Atrial fibrillation and atrial flutter in human immunodeficiency virus-infected persons: incidence, risk factors, and association with markers of HIV disease severity.

OBJECTIVES: The purpose of this study was to investigate the associations of traditional risk factors and longitudinal measures of human immunodeficiency virus (HIV) disease severity with risk of incident atrial fibrillation (AF) in a contemporary cohort of HIV-infected individuals.
BACKGROUND: Cardiovascular disease is common in HIV-infected persons; however, the most common cardiac arrhythmia, AF, has not been adequately studied in this population.
METHODS: We studied a national sample of 30,533 HIV-infected veterans followed in the Veterans Affairs HIV Clinical Case Registry from 1996 to 2011. We examined the independent associations of demographic characteristics, time-updated comorbidities, and time-updated clinical measurements including CD4(+) cell count and viral load with the outcome of incident AF using proportional hazards regression for multivariable analysis.
RESULTS: Over a median follow-up of 6.8 years, 780 (2.6%) patients developed AF. After multivariable adjustment for traditional risk factors, a lower CD4(+) cell count (<200 compared with >350 cells/mm(3); hazard ratio [HR]: 1.4; 95% confidence interval [CI]: 1.1 to 1.8; p = 0.018) and higher viral load (>100,000 compared with <500 copies/ml; HR: 1.7; 95% CI: 1.2 to 2.4; p = 0.002) were independently associated with increased risk of incident AF. Additional risk factors independently associated with risk of AF included older age, White race, coronary artery disease, congestive heart failure, alcoholism, proteinuria, reduced kidney function, and hypothyroidism.
CONCLUSIONS: In a large HIV-infected cohort, markers of HIV disease severity represented by low CD4(+) cell count and high viral load, assessed by multiple time-updated measures, were independently associated with development of AF.