Change of Cognitive Function and Associated Factors among the Rural Elderly: A 5-Year Follow-up Study

Abstract

This prospective population-based cohort study was conducted to evaluate the risk factors of cognitive impairment and the degree of cognitive function change through a 5-year follow-up. The baseline and follow-up surveys were conducted in 1998 and 2003, respectively. Among 176 subjects who had normal cognitive function in the baseline study, 136 were followed up for 5 years. The cognitive function was investigated using the Korean version of the Mini-Mental State Examination (MMSE-K). The collected data were analyzed using SPSS and Stata. Of the 136 subjects analyzed, 25 (18.4%) were cognitively impaired. Old age and low social support in the baseline survey were risk factors for cognitive impairment after 5 years. In the generalized estimating equation for 128 subjects except severe cognitive impairment about the contributing factors of cognitive function change, the interval of 5 years decreased MMSE-K score by 1.02 and the cognitive function was adversely affected with increasing age, decreasing education and decreasing social support. Although the study population was small, it was considered that the study results can be used to develop a community-based prevention system for cognitive impairment.