Table 1.
Baseline characteristics of the study population before propensity score matching
| Characteristic | Total | ED | P | |
|---|---|---|---|---|
|
| ||||
| No | Yes | |||
| Patients, n (%) | 3184 (100.0) | 2321 (72.9) | 863 (27.1) | |
| Age (year), mean (s.e.) | 45.4 (0.4) | 41.6 (0.4) | 61.5 (0.6) | <0.0001 |
| Race, n (%) | 0.01 | |||
| Caucasian | 1750 (55.0) | 1227 (73.4) | 523 (79.7) | |
| African American | 569 (17.9) | 450 (10.4) | 119 (7.4) | |
| Others | 865 (27.2) | 644 (16.2) | 221 (12.9) | |
| Marital status, n (%) | <0.0001 | |||
| Married/living with a partner | 2253 (70.8) | 1598 (68.3) | 655 (78.5) | |
| Single/divorced/widowed | 931 (29.2) | 723 (31.7) | 208 (21.5) | |
| Education level, n (%) | <0.0001 | |||
| Less than high school | 849 (26.7) | 517 (13.2) | 332 (27.9) | |
| High school or equivalent | 786 (24.7) | 605 (26.2) | 181 (24.5) | |
| College or above | 1549 (48.7) | 1199 (60.7) | 350 (47.6) | |
| BMI (kg m−2), n (%) | <0.001 | |||
| <30.00 | 2278 (71.6) | 1691 (72.3) | 587 (62.7) | |
| ≥30.00 | 906 (28.5) | 630 (27.7) | 276 (37.3) | |
| PIR, n (%) | <0.001 | |||
| ≤1.30 | 732 (23.0) | 515 (16.6) | 217 (16.7) | |
| 1.31–3.50 | 1258 (39.5) | 869 (32.6) | 389 (43.7) | |
| >3.50 | 1194 (37.5) | 937 (50.8) | 257 (39.6) | |
| Smoking status, n (%) | <0.0001 | |||
| Never | 1286 (40.4) | 1027 (45.3) | 259 (29.8) | |
| Former | 1049 (33.0) | 616 (26.1) | 433 (48.1) | |
| Now | 849 (26.7) | 678 (28.6) | 171 (22.2) | |
| Drinking status, n (%) | <0.0001 | |||
| Never | 211 (6.6) | 152 (7.5) | 59 (7.2) | |
| Former | 648 (20.4) | 366 (13.3) | 282 (30.2) | |
| Now | 2325 (73.0) | 1803 (79.2) | 522 (62.7) | |
| Recreational activity, n (%) | <0.0001 | |||
| Vigorous | 1097 (34.5) | 949 (45.3) | 148 (18.2) | |
| Moderate | 895 (28.1) | 600 (26.9) | 295 (39.6) | |
| Inactivity | 1192 (37.4) | 772 (27.7) | 420 (42.2) | |
| Hypercholesterolemia, n (%) | <0.0001 | |||
| No | 1998 (62.8) | 1547 (66.1) | 451 (47.4) | |
| Yes | 1186 (37.3) | 774 (33.9) | 412 (52.6) | |
| CVD, n (%) | <0.0001 | |||
| No | 2761 (86.7) | 2161 (94.6) | 600 (71.2) | |
| Yes | 423 (13.3) | 160 (5.5) | 263 (28.8) | |
| Hypertension, n (%) | <0.0001 | |||
| No | 1909 (60.0) | 1588 (69.5) | 321 (41.3) | |
| Yes | 1275 (40.0) | 733 (30.5) | 542 (58.7) | |
| Diabetes, n (%) | <0.0001 | |||
| No | 2747 (86.3) | 2136 (94.0) | 611 (71.9) | |
| Yes | 437 (13.7) | 185 (6.0) | 252 (28.1) | |
| Testosterone, n (%) | 0.001 | |||
| Low | 80 (2.5) | 41 (1.6) | 39 (4.6) | |
| Normal | 430 (13.5) | 332 (12.8) | 98 (11.8) | |
| Unknown | 2674 (84.0) | 1948 (85.6) | 726 (83.7) | |
| Total energy (kcal), mean (s.e.) | 2395.2 (25.1) | 2460.7 (28.3) | 2116.8 (43.1) | <0.0001 |
| Dietary niacin (mg), mean (s.e.) | 26.79 (0.3) | 27.60 (0.4) | 23.40 (0.5) | <0.0001 |
BMI: body mass index; PIR: poverty-to-income ratio; CVD: cardiovascular disease; PSM: propensity score matching; s.e.: standard error; ED: erectile dysfunction