Highest Stroke Incidence Among Women, Blacks Living with HIV

Felicia Chow, MD, board-certified neurologist and neuro-infectious disease specialist at the University of California San Francisco

Felicia Chow, MD

Rates of stroke are higher among people living with HIV (PLWH) compared with age-matched HIV-negative patients, and this increased risk of stroke has been observed in numerous studies.

Since these studies relied largely upon data from electronic medical records and did not follow patients at regular intervals, the potential for incomplete and inaccurate information remains.

Felicia Chow, MD, a board-certified neurologist and neuro-infectious disease specialist at the University of California San Francisco, collaborated with several colleagues and investigated the incidence of first-ever stroke/transient ischemic attack (TIA) and associated risk factors in a cohort of persons living with HIV infection (PLWH).

The study authors utilized the AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) study, a cohort study of HIV-infected subjects prospectively randomized into selected clinical trials for antiretroviral (ARV) treatment-naïve and ARV treatment-experienced individuals.

This prospective, observational cohort study followed patients at a minimum of once every 12 weeks until the completion of the parent protocol and then every 16 weeks thereafter. Patients were excluded if they experienced a stroke prior to the study.

The primary endpoint of the study was a composite of first-ever stroke or TIA. Other data collected during the study included hypertensive status, low density lipoprotein (LDL) cholesterol levels, statin use (previous 12 months), previous myocardial infarction (MI), history of diabetes mellitus, smoking status, BMI, waist circumference, renal function, hepatitis C virus (HCV) infection status and history of intravenous drug use. Malignancies of the central nervous system (CNS) were also noted.

A total of 6933 patients were included in the analysis, of which 20% were women and 37% were non-Hispanic black, and the median age was 37 years.

A higher stroke rate was associated with older age, female sex and non-Hispanic black race/ethnicity. The risk of stroke in women appears to decrease as they get older. The higher risk of stroke among non-Hispanic blacks diminished when the data was adjusted for other risk factors such as hypertension and smoking.

Other characteristics that increase the risk of stroke among PLWH include hypertension, high cholesterol and renal dysfunction. Surprisingly, overweight and obesity demonstrated a protective effect against stroke in the study population.

"One proposed mechanism underlying observed sex differences in HIV-associated vascular risk is increased immune activation in women,” Chow and colleagues suggested.

Further research is needed into the relationship between immune activation, menopause and other female-specific stroke risk factors in women with or without HIV.

The study authors also speculated about the apparent protective effect of higher BMI.

“The association between higher BMI and stroke risk could be confounded by overall health status, as individuals with higher BMI may be healthier and have better control of their HIV infection,” they wrote.

In conclusion, Chow and colleagues recommend including PLWH in future studies of stroke risk and prevention to better serve high-risk populations such as women and non-Hispanic blacks.

The study, “Stroke incidence is highest in women and non-Hispanic Blacks living with HIV in the ALLRT cohort,” was published online ahead of print this month in AIDS.