Methods: This study selected people aged 65 years and older from the first (2006) to fourth (2009) waves of the Korean Welfare Panel Study (KWPS). KWPS is a longitudinal survey of the social and individual status, social service, health condition and income activities of households and individuals residing in urban areas. The samples of KWPS are equal probability samples of households from 7 metropolitan cities and urban areas in 9 provinces and were designed to interview 7000 households and their members (aged 15 and over). The study sample included 1,681 elderly people who were either smokers or non-smokers at baseline, but all of whom smoked in the past. Participants completed an annual questionnaire. Depressive symptoms were measured by an 11-item version of the CES-D (CESD11), a self-report of the frequency of depressive symptoms over the past week (0= rarely to 3 = most of the time). CESD11 scores could range from 0 to 33, higher scores representing higher depressive symptomatology. Smoking was operationalized as the number of packs of cigarettes smoked per day (0 to 4).
Results: Average depressive symptomatology at baseline (intercept) was 16.39 and the average linear rate of change (slope) in depressive symptoms was 1.17. Average number of packs smoked per day at baseline (intercept) was 0.56 and the average linear rate of change (slope) was 0.01. Depressive symptomatology and smoking intercepts were weakly but significantly correlated (Estimate = .06). Also, the slopes of depressive symptomatology and smoking behavior were significantly and positively correlated (Estimate = .14). Correlations were negative between the smoking intercept and slope (Estimate = -.26) and the depressive symptoms intercept and slope (Estimate = -.43).
Conclusions and Implications: Based on latent growth modeling, this study demonstrated that depressive symptoms and smoking behaviors are significantly related both at baseline and over time in South Korean elders. These results argue for assessment of possible co-occurrence of depressive symptoms and smoking, and for interventions that target both problems, when serving South Korean elders. When providing a smoking cessation program to help elderly smokers, social workers should consider the depressive symptoms of the elderly people before they participate in the smoking cessation program. For elders with high depressive symptoms, social workers should consider providing interventions to help these elders engage in health promotion behaviors such as smoking cessation or prevention. Further research is needed to unravel the causal relationships between smoking and depressive symptoms.
