CONTEXT: The relationship of ischaemic heart disease (IHD) with androgenic alopecia (AGA) has been demonstrated, but no differentiation between early and late onsets of alopecia with regard to the risk and severity of IHD has been made. OBJECTIVE: To test if the early onset of alopecia is a risk factor for early severe, coronary artery disease (CAD) requiring surgery and to test if the early onset of AGA differs in this respect from the late onset of AGA. DESIGN: Population-based case-control study. SETTING AND PARTICIPANTS: All the 85 male persons living on 31 December 1999 in a Finnish town with total population of 7200, who had had a coronary revascularization procedure between March 1987 and January 1999, were drawn from the discharge register. For each case, an individually selected age-matched control person living in the same town was drawn from the official census register. MAIN OUTCOME MEASURE: Alopecia defined as grade 3 vertex or more on the alopecia classification scale of Hamilton, modified by Norwood South Med J, 68:1359-1365, 1975. RESULTS: The unadjusted odds ratio (OR) for coronary revascularization under the age of 60 years was 3.57 (95% confidence interval (CI) 1.19-10.72) in men with an early onset of AGA compared with men with normal hair status or late AGA. After multivariate adjustment for the traditional CAD risk factors, the corresponding OR was 3.18 (95% CI, 1.01-10.03). The unadjusted OR for the coronary revascularization procedure at any age was 2.14 (95% CI, 1.08-4.23) in the subgroup of the men with early AGA compared to those with late AGA or normal hair status. After adjustment for traditional risk factors this OR was 1.84, being nearly significant (95% CI, 0.90-3.77). CONCLUSION: Our results support the hypothesis that the early onset of AGA is a risk factor for an early onset of severe coronary heart disease.