Table 1.
Sample characteristics stratified by sex.
| Women (n = 90) | Men (n = 88) | P value | |
|---|---|---|---|
| Mean (SD) or N (%) | |||
| SDNN (ms2) | 103 (25.6) | 110 (30.0) | 0.096 |
| RMSSD (ms2) | 30 (14.6) | 30 (16.7) | 0.815 |
| Age years | 64 (14.3) | 66 (11.8) | 0.198 |
| Systolic blood pressure (mm Hg) | 119 (16.6) | 123 (14.2) | 0.107 |
| Body mass index (kg/m2) | 27 (4.9) | 27 (3.9) | 0.226 |
| Waist circumference (cm) | 88 (14.0) | 98 (12.9) | <0.001 |
| Fasting glucose (mg/dL) | 93 (13.1) | 98 (17.7) | 0.026 |
| OGTT 2-hour glucose (mg/dL) | 118 (43.5) | 133 (54.7) | 0.067 |
| Black race† | 26 (29%) | 24 (26%) | 0.681 |
| Antihypertensive use | 40 (44%) | 46 (52%) | 0.371 |
| Beta blocker use | 16 (18%) | 21 (24%) | 0.317 |
| Hypertension | 50 (56%) | 56 (63%) | 0.353 |
†Self-reported race/ethnicity (N) included: Caucasian (118), black or African American (50), Asian or Pacific islanders (4), American Indian or native Alaskan (1), Hispanic (2), Chinese (3), and other or unknown (1).
ms: milliseconds; OGTT: oral glucose tolerance test; RMSSD: root mean square of successive differences in normal-to-normal intervals; SDNN: standard deviation of normal-to-normal intervals.