Associations of Pulmonary Function with Dementia and Depression in an Older Korean Population

OBJECTIVE: Previous studies reported an association between pulmonary function and cognitive function. However, not much has been investigated in this regard concerning dementia in a community population, taking depression into account. We aimed to examine the associations of pulmonary function with dementia and depression in a community-dwelling elderly population. METHODS: A total of 1,038 participants were evaluated for dementia and depression using the Korean version of the Geriatric Mental State Schedule B3 (GMS B3-K), the Community Screening Interview for Dementia-Korean version (CSID-K) and a modified 10-item Word List Learning from the Consortium to Establish a Registry of Alzheimer's Disease (CERAD). Pulmonary function was measured as forced expiratory volume in 1 s (FEV(1)) from a forced expiratory maneuver. RESULTS: Prevalence rates of dementia and depression were 11.0% and 10.4%, respectively. Individuals who were diagnosed with dementia manifested a lower mean FEV(1), as compared to those without dementia after adjusting for potential confounders, including disability and depression [OR=1.34 (1.05-1.72)]. Following gender-stratified analysis, the association was only statistically significant in women [OR=1.40 (1.04-1.89)]. The association between depression and mean FEV(1) was less significant compared to dementia [OR=1.32 (1.10-1.58)]. However, the association was no longer significant after adjusting for age and years of education. No association was significant in the gender-stratified analysis. CONCLUSION: Decreased pulmonary function was associated with dementia status only in an older female Korean population. Pulmonary function and depression were not significantly associated in either gender.