Prevalence and Associated Factors of Drug-Related Problems Among Older People: A Cross-Sectional Study at King Chulalongkorn Memorial Hospital in Bangkok

Background and ObjectiveThe use of multiple medications and altered pharmacokinetics/pharmacodynamics may lead to drug-related problems in members of the older population. The aim of this study is to evaluate the prevalence of, and factors related to, drug-related problems in older urban-living Thai people.MethodsWe conducted a cross-sectional study involving 466 participants (aged >= 65 years) whose first-time health screening at the Geriatric Excellence Center, King Chulalongkorn Memorial Hospital, Bangkok was between May and October 2019. Participants were interviewed and assessed for drug-related problems by clinical pharmacists.ResultsIn total, 54.5% (254) of the participants were aged 65-69 years and 77.0% (359) of the participants were women. Of the participants, 56.7% had three or more health conditions such as hyperlipidemia (62%), hypertension (46%), and cataract (18%). Fifty-five percent of the participants took five or more health products (polypharmacy) and 16% took ten or more products on a regular basis. Of the 2633 products used, 68% were prescription drugs and 32% were over-the-counter products. The prevalence of drug-related problems according to the criteria suggested by Cipolle-Strand-Morley (2012) was 63.3% (587 drug-related problems). Most of the problems came from: (a) non-adherence (28.6%); (b) needs for additional drug therapy (26.4%); and (c) adverse drug reactions (17.4%). Factors associated with drug-related problems were polypharmacy (odds ratio 2.50, 95% confidence interval 1.60-3.89) and multiple comorbidities [three or more conditions] (odds ratio 2.20, 95% confidence interval 1.41-3.43).ConclusionsThe prevalence of drug-related problems in urban-living older people at King Chulalongkorn Memorial Hospital in Bangkok was high. Polypharmacy and multiple comorbidities were significantly related to drug-related problems. To decrease the number of drug-related problems, pharmacists should collaborate with healthcare teams and suggest how to correctly reduce the number of health products being consumed by older people.