Subclinical cardiovascular disease and risk of incident frailty: The British Regional Heart Study

Background/objectives: Subclinical cardiovascular disease (CVD) is cross-sectionally associated with frailty, but the relationship between subclinical CVD and incident frailty has not been reported. We aimed to assess this prospective association. Design: Longitudinal analysis of data from the British Regional Heart Study, a prospective cohort study. Participants: 1057 men, aged 71-92 years, robust or pre-frail at baseline, and without a clinical diagnosis of CVD. Measurements: Participants underwent baseline measurement of carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (CIMT), carotid distensibility coefficient (DC), and ankle-brachial pressure index (ABPI), and had questionnaire-based frailty assessment after three years. Frailty status was based on the Fried phenotype. Multivariate logistic regressions examined associations between incident frailty and tertile of cfPWV, CIMT, DC, and ABPI group (<0.9, 0.9-1.4, >= 1.4). Results: 865 men were examined and completed the 3 year follow-up questionnaire, of whom 78 became frail. Adjusted for age, prefrailty, body mass index, diabetes, smoking, atrial fibrillation, blood pressure, renal function, and incident CVD, higher CIMT was associated with greater odds of incident frailty (2nd tertile OR 1.62, 95% CI 0.78-3.35, 3rd tertile OR 2.61, 95% CI 1.30-5.23, p = 0.007, trend p = 0.006). cfPWV showed a weaker, non-significant association (2nd tertile OR 1.79, 95% CI 0.85-3.78, 3rd tertile OR 1.73, OR 0.81-3.72, p = 0.16, trend p = 0.20). There was no clear association between incident frailty and DC or ABPI. In subgroup analyses, CIMT was significantly associated with incident frailty in men 80 years (3rd tertile OR 6.99, 95%CI 1.42-34.5), but not in men aged 75-80 or < 75 years. Conclusion: Subclinical CVD, as measured by CIMT, is associated with greater risk of incident frailty in older men over three year follow-up, independent of the development of clinically-apparent stroke, heart failure, or myocardial infarction, and may be a modifiable risk factor for frailty. This association may be stronger in very old age.