A recent analysis of hypertension rates suggested that incidence among HIV patients has more than tripled from 1996 through 2013 and are accompanied by an increase in several hypertension risk determinants such as obesity or diabetes, reports Healio. “In addition to the expected increases in major cardiovascular disease (CVD) events among HIV infected persons given changing population demographics, evidence also suggests that HIV infection itself may contribute to an increased risk of major CDV events,” the researchers wrote. “For these reasons, improving our understanding of the epidemiology of established CVD risk determinants in HIV-infected persons, and how these determinants impact cardiovascular health in the context of the chronic immune activation unique to HIV infection is of heightened importance.”
Although previous analyses have assessed CVD rates among HIV patients, hypertension data following widespread adoption of metabolically safer ART are limited, the researchers wrote. To detail outcomes in this population, they examined the electronic and administrative health records of 3,612 HIV patients enrolled in the University of North Carolina Centre for AIDS Research HIV Clinical Cohort (UCHCC) from 1996 through 2013.
Along with basic demographic information and insurance status, the researchers collected data on various comorbidities and other known determinants of cardiovascular health. These were analysd against the study’s primary outcome of interest – annual incidence of hypertension – to identify potential relationships among the HIV population.
The median age of the study cohort was 36 years: 59% were non-Hispanic blacks, 71% were male, and 41% were men who have sex with men. Further, 42% were uninsured, 41% currently or formerly used tobacco, and 18% were co-infected with hepatitis C virus. Median nadir CD4 among the cohort was 173 cells/mm3 and 471 patients had a documented diagnosis of hypertension at baseline.
Un-adjusted annual incidence of hypertension was 3.44 cases per 100 person-years (95% CI, 3.2-3.7), but increased from 1.68 cases per 100 person-years in 1996 to 5.38 cases per 100 person-years in 2013 (P < .001). This effect persisted when annual estimates were standardised for age (P = .02). In addition, hypertension rates were greater among patients who were obese (IRR = 1.7; 95% CI, 1.43-2.02), as well as among those with diabetes (IRR = 1.44; 95% CI, 1.14-1.83) and renal insufficiency (IRR = 1.36; 95% CI, 1.16-1.61).
Hypertension incidence was decreased, however, among those with CD4 nadirs of 500 cells/mm3 or more (IRR = 0.73; 95% CI, 0.53-1.01).
While these findings confirm the impact of several traditional hypertension risk factors on HIV patients, they also suggest a potential association between viral load suppression and reduced incidence of hypertension, according to the researchers.
“Although there was no definitive linear trend between CD4 nadir count and incident hypertension diagnoses, data from our cohort suggest that persons who maintain CD4 counts above 500 cells/mm3 for the duration of infection have a lower incidence of hypertension,” they wrote. “Taken together, our findings present more evidence in support of early ART for all persons with HIV and further emphasises the importance of high quality CVD primary preventive care in this high risk population.”
Background: HIV-infected persons are at higher risk for major cardiovascular disease (CVD) events than uninfected persons. Understanding the epidemiology of major traditional CVD risk determinants, particularly hypertension, in this population is needed.
Methods: The study population included HIV-infected patients participating in the UNC CFAR HIV Clinical Cohort from 1996 to 2013. Annual incidence rates of hypertension were calculated. Multivariable Poisson models were fit to identify factors associated with incident hypertension.
Results: 3,141 patients contributed 21,956 person-years (PY) of follow-up. Overall, 57% patients were Black, 28% were women, and the median age was 35 years. Hypertension age-standardized incidence rates increased from 1.68 cases per 100 PYs in 1996 to 5.35 cases per 100 PYs in 2013 (P <0.001). In adjusted analyses, hypertension rates were higher among obese patients (incidence rate ratio [IRR] 1.70, 95% confidence interval [CI] 1.43-2.02), and those with diabetes mellitus (IRR 1.44, 95% CI 1.14-1.83) and renal insufficiency (IRR 1.36, 95% CI 1.16-1.61), but lower among patients with a CD4 nadir of≥500 cells/mm3 (IRR 0.73, 95% CI 0.53-1.01).)
Conclusions: The incidence of hypertension increased from 1996 to 2013, alongside increases in traditional hypertension risk determinants. Notably, HIV-related immunosuppression and ongoing viral replication may contribute to an increased hypertension risk. Aggressive CVD risk factor management, early HIV diagnosis, linkage to care, antiretroviral therapy initiation, and durable viral suppression, will be important components of a comprehensive primary CVD prevention strategy in HIV-infected persons.