Polypharmacy among nonagenarians/centenarians in rural China

BACKGROUND: Little is known about the prevalence and relevant factors of polypharmacy in nonagenarian and centenarians. AIM: The aim of this study is to examine the prevalence and associated factors of polypharmacy in a sample of nonagenarians and centenarians living in a rural area of China. METHODS: The data were from the 'Project of Longevity and Aging in Dujiangyan' study. Medication use and relevant covariates were obtained by face-to-face interviews. Minor polypharmacy was defined as the concomitant use of two to four medications, whereas major polypharmacy referred to the concomitant use of five or more medications. RESULTS: We included 859 participants with mean age of 93.7 ± 3.3 years. The number of chronic diseases was 1.4 ± 1.2 per subject, whereas the number of drugs was 0.8 ± 1.4 per subject. The prevalence of minor polypharmacy and major polypharmacy was 16.5% and 3.7% respectively. Illiteracy (odds ratio (OR) 2.93, 95% confidence interval (CI) 1.52 to 5.66), cognitive impairment (OR 3.15, 95% CI 1.44 to 6.88), hypertension (OR 2.88, 95% CI 1.46 to 5.67), respiratory disease (OR 2.22, 95% CI 1.08 to 4.58), osteoarthritis (OR 1.24, 95% CI 1.01 to 1.51), and cancer (OR 10.70, 95% CI 1.90 to 126.80) were positively associated with minor polypharmacy. Illiteracy (OR 4.24, 95% CI 1.53 to 11.81), hypertension (OR 3.40, 95% CI 1.22 to 9.49) and cancer (OR 3.40, 95% CI 1.14 to 10.12) were also positively associated with major polypharmacy. CONCLUSIONS: Although most subjects suffer from some chronic diseases, minor polypharmacy and major polypharmacy are not common among nonagenarians/centenarians in rural China.