Sex-based differences in risk factors for incident myocardial infarction and stroke in the UK Biobank

AIM: This study examined sex-based differences in associations of vascular risk factors with incident cardiovascular events in the UK Biobank. METHODS: Baseline participant demographic, clinical, laboratory, anthropometric, and imaging characteristics were collected. Multivariable Cox regression was used to estimate independent associations of vascular risk factors with incident myocardial infarction (MI) and ischaemic stroke for men and women. Women-to-men ratios of hazard ratios (RHRs), and related 95% confidence intervals, represent the relative effect-size magnitude by sex. RESULTS: Among the 363 313 participants (53.5% women), 8470 experienced MI (29.9% women) and 7705 experienced stroke (40.1% women) over 12.66 11.93, 13.38 years of prospective follow-up. Men had greater risk factor burden and higher arterial stiffness index at baseline. Women had greater age-related decline in aortic distensibility. Older age RHR: 1.02 (1.01-1.03), greater deprivation RHR: 1.02 (1.00-1.03), hypertension RHR: 1.14 (1.02-1.27), and current smoking RHR: 1.45 (1.27-1.66) were associated with a greater excess risk of MI in women than men. Low-density lipoprotein cholesterol was associated with excess MI risk in men RHR: 0.90 (0.84-0.95) and apolipoprotein A (ApoA) was less protective for MI in women RHR: 1.65 (1.01-2.71). Older age was associated with excess risk of stroke RHR: 1.01 (1.00-1.02) and ApoA was less protective for stroke in women RHR: 2.55 (1.58-4.14). CONCLUSION: Older age, hypertension, and smoking appeared stronger drivers of cardiovascular disease in women, whereas lipid metrics appeared stronger risk determinants for men. These findings highlight the importance of sex-specific preventive strategies and suggest priority targets for intervention in men and women.