Background: South Korea faces a rapidly aging population and a steady increase in older adults living alone, who represent a health-vulnerable population. Due to weaker social support and a high prevalence of chronic conditions, these individuals freq...
Background: South Korea faces a rapidly aging population and a steady increase in older adults living alone, who represent a health-vulnerable population. Due to weaker social support and a high prevalence of chronic conditions, these individuals frequently rely on over-the-counter(OTC) drugs for self-medication. While OTC drugs are generally safe, their unsupervised use poses risks such as misdiagnosis and adverse drug events (ADEs). Given the heightened vulnerability of older adults to ADEs, particularly with polypharmacy, appropriate medication safety management is critical. This study aims to analyze how demographic, socioeconomic, and health-related factors influence both the long-term use and expenditure of OTC drugs among older adults living alone.
Method: This study utilized data from the Korea Health Panel Survey (KHP) spanning 2011 to 2018. The final sample included 5,828 individuals aged 65 years and older living alone. A modified Two-Part Model framework was employed for analysis. Part 1 involved a logistic regression to identify determinants of OTC drug use for three months or longer. Part 2 used a multiple linear regression among long-term users to analyze factors affecting monthly OTC expenditure. Independent variables were structured based on the Andersen's Behavioral Model, categorized as predisposing, enabling, and need factors.
Result: A total of 13.7%(n=799) of older adults living alone reported long-term OTC use. In the logistic regression, the likelihood of long-term use was significantly higher among women, those aged 75–84 (vs. 65–74), individuals with at least a middle school education, and those not engaged in economic activity. Crucially, long-term use was also associated with disability, poor self-rated health, and a higher number of outpatient visits. In the multiple linear regression, the second income quintile demonstrated the highest average spending. Consistent with Part 1, expenditure increased significantly with the number of chronic diseases, the presence of disability, and poorer self-rated health.
Conclusion: First, the long-term use of OTC medications and the level of related expenditures among older adults living alone were not explained by identical factors, suggesting that greater health needs do not necessarily translate into higher spending. Second, frequent outpatient visits were associated with an increased likelihood of long-term OTC use, indicating that such medications function as complementary self-care tools rather than substitutes for formal healthcare among this population. Third, need factors such as poor self-rated health and disability were significantly associated with both the probability of long-term use and the level of expenditures, implying that older adults with greater health vulnerabilities tend to rely more heavily on self-medication. These findings help to elucidate the structural conditions under which older adults with poor health status engage in prolonged OTC medication use. Considering the safety concerns raised in prior studies regarding long-term OTC consumption, policy efforts should incorporate medication counseling, information provision, and monitoring strategies to promote safe and appropriate medication use in this vulnerable population.