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. Hypertension Research ( 2009) 32, 554-558; doi: 10.1038/hr.2009.72; published online 29 May 2009