Mind the gap: difference between Framingham heart age and real age increases with age in HIV-positive individuals-a clinical cohort study

Objectives To measure the excess risk of cardiovascular disease (CVD) in HIV-positive individuals by comparing heart age' with real age and to estimate associations of patients' characteristics with heart age deviation (heart age-real age). Design Clinical Cohort Study. Setting Bristol HIV clinic, Brecon Unit at Southmead Hospital, Bristol, UK. Participants 749 HIV-positive adults who attended for care between 2008 and 2011. Median age was 42years (IQR 35-49), 67% were male and 82% were treated with antiretroviral therapy. Main outcome measures We calculated the Framingham 10-year risk of CVD and traced back to heart age', the age of an individual with the same score but ideal risk factor values. We estimated the relationship between heart age deviation and real age using fractional polynomial regression. We estimated crude and mutually adjusted associations of sex, age, CD4 count, viral load/treatment status and period of starting antiretroviral therapy with heart age deviation. Results The average heart age for a male aged 45years was 48years for a non-smoker and 60years for a smoker. Heart age deviation increased with real age and at younger ages was smaller for females than males, although this reversed after 48years. Compared to patients with CD4 count <500 cells/mm(3), heart age deviation was 2.4 (95% CI 0.7 to 4.0) and 4.3 (2.3 to 6.3) years higher for those with CD4 500-749 cells/mm(3) and 750 cells/mm(3), respectively. Conclusions In HIV-positive individuals, the difference between heart age and real age increased with age and CD4 count and was very dependent on smoking status. Heart age could be a useful tool to communicate CVD risk to patients and the benefits of stopping smoking.