Table 2.
Multivariable hazard ratios (HR) and 95% confidence intervals (CI) of incident T2DM by number of parity until phase VI (2015–2018): Tehran Lipid and Glucose Study
| E/N | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | ||
| Parity (continuous variable) | |||||||||||
| Per each additional | 557/2552 | 1.10 (1.05–1.16) | < 0.001 | 1.10 (1.04–1.15) | < 0.001 | 1.09 (1.04–1.15) | 0.001 | 1.05 (1.00–1.11) | 0.075 | 1.04 (0.99–1.10) | 0.108 |
| Number of parity | |||||||||||
| 1 | 19/180 | 1 | 1 | 1 | 1 | 1 | |||||
| 2 | 99/614 | 1.48 (0.90–2.41) | 0.121 | 1.48 (0.91–2.43) | 0.116 | 1.48 (0.90–2.42) | 0.119 | 1.41 (0.86–2.31) | 0.172 | 1.39 (0.85–2.27) | 0.193 |
| 3 | 128/640 | 1.74 (1.07–2.83) | 0.025 | 1.75 (1.07–2.86) | 0.025 | 1.73 (1.06–2.83) | 0.028 | 1.54 (0.94–2.52) | 0.084 | 1.50 (0.92–2.45) | 0.107 |
| ≥ 4 | 311/1118 | 2.28 (1.40–3.70) | 0.001 | 2.27 (1.39–3.72) | 0.001 | 2.23 (1.36–3.65) | 0.001 | 1.72 (1.05–2.83) | 0.031 | 1.64 (1.00–2.70) | 0.051 |
| P value for trend | < 0.001 | < 0.001 | < 0.001 | 0.027 | 0.055 | ||||||
Model 1: Adjusted for age. Model 2: Adjusted for age, education level, low physical activity, family history of diabetes, systolic and diastolic blood pressure, and anti-hypertensive medications usage. Model 3: Model 2 + further adjusted for history of macrosomia, preeclampsia, and oral contraceptive pill (OCP) usage. Model 4: Model 3 + further adjusted for body mass index and waist circumference. Model 5: Model 4 + further adjusted for triglyceride/ high-density lipoprotein cholesterol. T2DM: type 2 diabetes mellitus; E: event; N: number