HIV and Strokes

[Mishma]

At some point in time I had mini-strokes which were discovered by MRI in about 2004.


From Medscape Medical News
HIV Patients Have More Ischemic Strokes at Younger Ages
Daniel M. Keller, PhD


http://www.medscape.com/viewarticle/768821?src=nl_topic

August 8, 2012 (Washington, DC) — The pattern of stroke is different in HIV-positive and HIV-negative patients.

On the whole, HIV-infected patients were younger but had a greater likelihood of ischemic stroke, despite having similar traditional risk factors, according to a study presented here at the AIDS 2012: XIX International AIDS Conference.

Lead author Masayuki Nigo, MD, a medical resident at Beth Israel Medical Center and Albert Einstein College of Medicine in New York City, said that these findings suggest that HIV infection somehow promotes stroke.

In the United States, the proportion of stroke patients with HIV rose from 0.09% in 1997 to 0.15% in 2006, and the incidence of ischemic stroke is higher in HIV-positive than in HIV-negative people (5.27 vs 3.75 per 1000 patient-years).

According to Dr. Nigo, many hypotheses have been proposed to explain these differences — accelerated atherosclerosis from dyslipidemia and metabolic syndrome from HIV or highly active antiretroviral therapy (HAART), endothelial dysfunction, a higher prevalence of smoking, hypercoagulability, and the effects of opportunistic infections leading to systemic inflammation. Furthermore, infections of the central nervous system (CNS) (such as tubercular or cryptococcal meningitis) or vasculitis (such as from syphilis or various viruses) can increase the risk for stroke.

To investigate clinical and epidemiologic risk factors for stroke in HIV-infected patients, Dr. Nigo and colleagues performed a retrospective chart review covering the period from January 2005 to June 2011 at their hospital. They compared HIV-positive acute stroke patients with randomly selected acute stroke patients without known HIV infection. Acute stroke was diagnosed on the basis of acute onset of neurologic symptoms and confirmed with imaging. Patients with transient ischemic attacks were excluded.

Of 1679 stroke admissions, 41 of the patients were HIV-positive, with a mean CD4-positive T cell count of 320.9 cells/μL (range, 8 to 1034 cells/μL). Thirty-one of 38 (81.6%) were receiving HAART.

HIV-Positive Patients Younger, With Milder Strokes

The 41 HIV-positive patients were younger than the 101 HIV-negative patients (mean age, 57.2 vs 72.4 years; P = .001). The HIV-positive group had more men than the HIV-negative group (73.1% vs 46.5%; P = .004).

The racial composition of the HIV-positive and HIV-negative groups was also significantly different (P = .001), with fewer whites than blacks with stroke in the HIV-positive group (24.4% vs 74.0%).

Of the traditional risk factors for stroke, only smoking and the presence of atrial fibrillation distinguished the groups on admission (P = .001). Overall, 36.9% of HIV-positive patients and 0.9% of the HIV-negative patients were current smokers. There was a lower prevalence of atrial fibrillation in the HIV-positive than in the HIV-negative group (2.4% vs 16.8%; P = .019).

The groups did not differ significantly in the prevalence of diabetes, hypertension, hyperlipidemia, or history of stroke.

"Interestingly, systolic blood pressure on admission was significantly lower in the HIV-positive group" (140.0 vs 154.5 mm Hg) than in the HIV-negative group, Dr. Nigo reported.

"Importantly, the HDL [high-density lipoprotein] level was significantly lower in the HIV-positive group [40.8 vs 47.8 mg/dL; P = .04]." Other components of the lipid panel did not differ significantly in the 2 groups, and neither did glycated hemoglobin (6.8% in each group).

On admission, National Institutes of Health Stroke Scale scores were lower (indicating milder strokes) in the HIV-positive group than in the HIV-negative group (5.19 vs 9.54; P = .02).

The incidence of ischemic stroke was higher in the HIV-positive group than in the HIV-negative group (95.1% vs 82.2%; P = .044). However, there was no difference between the 2 groups in the type of ischemic stroke (large or small vessel, cardioembolic, or cryptogenic). Although fewer people died in the HIV-positive than in the HIV-negative group, the difference was not significant (4.8% vs 10.9%; P = .24).

"Traditional risk factors like diabetes, hypertension, and hyperlipidemia did not distinguish the HIV-positive and HIV-negative groups, and mortality did not differ between the 2 groups," explained Dr. Nigo. HIV-positive patients were younger than HIV-negative patients; more likely to be male, black, and a current smoker; had lower systolic blood pressure, lower HDL concentration, and milder strokes; had more ischemic strokes; and had less history of atrial fibrillation on admission.

When the analysis was repeated using a subset of the HIV-negative control stroke patients who were age-matched to the HIV-positive patients, results in the 2 groups were similar.

Dr. Nigo concluded that stroke in HIV-positive patients is different from that in HIV-negative patients. The younger age distribution of the HIV-positive patients supports the idea that HIV promotes stroke in some way. Evaluating the contribution to stroke risk of low HDL levels, smoking, and the metabolic effects of HIV and HAART (e.g., insulin resistance, metabolic syndrome) will require longitudinal studies.

At this point, Dr. Nigo recommends that given the higher rate of smoking in the HIV-positive group, smoking cessation could be an important factor in lowering stroke risk. He also recommends that clinicians determine the HIV status of all stroke patients, especially the younger ones.

He noted that the study is limited by its retrospective nature, the small sample size, the lack of adjustment for multiple comparisons, and missing data on viral loads.

Session moderator Grace McComsey, MD, professor of medicine and pediatrics at Case Western Reserve University and division chief of pediatric infectious diseases and rheumatology at University Hospitals of Cleveland in Ohio, called the study "very interesting."

"It's really telling us we should look at stroke more often. Several other studies have shown it to be more common [in HIV-infected patients]. It was interesting and surprising to me that the intensity of the stroke...was milder in HIV-positive than in HIV-negative patients, but that could be because the negative patients have more underlying CNS diseases. They're older, so they may have more pathology."

She cautioned that the retrospective nature of the study should be kept in mind; "there are multiple confounders that were not accounted for."

The study had no commercial funding. Dr. Nigo has disclosed no relevant financial relationships. Dr. McComsey reports consulting for Bristol-Myers Squibb, GSK, and Pfizer.

AIDS 2012: XIX International AIDS Conference: Abstract THAB0204. Presented July 26, 2012.