Table 3. Subgroup analyses of hypertension and endometrial cancer.
| Hypertension and endometrial cancer | ||||||
|---|---|---|---|---|---|---|
| n | Relative risk (95% CI) | I2 (%) | Ph1 | Ph2 | ||
| All studies | 25 | 1.61 (1.41–1.85) | 86.3 | <0.0001 | ||
| Cohort studies | 6 | 1.32 (1.12–1.56) | 47.4 | 0.09 | 0.21 | |
| Case-control studies | 19 | 1.73 (1.45–2.06) | 89.1 | <0.0001 | ||
| Duration of follow-up (cohort studies) | ||||||
| <10 years | 1 | 1.50 (0.85–2.64) | 0.72 | |||
| ≥10 years | 5 | 1.31 (1.09–1.57) | 57.0 | 0.05 | ||
| Geographic location | ||||||
| Europe | 7 | 1.68 (1.29–2.20) | 81.5 | <0.0001 | 0.33 | |
| America | 14 | 1.38 (1.24–1.55) | 69.6 | <0.0001 | ||
| Asia | 4 | 2.61 (1.08–6.33) | 89.9 | <0.0001 | ||
| Number of cases | ||||||
| <250 | 11 | 1.77 (1.52–2.06) | 11.2 | 0.34 | 0.63 | |
| 250–<500 | 7 | 1.41 (1.10–1.81) | 82.4 | <0.0001 | ||
| ≥500 | 7 | 1.64 (1.27–2.12) | 94.5 | <0.0001 | ||
| Exclusion of prevalent hysterectomies and/or censoring of incident hysterectomies | ||||||
| Yes | 16 | 1.51 (1.28–1.78) | 88.5 | <0.0001 | 0.32 | |
| No | 9 | 1.81 (1.49–2.20) | 56.5 | 0.02 | ||
| Study quality | ||||||
| 0–3 points | 0 | 0.05 | ||||
| 4–6 | 6 | 2.17 (1.38–3.40) | 91.1 | <0.0001 | ||
| 7–9 | 19 | 1.43 (1.27–1.60) | 73.8 | <0.0001 | ||
| Adjustment for confounding factors3 | ||||||
| Age | Yes | 25 | 1.61 (1.41–1.85) | 86.3 | <0.0001 | NC |
| No | 0 | |||||
| Smoking | Yes | 9 | 1.26 (1.13–1.40) | 58.2 | 0.01 | 0.02 |
| No | 16 | 1.93 (1.52–2.45) | 86.5 | <0.0001 | ||
| Diabetes mellitus | Yes | 10 | 1.56 (1.21–2.02) | 77.2 | <0.0001 | 0.78 |
| No | 15 | 1.65 (1.39–1.97) | 89.7 | <0.0001 | ||
| BMI | Yes | 15 | 1.27 (1.16–1.40) | 54.3 | 0.006 | 0.003 |
| No | 10 | 2.15 (1.62–2.86) | 85.6 | <0.0001 | ||
| Physical activity | Yes | 3 | 1.27 (0.88–1.81) | 62.8 | 0.07 | 0.35 |
| No | 22 | 1.66 (1.44–1.93) | 87.5 | <0.0001 | ||
| Oral contraceptive use | Yes | 7 | 1.23 (1.06–1.44) | 61.4 | 0.02 | 0.02 |
| No | 18 | 1.86 (1.53–2.25) | 89.3 | < 0.0001 | ||
| Hormone replacement therapy | Yes | 9 | 1.34 (1.11–1.63) | 81.4 | < 0.0001 | 0.08 |
| No | 16 | 1.84 (1.50–2.27) | 88.6 | < 0.0001 | ||
| Age at menarche | Yes | 8 | 1.48 (1.15–1.91) | 83.4 | < 0.0001 | 0.49 |
| No | 17 | 1.69 (1.42–2.02) | 87.9 | < 0.0001 | ||
| Parity | Yes | 11 | 1.33 (1.16–1.54) | 59.7 | 0.006 | 0.03 |
| No | 14 | 1.93 (1.55–2.41) | 91.3 | < 0.0001 | ||
| Age at menopause | Yes | 3 | 1.14 (1.01–1.30) | 0 | 0.38 | 0.07 |
| No | 22 | 1.72 (1.47–2.02) | 87.5 | < 0.0001 | ||
| Menopausal status | Yes | 3 | 1.40 (1.03–1.89) | 76.8 | 0.01 | 0.49 |
| No | 22 | 1.66 (1.42–1.93) | 87.3 | < 0.0001 | ||
n denotes the number of studies, 1P for heterogeneity within each subgroup, 2P for heterogeneity between subgroups with meta-regression analysis. NC, not calculable because no studies were present in one of the subgroups.