Cognitive impairment and hypertension among Chinese nonagenarians and centenarians

In this study, we explore the association between hypertension and cognitive impairment in the very elderly, using a sample ranging in age from 90 to 108 years. This work was conducted as a cross-sectional study. Our population included 782 unrelated Chinese nonagenarians and centenarians (67.5% women, mean age 93.62 years). The mean cognitive function score for the sample was 14.95 (s.d.: 5.99, range: 0-28). There were no significant differences between individuals with and without hypertension with regard to cognitive function scores (14.95+/-6.01 vs. 14.95+/-5.82, P=0.997) or cognitive impairment prevalence (59.52 vs. 59.42, P=0.976). There were also no significant differences in the prevalence of hypertension (56.99 vs. 57.10, P=0.976) or in the levels of arterial blood pressure (including systolic blood pressure (SBP) and diastolic blood pressure (DBP)) (139.86+/-22.69 vs. 140.28+/-23.51, P=0.799 and 73.05+/-12.07 vs. 72.11+/-12.06, P=0.678, for SBP and DBP, respectively) between individuals with and without cognitive impairment. Multiple logistic regression showed that cognitive impairment and hypertension were not risk factors for each other (odds ratio (OR) of cognitive impairment as a function of increased hypertension: 0.938 (0.655, 1.341); OR of hypertension as a function of increased cognitive impairment: 0.920 (0.643, 1.317)). In summary, we found that cognitive impairment was not directly correlated with hypertension among Chinese nonagenarians and centenarians.