The use of medication by the Spanish population

ORIGINAL REPORT The Use o Medica ion by he Spanish Popula ion M. CARMEN DEL RIO MD, CARLOS PRADA MD AND F. JAVIER ALVAREZ MD Depa men o Pha macology and The apeu ics, Facul y o Medicine, Uni e si y o Valladolid, Valladolid, Spain SUMMARY The aim o he s udy was o assess pa e ns o he use o medicines by he gene al popula ion olde han 0 yea s. The s udy was based on he in o ma ion con ained in he compu e ized da abase om he 1993 Spanish Household Heal h Su ey. A ep esen a i e sample o he popula ion olde han 0 was iden i- ®ed, and a su ey o 26,334 pe sons was ca ied ou . O he popula ion 45.3% had aken some medicine in he las 2 weeks p io o he ca ying ou o he su ey. The p opo ion was g ea e o women (50.6%) han o men (39.6%). Wi h inc easing age, he equency and amoun o medica ion use inc eased. A li le o e 20% o he medicines used we e no p esc ibed by a doc o (sel -medica ion). Da a show he equency o he use o medicines by he Spanish popula ion. #1997 by John Wiley & Sons, L d. Pha macoepidemiology and D ug Sa e y 6: 41±48, 1997 No. o Figu es: 2 No. o Tables: 3 No. o Re s: 22 KEY WORDS Ð d ug u iliza ion ends; sel -medica ion; age ac o s; sex ac o s; adul ; child; gene al popula ion INTRODUCTION The as numbe o comme cialized d ugs, he g ea amoun o medica ion used, and he a ion- ali y o such use ha e become majo conce ns o he public heal h au ho i ies in many indus ialized coun ies in he las ew yea s.1 ± 3Rela ed o medica ion use, quali a i e aspec s a e as impo - an as quan i a i e ones: how a e hese medicines used? Wha posi i e o nega i e eec s do hey ha e on heal h in he communi y? e c. Quali a i e d ug u iliza ion s udies p o ide use ul in o ma ion allowing us o de elop s a e- gies leading o a mo e a ional use o medica ions. Howe e , he majo i y o published d ug u iliza- ion s udies a e based on in o ma ion de i ed om sales and p esc ip ions;1 ± 3d ug u iliza ion s udies based on a consume app oach a e a e, despi e he g ea amoun o in o ma ion hey p o ide. The need o s anda d me hodology in d ug u iliza ion s udies has al eady been acknowledged.4In ecen yea s, i has been poin ed ou ha a comple e assessmen o d ug use should also ake he social aspec s in o accoun .5 Consequen ly, he aim o his s udy has been he cha ac e iza ion o he use o medicines among he popula ion om ze o yea s o age onwa ds, he basis being he 1993 Spanish Household Heal h Su ey. Spain has a popula ion o abou 38 million, and he Na ional Heal h Se ice co e s nea ly all o he popula ion.6Since he 1970s, he D ug Regula o y Au ho i y has e iewed Spanish pha maceu ical p oduc s, hus ensu ing he e- cacy, sa e y and quali y o he a ailable medicines as a ® s s ep owa ds he a ional use o d ugs. One o he ac i i ies de eloped was he `P ose eme p og amme', h ough which all pha maceu ical p oduc s we e e iewed and many medicines we e wi hd awn o hei o mula ions al e ed.6A s udy ca ied ou in 19817showed ha 41% o he Add essee o co espondence: F. Ja ie Al a ez, Depa - men o Pha macology and The apeu ics, Facul y o Medi- cine, Uni e si y o Valladolid, 47005 Valladolid, Spain, ax: (34 83) 423073 and (34 83) 423022. CCC 1053±8569/97/010041±08$17.50 Recei ed 20 No embe 1995 #1997 by John Wiley & Sons, L d. Accep ed 2 Augus 1996 PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) medica ion used in ha yea was o high po en ial alue; 12% o ela i e alue; 25.5% o doub ul o no alue, and 21.4% was a ed as unaccep able. Fo una ely, in ou opinion, he p esen si ua ion has la gely changed. In he las ew yea s special eo s ha e been made o educe medica ion cos s o he Na ional Heal h Se ice, as well as p omo ing a ional medica ion use.8The la es ®gu es show ha medi- ca ion cos s ha e inc eased yea by yea , om 178,348 in 1984 o 641,701 in 1994 (®gu es in million pese as, 125 pese as abou 1 US dolla ). The numbe o p esc ip ions inc eased be ween 1984 (432 million p esc ip ions) and 1992 (519), and hen dec eased in 1993 (506) and 1994 (494). Se e al da abases, basically ela ed o he p esc ibed d ugs h oughou he Na ional Heal h Se ice and hei cos , a e cu en ly a ailable in ou coun y.6These ha e been used in he pe o mance o d ug u iliza ion s udies. Howe e , assessmen o he social aspec s o medica ion use by Spania ds has no unde gone he same amoun o esea ch. METHODS The s udy was based on in o ma ion con ained in he compu e ized da abase o he Spanish House- hold Heal h Su ey ca ied ou by he Spanish Minis y o Heal h in 1993.9The wo k was unde he auspices o he Subdi eccio Ân Gene al de In o macio Ân Sani a ia y Es adõÂs icas Sani a ias. The ®eld wo k and eco ding o he in o ma ion was ca ied ou by he Cen o de In es igaciones Sociolo Âgicas. The aim o he su ey was o ob ain in o ma ion conce ning he aspec s ela ed o heal h and he use o heal h esou ces, including he use o medica ions. A su ey o 26,334 people (21,084 adul s and 5,250 child en unde 16 yea s o age) who we e a ep esen a i e sample o he non-ins i u ionalized Spanish popula ion olde han 0 yea s, was ca ied ou . The sample was designed o be ep esen a i e bo h a na ional and Au onomous Communi y (Regional) le el. The sampling e o , wi h a con®- dence le el o 95.5%, was 0.8%, 0.9% in he case o adul s and 1.8% in he case o child en. A complex mul is age sample design was used. I was designed as ollows: ® s , by he Spanish communi ies ( he e a e 17 Au onomous Comm- uni ies plus Ceu a and Melilla, comp ising a o al o 52 p o inces); second, by se en s ages acco ding o he numbe o inhabi an s: 52000 (n2249), 2001±10,000 (n4510), 10,001±50,000 (n6110), 50,001±100,000 (n2231), 100,001± 400,000 (n6160), 400,001±1,000,000 (n1715) and 41,000,000 (n3329), (missing n29); hi d, by ci ies in each one o he communi ies, and ®nally, by age g oup: 1±10 yea s (n3350), 11±20 (n4176), 21±30 (n4228), 31±40 (n3564), 41±50 (n3147), 51±60 (n2971), 61±70 (n2805), 470 (n1745) (missing n348), and by gende (males, n12,862; emales, n13,416; missing n56). Ques ionnai es we e comple ed by di ec in e - iew wi h selec ed people. The ques ionnai es we e adminis e ed by ained in e iewe s. Rega ding he child en, he ques ionnai e was answe ed by hei a he , mo he o gua dian. When a pe son selec ed was una ailable o unwilling o be in e - iewed a eplacemen was chosen. Al hough he ques ionnai es we e die en in bo h age g oups (adul s and child en), hey bo h included i ems ela ing o medica ion use. Those su eyed we e asked: (i) i hey had aken any kind o medicine in he las 2 weeks, (ii) i so, wha kind o medicine hey had aken (using 17 die - en he apeu ics ca ego ies among adul s, and 11 in he case o child en), (iii) o each ype o medica ion, i he medicine used was p esc ibed by a doc o o no ( he la e case, was conside ed as sel -medica ion). Analysis o he da a was ca ied ou in he Da a P ocessing Cen e a Valladolid Uni e si y, using he s a is ical package SAS (Ve sion 6.07). pValues 40.05 we e conside ed o show signi®- can die ences. RESULTS O he Spanish popula ion 45.3% had used some kind o medica ion in he wo p e ious weeks (Fig. 1), 39.6% we e men and 50.6% women 2 1314.10, p<0.0001). These die ences also exis in he adul g oup (40.5% o men and 53.2% o women, 2 1332:71, p<0.0001), bu no in he child en's age g oup (516 yea s o age): 36.4% o boys and 39.8% o gi ls 2 16.25, p>0.05). F om he 11±20 age g oup, he equency o medicines used inc eased wi h age (Fig. 1). This end was obse ed in bo h men and women. The a e age numbe o medicines used (Fig. 2), inc eased in he 11±20 yea s age g oup, he inc ease being g ea e o women (1.50+0.65, mean+SD) han o men (1.38+0.72; F85.02, p<0.0001). I we analyse he numbe o medicines used (one, wo, 42 M. C. DEL RIO, C. PRADA AND F. J. ALVAREZ #1997 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) h ee o mo e) pe age g oup (Fig. 2), i is clea ha , om he 11±20 age g oup, he aking o only one medicine dec eased wi h age, wi h he aking o wo, h ee o mo e medicines inc easing in a pa allel way. Wi h ega d o sex, die ences we e obse ed (2 284.59, p<0.0001): men ake only one medicine (71.4%) mo e equen ly han women (63.8%), while women ake wo (22.6%), h ee o mo e (13.7%) medicines a a g ea e a e pe cen age-wise han men (19.4% and 9.2%). The e we e die ences in medicine used among adul s depending on ce ain sociodemog aphic a iables (Table 1): medicine use was mo e equen he g ea e he size o he popula ion; use was also mo e equen among hose who we e widows, people wi h no schooling and he e i ed. These ends a e ound among bo h sexes. In he adul popula ion su eyed (Table 2), he mos equen g oups o d ugs aken we e es- pi a o y p oduc s (14.9%), analgesics/an ipy e ics (10.8%) and hypo ensi es (7.8%). In mos g oups, he use o medicine was mo e common among women. Gas oin es inal p epa a ions we e mo e equen ly used by men. No die ences exis ed be ween he sexes in espec o espi a o y p oduc s, ca diac he apy, and an ialle gic p o- duc s. O he medicines used 23.4% we e no p esc ibed by a doc o (sel -medica ion). Fo men his pe cen age was 25.7% and o women 21.9% (2 128.50, p<0.0001). The g oups o d ugs in which sel medica ion was g ea e we e: an i- obesi y, laxa i es, analgesics/an ipy e ics, and espi a o y p oduc s (Table 2). One ou o ou child en polled, had used espi a o y p oduc s (Table 3). The e we e die - ences be ween sexes only in he espi a o y p oduc s, which we e mo e equen ly used by boys (4.9%) han gi ls (4.2%). Among child en 20.6% o he medicines used we e no p esc ibed by a doc o (sel -medica ion), 20.1% o boys and 21.1% o gi ls (2 10.38, p>0.05). The g oups o medicines in which sel -medica ion was 43 THE USE OF MEDICATION IN SPAIN #1997 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) Fig. 1 Ð Medica ion use by he popula ion mo e equen we e he analgesics, an ipy e ics, laxa i es, anquillize s and hypno ics. DISCUSSION The esul s ob ained show he equency o he use o medicines among he popula ion. Abou 45% o hose su eyed had used some kind o medicine du ing he p e ious 2 weeks. One o he mos impo an ac o s in¯uencing he le el o d ug use is age. Da a10;11 consis en ly indica e ha he elde ly use mo e d ugs han younge age g oups. S a ing om he 11±20 age g oup, a p og essi e inc ease in equency and numbe o medicines used is obse ed, because mo bidi y inc eases wi h age. Ano he in¯uencing ac o , al hough less impo an han age, is sex. Women no only use medicines mo e equen ly han men, bu also ake mo e o hem. Visi s o he doc o a e also mo e common among women han men. Simila da a a e ound in o he s udies.10;12 O he demog aphic ac o s which in¯uence he use o medicines a e: ma i al s a us, educa ional backg ound, wo k si ua ion and size o he com- muni y o which one is a membe . The widowed and e i ed use medicines mo e equen ly, which is p obably due o hei g ea e age and mo bidi y. Those people wi h no schooling o wi h only p ima y educa ion use a g ea e amoun o medicines. When conside ing popula ion size, a clea inc ease in he equency o medicine use is obse ed when he size o he communi y is bigge . 44 M. C. DEL RIO, C. PRADA AND F. J. ALVAREZ #1997 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) Fig. 2 Ð Numbe o medica ions consumed by he popula ion The impac o socio-economic s a us on he aking o d ugs is also e iden .11 O he s udies10 ha e shown ha he accessibili y o heal h se ices, eimbu semen sys ems, e c., may also play a pa in he le el o d ug use. The a ailabili y o a doc o is essen ial in ob aining a p esc ip ion, and mos consul a ions lead o a p esc ip ion. As ega ds he he apeu ic g oups used, ou da a should be accep ed wi h cau ion, mainly because: (i) du ing he pe iod o he su ey (Feb ua y), he use o ce ain medicines was mo e equen , and (ii) hose su eyed we e asked only abou ce ain classes o d ugs used, in some cases abou e y speci®c he apeu ic g oups (e.g. laxa i es) and in o he s abou a wide ange o d ugs (e.g. medica ion o he alimen a y ac ). This is due o he ac ha , in o de o make i easy o he use o unde s and, colloquial language has been used, and ques ions ha e been asked ega ding he a- peu ic ca ego ies which can be iden i®ed easily. Undoub edly, in o ma ion ob ained om o he sou ces, such as wholesale da a, may be mo e accu a e. Figu es om wholesale da a o 1991 show ha he mos equen ly p esc ibed d ugs we e: cen al ne ous sys em d ugs (17.8%), espi a o y p oduc s (16.8%), alimen a y ac (16.4%), and ca diac he apy (9.7%). In addi ion, he e a e die ences in he p esc ip ion o ce ain medicines be ween coun ies (e.g. benzodiaze- pines).13 Acco ding o ou da a, one ou o ® e medicines used in he p e ious 2 weeks, bo h among adul s and child en, was no p esc ibed by a doc o . One o he g oups o d ugs in which sel -medica ion is g ea es is ha o analgesics and an ipy e ics. These da a acco d wi h hose ob ained in o he s udies.14 Two comple ely die en si ua ions a e in ol ed in sel -medica ion. Fi s ly, he use o medicines which, he Spanish legisla ion s ipula es, should be medically p esc ibed, bu which hose su eyed ob ained wi hou medical p esc ip ion: his is he case o anquillize s and hypno ics, an i- dep essan s, con acep i es, hypo ensi es, e c. This ype o sel -medica ion is equen among he Spania ds as a as ou s udy is conce ned, and shows ha in ou socie y he egula ions dealing wi h he dispensing o medica ion a e no s ic ly adhe ed o. In addi ion, he e exis s he use o o e - he-coun e p epa a ions, such as ce ain laxa i es, i amins, analgesics and an ipy e ics, e c. Logically, hese wo ypes o sel -medica ion ha e comple ely die en consequences om he heal h poin o iew. The inc easing o e - he-coun e d ugs and he implica ion o pa ien s, gene al p ac i ione s and pha macis s, ha e been g ea ly discussed in he las ew yea s,15 and emphasis has been placed on he need o p omo e adequa e and p ope use o hese p epa a ions. This s udy is subjec o ce ain limi a ions when i comes o cha ac e izing pa e ns conce ning medica ion use. Apa om he abo e-men ioned he apeu ic g oups selec ed, he e is no in o ma- ion a ailable wi h ega d o he ype o subs ance used, no he eason o i s p esc ip ion. Fu he - mo e, he e is no knowledge o how long he sub- s ance was used o , no he doses adminis e ed. Ce ain o hese limi a ions a e common o o he s udies in he gene al popula ion.16 In addi ion, compa ison wi h ®gu es om o he coun ies is dicul , since in he Na ional Heal h Su eys, he e is ei he no inclusion o ques ions 45 THE USE OF MEDICATION IN SPAIN #1997 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) Table 1 Ð D ug use by adul s: sociodemog aphic cha ac e is ics To al Male Female (%) (%) (%) Popula ion size* 52000 40.8 34.0 47.2 2001±10,000 43.5 35.5 50.9 10,001±50,000 45.9 40.0 51.7 50,001±100,000 46.5 39.9 52.8 100,001±400,000 46.8 40.3 52.9 400,001±1,000,000 53.1 47.4 58.5 41,000,000 55.9 50.4 60.8 Ma i al s a us* Single 35.4 30.6 41.7 Ma ied 49.5 45.2 53.6 Di o cee 48.6 44.8 50.8 Widowed 74.1 62.2 76.6 Educa ional s a us* No schooling 66.8 56.5 72.9 P ima y 45.9 39.5 51.5 Secunda y 37.3 33.3 42.2 High 41.4 39.4 43.8 Uni e si y 42.9 41.8 44.3 Occupa ional s a us* Wo k 36.8 33.6 43.8 Re i ed 72.5 68.9 77.6 Unemployed 39.3 33.7 46.4 S uden 34.0 30.3 37.8 Housewi e 55.4 38.0 55.5 *p<0.0001 (2). ega ding medica ion, o hese e e o speci®c he apeu ic g oups. Fo example, in Canada's Heal h P omo ion Su ey,17 hose su eyed we e asked i in he pas 12 mon hs hey had used (i) sleeping pills (ii) pep pills, s imulan s, o (iii) anquilize s such as alium; in he 1993 Swiss Heal h Su ey,18 ques ions we e asked abou he use o sleeping pills and anquilize s in he 7 days p eceding he in e iew. Howe e , in he Heal h Su ey o England,19 (a se ies o annual su eys designed o moni o ends in he na ion's heal h), as pa o he nu se- isi , in o ma ion was collec ed 46 M. C. DEL RIO, C. PRADA AND F. J. ALVAREZ #1997 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 6: 41±48 (1997) Table 2 Ð Class o medica ion used by he Spanish adul popula ion Medica ion To al Male Female Sel -medica ion % % % % An i heuma ics* 4.8 2.9 6.6 6.8 Respi a o y p oduc s 14.9 14.8 15.0 35.2 Analgesics and an ipy e ics* 10.8 8.1 13.3 45.2 Vi amins* 2.9 2.2 3.5 27.3 Ca diac he apy 3.3 3.4 3.2 5.4 Hypo ensi es* 7.8 5.5 10.0 6.7 Laxa i es* 1.4 0.6 2.0 50.0 Alimen a y ac * 3.3 3.7 2.9 16.3 T anquillize s and hypno ics* 4.2 2.7 5.6 15.6 An idep essan s* 1.5 0.9 2.0 17.7 An ibio ics* 2.0 1.7 2.3 19.7 Con acep i es* 1.2 0.0 2.3 21.0 An iobesi y* 0.3 0.1 0.5 51.4 An ialle gic p oduc s 1.3 1.2 1.4 12.7 Choles e ol educe s* 2.6 2.1 3.1 13.2 An idiabe ic he apy* 2.3 1.7 2.8 11.8 Va ious* 6.0 5.0 6.8 13.9 n21084 10176 10877 *p<0.005 (2). Figu es o sel -medica ion (non-medical p esc ip ion) e e o each class o medica ion. Please no e some pa ien s use mo e han one class o medica ion and hence he indi idual classes canno be added up o each he o al. Table 3 Ð Class o medica ion used by Spanish child en Medica ion To al Male Female Sel -medica ion % % % % Respi a o y p oduc s* 24.4 22.8 26.3 15.1 Analgesics 5.6 5.6 5.6 48.2 An ipy e ics 4.6 4.9 4.2 18.0 Vi amins 3.1 2.7 3.5 28.4 An ieme ics 0.6 0.6 0.5 20.5 An idia hoeals 0.8 0.6 1.0 26.0 Laxa i es 0.1 0.1 0.1 40.0 T anquillize s and hypno ics 0.4 0.4 0.4 29.9 An ibio ics 4.5 4.0 4.9 15.7 An ialle gic p oduc s 1.9 2.2 1.7 14.9 Va ious 2.7 2.9 2.6 17.0 n5250 2686 2539 *p<0.005 (2). Figu es o sel -medica ion (non-medical p esc ip ion) e e o each class o medica ion. Please no e some pa ien s use mo e han one class o medica ion and hence he indi idual classes canno be added up o each he o al. abou any p esc ibed medica ion he esponden was aking a he ime (las 7 days). The nu ses eco ded de ails o all medicines being aken om he medicine con aine s. The ends obse ed we e simila o hose ound by us. Abou 38% o adul s (o e 16) we e aking a leas one p esc ibed medicine, and hei use was ela ed o sex and age, as well as o epo ed gene al heal h and epo ed long-s anding illness o disabili ies. Al hough he e a e me hodological guidelines o su eys on heal h,20;21 hese a e lacking in he ®eld o medica ion use by he popula ion. P o ided hese limi a ions a e ecognized, i can be accep ed ha a emp s, such as his o ca y ou a su ey on medica ion use le els among he popula ion oe impo an in o ma ion which complemen s o he d ug u iliza ion s udies; o ins ance, sales and p esc ip ions. To gi e examples, such s udies enable us o unde s and he e e - inceasing use o d ugs, he sociodemog apic ac o s which ela e o hei use, he join use o d ugs and alcohol,22 he magni ude o sel -medica ion, e c. The eqen use o medicines has led o he need o de ise s a egies encou aging a ional use. 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