School of Public Health, University of Haifa, Israel (G.W.).
Department of Biostatistics, Boston University School of Public Health, MA (K.D.-P., A.S.B.).
Stroke. 2021 Jun;52(6):2068-2076. doi: 10.1161/STROKEAHA.120.030601. Epub 2021 Apr 20.
The autonomic nervous system has been implicated in stroke and dementia pathophysiology. High resting heart rate and low heart rate variability indicate the effect of autonomic imbalance on the heart. We examined the associations of resting heart rate and heart rate variability with incident stroke and dementia in a community-based cohort of middle- and old-aged adults.
The study sample included 1581 participants aged >60 years and 3271 participants aged >45 years evaluated for incident dementia and stroke, respectively, who participated in the Framingham Offspring cohort third (1983–1987) examination and had follow-up for neurology events after the seventh (1998–2001) examination. Heart rate variability was assessed through the standard deviation (SD) of normal-to-normal RR intervals and the root mean square of successive differences between normal heartbeats from 2-hour Holter monitor. Participants were followed-up for stroke and dementia incidence from exam 7 to a maximum of 10 years. Cox regression models were used to assess the link of resting heart rate and heart rate variability with stroke and dementia risk while adjusting for potential confounders, and interactions with age and sex were assessed.
Of the dementia (mean age, 55±6 years, 46% men) and stroke (mean age, 48±9 years, 46% men) samples, 133 and 127 developed dementia and stroke, respectively, during the follow-up. Overall, autonomic imbalance was not associated with dementia risk. However, age modified the associations such that SD of normal-to-normal intervals and root mean square of successive differences were associated with dementia risk in older people (hazard ratio [HR] [95% CI] per 1SD, 0.61 [0.38–0.99] and HR [95% CI] per 1SD, 0.34 [0.15–0.74], respectively). High resting heart rate was associated with increased stroke risk (HR [95% CI] per 10 bpm, 1.18 [1.01–1.39]), and high SD of normal-to-normal intervals was associated with lower stroke risk in men (HR [95% CI] per 1SD, 0.46 [0.26–0.79]) but not women (HR [95% CI] per 1SD, 1.25 [0.88–1.79]; P for interaction=0.003).
Some measures of cardiac autonomic imbalance may precede dementia and stroke occurrence, particularly in older ages and men, respectively.
自主神经系统与中风和痴呆的病理生理学有关。静息心率高和心率变异性低表明自主平衡对心脏的影响。我们在一项基于社区的中老年人群队列中，研究了静息心率和心率变异性与中风和痴呆发病的相关性。
研究样本包括年龄>60 岁的 1581 名参与者和年龄>45 岁的 3271 名参与者，分别评估了他们发生痴呆和中风的情况。他们参加了弗雷明汉后代队列的第三次（1983-1987 年）检查，并在第七次（1998-2001 年）检查后进行了神经系统事件的后续随访。心率变异性通过正常到正常 RR 间期的标准差（SD）和 2 小时动态心电图监测中正常心跳之间连续差异的均方根来评估。参与者从检查 7 开始进行中风和痴呆的发病风险随访，最长随访时间为 10 年。Cox 回归模型用于评估静息心率和心率变异性与中风和痴呆风险之间的联系，同时调整了潜在的混杂因素，并评估了年龄和性别之间的相互作用。
在痴呆（平均年龄 55±6 岁，46%为男性）和中风（平均年龄 48±9 岁，46%为男性）样本中，分别有 133 人和 127 人在随访期间发生了痴呆和中风。总的来说，自主神经失衡与痴呆风险无关。然而，年龄改变了这种关联，使正常到正常间期的 SD 和连续差异的均方根与老年人的痴呆风险相关（每增加 1SD 的风险比[HR] [95%CI]，0.61 [0.38-0.99]和 HR [95%CI]，0.34 [0.15-0.74]）。高静息心率与中风风险增加相关（每增加 10 次/分钟的 HR [95%CI]，1.18 [1.01-1.39]），而正常到正常间期的 SD 较高与男性中风风险降低相关（每增加 1SD 的 HR [95%CI]，0.46 [0.26-0.79]），但与女性无关（每增加 1SD 的 HR [95%CI]，1.25 [0.88-1.79]；P 交互=0.003）。
一些心脏自主神经失衡的指标可能先于痴呆和中风的发生，特别是在老年人和男性中。
