Table 4

Crude and adjusted ORs (95% CI) of having hypertension according to parity and gravidity

	Parity			Gravidity
	Model 1*	Model 2†	Model 3‡	Model 1*	Model 2†	Model 3‡
Overall (n=21 634)
0	2.71 (1.71 to 4.28)	1.80 (1.12 to 2.87)	1.71 (1.06 to 2.75)	2.36 (1.44 to 3.86)	1.50 (0.91 to 2.49)	1.44 (0.86 to 2.39)
1	Ref	Ref	Ref	Ref	Ref	Ref
2+	3.54 (2.67 to 4.69)	1.27 (0.95 to 1.71)	1.25 (0.93 to 1.69)	3.44 (2.56 to 4.62)	1.21 (0.89 to 1.65)	1.18 (0.85 to 1.61)
Age ≤45 (n=17 621)
0	1.99 (1.14 to 3.47)	1.33 (0.75 to 2.34)	1.28 (0.72 to 2.27)	2.00 (1.10 to 3.63)	1.28 (0.70 to 2.34)	1.23 (0.67 to 2.27)
1	Ref	Ref	Ref	Ref	Ref	Ref
2+	2.54 (1.86 to 3.48)	1.02 (0.73 to 1.42)	1.08 (0.77 to 1.52)	2.69 (1.91 to 3.78)	1.06 (0.73 to 1.52)	1.12 (0.78 to 1.62)
Age >45 (n=4013)
0	2.48 (0.95 to 6.49)	2.48 (0.95 to 6.50)	2.67 (0.99 to 7.21)	1.18 (0.44 to 3.17)	1.18 (0.44 to 3.18)	1.34 (0.48 to 3.69)
1	Ref	Ref	Ref	Ref	Ref	Ref
2+	1.17 (0.58 to 2.37)	1.17 (0.58 to 2.37)	1.12 (0.54 to 2.30)	0.74 (0.38 to 1.44)	0.74 (0.38 to 1.44)	0.69 (0.35 to 1.36)

*Adjusted for cohort (HEALS, ACE I, ACE II).
†Adjusted for cohort (HEALS, ACE I, ACE II) and age (years).
‡Adjusted for cohort (HEALS, ACE I, ACE II), age (years), years of education (years), formal education (yes, no), land ownership (yes, no), smoking status (yes, no) and BMI (kg/m²).
§Hypertension defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg based on the Joint National Committee 8 guideline.
BMI, body mass index; HEALS, Health Effects of Arsenic Longitudinal Study.