Abstract
OBJECTIVES: The aim of this study was to determine the incidence and clinical characteristics of sudden cardiac death (SCD) in patients with human immunodeficiency virus (HIV) infection.
BACKGROUND: As the HIV-infected population ages, cardiovascular disease prevalence and mortality are increasing, but the incidence and features of SCD have not yet been described.
METHODS: The records of 2,860 consecutive patients in a public HIV clinic in San Francisco between April 2000 and August 2009 were examined. Identification of deaths, causes of death, and clinical characteristics were obtained by search of the National Death Index and/or clinic records. SCDs were determined using published retrospective criteria: 1) the International Classification of Diseases-10th Revision, code for all cardiac causes of death; and (2) circumstances of death meeting World Health Organization criteria.
RESULTS: Of 230 deaths over a median of 3.7 years of follow-up, 30 (13%) met SCD criteria, 131 (57%) were due to acquired immune deficiency syndrome (AIDS), 25 (11%) were due to other (natural) diseases, and 44 (19%) were due to overdoses, suicides, or unknown causes. SCDs accounted for 86% of all cardiac deaths (30 of 35). The mean SCD rate was 2.6 per 1,000 person-years (95% confidence interval: 1.8 to 3.8), 4.5-fold higher than expected. SCDs occurred in older patients than did AIDS deaths (mean 49.0 vs. 44.9 years, p = 0.02). Compared with AIDS and natural deaths combined, SCDs had a higher prevalence of prior myocardial infarction (17% vs. 1%, p < 0.0005), cardiomyopathy (23% vs. 3%, p < 0.0005), heart failure (30% vs. 9%, p = 0.004), and arrhythmias (20% vs. 3%, p = 0.003).
CONCLUSIONS: SCDs account for most cardiac and many non-AIDS natural deaths in HIV-infected patients. Further investigation is needed to ascertain underlying mechanisms, which may include inflammation, antiretroviral therapy interruption, and concomitant medications.