Prevalence and Correlates of Polypharmacy, and Drug Utilization Pattern in a Semi-urban Population: Results from the Pars Cohort Study.

BACKGROUND: Although polypharmacy is considered a major predictor of irrational use of drugs, little is known about polypharmacy in developing regions. We aimed to indicate the prevalence and correlates of polypharmacy and to determine the medication profile at the population level in southern Iran. METHODS: In this cross-sectional study, we analyzed data from participants of the Pars Cohort Study (PCS) (aged above 40 years, N=9269). Polypharmacy was defined as using five or more medications concurrently. A Poisson multivariable model was applied to estimate the adjusted prevalence ratios (APRs) of various risk factors. The Anatomical Therapeutic Chemical (ATC) classification system was used for classifying medications. RESULTS: Prevalence of polypharmacy was 10.4%, (95% CI: 9.75; 11.08) and it was higher among females (15.0%), older adults (age≥65 years) (16.0%), and individuals with more than two chronic conditions (31%). Being female, educated, married, and not having a low socio-economic class were independently associated with a higher likelihood of polypharmacy. The most prevalent medications among female participants were sex hormones and modulators of the genital system (58.4%), drugs for acid-related disorders (14.6%), and anti-anemic preparations (13.6%,). On the other hand, males were using acid-related disorders (14.6%), anti-inflammatory and anti-rheumatic products (7.8%), and beta-blocking agents (6.3%). CONCLUSION: The prevalence of polypharmacy in our sample was relatively low, especially among males. Cardiovascular drugs, acid suppressants, hormonal contraceptives, and anti-anemic preparations are drug classes with the highest contribution to polypharmacy.

Population-based prevalence of polypharmacy and patterns of medication use in southwestern Iran: A cross-sectional study.

BACKGROUND: Pharmaceutical medications are considered an important component of healthcare delivery and there is a need for its rational use; although there have been major improvements in the pharmaceutical sector in the recent past, inappropriate medication use is considered a major threat to patients' health. Therefore, the pattern of medication use should be monitored routinely. The aim of this study was to investigate the population-based prevalence of polypharmacy and the patterns of medication use in southwestern Iran. We also investigated correlates between polypharmacy and patterns of medication use. METHODS: Data from the Khuzestan Comprehensive Health Study (KCHS) which consists information of 30 506 with age range to 20 to 65 years were used. Crude and age-standardized prevalence of polypharmacy and their 95% confidence intervals were estimated for different subpopulations. Multivariable Poisson regression modeling was applied, and adjusted prevalence ratios and their 95% confidence intervals were estimated. The Anatomical Therapeutic Chemical classification system (first and second levels) was used for drug classification in different groups based on age, gender, and socioeconomic status. RESULTS: Out of 30 506 adults, 93.3% were not on any medications, and age- and gender-standardized prevalence of polypharmacy was 0.24%. The lowest estimated prevalence was among Arab participants (0.13%). The prevalence of polypharmacy was 1.57% among elderly people, and 4.78% among patients with heart diseases. Socioeconomic status was not associated with polypharmacy (prevalence ratio: 0.95; p = 0.573) but was significantly associated with patterns of medications use for alimentary tract and metabolism and nervous system diseases. The most common drug classes were cardiovascular system (3.93%), alimentary tract and metabolism (2.79%), nervous system (1.01%), systemic hormonal preparations (0.69%), and blood and blood-forming organs (0.38%). CONCLUSIONS: The prevalence of polypharmacy is very low in Khuzestan province, especially in the Arab population. Future research is needed to investigate the causes of medication underuse in this population.