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.
