“As part of my ongoing research in 2010, we were fully investigating every instance of sudden death in San Francisco,” Dr. Zian H. Tseng from University of California-San Francisco (UCSF), San told Reuters Health in an email. “I noticed that many sudden deaths involved individuals with HIV infection.”
“I wondered if there was some sort of connection,” Dr. Tseng continued. “Therefore I posed this question to Priscilla Hsue, MD, a UCSF associate professor of medicine and the director of the HIV Cardiology Clinic at San Francisco General Hospital and Trauma Center (SFGH), who is one of a few cardiologists in the country who specializes in HIV. To her knowledge, no one had ever explored the link between HIV and sudden death, and that is when we began our collaboration.”
Along with colleagues, Dr. Tseng and Dr. Hsue investigated the incidence, clinical characteristics, and predictors of SCD over the past decade among 2860 consecutive adult patients with documented HIV infection.
Thirty (13%) of 230 deaths occurring over a median of 3.7 years of follow-up met criteria for SCDs. SCDs accounted for 30 of 35 (86%) of all cardiac deaths. These figures translated into a mean SCD rate during the decade of 2.6 per 1000 person-years (compared with 11.4 per 1000 person-years for AIDS death).
“The fact that the vast majority of cardiac deaths were sudden is surprising and implies that we as clinicians need to be aware of this potential health issue among patients with HIV,” Dr. Tseng said.
The SCD mortality rate among HIV patients is 4.46-fold higher than the expected rate based on that for the entire San Francisco population.
Four in five patients with SCD had either known cardiovascular disease or cardiovascular disease risk factors, and a third of the patients reported symptoms of chest pain, palpitations, syncope, and/or dyspnea at their final clinic visits.
HIV patients dying of SCD had a higher prevalence of prior myocardial infarction, cardiomyopathy, heart failure, arrhythmias, hypertension, and hyperlipidemia, compared with patients dying of AIDS and other natural causes combined, but they had a similar prevalence of diabetes, chronic renal disease, and chronic pulmonary disease.
“Given that cardiac symptoms were common in victims of SCD, aggressive primary prevention of cardiovascular disease should be considered in HIV-infected patients, especially those with traditional risk factors,” the researchers conclude. “As we seek to reduce mortality in an aging HIV-infected population, greater attention must be directed to the mechanisms underlying SCD, with the goal of identifying at-risk patients and ultimately preventing sudden death.”
“Many questions remain to be answered in light of our study and highlight the difficulties with retrospective observational studies of deaths,” Dr. Tseng said. “Although we cross-checked multiple records, how many of these SCDs were not actually cardiac? What is the contribution of unmeasured factors such as drug use or occult overdoses (which are known to be high in HIV patients)? What are the risk factors for sudden death in this setting and how should they be addressed? What is the role of antiretroviral drugs and inflammation? What is the role of preventive procedures such as implantable cardioverter defibrillator implantation in HIV patients at high risk for SCD?”
“These and many further questions we hope to answer in our ongoing prospective studies on SCD in the setting of HIV,” Dr. Tseng said.