Medication use by the driving population

PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 5: 255-261 (1996) ORIGINAL REPORT Medica ion Use by he D i ing Popula ion M. CARMEN DEL RIO 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, 47005 Valladolid, Spain SUMMARY This s udy in es iga ed pa e ns o medicine use among Spanish d i e s. The s udy was conduc ed in he all o 1993 on 1500 d i e s aged o e 16, all o whom comple ed acco dingly and hen e u ned he ques ionnai es. Among hose su eyed, 45.1% had used d ugs a leas once in he p e ious yea , while 17.3% o d i e s su eyed we e using medicines ch onically. Ch onic use s, he majo i y o whom we e emale and belonging o he olde age g oup, we e using an a e age o wo d ugs. Cen al ne ous sys em d ugs (21.7%), espi a o y sys em d ugs (19.2%), ca dio ascula sys em d ugs (14.9%) and alimen a y ac d ugs (14.3%) we e he mos equen g oups o medica ion used, O hose su eyed 76.5% who ook d ugs egula ly had ne e been wa ned by heal h p o essionals abou he e ec s o he medica ion use on d i ing skills. The s udy shows bo h how o en d i e s use medica ion as well as he need o in o m pa ien s and d i e s abou he e ec o medica ion on d i ing pe o mance. KEY WORDS - d ugs; d ugs and d i ing; a ic sa e y INTRODUCTION Road a ic acciden s ha e become an impo an heal h p oblem in de eloped coun ies and hei p e en ion has long been a p io i y issue. Undoub edly, alcohol consump ion is one o he main causes o oad a ic acciden s. Ne e heless, i is o en o go en ha o he subs ances, such as ce ain o ms o medica ion and illegal d ugs, impai psychomo o skills ela ed o d i ing.] The ela ion be ween d ugs, d i ing and oad a ic acciden s is a complex one. In labo a o y expe imen s he apeu ic doses o se e al d ugs ha e been shown o impai psychomo o skills ela ed o d i ing.2 Howe e , he e a e ce ain aspec s which need cla i ying. One is he ela ion be ween d ug concen a ion and d i ing impai - men ; ano he , he legal conside a ion o d ug le els simila o hose o alcohol, e ~.~ In addi ion, in o ma ion ela ing o he equency o d ug-use by d i e s and he pe cen age o people who d i e Add essee o co espondence: F. Ja ie Al a ez, Depa men o Pha macology and The apeu ics. Facul y o Medicine, Uni- e si y o Valladolid, 47005 Valladolid, Spain, el: +(34 83) 423077, ax: +(3483) 423022 and +(3483) 423073. while unde he in luence o psychopha maco- logical agen s is sca ce, and he igu es a ailable di e signi ican ly. Pe haps his may be a ibu ed o he di e si y o explo a o y me hods used in he cou se o he s udies unde aken; hese include mailed ques ionnai es, p esc ip ion eco ds, pe - sonal o elephone in e iews, e ~.~-~ Wha is mo e, d ugs ha e e y o en been ound in body luids among d i e s in ol ed in oad a ic acciden s . 4-8 I has ecen ly been es ima ed ha a leas 10% o all people killed o inju ed in oad acciden s we e using some kind o psycho opic medica ion ha could ha e been conside ed a con ibu o y ac o . This ep esen s a di ec cos each yea o he Eu opean Communi y o a leas 7 billion ECUs, 5000 dea hs and 150,000 inju ies.l0 Unde Eu opean Communi y Council Di ec i e 91/439/EEC, au ho i ies esponsible o he issuing o d i ing licences mus de e mine he applican 's lack o impai men due o hei use o alcohol, illegal d ugs and medicines," al hough he e exis di icul ies conce ning he implemen a ion o his Di ec i e. lo In mos coun ies in o ma ion abou medica ion use and oad sa e y is sca ce and incomple e, and CCC 1053-8569/96/040255-07 C 1996 by John Wiley & Sons, L d. Recei ed I I May 1995 Accep ed 13 Decembe 1995 256 M. C. DEL RIO AND F. J. ALVAREZ he p esen na ional s udy was ca ied ou on a sample o Spanish d i e s wi h a iew o analysing he pa e ns o medica ion used by his sec ion o he popula ion, and how he use o medica ion could impai d i ing abili y. Conside a ion has also been gi en o he in o ma ion ecei ed by heal h p o essionals conce ning he e ec o medica ion on d i ing pe o mance, he eby acil- i a ing he p oposal o measu es as ega ds oad sa e y. The s udy also analyses heal h s a us, illegal d ugsI2 and alcohol cons~mp ion,’~ he esul s o which ha e been published elsewhe e. and e u ned. All he ques ionnai es we e checked o comple eness and accu acy. O hese, 1500 we e p ope ly comple ed. Fu he ques ionnai es ecei ed (220 by mid- 1994) we e no conside ed o analysis. O he mailed ques ionnai es, 2405 we e sen back by mid-1994 because a w ong add ess was gi en. The 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 6.07 e sion (unde he VAX/VMS 5 e sion). RESULTS METHODS The ques ionnai e used included, among o he i ems, sociodemog aphic da a and pa e ns o medicine use and d i ing. D i e s we e asked abou he medicines hey had used in he p e ious yea and we e using a p esen (when he su ey was ca ied ou ). All he in o ma ion pe aining o he medica ion (up o se en di e en d ugs) was eco ded: in each case hey we e asked abou he egis e ed name o he medicine hey we e using, he easons o using i , he in ake du a ion, and whe he he medicine used was o e - he-coun e o medically p esc ibed. Each egis e ed pha ma- ceu ical p epa a ion was coded ollowing he Ana omical The apeu ic Chemical classi ica ion sys em.I4 Ch onic d ug use was assessed among hose su eyed who, a he ime o he s udy, we e using medica ion. Ch onic o egula use was de ined as when he pe son conce ned had been using he d ug on a daily basis o a leas 1 mon h. The Summa y o P oduc Cha ac e i~ ics’~ o each medica ion was e iewed, and i was s a ed whe he o no he e was a wa ning abou he e ec o he medica ion on he abili y o d i e o use machine y. Those who d ank a leas once a weekI3 we e e med cu en alcohol d inke s. The a ge popula ion we e hose membe s holding a d i ing licence. A sample o 12,000 d i e s was andomly selec ed (by age g oup and sex) om he Na ional O icial Regis e o Spanish D i e s. The sample size selec ion was based on esponse igu e a es ob ained om his egis e , and he aim was o ob ain a inal sample o a leas 1500 indi iduals. The ques ionnai e, wi h ins uc ions o comple- ion, we e mailed o selec ed d i e s be ween 26 Sep embe and 15 Oc obe 1993. By 15 Decembe o ha yea , 1598 ques ionnai es we e comple ed The esponse a e (1720 ou o 12,000: 14.3%) was as expec ed, and simila o ha ob ained ea lie om his egis e (1116 ou o 8200: 13.6%). Howe e , we mus ecognize ha his is a e y low a e when compa ed wi h hose ob ained in o he de eloped coun ies. The easons o his could be: (i) he complexi y o he ques ionnai e, dealing wi h in o ma ion on ma e s as di e se as heal h s a us, use o medica ion, alcohol and illegal d ugs. The e o e, comple ion o he ques ionnai e could be di icul o some people wi h a low edu- ca ion le el. (ii) As i was clea ly indica ed in he ques ionnai e ha he s udy was being ca ied ou by he Na ional T a ic Agency, many d i e s could ha e been discou aged om answe ing he ques- ionnai e. (iii) Possibly, ye mos p obably, he ac ha in he o icial egis e o Spanish d i e s a g ea numbe o add esses a e inco ec , al hough e e y d i e s should, acco ding o law, gi e no i ica ion o any change in add ess. The said egis e is used o no i ica ion o sanc ions and ines; a w ong add ess in he egis e p e en s he d i e om being no i ied, and p esc ip ion ensues i , a e a ce ain leng h o ime, he d i e is no This s udy is based on 1500 d i e s who, as has al eady been s a ed, comple ed he ques ion- nai e.I2-l3 The sample dis ibu ion o esponden s (by age g oup and sex) did no di e (p > 0.05) om ha o all Spanish d i e s. Table 1 shows he gende dis ibu ion o he sample as ega ds hei sociodemog aphic cha ac e is ics. The sample could no be compa ed wi h he en i e d i ing popula ion on addi ional a iables because he o icial egis e o Spanish d i e s has in o ma ion ega ding only age, sex, ype o d i ing licence and add ess. O he Spanish d i e s su eyed, 45.1 YO (676 ou o 1500, Table 2) had used d ugs a leas once in he 0 1996 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY. VOL. 5: 255-261 (1996) MEDICATION USE BY SPANISH DRIVERS 257 Table 1 -Sociodemog aphic cha ac e is ics o he d i ing popula ion su eyed Male Female n YO n YO To al 1016 67.7 484 32.3 Age ange 16-20 21-30 31-40 41-50 5 1-60 61-70 > 70 Ma i al s a us Single Ma ied Di o cee Widowed Educa ional le el No schooling P ima y Middle Seconda y High Uni e si y 88 27 1 26 1 180 133 70 13 363 62 1 20 12 11 175 212 264 115 200 8.6 51 26.7 213 25.7 119 17.7 73 13. I 26 6.9 1 1.3 1 35.7 259 61.1 193 2.0 22 1.2 10 1.1 3 17.9 40 21.7 78 27.0 150 11.8 83 20.5 120 10.5 44.0 24.6 15.1 5.4 0.2 0.2 53.5 39.9 4.5 0.1 0.6 8.4 16.5 31.6 17.5 25.3 pe ious yea (43.4% among males and 48.5% among emales, p < 0.05). As ega ds he numbe o medicines, mos o hem had used ei he one (58.0%) o wo (28.8%). Th ee o mo e d ugs we e used by 13.2%. O d i e s su eyed, 17.3% (259 ou o 1500 su eyed, Table 2) we e using medicines ch onic- ally (16.9% o males and 18.0% o emales, p < 0.05), and, he olde he indi idual he mo e Table 2-Pa e ns o medica ion use by Spanish d i e s common his phenomenon was. O hese, 39% we e using one d ug, 39% wo d ugs, and 22% we e using h ee o mo e d ugs. Each o hese indi iduals (n = 259, 5 1 1 d ugs, Table 2) was using an a e age o 1.97 k 1.10 (mean SD) medicines (1.87k0.98 o males - n= 172, 323 d ugs - and 2.16 1.29 o emales - n = 87, 188 d ugs, p = 0.0506). The ou mos common ch onically used g oups o d ugs (Table 3) we e cen al ne ous sys em d ugs (21.7%), espi a o y sys em d ugs (19.2%), ca dio ascula sys em d ugs (14.9%) and d ugs o he alimen a y ac and me abolism (14.3%). Table 3 shows also he gende dis ibu ion ega d- ing he medicines used. Fo 26.4% (Table 3) o he medica ion used ch onically (135 ou o 51 1) he e was a wa ning in he Summa y o P oduc Cha ac e is ics abou he e ec o he medica ion on he abili y o d i e and he sa e use o machine y. Mos medica ions supplied wi h his wa ning a e ca dio ascula sys em d ugs (29.6%), cen al ne ous sys em d ugs (3 1.1 YO) and espi a o y sys em d ugs (22.2%). This da a shows ha 4.6% o d i e s (26.4% o he d ugs aken ch onically by 17.3% o he popula ion) we e using medica ion ha impai s d i ing pe o mance. Table 3 also shows egis e ed d ugs in Spain, as well as hose wi h a wa ning conce ning he e ec o he medica ion on d i ing abili y (503 ou o 3720: 13.5%). Among all hose su eyed, 62.9% (943 ou o 1500) we e cu en alcohol d inke s,') and 64.5% (167 ou o 259) we e among hose who ook medicines egula ly. Only 21.6% o hose using medicines (56 ou o 259) admi ed no ha ing consumed alcohol when using medicines. I was Sample dis ibu ion Medica ion use in pas yea Ch onic use o medica ion n n YO n YO To al 1500 676 45.1 259 17.3 Sex Male 1016 Female 484 16-20 139 21-30 484 3 1-40 380 41-50 253 51-60 159 61-70 71 > 70 14 Age ange x2 = 3.5 p < 0.05 x2 = 0.25 p < 0.05 441 43.4 172 16.9 235 48.5 87 18.0 66 47.5 235 48.5 157 41.3 105 41.5 70 44.0 38 53.5 5 35.7 28 20.1 66 13.6 50 13.2 42 16.6 40 25.2 28 39.4 5 35.7 0 1996 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY. VOL. 5: 255-261 (1996) 0 5 Y 6 Table 3 - Types o medica ion used by Spanish d i e s, and wa ning abou medica ion used and d i ing abili y Ana omical The apeu ic Chemical Medica ion used Regis e ed medica ion classi ica ion sys em Ch onic use in Spain Pas yea To al Male Female Wa ning* To al Wa ning* n YO n% n YO n YO n YO n% n Alimen a y ac and me abolism 125 11.4 73 14.3 55 17.0 18 9.6 8 5.9 748 103 13.8 Ca dio ascula sys em 76 6.9 76 14.9 63 19.5 13 6.9$ 40 29.6 294 116 39.4 Blood and blood o ming o gans 27 2.5 27 5.3 7 2.2 20 10.6$ 1 0.7 350 3 0.8 De ma ologicals 7 0.6 4 0.8 2 0.6 2 1.1 0 0.0 386 0 0.0 Geni o-u ina y sys em and sex 22 2.0 19 3.7 6 1.9 13 6.9$ 1 0.7 143 7 4.9 ho mones excluding sex ho mones 8 0.7 5 1.0 3 0.9 2 1.1 52 1 1.9 0 0.0 An ineoplas ic and immunomodula ing 0 0.0 0 0.0 0 0.0 0 0.0 57 0 0.0 0 0.0 Sys emic ho monal p epa a ions, Gene al an iin ec i es o sys emic use 164 14.9 43 8.4 26 8.0 17 9.0 6 4.4 287 31 10.8 agen s Musculoskele al sys em 59 5.4 34 6.6 19 5.9 15 8.0 7 5.2 159 18 11.3 Cen al ne ous sys em 331 30.2 111 21.7 65 20.1 46 24.5 42 31.1 357 129 36.1 An ipa asi ic p oduc s 0 0.0 0 0.0 0 0.0 0 0.0 13 1 7.7 0 0.0 Respi a o y sys em 238 21.7 98 19.2 65 20.1 33 17.6 30 22.2 548 88 16.0 Senso y o gans 10 0.9 6 1.2 6 1.9 0 0.0 0 0.0 212 4 1.9 Va ious 30 2.7 15 2.9 6 1.9 9 4.8 0 0.0 114 2 1.7 To al sample 1097 100.0 511 100.0 323 100.0 188 100.0 135 26.4 3720 503 13.5 ~~~~~ ~~ *The e is a wa ning abou he e ec o he medica ion on he abili y o d i e o use machine y in he Summa y o P oduc Cha ac e is ics.'4 Chi-squa e male compa ed o emale: p < 0.05, $p < 0 005. P 5 MEDICATION USE BY SPANISH DRIVERS 259 no common o hose su eyed (5.8%, n = 15; 4.6%. n = 8 o males, and 8.O%, n = 7 o emales, x2 = 1.22, p < 0.05) o epo ha he medica ion used egula ly a ec ed hei d i ing pe o mance. Su eyed d i e s who ook d ugs egula ly we e asked i hey had been wa ned by heal h p o- essionals abou he e ec s o he medica ion used on d i ing skills: o hese, 76.5% had ne e been wa ned, 19.4% had been wa ned on some occasions, and 4.1 YO had equen ly been wa ned. Simila igu es (x2 = 0.24, p < 0.05) we e ound be ween sexes (ne e : 75.6% males and 78.5% emales; some occasions: 20.1% males and 17.7% emales; equen ly: 4.3% males and 3.8% emales). DISCUSSION The p esen s udy shows a se ies o in e es ing da a, he i s o which is ha medicines a e equen ly used by he popula ion. Ce ain medica ions ha e been used by 45.1 YO du ing he las yea and 17.3% use hem ch onically. I has o be poin ed ou ha among egula use s, he majo i y ake an a e age o wo medica ions. Ano he ema kable ac is he equency o join use o alcohol and medica ion. Finally, and wha is mo e impo an , is ha in h ee ou o ou cases conce ning egula d ug use s, heal h p o essionals do no p o ide he pa ien wi h any in o ma ion as ega ds he e ec o he medica ion on d i ing abili y. A compa ison wi h he da a ob ained in o he s udies is di icul , due o a lack o s anda diza ion and he di e en ypes o me hodology used. Fo ins ance, a s udy among he Aus ian popula ion e ealed ha d ug in ake was epo ed by 44% in he 3 mon hs p io o he in e iew, and 27% in he p e ious week; u he mo e, he a e age numbe o d ugs used was 1 .84.5 In a F ench s udy on ic ims o oad a ic acciden s, 23.6% admi ed ha ing aken medica ion 5 days be o e he acciden .6 In a Finnish s udy on casual ies a ending eme gency depa men s, 31.6% said ha hey had used some medica ion a week ea lie , whils 15.3% admi ed ha ing used some medica ion a week p io o he a~ciden .~ In he Uni ed Kingdom, he equency wi h which medicines a e used among samples o he gene al d i ing popula ion anges om 5.5% o 22%; o hose medica ions likely o ha e an e ec on he cen al ne ous sys em, he equency is be ween 2% and 5%.8 The p esen s udy also shows ha hese people o en use a ious ypes o medica ion a he same ime: 61% use wo o mo e ypes o medica ion. This makes in e ac ions mo e common and, conse- quen ly, causes a g ea e de e io a ion o psycho- mo o pe o mance in ce ain cases. Wha is no su p ising, gi en he ac ha alcohol is usually consumed in many Eu opean coun ies, is ha alcohol consump ion among he d i e s su eyed is equen : 62.9% among all hose su eyed and 64.5% among hose who usually use medica ion; his con i ms he p e ious inding~.'~ A ac o be conside ed, is ha consuming alcohol and using medica ion ha e nega i e e ec s on psychomo o pe o mance, and, as a esul , he e is a g ea e acciden isk. Wha is mo e, i is app op ia e o men ion ha only a small numbe o hose who no mally use medica ion (5.8%) admi ha ha medica ion a ec s hei d i ing pe o mance. Wi hin he Eu opean communi y, package inse s include a s a emen ega ding he e ec s o medica ion on he abili y o d i e o use machine y." Fu he mo e, he e has ecen ly been accep ed a h ee- ie wa ning sys em o iden i y he haza d po en ial o d ugs on d i ing abili y in he Summa y o P oduc Cha ac e is ics." The e is a s a emen conce ning medica ion e ec s on he abili y o d i e among 26.4% o ch onically used ypes o medica ion (4.6% o all su eyed). This is impo an , and i is logical o hink ha hese indi iduals migh expe ience impai men o ce ain o he acul ies needed o sa e d i ing. Howe e , al hough he da a do no pe mi us o s a e whe he hese people we e in he habi o d i ing unde he in luence o medica ion, hey do demons a e he equency wi h which medica ion ha could impai d i ing pe o mance is used. Fu he mo e, among all egis e ed medica ions in Spain, 13.5% con ain a wa ning ega ding hei e ec on d i ing abili y. Age and sex a e among he majo ac o s in luencing he le el o d ug use:16 elde ly and emale a e he mos common cha ac e is ics o d ug use s. In he p esen s udy, ch onic use o medica ion is mo e common among he aged popula ion, while no signi ican di e ences we e ound be ween sexes (al hough he igu es o women we e highe han hose o men). The eason could be ela ed o he ac ha mos emale d i e s in Spain belong o he younge age g oups. In 1993 he e we e abou 15,882,000 d i e s in Spain, men (67.3%) a e mo e han wice as likely han emales (32.7%) o be d i e s. Finally, and mo e signi ican ly, in 76.5% o cases, heal h p o essionals ha e ne e wa ned hei pa ien s abou he e ec o medica ion on d i ing 0 1996 by John Wiley & Sons, L d. PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, VOL. 5: 255-261 (1996) 260 M. C. DEL R10 AND F. J. ALVAREZ pe o mance. This inding coincides wi h he da a encoun e ed in p e ious s udies.17 In spi e o p oduc in o ma ion and labelling, we belie e'' ha heal h p o essionals - doc o s and chem- is s - should gi e ad ice o hei pa ien s abou he ex en o which he medica ion p esc ibed (as well as illness and alcohol consump ion) migh in e e e wi h hei d i ing abili y. The p esen s udy is no wi hou se e al limi a ions (a low esponse a e, i s desc ip i e na u e, e c.), bu i does highligh he la ge numbe o d i e s using medica ion ha could impai d i ing pe o mance. E en so, we will admi ha some possible a ia ions in he ga he ed in o ma- ion could exis , because we canno exclude o e - o unde epo ing medica ion use. The e is a need o s anda dize he me hodology employed in his ield,lg in o de o cha ac e ize he ex en o his phenomenon. In he las ew yea s, no only ha e legisla i e ules been in oduced, bu special a en ion has been de o ed o assessing he isk o being in ol ed in a a ic acciden while d i ing a e using medica ion. Se e al s ~dies'~-~' ha e shown he inc eased isk o being in ol ed in a oad acciden when d i ing unde he in luence o some medica ion, mainly psycho opic medica ion. The ull impac o medica ion on d i ing is di icul o es ablish, bu i is easy o accep ha some kinds o medica ion in e e e wi h d i ing pe o mance and, he e o e, could inc ease he isk o oad acciden s.' Road acciden s ep esen one o he main public heal h p oblems wo ldwide, and he need o de elop policies gea ed owa ds hei educ ion is becoming mo e and mo e u gen . The ole o medica ion as ega ds oad sa e y should no be o go en. Doc o s should be awa e o he possible in luence o he medica ion p esc ibed on d i ing pe o mance, and should in o m hei pa ien s abou i . 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