wi h onse o mul i-si e pain among all in he c ude model (RR =
1.48, 95% CI = 1.01-2.18) bu signi icance associa ion was los when adjus ed in model II
and model III. Al hough no signi ican , he employees wi h high men al s ain had highe
isk o ha ing new onse o mul i-si e pain in he ou yea ollow-up. Employees wi h high
16
Hannan, L.M., Mon eilh, C.P., Ge , F., Kleinbaum, D.G., and Ma cus, M., 2005. Job
s ain and isk o musculoskele al sysmp oms among a p ospec i e coho o
occupa ional compu e use s. Scand. J. Wo k En i on. Heal h 31, 375-386.
Haukka E., Kaila-Kangas L., Ojajä i A., Mi anda H., Ka ppinen J., Viika i-Jun u a E.,
Heliö aa a M., and Leino-A jas P., 2013. Pain in mul iple si es and sickness
absence ajec o ies: A p ospec i e s udy among Finns. Pain 154, 306-312.
He in F., Vezina M., Thaon I., Soula J-M., Pa is C., and ESTEV g oup. 2014. P edic i e
isk ac o s o ch onic egional and mul isi e musculoskele al pain: A 5-yea
p ospec i e s udy in a wo king popula ion. Pain 155, 937-943.
Johansson A., 1995. The impac o decision la i ude, psychological load and social
suppo a wo k on musculoskele al symp oms. Eu J Public Heal h 5, 169-74.
Josephson M, Lage s öm M, Hagbe g M, Hjelm EW., 1997. Musculoskele al symp oms
and job s ain among nu sing pe sonnel: a s udy o e a h ee yea pe iod. Occup
En i on Med. 54, 681-685.
Kamale i Y, Na ig B, Ihlebaek CM, B uusgaa d D., 2008. Localized o widesp ead
musculoskele al pain: does i ma e ? Pain 138, 41-6.
Ki imäki M, Leino-A jas P, Luukkonen R, Riihimaki H, Vah e a J, Ki jonen J., 2002.
Wo k s ess and isk o ca dio ascula mo ali y: p ospec i e coho s udy o
indus ial employees. BMJ 325, 857.
Kulmala J, on Bonsdo MB, S enholm S, Tö mäkangas T, on Bonsdo ME, Nygå d
C-H, Klocka s M, Sei samo J, Ilma inen J, Ran anen T., 2013. Pe cei ed s ess
symp oms in midli e p edic disabili y in old age: A 28-yea p ospec i e coho
s udy. J Ge on ol A Biol Sci Med Sci. 68, 984-991.

17
Kuo inka I, Jonsson B, Kilbom A, Vin e be g H, Bie ing-So enson F, Ande son G e al.,
1987. S anda dised No dic Ques ionnai es o he analysis o musculoskele al
symp oms. Appl E gon 18, 233–237.
Laine, S., Gimeno, D., Vi anen, M., Oksanen, T., Vah e a, J., Elo ainio, M., Koskinen,
A., Pen i, J., Ki imäki, M., 2008. Job s ain as a p edic o o disabili y pension:
he Finnish Public Sec o S udy. J. Epidemiol. Communi y Heal h 63, 24–30.
Leino, P., 1989. Symp oms o s ess p edic musculoskele al diso de s. J. Epidemol.
Communi y Heal h 43, 293-300.
Mi anda H, Kaila-Kangas L, Heliö aa a M, Leino-A jas P, Haukka E, Lii a J, e al.,
2010. Musculoskele al pain a mul iple si es and i s e ec s on wo k abili y in a
gene al wo king popula ion. Occup En i on Med. 67, 449-55.
Na ig, B., B uusgaa d, D., E iksen, W., 2001. Localized low back pain and low back
pain as pa o widesp ead pain musculoskele al pain: wo di e en diso de s? A
c oss-sec ional popula ion s udy. J. Rehabil. Med. 33, 21-25.
Neupane, S., Leino-A jas, P., Nygå d, C-H., Mi anda, H., Siukola, A., Vi anen, P., 2014.
Does he associa ion be ween musculoskele al pain and sickness absence due o
musculoskele al diagnoses depend on biomechanical wo king condi ions? In .
A ch. Occup. En i on Healh DOI 10.1007/s00420-014-0957-2.
Neupane S, Vi anen P, Leino-A jas P, Mi anda H, Siukola A, Nygå d C-H., 2013a.
Mul i-si e pain and wo king condi ions as p edic o s o wo k abili y in a 4-yea
ollow-up among ood indus y employees. Eu J Pain 17, 444–451.
Neupane S, Mi anda H, Vi anen P, Siukola A, Nygå d C-H., 2013b. Do physical o
psychosocial ac o s a wo k p edic mul i-si e musculoskele al pain? A 4-yea
18
ollow-up s udy in an indus ial popula ion. In A ch Occup En i on Heal h 86,
581-589.
Nico AM., 2007. A e iew o wo king condi ions in F ance. Eu opean Founda ion o
he Imp o emen o Li ing and Wo king Condi ions.
Nygå d C-H, Huuh anen, P, Tuomi, K., 1997. Pe cei ed wo k changes be ween 1981 and
1992 among aging wo ke s in Finland. Scad J Wo k En i on Heal h 23 (suppl 1),
12-9.
Nygå d C-H., Suu näkki T. and Ilma inen J., 1988. E ec s o musculoskele al wo k load
and muscle s eng h on s ain a wo k in women and men aged 44 o 58 yea s. Eu
J Appl Physiol 58:13-19.
Pailhe A., 2005. Wo king Condi ions: How a e olde wo ke s p o ec ed in F ance?
Ins i u Na ional d’E udes Demog aphiques/ popula ion 60, 93-118.
Ru en an z J., 1981. A bei smedizinische Aspek e dess S ess-p oblems. In: Ni sch JR
(ed) Theo ien, Un e suchungen Massnahmen. Be n: Hans Hube 379-390 [in
Ge man].
Siukola A., Vi anen P., Luukkaala T., Nygå d C-H., 2011. Pe cei ed wo king condi ions
and sickness absences- A ou -yea ollow-up in he ood indus y. Sa Heal h
Wo k 2: 313-320.
on Bonsdo MB, Sei samo J, Ilma inen J, Nygå d C-H, on Bonsdo ME, Ran anen
T., 2012. Wo k abili y as a de e minan o old age disabili y se e i y : e idence
om he 28-yea Finnish Longi udinal S udy on Municipal Employees. Aging
Clin Exp Res 24, 354-360.
19
Wahls öm, J., Hagbe g, M., Toomingas, A., To nq is , E.W., 2004. Pe cei ed muscula
ension, job s ain, physical exposu e, and associa ions wi h neck pain among
VDU use s; a p ospec i e coho s udy. Occup. En i on. Med. 61, 523-528.
Yu, S., Naka a, A., Gu, G., Swanson N.G., He, L., Zhou, W., Wang, S., 2013. Job s ain,
e o - ewa d imbalance and neck, shoulde and w is symp oms among Chinese
wo ke s. Ind. Heal h 51, 180-192.
20
Table 1: Baseline cha ac e is ics o he s udy popula ion
Cha ac e is ics All Younge (<45 yea s) Olde (≥45 yea s)
N=734 % N=445 % N=289 %
Gende
Male 255 34.7 173 38.9 82 28.4
Female 479 65.3 272 61.1 207 71.6
Occupa ional s a us
Blue-colla 518 70.6 327 73.5 191 66.1
Whi e-colla 216 29.4 118 26.5 98 33.9
Physical exe cise
Less 322 44.1 193 43.6 129 44.9
Mode a e 162 22.2 94 21.2 68 23.7
High 246 33.7 156 35.2 90 31.4
BMI
<23.0 180 24.5 129 29.0 51 17.6
23.0-25.9 230 31.3 136 30.6 94 32.5
26.0-28.9 153 20.8 82 18.4 71 24.6
≥29.0 171 23.3 98 22.0 73 25.3
Wo k abili y
Poo 106 14.5 63 14.3 43 14.9
Mode a e 235 32.1 130 29.4 105 36.3
Good 274 37.5 165 37.3 109 37.7
Excellen 116 15.9 84 19.0 32 11.1
Physical s ain
Low 247 33.7 140 31.5 107 37.2
Medium 273 37.3 169 38.1 104 36.1
High 212 29.0 135 30.4 77 26.7
Men al S ain
Low 267 36.4 166 37.4 101 34.9
Medium 288 39.3 186 41.9 102 35.3
High 178 24.3 92 20.7 86 29.8
Musculoskele al pain
No mul i-si e 321 43.7 191 42.9 130 45.0
Mul i-si e pain 413 56.3 254 57.1 159 55.0
21
Table 2: Risk a ios (RR) and 95% con idence in e al (CI) o mul i-si e pain in ela ion
o physical and men al s ain a wo k among he coho wi h no mul i-si e pain a baseline
(N=108), younge and olde employees
RR and 95% CI o mul i-si e pain
Model I Model II Model III
All
Physical s ain
Low 1.0 1.0 1.0
Medium 1.12 (0.81-1.55) 1.02 (0.70-1.48) 1.09 (0.74-1.60)
High 1.48 (1.01-2.18) 1.29 (0.83-2.00) 1.38 (0.87-2.18)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.22 (0.89-1.67) 1.27 (0.92-1.75) 1.14 (0.82-1.60)
High 1.19 (0.80-1.78) 1.28 (0.85-1.94) 1.23 (0.80-1.88)
Younge
Physical s ain
Low 1.0 1.0 1.0
Medium 1.20 (0.79-1.82) 1.16 (0.71-1.91) 1.40 (0.82-2.41)
High 1.39 (0.80-2.41) 1.34 (0.72-2.47) 1.69 (0.88-3.25)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.14 (0.76-1.71) 1.17 (0.78-1.77) 1.05 (0.68-1.62)
High 0.90 (0.49-1.66) 0.99 (0.53-1.87) 1.08 (0.56-2.10)
Olde
Physical s ain
Low 1.0 1.0 1.0
Medium 1.11 (0.65-1.87) 0.93 (0.52-1.65) 0.91 (0.50-1.66)
High 1.53 (0.89-2.64) 1.18 (0.62-2.24) 1.12 (0.57-2.20)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.31 (0.79-2.17) 1.38 (0.82-2.30) 1.28 80.74-2.21)
High 1.36 (0.77-2.40) 1.46 (0.82-2.61) 1.39 (0.75-2.55)
Model I: C ude isk a io
Model II: Adjus ed o gende and occupa ional s a us
Model III: Adjus ed o model II + physical exe cise, BMI and wo k abili y a baseline

22
Table 3: Risk a ios (RR) and 95% con idence in e al (CI) o mul i-si e pain in ela ion
o physical and men al s ain a wo k among he coho wi h mul i-si e pain a baseline
(N=291), younge and olde employees
RR and 95% CI o mul i-si e pain
Model I Model II Model III
All
Physical s ain
Low 1.0 1.0 1.0
Medium 1.02 (0.74-1.41) 1.05 (0.73-1.50) 0.97 (0.66-1.42)
High 1.46 (1.04-2.04) 1.52 (1.02-2.24) 1.28 (0.85-1.94)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.44 (1.07-1.95) 1.45 (1.07-1.97) 1.40 (1.01-1.93)
High 2.07 (1.47-2.92) 2.24 (1.57-3.20) 1.90 (1.30-2.78)
Younge
Physical s ain
Low 1.0 1.0 1.0
Medium 1.00 (0.65-1.53) 1.03 (0.64-1.67) 0.97 (0.58-1.62)
High 1.57 (1.03-2.41) 1.63 (1.00-2.73) 1.40 (0.81-2.42)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.37 (0.93-2.01) 1.37 (0.93-2.01) 1.21 (0.80-1.84)
High 1.96 (1.24-3.10) 2.15 (1.33-3.45) 1.68 (1.01-2.83)
Olde
Physical s ain
Low 1.0 1.0 1.0
Medium 1.04 (0.64-1.71) 1.07 (0.62-1.83) 0.92 (0.51-1.65)
High 1.25 (0.72-2.17) 1.30 (0.70-2.41) 1.00 (0.52-1.93)
Men al S ain
Low 1.0 1.0 1.0
Medium 1.54 (0.94-2.53) 1.56 (0.94-2.56) 1.63 (0.96-2.78)
High 2.24 (1.33-3.77) 2.42 (1.41-4.15) 2.25 (1.27-3.98)
Model I: C ude isk a io
Model II: Adjus ed o gende and occupa ional s a us
Model III: Adjus ed o model II + physical exe cise, BMI and wo k abili y a baseline