From the University Health Network and Sinai Health System Division of Cardiology, Department of Medicine, University of Toronto and the Toronto General Research Institute, University Health Network, Toronto, ON, Canada (D.A.K., M.B.B., G.T., C.F.N., D.S.K., P.J.M., J.S.F.).
School of Kinesiology, University of Western Ontario, London, ON, Canada (M.B.B., J.K.S.).
Hypertension. 2020 Sep;76(3):997-1005. doi: 10.1161/HYPERTENSIONAHA.120.15208. Epub 2020 Aug 12.
As with blood pressure, age-related changes in muscle sympathetic nerve activity (MSNA) may differ nonlinearly between sexes. Data acquired from 398 male (age: 39±17; range: 18-78 years [mean±SD]) and 260 female (age: 37±18; range: 18-81 years) normotensive healthy nonmedicated volunteers were analyzed using linear regression models with resting MSNA burst frequency as the outcome and the predictors sex, age, MSNA, blood pressure, and body mass index modelled with natural cubic splines. Age and body mass index contributed 41% and 11%, respectively, of MSNA variance in females and 23% and 1% in males. Overall, changes in MSNA with age were sigmoidal. At age 20, mean MSNA of males and females were similar, then diverged significantly, reaching in women a nadir at age 30. After 30, MSNA increased nonlinearly in both sexes. Both MSNA discharge and blood pressure were lower in females until age 50 (17±9 versus 25±10 bursts·min; <1×10; 106±11/66±8 versus 116±7/68±9 mm Hg; <0.01) but converged thereafter (38±11 versus 35±12 bursts·min; =0.17; 119±15/71±13 versus 120±13/72±9 mm Hg; >0.56). Compared with age 30, MSNA burst frequency at age 70 was 57% higher in males but 3-fold greater in females; corresponding increases in systolic blood pressure were 1 (95% CI, -4 to 5) and 12 (95% CI, 6-16) mm Hg. Except for concordance in females beyond age 40, there was no systematic change with age in any resting MSNA-blood pressure relationship. In normotensive adults, MSNA increases after age 30, with ascendance steeper in women.
与血压一样，肌肉交感神经活动（MSNA）的年龄相关性变化在性别之间可能是非线性的。对 398 名男性（年龄：39±17；范围：18-78 岁[均值±标准差]）和 260 名女性（年龄：37±18；范围：18-81 岁）的健康非药物治疗的正常血压非吸烟者进行数据分析，采用线性回归模型，以静息 MSNA 爆发频率作为因变量，性别、年龄、MSNA、血压和体重指数作为预测变量，用自然三次样条建模。年龄和体重指数分别占女性 MSNA 方差的 41%和 11%，占男性的 23%和 1%。总体而言，MSNA 随年龄的变化呈类正弦曲线。在 20 岁时，男性和女性的平均 MSNA 相似，然后显著分离，在女性中 30 岁时达到最低点。30 岁以后，男女的 MSNA 均呈非线性增加。直到 50 岁，女性的 MSNA 放电和血压均较低（17±9 与 25±10 爆发·min；<1×10；106±11/66±8 与 116±7/68±9 mmHg；<0.01），但此后趋于一致（38±11 与 35±12 爆发·min；=0.17；119±15/71±13 与 120±13/72±9 mmHg；>0.56）。与 30 岁相比，男性 70 岁时 MSNA 爆发频率增加了 57%，而女性则增加了 3 倍；相应的收缩压增加了 1（95%CI，-4 至 5）和 12（95%CI，6-16）mmHg。除了 40 岁以上女性的一致性外，静息 MSNA-血压关系没有随着年龄的变化而系统地改变。在正常血压成年人中，MSNA 在 30 岁后增加，女性的上升幅度更大。
