HIV Viremia and Risk of Stroke Among People Living with HIV Who Are Using Antiretroviral Therapy.

BACKGROUND: Rates of stroke are higher in people living with HIV compared with age-matched uninfected individuals. Causes of elevated stroke risk, including the role of viremia, are poorly defined. METHODS: Between 1 January 2006 and 31 December 2014, we identified incident strokes among people living with HIV on antiretroviral therapy at five sites across the United States. We considered three parameterizations of viral load (VL) including (1) baseline (most recent VL before study entry), (2) time-updated, and (3) cumulative VL (copy-days/mL of virus). We used Cox proportional hazards models to estimate hazard ratios (HRs) for stroke risk comparing the 75th percentile ("high VL") to the 25th percentile ("low VL") of baseline and time-updated VL. We used marginal structural Cox models, with most models adjusted for traditional stroke risk factors, to estimate HRs for stroke associated with cumulative VL. RESULTS: Among 15,974 people living with HIV, 139 experienced a stroke (113 ischemic; 18 hemorrhagic; eight were unknown type) over a median follow-up of 4.2 years. Median baseline VL was 38 copies/mL (interquartile interval: 24, 3,420). High baseline VL was associated with increased risk of both ischemic (HR: 1.3; 95% CI = 0.96-1.7) and hemorrhagic stroke (HR: 3.1; 95% CI = 1.6-5.9). In time-updated models, high VL was also associated with an increased risk of any stroke (HR: 1.8; 95% CI = 1.4-2.3). We observed no association between cumulative VL and stroke risk. CONCLUSIONS: Our findings are consistent with the hypothesis that elevated HIV VL may increase stroke risk, regardless of previous VL levels.

Charles Bonnet Syndrome in a Patient With Acute Glaucoma Following Carotid Endarterectomy.

Acute neovascular glaucoma is an extremely rare complication following carotid artery revascularization that can lead to permanent vision loss. We describe an unusual case of acute glaucoma following carotid endarterectomy presenting with mechanical pupillary dilation and vivid visual hallucinations consistent with the Charles Bonnet Syndrome. This case highlights the importance of screening patients complaining of vision loss or eye pain for neovascular eye changes prior to carotid revascularization. These patients' eye health should be closely monitored peri-operatively.

Elevated Plasma von Willebrand Factor Levels Are Associated With Subsequent Ischemic Stroke in Persons With Treated HIV Infection.

Background: We assessed whether key biomarkers of endothelial activation and hemostasis/thrombosis were elevated in individuals receiving effective antiretroviral therapy (ART) in the year before ischemic stroke. Methods: We conducted a case-control study nested in the CFAR Network of Integrated Clinical Systems cohort, comparing 42 adjudicated cases with ischemic stroke with 83 controls matched for ART regimen. Angiopoietin-1, angiopoietin-2, C-reactive protein, interleukin-6, plasminogen activation inhibitor-1, P-selectin, serum amyloid-A, soluble CD14, ICAM-1, VCAM-1, apolipoprotein A1, ADAMTS13, and von Willebrand factor (VWF) were measured in stored plasma collected before the stroke event. We used conditional logistic regression to identify associations with ischemic stroke, with and without adjustment for Atherosclerotic Cardiovascular Disease (ASCVD) and Veterans Aging Cohort Study (VACS) scores. Results: After adjustment for age and sex, higher plasma viral load and higher angiopoeitin-2, soluble CD14, and VWF were associated with increased odds of ischemic stroke; higher nadir CD4 count was associated with decreased odds of ischemic stroke. VWF remained associated with subsequent ischemic stroke after adjustment for ASCVD score (adjusted odds, 1.74; 95% CI, 1.01-2.98 per log2 increment). In a separate model adjusting for VACS score, only VWF (adjusted odds, 1.80; 95% CI, 1.04-3.12 per log2 increment) was associated with subsequent ischemic stroke. In a sensitivity analysis excluding participants with viral load ≥400 copies/mL, associations between VWF and ischemic stroke were attenuated, with risk estimates ranging from 1.59 to 1.64 per log2 increment. Conclusions: Endothelial activation and related release and attachment of VWF may play an important role in ischemic stroke among persons with treated HIV infection.

Types of Stroke Among People Living With HIV in the United States.

BACKGROUND: Most studies of stroke in people living with HIV (PLWH) do not use verified stroke diagnoses, are small, and/or do not differentiate stroke types and subtypes. SETTING: CNICS, a U.S. multisite clinical cohort of PLWH in care. METHODS: We implemented a centralized adjudication stroke protocol to identify stroke type, subtype, and precipitating conditions identified as direct causes including infection and illicit drug use in a large diverse HIV cohort. RESULTS: Among 26,514 PLWH, there were 401 strokes, 75% of which were ischemic. Precipitating factors such as sepsis or same-day cocaine use were identified in 40% of ischemic strokes. Those with precipitating factors were younger, had more severe HIV disease, and fewer traditional stroke risk factors such as diabetes and hypertension. Ischemic stroke subtypes included cardioembolic (20%), large vessel atherosclerosis (13%), and small vessel (24%) ischemic strokes. Individuals with small vessel strokes were older, were more likely to have a higher current CD4 cell count than those with cardioembolic strokes and had the highest mean blood pressure of the ischemic stroke subtypes. CONCLUSION: Ischemic stroke, particularly small vessel and cardioembolic subtypes, were the most common strokes among PLWH. Traditional and HIV-related risk factors differed by stroke type/subtype. Precipitating factors including infections and drug use were common. These results suggest that there may be different biological phenomena occurring among PLWH and that understanding HIV-related and traditional risk factors and in particular precipitating factors for each type/subtype may be key to understanding, and therefore preventing, strokes among PLWH.

Association Between Bilirubin, Atazanavir, and Cardiovascular Disease Events Among People Living With HIV Across the United States.

OBJECTIVE: Bilirubin is an antioxidant that may suppress lipid oxidation. Elevated bilirubin is associated with decreased cardiovascular events in HIV-uninfected populations. We examined these associations in people living with HIV (PLWH). METHODS: Potential myocardial infarctions (MIs) and strokes were centrally adjudicated. We examined MI types: type 1 MI (T1MI) from atherosclerotic plaque instability and type 2 MI (T2MI) in the setting of oxygen demand/supply mismatch such as sepsis. We used multivariable Cox regression analyses to determine associations between total bilirubin levels and outcomes adjusting for traditional and HIV-specific risk factors. To minimize confounding by hepatobiliary disease, we conducted analyses limited to bilirubin values <2.1 mg/dL; among those with fibrosis-4 values <3.25; and among everyone. We repeated analyses stratified by hepatitis C status and time-updated atazanavir use. RESULTS: Among 25,816 PLWH, there were 392 T1MI and 356 T2MI during follow-up. Adjusted hazard ratios for the association of higher bilirubin levels with T1MI were not significant. Higher bilirubin levels were associated with T2MI. By contrast, among PLWH on atazanavir, higher bilirubin levels were associated with fewer T2MI (hazard ratio 0.56:0.33-1.00). Higher bilirubin levels among those on atazanavir were associated with fewer T1MI combined with ischemic stroke. LIMITATIONS: Analyses were conducted with total rather than unconjugated bilirubin. CONCLUSIONS: Among PLWH, higher bilirubin levels were associated with T2MI among some subgroups. However, among those on atazanavir, there was a protective association between bilirubin and T2MI. These findings demonstrate different associations between outcomes and elevated bilirubin due to diverse causes and the importance of distinguishing MI types.