Albumin, apolipoprotein E-epsilon4 and cognitive decline in community-dwelling Chinese older adults

To examine the association between serum albumin and cognitive impairment and decline in community-living older adults.

Population-based cohort study, followed up to 2 years; serum albumin, apolipoprotein E (APOE)-epsilon4, and cognitive impairment measured at baseline and cognitive decline (> or =2-point drop in Mini-Mental State Examination (MMSE) score). Odds ratios were controlled for age, sex, education, medical comorbidity, hypertension, diabetes mellitus, cardiac disease, stroke, smoking, alcohol drinking, depression, APOE-epsilon4, nutritional status, body mass index, anemia, glomerular filtration rate, and baseline MMSE.

Local area whole population.

One thousand six hundred sixty-four Chinese older adults aged 55 and older.

The mean age of the cohort was 66.0+/-7.3, 65% were women, mean serum albumin was 42.3+/-3.1 g/L, and mean MMSE score was 27.2+/-3.2. Lower albumin tertile was associated with greater risk of cognitive impairment in cross-sectional analysis (low, odds ratio (OR)=2.30, 95% confidence interval (CI)=1.31-4.03); medium, OR=1.59, 95% CI=0.88-2.88) versus high (P for trend=.002); and with cognitive decline in longitudinal analyses: low, OR=1.73, 95% CI=1.18-2.55; medium, OR=1.32, 95% CI=0.89-1.95, vs high (P for trend=.004). In cognitively unimpaired respondents at baseline (MMSE> or =24), similar associations with cognitive decline were observed (P for trends <.002). APOE-epsilon4 appeared to modify the association, due mainly to low rates of cognitive decline in subjects with the APOE-epsilon4 allele and high albumin.

Low albumin was an independent risk marker for cognitive decline in community-living older adults.