Smoking, alcohol consumption, physical activity, and family history and the risks of acute myocardial infarction and unstable angina pectoris: a prospective cohort study

Table 6 Multivariable Adjusted Rate Ratios for Family History in the CAREMA Cohort, 1987-2003

	Acute Myocardial Infarction			Unstable Angina Pectoris
	Cases/person-years	RR	95% CI	Cases/person-years	RR	95% CI	Pheterogeneity^a
Number of parents affected
No parents affected	253/147,248	1	reference	148/147,248	1	reference
One parent affected	144/56,391	1.34	1.09, 1.65	106/56,391	1.70	1.32, 2.18
Both parents affected	25/6,000	1.79	1.18, 2.71	19/6,000	2.22	1.37, 3.59	0.33
P trend			<0.001			<0.001
Age at diagnosis of parents
No parents affected	253/147,248	1	reference	148/147,248	1	reference
Non-premature MI	80/29,244	1.16	0.90, 1.50	68/29,244	1.62	1.21, 2.16
Premature MI^b	89/33,146	1.70	1.33, 2.17	57/33,146	1.97	1.44, 2.69	0.16
P trend			<0.001			<0.001
Number of parents affected including age at diagnosis
No parents affected	253/147,248	1	reference	148/147,248	1	reference
One parent affected, non-premature MI	74/27,105	1.18	0.91, 1.53	61/27,105	1.60	1.18, 2.16
Both parents affected, both non-premature MI	6/2,139	1.03	0.46, 2.33	7/2,139	1.79	0.83, 3.83
One parent affected, premature MI	70/29,285	1.58	1.21, 2.06	45/29,285	1.85	1.32, 2.60
Both parents affected, one premature MI	17/2,279	3.04	1.85, 4.99	8/2,279	2.42	1.19, 4.96
Both parents affected, both premature MI	2/1,582	0.78	0.19, 3.13	4/1,582	2.94	1.08, 7.99	0.51
P trend			<0.001			<0.001

CI, confidence interval; MI, myocardial infarction; RR, rate ratio. Rate ratios adjusted for age at baseline (years), sex, baseline cohort (PPHVZ or MORGEN), smoking status (never, ex- or current smoker), smoking frequency (cigarettes/day), smoking duration (years), total alcohol consumption (glasses/day), total and HDL cholesterol levels (mmol/L), diabetes mellitus (yes/no), systolic blood pressure (mmHg), and body mass index (kg/m²).
Table summary: A positive family history is associated with increased risks of both AMI and UAP, especially when both parents are affected or when they are diagnosed at a younger age (premature MI). These associations seemed to be stronger for the risk of UAP than of AMI but the differences were not statistically significant (p heterogeneity > 0.05).
^a Heterogeneity test for the difference in the RRs between AMI and UAP.
^b Defined as age at diagnosis of MI ≤60 years for the father and ≤65 years for the mother. If both parents were affected, at least one parent had a premature MI.