A nonlinear association between resting heart rate and ischemic stroke among community elderly hypertensive patients

Impact of resting heart rate on cardiovascular mortality according to serum albumin levels in a 24-year follow-up study on a general Japanese population: NIPPON DATA80

BackgroundElevated resting heart rate (RHR) is associated with an increased risk for cardiovascular disease (CVD) and all-cause mortality. However, the findings of cohort studies differed. Thus, the impact of RHR on CVD mortality might be different according to the background of the population. Therefore, we examined the relationship of RHR and CVD mortality according to serum ALB levels in a Japanese general population.MethodsIn total, 8363 individuals without a history of CVD were followed-up for 24.0 years. The participants were divided into four groups according to the quartiles of RHR (Q1-Q4), and they were further classified into the high and low ALB groups based on a median value of 44 g/L. We estimated the multivariable-adjusted hazard ratios (HRs) of CVD mortality in each RHR group based on ALB levels, and the interaction between RHR and ALB groups on CVD mortality was evaluated.ResultsWe found no significant association between RHR and CVD mortality. However, the Q4 of RHR was significantly associated with an increased risk for CVD mortality (HR: 1.27 [95% confidence interval, CI: 1.02-1.57]) in participants with a low ALB level. Meanwhile, the Q4 of RHR was significantly correlated with a decreased risk for CVD morality in those with a high ALB level (HR: 0.61 [95% CI: 0.47-0.79]) after adjusting for covariates. A significant interaction between RHR and ALB for CVD mortality was shown (p<0.001).ConclusionsThe impact of RHR on CVD mortality differed according to ALB levels in a general Japanese population.

The association of blood lipid parameters variability with ischemic stroke in hypertensive patients

BACKGROUND AND AIMS

The relationship between lipid variability and stroke among patients with hypertension were inconclusive. We aimed to investigate the association of lipid variability with ischemic stroke in hypertensive patients.

METHODS AND RESULTS

This retrospective cohort study included 4995 individuals with hypertension between 2013 and 2015, and recorded their status of ischemic stroke until the end of 2018. The variability in total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured using the standard deviation (SD), coefficient of variation (CV), variability independent of the mean (VIM) and average absolute difference between successive values (ASV). Multivariate Cox proportional hazards models with hazard ratios (HRs) and 95% confidence interval (CI) were performed. There were 110 cases of ischemic stroke during a median follow up of 4.2 years. The multivariable adjusted HRs and 95% CIs comparing the highest versus the lowest quartiles of SD of TC, LDL-C, HDL-C and TG were 4.429 (95% CI: 2.292, 8.560), 2.140 (95% CI: 1.264, 3.621), 1.368 (95% CI: 0.793, 2.359) and 1.421 (95% CI: 0.800, 2.525), respectively. High variability in TC and LDL-C were associated with a higher risk for ischemic stroke. Similarly, the results were consistent when calculating variability of TC and LDL-C using CV, ASV and VIM, and in various subgroup analyses.

CONCLUSION

Higher variability of TC and LDL-C associated with the risk of ischemic stroke among hypertensive patients. These findings suggest reducing variability of lipid parameters may decrease adverse outcomes.

Heart rate as a predictor of cardiovascular risk

Heart rate is a parameter that is very easy to measure and is widely used both in clinic and during daily life activities. Its value gained more relevance with the evidence, in prospective studies and meta-analysis, of association between elevated heart rate values and diseases and outcomes.The increased knowledge of physiological mechanisms of heart rate control and the pathophysiological mechanisms responsible for its dysfunction allows to identify the cut-off value of normalcy providing info for non-pharmacological and pharmacological treatments to reduce the cardiovascular risk both in general population and in pathophysiological conditions. This paper overviews the knowledges of the role of resting heart rate as predictor of cardiovascular risk.

Heart rate as cardiovascular risk factor

Heart rate is a parameter that is widely used by the general population as a marker of health. The availability of wearable electronic heart rate monitoring devices and use of specific apps are widely used both at rest and during daily life activities. Resting heart rate values gained more relevance with the evidence of association between elevated heart rate values at rest and diseases and adverse events. Also longitudinal studies demonstrated a clear association between increase in heart rate over time and cardiovascular and all-cause mortality. The increased knowledge of physiological mechanisms of heart rate control and the pathophysiological mechanisms responsible for its dysfunction allows identification of the cutoff value of normalcy. This information can be used to select non-pharmacological and pharmacological interventions to reduce the cardiovascular risk both in the general population and in patients with pathophysiological conditions. This review provides an overview of the current knowledge of resting heart rate as cardiovascular risk factor.