Background and aims

Frailty and cardiovascular disease share many risk factors. We evaluated whether frailty is independently associated with subclinical coronary atherosclerosis and whether any relationships differ by HIV-serostatus.

Methods

We studied 976 [62% HIV-infected] male participants of the Multicenter AIDS Cohort Study who underwent assessment of frailty and non-contrast cardiac CT scanning; of these, 747 men also underwent coronary CT angiography (CCTA). Frailty was defined as having ≥3 of 5 of the following: weakness, slowness, weight loss, exhaustion, and low physical activity. Coronary artery calcium (CAC) was assessed by non-contrast CT, and total plaque score (TPS), mixed plaque score (MPS), and non-calcified plaque score (NCPS) by CCTA. Multivariable-adjusted regression was used to assess the cross-sectional associations between frailty and subclinical coronary atherosclerosis.

Results

Mean (SD) age of participants was 54 (7) years; 31% were black. Frailty existed in 7.5% and 14.3% of HIV-uninfected and HIV-infected men, respectively. After adjustment for demographics, frailty was significantly associated with prevalence of any CAC (CAC>0), any plaque (TPS>0), and mixed plaque (MPS>0) in HIV-uninfected but not in HIV-infected men (p-interaction_HIV<0.05 for all). Among HIV-uninfected men, after adjustment for cardiovascular risk factors, frailty was significantly associated only with CAC>0 [Prevalence Ratio 1.27 (95%CI 1.02, 1.59)] and TPS>0 [1.19 (1.06, 1.35)]. No association was found for NCPS.

Conclusions

Frailty was independently associated with subclinical coronary atherosclerosis among HIV-uninfected men, but not among HIV-infected men. Further work is needed to ascertain mechanisms underlying these differences and whether interventions that improve frailty (i.e. strength training) can improve cardiovascular outcomes.

BACKGROUND:HIV-infected individuals are at increased risk for both sarcopenia and cardiovascular disease. Whether an association between low muscle mass and subclinical coronary artery disease (CAD) exists, and if it is modified by HIV serostatus, are unknown. METHODS:We performed cross-sectional analysis of 513 male MACS participants (72% HIV-infected) who underwent mid-thigh computed tomography (CT) and non-contrast cardiac CT for coronary artery calcium (CAC) during 2010-2013. Of these, 379 also underwent coronary CT angiography for non-calcified coronary plaque (NCP) and obstructive coronary stenosis ≥50%. Multivariable-adjusted Poisson regression was used to estimate prevalence risk ratios of associations between low muscle mass (<20th percentile of the HIV-uninfected individuals in the sample) and CAC, NCP and obstructive stenosis. RESULTS:The prevalence of low thigh muscle mass was similar by HIV serostatus (20%). There was no association of low muscle mass with CAC or NCP. However, low thigh muscle mass was significantly associated with a 2.5-fold higher prevalence of obstructive coronary stenosis, after adjustment for demographics and traditional CAD risk factors [PR 2.46 (95% CI 1.51, 4.01)]. This association remained significant after adjustment for adiposity, inflammation, and physical activity. There was no significant interaction by HIV serostatus (p-interaction = 0.90). CONCLUSIONS:In this exploratory analysis, low thigh muscle mass was significantly associated with subclinical obstructive coronary stenosis. Additional studies involving larger sample sizes and prospective analyses are needed to confirm the potential utility of measuring mid-thigh muscle mass for identifying individuals at increased risk for obstructive CAD who might benefit from more aggressive risk factor management.