Table 3.

Age-adjusted and multivariable-adjusted hazard ratios and 95% confidence intervals for CHD by ABO blood type and Rh factor type

Cohort	Rh factor		P value	ABO blood group		P value
	Positive	Negative		O	Non-O
NHS
No. of cases/No. of person-years	1453/1163643	465/331107		841/673089	1214/894055
Age-adjusted HR (95% CI)	1.0	1.05(0.94-1.16)	0.40	1.0	1.08(0.99-1.18)	0.07
Multivariate model 1 HR (95% CI)*	1.0	1.03(0.93-1.14)	0.59	1.0	1.10(1.01-1.20)	0.037
Multivariate model 2 HR (95% CI)†	1.0	1.05(0.93-1.18)	0.43	1.0	1.12(1.02-1.24)	0.02
HPFS
No. of cases/No. of person-years	1238/350224	333/94291		833/223128	1182/294184
Age-adjusted HR (95% CI)	1.0	0.88(0.78-1.00)	0.049	1.0	1.10(1.01-1.21)	0.03
Multivariate model 1 HR (95% CI)*	1.0	0.91(0.80-1.03)	0.13	1.0	1.09(1.00-1.20)	0.057
Multivariate model 2 HR (95% CI)†	1.0	0.90(0.79-1.02)	0.095	1.0	1.09(0.99-1.20)	0.06
Combined
Age-adjusted HR (95% CI)	1.0	0.97(0.90-1.06)	0.53	1.0	1.09(1.03-1.17)	0.005
Multivariate model 1 HR (95% CI)	1.0	0.98(0.90-1.06)	0.57	1.0	1.10(1.03-1.17)	0.0045
Multivariate model 2 HR (95% CI)	1.0	0.98(0.90-1.06)	0.58	1.0	1.10(1.03-1.18)	0.004

CHD, coronary heart disease; CI, confidence interval; HPFS, Health Professionals Follow-up Study; HR, hazard ratios; NHS, Nurses’ Health Study.

^*†Adjustment for covariates as described in the footnotes to Table 2.