Table 2.
Baseline characteristics of study population by serum total bilirubin quartiles in women before and after propensity score matching
| Total bilirubin quartiles in women (Before matching) | Total bilirubin quartiles in women (After matching) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Q1 (≤ 0.38) | Q2 (0.39–0.49) | Q3 (0.50–0.65) | Q4 (≥ 0.66) | P-value | Q1 (≤ 0.38) | Q2 (0.39–0.49) | Q3 (0.50–0.65) | Q4 (≥ 0.66) | P-value | |
| n | 544 | 510 | 532 | 510 | 326 | 326 | 326 | 326 | ||
| Age (years) | 52.5 (8.8) | 51.5 (8.5) | 49.8 (8.3) | 48.9 (8.1) | < 0.001 | 49.2 (7.4) | 49.5 (8.1) | 49.3 (7.6) | 49.2 (8.0) | 0.957 |
| Waist circumference (cm) | 79.7 (8.7) | 78.5 (8.6) | 77.6 (8.8) | 76.9 (8.2) | < 0.001 | 77.7 (7.7) | 77.3 (7.9) | 77.5 (8.0) | 77.7 (7.9) | 0.912 |
| Systolic BP (mmHg) | 116.8 (16.7) | 115.3 (16.5) | 114.5 (17.0) | 110.9 (14.8) | < 0.001 | 112.7 (14.2) | 114.2 (15.4) | 114.5 (16.9) | 112.0 (13.8) | 0.1 |
| Diastolic BP (mmHg) | 76.0 (10.0) | 75.9 (10.4) | 75.7 (10.9) | 74.0 (9.7) | 0.005 | 74.9 (9.4) | 76.0 (9.9) | 76.0 (11.2) | 74.6 (9.3) | 0.129 |
| Mean arterial BP (mmHg) | 89.6 (11.6) | 89.0 (11.9) | 88.6 (12.5) | 86.3 (10.9) | < 0.001 | 87.5 (10.5) | 88.7 (11.3) | 88.8 (12.7) | 87.1 (10.3) | 0.104 |
| Fasting plasma glucose (mg/dL) | 81.3 (8.5) | 81.6 (12.6) | 81.2 (11.6) | 81.0 (13.2) | 0.862 | 81.3 (9.3) | 81.5 (9.8) | 81.3 (13.3) | 81.1 (13.2) | 0.98 |
| Postprandial plasma glucose (mg/dL) | 114.5 (30.1) | 117.3 (35.8) | 120.3 (32.0) | 120.4 (36.2) | 0.010 | 113.3 (30.0) | 116.0 (33.2) | 119.8 (30.7) | 121.9 (38.3) | 0.005 |
| HbA1c | 5.60 (0.55) | 5.58 (0.62) | 5.49 (0.49) | 5.45 (0.62) | < 0.001 | 5.6 (0.5) | 5.5 (0.4) | 5.5 (0.5) | 5.5 (0.6) | 0.027 |
| HOMA-IR | 1.48 (1.14–2.06) | 1.41 (1.04–1.86) | 1.35 (1.01–1.72) | 1.27 (0.87–1.74) | < 0.001 | 1.5 (1.1–2.1) | 1.4 (1.0-1.9) | 1.4 (1.0-1.7) | 1.2 (0.9–1.7) | < 0.001 |
| Total cholesterol (mg/dL) | 185.9 (32.0) | 188.7 (33.6) | 189.6 (35.1) | 189.0 (34.6) | 0.304 | 182.4 (32.5) | 187.8 (34.5) | 189.0 (34.0) | 189.8 (36.5) | 0.028 |
| Triglyceride (mg/dL) | 111 (90–140) | 109 (86–135) | 104 (85–131) | 102 (83–128) | 0.001 | 106.0 (87–130) | 109.0 (84–134) | 103.0 (88–128) | 104.0 (86–131) | 0.443 |
| HDL-cholesterol (mg/dL) | 48.9 (10.1) | 49.3 (9.9) | 49.9 (9.9) | 49.0 (10.2) | 0.412 | 48.9 (10.0) | 49.5 (9.7) | 49.4 (9.9) | 48.3 (9.7) | 0.348 |
| AST (U/L) | 24 (21–28) | 25 (21–28) | 24 (21–28) | 24 (21–30) | 0.449 | 23.0 (21–27) | 24.0 (21–28) | 24.0 (22–28) | 24.0 (22–30) | < 0.001 |
| ALT (U/L) | 19 (16–24) | 19 (16–24) | 18 (15–24) | 19 (15–24) | 0.457 | 18.0 (15–24) | 18.5 (15–22) | 18.0 (16–22) | 19.0 (16–24) | 0.212 |
| Current smoker (%) a | 5.71 | 3.8 | 2.5 | 1.8 | < 0.001 | 6.3 | 3.1 | 2.8 | 0.9 | 0.02 |
| Regular drinker (%) b | 27.9 | 26.9 | 34.5 | 31.4 | 0.022 | 32.3 | 28.5 | 33.3 | 30.2 | 0.463 |
| Regular exercise (%) c | 21.5 | 23.2 | 24.2 | 28.0 | 0.071 | 22.3 | 24.2 | 25.7 | 28.6 | 0.3 |
| Family history of diabetes (%) | 10.3 | 12.9 | 14.5 | 14.5 | 0.094 | 11.3 | 14.4 | 16.0 | 12.9 | 0.242 |
Data are expressed as the mean (SD), median (IQR) or percentage
Propensity score matched for age (years), fasting plasma glucose (mg/dL), systolic BP (mmHg), diastolic BP (mmHg), waist circumference (cm), triglyceride (mg/dL), HDL-cholesterol (mg/dL)
Abbreviations: BP, blood pressure; HbA1c, glycated hemoglobin; HOMA-IR, homeostatic model assessment for insulin resistance; HDL, high density lipoprotein; AST, aspartate aminotransferase; ALT, alanine aminotransferase
P-values were calculated with the use of ANOVA-test or chi-square test
aAn adult who has smoked 100 cigarettes in his or her lifetime and who currently smokes cigarettes
bAlcohol intake ≥ once/month
cModerate intensity physical exercise ≥ three times/week