HIV, Cardiovascular Disease Risk Factors, and Subclinical Atherosclerosis among Kenyan Adults

Abstract

Introduction Greater carotid intimal media thickness (CIMT) and presence of carotid plaque have been validated as measures of subclinical atherosclerosis. HIV is a risk factor for cardiovascular disease (CVD) and has been associated with higher CIMT in North America and Europe. In Sub-Saharan Africa (SSA), there are more people living with HIV (PLHV) on antiretroviral therapy (ARV) and the association of HIV status and CVD risk factors with CIMT has not been well studied. We evaluated these factors in a cohort of PLHV and HIV negative individuals in Western Kenya. Methods In this cross-sectional study, a sub-cohort of 145 PLHV on ARV (≥6 months) and 117 HIV-negative adults accessing community-based services at Kisumu County hospital, underwent bedside measurement of CIMT using carotid ultrasound. Using simple and multivariable linear regression analyses, we examined associations between traditional cardiovascular risk factors, carotid plaque, and mean CIMT, amongst the sub-cohort and then stratified by HIV status. Amongst PLHV, we examined the association between CIMT and HIV related factors, including viral load and CD4 count. Results The HIV negative group had a higher prevalence of several traditional CVD risk factors including older age ≥ 55years (p =0.002), history of hypertension (HTN) (p=0.02), hypertension treatment (p = 0.03) and elevated BP (p = 0.01). The overall mean CIMT in the cohort was 0.42mm (standard deviation [SD] 0.12), and lower in PLHV (0.41mm [SD 0.12] vs HIV negative (0.44mm [SD 0.14], p = 0.02). After adjustment for significant variables in the multivariable regression model, HIV status was not significantly associated with greater mean CIMT (p = 0.19). In the multivariable regression models, amongst PLHV, those with elevated blood pressure or hypertension treatment had a 0.06mm higher mean CIMT (95% confidence interval [CI]; 0.02,0.11, p = 0.002). In the HIV negative group, older age (0.07mm [95%CI; 0.02,0.12] p = 0.006), high total cholesterol (TC) (0.09mm[95%CI: 0.03,0.14] p = 0.01) and diabetes (0.17mm [95%CI:0.03, 0.31] p= 0.02) were associated with higher mean CIMT. The overall prevalence of carotid plaque was low (15/262 [6.0%]), and not significantly different between the two groups (p =0.71). HIV related factors such as CD4 count, viral load, and ARV regimen were not associated with greater CIMT in the simple linear regression models. Conclusion We found no significant association with HIV positive status and subclinical atherosclerosis. When stratified by HIV status, PLHV had fewer CVD risk factors associated with CIMT and HIV- related factors were not significantly associated with CIMT.