Table 2.

Resting hemodynamic variables in YF, YM, and PMF

	YF	YM	PMF	Test Statistic	P Value
MSNA, bursts/100 HB	53 [13]*	51 [11]*	79 [17]	χ2(2) = 20.131	<0.0005
MSNA, bursts/min	33 [10]*	29 [6]*	52 [13]	χ2(2) = 21.090	<0.0005
MSNA, total area/s, %	8.6 [3.4]*	8.4 [1.6]*	10.9 [3.3]	χ2(2) = 14.922	0.0006
Heart rate, beats/min	62 ± 10	58 ± 9	64 ± 7	F(2, 34) = 1.458	0.247
SBP, mmHg	136 [17]	125 [8]*	146 [21]	χ2(2) = 10.866	0.004
DBP, mmHg	78 [13]	69 [9]	72 [13]	χ2(2) = 1.945	0.378
PP, mmHg	59 ± 7†	52 ± 5*	71 ± 16	F(2,21.1) = 10.545	0.001
MAP, mmHg	98 [12]	88 [8]	97 [14]	χ2(2) = 5.474	0.065
sBRS occurrence, % bursts/mmHg	−5.3 [1.6]	−7.1 [4.3]*	−3.4 [3.7]	χ2(2) = 8.423	0.015
sBRS area, %/mmHg	−0.51 ± 0.29	−0.62 ± 0.28	−0.56 ± 0.25	F(2, 34) = 0.456	0.638
Breathing rate, breaths/min	14 [2]	13 [6]	13 [5]	χ2(2) = 0.401	0.818
Normalized respiratory trace amplitude, %	46 ± 15	55 ± 17	50 ± 19	F(2, 34) = 0.829	0.445
Respiratory cycle duration, s	4.1 [0.6]	4.5 [2.1]	4.6 [1.7]	χ2(2) = 0.707	0.702

Values are represented as means ± SD or medians [interquartile ranges]. YF, premenopausal females; HB, heartbeats; sBRS, sympathetic baroreflex sensitivity; χ, Kruskal–Wallis test statistic; F, ANOVA test statistic. Group differences tested by univariate ANOVA or Kruskal–Wallis test. Welch’s correction was applied to pulse pressure (PP) data.

^*P < 0.05 vs. postmenopausal females (PMF); †P < 0.05 vs. younger males (YM) (exact P values in text). Multiple comparisons for muscle sympathetic nerve activity (MSNA), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), breathing rate compared mean ranks.