Individuals with HIV infection who have either increased viral loads or decreased CD4 cell counts may be at an increased risk for sudden cardiac death (SCD), according to results of an observational, longitudinal cohort study published in the Journal of the American Heart Association.
Researchers at Vanderbilt University Medical Center in Nashville sourced data on veterans with (n=43,497) and without (n=100,929) HIV infection who were enrolled in the Veterans Aging Cohort Study between 2003 and 2014. The researchers sought to determine whether HIV infection is an independent risk factor for SCD. Participants were matched in a 1:2 fashion on the basis of age, sex, ethnicity, clinical site, and enrollment year. Participants were followed until their first SCD event or other death event, or until December 2014. .
Participants in the HIV-positive and HIV-negative cohorts comprised 97.2% and 97.2% men, had a mean age of 49.2 ± 10.7 and 50.1 ± 10.6 years, and 48.0% and 47.0% were Black, respectively. Among participants in the HIV-positive cohort, 39.5% were on antiretroviral therapy at baseline, median HIV-1 RNA concentrations were 999 copies/mL, and CD4 cell counts were 385 cells/mm3.
During the study, the rates of SCD were 232 (95% CI, 215-249) and 234 (95% CI, 224-246) per 100,000 person-years among participants in the HIV-positive and HIV-negative cohorts, respectively.
After stratification by baseline HIV control status, participants with HIV viral loads greater than or equal to 500 copies/mL and those with CD4 cell counts less than 200 cells/mm3 had a 17% and 29% increased risk for SCD, respectively, compared with those without HIV infection.
In a time-varying analysis of participants in the HIV-positive cohort, the researchers noted an association between those with viral loads greater than or equal to 500 copies/mL (adjusted hazard ratio [aHR], 1.70; 95% CI, 1.46-1.98) or those with CD4 cell counts less than 200 cells/mm3 (aHR, 1.57; 95% CI, 1.28-1.92) and an increased risk for SCD.
Additional risk factors for SCD among participants in both cohorts included age, male gender, cardiovascular disease, hypertension, increased LDL-cholesterol, active smoker status, hepatitis C virus, increased BMI, anemia, alcohol use disorder, diabetes, and chronic obstructive pulmonary disease (P <.05).
Differential risk factors between participants in both cohorts included minority ethnicity among those in the HIV-positive cohort (HR, 1.73; 95% CI, 1.16-2.59) and diabetes among those in the HIV-negative cohort (HR, 1.44; 95% CI, 1.30-1.59).
This study may have been limited by its lack of access to autopsy data, as that is the gold standard diagnosis for SCD. The World Health Organization has stated that nearly half of SCDs diagnosed without these data may not in fact be cardiac-related.
The researchers concluded that in addition to standard SCD risk factors, individuals with poorly controlled HIV infection may be at an increased risk for SCD.
Freiberg MS, Duncan MS, Alcorn C, et al. HIV infection and the risk of World Health Organization-defined sudden cardiac death. J Am Heart Assoc. 2021;e021268. doi:10.1161/JAHA.121.021268