Associations of changes in late-life blood pressure with cognitive impairment among older population in China.

BACKGROUND: The cognitive impact of changes in late-life blood pressure is less clear. We aimed to investigate the association between late-life blood pressure changing pattern and risk of cognitive impairment. METHODS: Using data from the community-based Chinese Longitudinal Healthy Longevity Survey, change in systolic (SBP) or diastolic (DBP) blood pressure was calculated as the difference between follow-up and baseline, cognitive impairment was defined based on both the Mini-Mental State Examination and education level. The generalized additive model with penalized spline and multivariate logistic regression model were used, respectively, to examine the associations between continuous and categorized blood pressure changes with cognitive impairment at the follow-up wave. RESULTS: A total of 8493 Chinese elderly without cognitive impairment were included, with mean (standard deviation) age 80.6 (10.7) years. U-shaped associations between late-life blood pressure changes and risk of cognitive impairment were found, with only stable optimal blood pressure related to the lowest risk. For participants with baseline SBP around 130-150 mmHg, the adjusted odds ratio was 1.48 (1.13-1.93) for increasing follow-up SBP (> 150 mmHg), 1.28 (1.02-1.61) for decreasing follow-up SBP (< 130 mmHg), compared to stable follow-up SBP (130-150 mmHg). For participants with relative lower baseline DBP (< 80 mmHg), increasing their DBP to 80-90 mmHg during follow-up was associated with lower cognitive impairment risk (0.73 (0.58-0.93)), compared to steady low follow-up DBP (< 80 mmHg). Sex-specific analysis suggested that men were more vulnerable in term of SBP change. CONCLUSIONS: Adhering to a stable optimal level of blood pressure in late-life is related to lower risk of cognitive impairment in Chinese elderly.

Changes in late-life systolic blood pressure and all-cause mortality among oldest-old people in China: the chinese longitudinal healthy longevity survey.

BACKGROUND: Blood pressure targets for oldest-old people have been long debated due to the concern that more stringent targets are associated with increased mortality. We aimed to investigate the association between changes of late-life systolic blood pressure (SBP), mean SBP and SBP variability (SBPV), and all-cause mortality in oldest-old. METHODS: Based on the community-based Chinese Longitudinal Healthy Longevity Survey with follow-up conducted in the 3-year interval, we assembled a retrospective cohort of 6639 participants ≥ 80 years with available blood pressure measurements at baseline and second wave. The primary exposures were mean SBP and SBPV (defined as the annual difference in SBP divided by mean SBP) measured between baseline and second wave. The primary outcome was all-cause mortality assessed from the second wave. RESULTS: During 21443.1 person-years of follow-up, 4622 death was recorded. U-shaped associations of mortality with mean SBP and SBPV were identified; the value of 137 mmHg and 4.0 %/year conferred the minimum mortality risk, respectively. The associations of a larger SBPV with an increased mortality risk were observed for both rises and large falls in SBP. The hazard ratio was 1.11 (comparing lowest versus middle quintile; 95 % CI: 1.01, 1.22) with large falls in SBPV and 1.08 (comparing highest versus middle quintile; 95 % CI: 0.98, 1.18) with large rises in SBPV. CONCLUSIONS: U-shaped associations between late-life SBP and SBPV and all-cause mortality were found. Our study suggests that a stable SBP level in the middle range is related to lower mortality risk in the oldest-old.

Urinary trichloroacetic acid and high blood pressure: A cross-sectional study of general adults in Shijiazhuang, China.

Exposure to trichloroacetic acid (TCAA) and its parent chemicals potentially linked to cardiovascular disease. However, the association between TCAA and blood pressure (BP) has not been studied to date. The purpose of this study was to examine the potential association between urinary TCAA levels and BP in a Chinese population. We measured BP parameters (including systolic BP, diastolic BP and pulse pressure) and TCAA concentrations in the urine of 569 adults from a primary health care clinic in Shijiazhuang, China. Logistic and linear regressions were used to investigate the relationships between the urinary TCAA levels and BP parameters. To evaluate the robustness of the results, we conducted sensitivity analyses by re-analysing data after excluding urine samples with extreme specific creatinine values. We found that urine TCAA levels were positively associated with systolic BP and pulse pressure based on trend tests after adjusting for potential confounders (both p for trend < 0.05). Finally, only the association of TCAA with systolic BP remained significant in the sensitivity analyses (p < 0.05). Our results suggested that TCAA exposure was associated with increased BP in adults. Because urinary TCAA has been proposed as a valid biomarker of disinfection by-product (DBP) ingestion through disinfected drinking water, our results further suggest that exposure to drinking water DBPs may contribute to high BP in humans. Additional research is needed to confirm these findings and to evaluate opportunities for intervention.