Systolic Blood Pressure and Mortality in Community-Dwelling Older Adults: The Role of Frailty.

OBJECTIVES: To investigate whether frailty modifies the association of systolic blood pressure (SBP) with cardiovascular mortality and all-cause mortality in community-dwelling older adults. DESIGN: A prospective cohort study. SETTING: A population-based study of nationally representative older Chinese adults in a community setting. PARTICIPANTS: This study included participants aged 65 years or older from the Chinese Longitudinal Healthy Longevity Survey 2002-2014 and followed up to 2018. MEASUREMENTS: Participants were divided into two groups according to a frailty index based on the accumulation of a 44-items deficits model. The association between SBP and mortality was analyzed using multivariable-adjusted Cox proportional hazards models. RESULTS: Among 18,503 participants included, the mean age was 87.2 years and the overall median follow-up time was 42.7 months. We identified 7808 (42.2%) frail participants (mean frailty index=0.33), in which 7533 (96.5%) died during the follow-up. Effect modification by frailty was detected (P for interaction=0.032). Among frail participants, a U-shaped association was found with hazard ratios of 1.16 (95% CI, 1.02-1.32) for SBP < 100 mmHg, and 1.11 (95% CI, 1.00-1.24) for SBP ≥ 150 mmHg compared with SBP 120-130 mmHg. For non-frail older adults, a tendency toward higher risk among those with SBP ≥ 130 mmHg was observed. The analyses towards cardiovascular mortality showed similar results. CONCLUSION: Our results suggest the presence of effect modification by frailty indicating a possible negative effect for elevated SBP in non-frail older adults and a U-shaped relationship of SBP in frail older adults with respect to mortality even after adjusting for diastolic blood pressure.

Circulating miR-92a expression level in patients with essential hypertension: a potential marker of atherosclerosis.

MicroRNAs (miRs) are key posttranscriptional regulators of gene expression in all eukaryotic cells and have a vital role in the evolution of hypertension and cardiovascular remodelling and, therefore, have emerged as potential biomarkers for cardiovascular disease. We assessed 240 participants, including 60 healthy volunteers with normal carotid intima-media thickness (nCIMT), 60 healthy volunteers with increased CIMT (iCIMT), 60 hypertensive patients with nCIMT and 60 hypertensive patients with iCIMT. All patients underwent measurements of CIMT, carotid-femoral pulse wave velocity (cfPWV) and ambulatory blood pressure (BP) monitoring. Plasma miR-92a expression was quantified by real-time reverse transcription PCR. Correlations between miR-92a expression and BP parameters, CIMT and cfPWV were assessed using the Spearman correlation coefficient. We observed the lowest miR-92a expression (24.59±1.30 vs 27.76±2.13 vs 29.29±1.89 vs 33.76±2.08; P<0.001) in healthy controls with nCIMT, followed by healthy controls with iCIMT, then hypertensive patients with nCIMT and the highest expression in hypertensive patients with iCIMT. Additionally, MiR-92a levels showed a significant positive correlation with 24-h mean systolic BP (r=0.807, P<0.001), 24-h mean diastolic BP (r=0.649, P<0.001), 24-h mean pulse pressure (PP) (r=0.697, P<0.001), 24-h daytime PP (r=0.654, P<0.001), 24-h nighttime PP (r=0.573, P<0.001), CIMT (r=0.571, P<0.001) and cfPWV (r=0.601, P<0.001). Our data present significant evidence that circulating miR-92a represents a potential noninvasive atherosclerosis marker in essential hypertensive patients.