Role of metabolic syndrome components in human immunodeficiency virus-associated stroke

Stroke and HIV-associated neurological complications: A retrospective nationwide study

There is an increased risk of stroke and other neurological complications in human immunodeficiency virus (HIV) infected patients with no large population-based studies in the literature. We aim to evaluate the prevalence of stroke, HIV-associated neurological complications, and identify risk factors associated with poor outcomes of stroke among HIV admissions in the United States. In the nationwide inpatient sample with adult HIV hospitalizations, patients with primary cerebrovascular disease (CeVDs) and HIV-associated neurological complications were identified by ICD-9-CM codes. We performed a retrospective study with weighted analysis to evaluate the prevalence of stroke and neurological complications and outcomes of stroke among HIV patients. We included 1,559,351 HIV admissions from 2003 to 2014, of which 22470 (1.4%) patients had CeVDs (transient ischemic attack [TIA]: 3240 [0.2%], acute ischemic stroke [AIS]: 14895 [0.93%], and hemorrhagic stroke [HS]: 4334 [0.27%]), 7781 (0.49%) had neurosyphilis, 29,925 (1.87%) meningitis, 39,190 (2.45%) cytomegalovirus encephalitis, 4699 (0.29%) toxoplasmosis, 9964 (0.62%) progressive multifocal leukoencephalopathy, and 142,910 (8.94%) epilepsy. There is increased overall prevalence trend for CeVDs (TIA: 0.17%-0.24%; AIS: 0.62%-1.29%; HS: 0.26%-0.31%; pTrend < .0001) from 2003 to 2014. Among HIV admissions, variables associated with AIS were neurosyphilis (odds ratio: 4.38; 95% confidence interval: 3.21-5.97), meningitis (4.87 [4.10-5.79]), and central nervous system tuberculosis (6.72 [3.85-11.71]). Toxoplasmosis [4.27 [2.34-7.76]), meningitis (2.91 [2.09-4.06)], and cytomegalovirus encephalitis (1.62 [1.11-2.37]) were associated with higher odds of HS compared to patients without HS. There was an increasing trend of CeVDs over time among HIV hospitalizations. HIV-associated neurological complications were associated with the risk of stroke, together with increased mortality, morbidity, disability, and discharge to long-term care facilities. Further research would clarify stroke risk factors in HIV patients to mitigate adverse outcomes.

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.

Cerebrovascular Disease in Children Perinatally Infected With Human Immunodeficiency Virus in Zambia

BACKGROUND

High rates of cerebrovascular disease (CVD) have previously been described in pediatric human immunodeficiency virus (HIV). However, little is known about pediatric CVD in the era of antiretroviral therapy or about the contribution of CVD to HIV-associated neurocognitive disorders.

METHODS

We completed a neuroimaging substudy of the HIV-Associated Neurocognitive Disorders in Zambia study, a prospective cohort study of neurocognitive complications of pediatric HIV. Brain magnetic resonance imaging (1.5 T) was acquired for 34 HIV+ children on antiretroviral therapy and 17 HIV-exposed uninfected children (aged eight to 17 years). Demographics, medical history, neurological examination, and neuropsychologic testing results were collected. Two neuroradiologists, unaware of HIV status and clinical course, read the scans.

RESULTS

CVD was identified in seven of 34 children with HIV (HIV+ CVD+) and no HIV-exposed uninfected children (21% vs 0%, P = 0.05). Three participants had white matter changes suggestive of small vessel disease, four had infarcts, and two had evidence of intracranial artery stenosis. Age of antiretroviral therapy initiation and exposure to protease inhibitors or efavirenz was not significantly different between children with and without CVD. HIV+ CVD+ children had significantly worse scores on a summary measure of cognition than the HIV+ CVD- group (NPZ8 score -0.57 vs 0.33, P = 0.04).

CONCLUSIONS

This study demonstrates high rates of CVD in children with HIV despite antiretroviral therapy, and worse cognitive performance in children with CVD. Longitudinal studies are necessary to determine the mechanisms and incidence of new-onset CVD in children with HIV.

HIV infection does not influence stroke outcomes in HIV-infected patients: A prospective study

BACKGROUND

Human immunodeficiency virus (HIV) infection, opportunistic infections and antiretroviral therapy contribute to the pathogenesis of stroke, yet, little is known about the influence of HIV infection on outcome in stroke patients. The aim of this study was to compare the outcome of stroke in HIV-infected patients with that of HIV-negative patients at the Douala General Hospital (DGH).

PATIENTS AND METHODS

A prospective cohort study was carried out at the Neurology unit and the Intensive Care Unit of the DGH from January 2010 to December 2015. All patients aged 15 years and above, admitted for stroke confirmed by brain imaging were included. HIV testing was systematically prescribed for all stroke patients. HIV-infected patients were then compared with HIV-uninfected patients. Quantitative variables were expressed as means while qualitative variables were expressed as frequencies, and were compared with the Chi² test or the Fisher test and the Student test respectively. Stroke outcome was evaluated by the mortality, in-hospital stay and functional outcome at 6 months post-stroke. Kaplan-Meyer method was used to determine survival.

RESULTS

Forty of the 608 patients with stroke were HIV-positive, giving an in-hospital HIV prevalence of 6.6%. Mean age of the HIV-infected stroke patients was 51.3±10.4 years as against 59.6±13.53 in the HIV-uninfected group (P=0.001). The proportion of dyslipidemia in HIV-infected stroke patients with was greater than that in HIV-uninfected stroke patients (57.5% vs 8.9%, P<0.001). The most common type of stroke was ischemic in two-thirds of the patients in both groups. HIV-infected stroke patients had a mean hospital stay longer than that of HIV-uninfected patients (10.3±8.1 days vs 8.1±6.3 days, P=0.042). Post-stroke infections were more frequent in HIV-infected patients (17.5% vs 6.9%, P=0.014). The cumulative mortality rates at 6 months were 37.5% and 34.5% for the HIV-infected and the HIV-uninfected groups respectively (P=0.471). The functional outcome was similar in both groups at the 6^th month post-stroke (Rankin score>2: 38.5%vs 38.8%, P=0.973). There was no difference in survival between the two groups.

CONCLUSION

HIV infection does not affect in-hospital mortality and functional outcome in stroke patients a part the length of hospital stay.

Stroke in HIV

Stroke is a heterogeneous disease in persons living with human immunodeficiency virus (HIV). HIV is thought to increase the risk of stroke through both HIV-related and traditional stroke risk factors, which vary with respect to the patient's age and clinical characteristics. Numerous studies show that detectable viremia and immunosuppression increase the risk of stroke across all ages, whereas traditional risk factors are more common in the aging population with HIV. As persons living with HIV age and acquire traditional stroke risk factors, the prevalence of stroke will likely continue to increase. Large- and small-vessel disease are the most common causes of stroke, although it is important to evaluate for infectious etiology as well. Research regarding the management of stroke in patients with HIV is scant, and recommendations often parallel those for the general population. Treatment of HIV and effective reduction of traditional stroke risk factors is important to reduce the risk of stroke in persons living with HIV. Future research will help elucidate the pathophysiology of HIV and stroke risk, investigate sex differences in stroke risk, and evaluate the safety and benefits of standard stroke preventative measures and HIV-specific interventions in this population.

Prevalence of and risk factors for gout in HIV-positive adults: A case-control study

Gout is the most common inflammatory arthritis worldwide. Its principal risk factor is hyperuricaemia. While gout has been described in HIV patients and numerous more outdated anti-retroviral therapies (ARTs) have been implicated, there have been few recent studies. Our case-control study investigated the prevalence of and risk factors for gout in an established HIV cohort. Cases were identified from database searches using key search terms, with two age- and gender-matched controls. These were compared for demographic factors, co-morbidities, HIV factors and ART exposure. Forty-five cases with gout were identified (point prevalence 2.2%). All were male and were more likely than controls to be of black African origin. Hypertension was associated with an almost five-fold increased gout risk (OR 4.8, 95% CI 1.8-12.4). No individual drug or ART class was associated with gout in this study but exposure to non-nucleoside reverse transcriptase inhibitors had a significantly protective effect against the risk of gout (OR 0.3, 95% CI 0.1-0.9). Our data suggest that gout is common in HIV patients and that the traditional risk factors, especially hypertension, play a key role. Gout and hyperuricaemia should be regarded as a biomarker of cardiovascular disease in HIV patients as they are in the general population.

Prevalence and incidence of hypertension in the global HIV-infected population: a systematic review and meta-analysis protocol

INTRODUCTION

Hypertension, representing one of the most frequent cardiovascular risk factors, is thought to increase in individuals living with HIV as well as in general population, but summarised global data on the topic are scarce. We conduct this systematic review and meta-analysis to assess the prevalence/incidence of hypertension in the global HIV-infected population.

METHODS AND ANALYSIS

This review will include observational studies conducted among HIV-infected people, which reported prevalence/incidence of hypertension or enough data for its appraisal. We will consider published and unpublished studies from 1 January 2007 to 31 May 2017. Relevant records will be searched using PubMed/Medline, Global Index Medicus, Web of Science and EMBASE. Reference lists of eligible papers and relevant review articles will be screened. Two investigators will independently screen, select studies and extract data, with discrepancies resolved by consensus or by arbitration of a third investigator. Methodological quality of the included studies will be assessed using the scale developed by Hoy and colleagues. Funnel plots and Egger's test will be used to determine publication bias. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate. To keep the effect of studies with extremely small or extremely large estimates on the overall estimate to a minimum, the variance of the study-specific prevalence/incidence will be stabilised with the Freeman-Tukey single arcsine transformation. The heterogeneity will be evaluated by the χ² test on Cochrane's Q statistic. Results will be presented by geographic region, income and antiretroviral therapy status.

ETHICS AND DISSEMINATION

This study is based on published data; therefore, ethical approval is not a requirement. The final report of this study in the form of a scientific paper will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

CRD42016051684.

[Incidence of strokes in HIV-positive patients treated with long term antiretroviral treatment]

INTRODUCTION

With the introduction of triple therapy regimen in 1996, the morbidity and mortality associated with HIV infection decreased significantly. Concomitantly with this clinical success, several metabolic changes including diabetes, arterial hypertension, dyslipidemia and lipodystrophy were observed, being associated with the risk of stroke. This study aims to determine the incidence of strokes in HIV-positive patients treated with long term antiretroviral treatment.

METHODS

This was a retrospective cohort study of HIV-positive adult patients receiving long term antiretroviral treatment for at least 12 months. It was conducted at the Approved Treatment Centres of Douala General Hospital (HGD); data collection spanned a 10-year period from May 2001 to April 2010. Patients were treated according to Cameroon national treatment guidelines. The Kaplan-Meyer method was used to determine the time of stroke onset. The Khi-2 test was used to investigate the association between two qualitative variables. The statistical significance level was set at 0.05.

RESULTS

407 patients were included in the study, 62.4% were female, the average age was 40.1 ± 9.9 years. The incidence of strokes was 1.7% over 72 months follow up with no significant difference between women and men (P = 0.76). The incidence rate was calculated to be 0.3 per 100 person years. 85.7% of cases had an ischemic stroke. The mean time from stroke onset was 33.4 months. Factors associated with stroke occurrence were: patients who underwent treatment at WHO Clinical Stage III and IV and with CD4 count> 100/mm3at the start of antiretroviral therapy.

CONCLUSION

The incidence of stroke in HIV-positive patients treated with long term antiretroviral therapy is similar to that previously reported but these strokes occur at an early age and justify increased clinical monitoring. A prospective study involving a control population is needed.

A Meta-Analysis of the Metabolic Syndrome Prevalence in the Global HIV-Infected Population

BACKGROUND

Cardio-metabolic risk factors are of increasing concern in HIV-infected individuals, particularly with the advent of antiretroviral therapy (ART) and the subsequent rise in longevity. However, the prevalence of cardio-metabolic abnormalities in this population and the differential contribution, if any, of HIV specific factors to their distribution, are poorly understood. Therefore, we conducted a systematic review and meta-analysis to estimate the global prevalence of metabolic syndrome (MS) in HIV-infected populations, its variation by the different diagnostic criteria, severity of HIV infection, ART used and other major predictive characteristics.

METHODS

We performed a comprehensive search on major databases for original research articles published between 1998 and 2015. The pooled overall prevalence as well as by specific groups and subgroups were computed using random effects models.

RESULTS

A total of 65 studies across five continents comprising 55094 HIV-infected participants aged 17-73 years (median age 41 years) were included in the final meta-analysis. The overall prevalence of MS according to the following criteria were: ATPIII-2001:16.7% (95%CI: 14.6-18.8), IDF-2005: 18% (95%CI: 14.0-22.4), ATPIII-2004-2005: 24.6% (95%CI: 20.6-28.8), Modified ATPIII-2005: 27.9% (95%CI: 6.7-56.5), JIS-2009: 29.6% (95%CI: 22.9-36.8), and EGIR: 31.3% (95%CI: 26.8-36.0). By some MS criteria, the prevalence was significantly higher in women than in men (IDF-2005: 23.2% vs. 13.4, p = 0.030), in ART compared to non-ART users (ATPIII-2001: 18.4% vs. 11.8%, p = 0.001), and varied significantly by participant age, duration of HIV diagnosis, severity of infection, non-nucleoside reverse transcriptase inhibitors (NNRTIs) use and date of study publication. Across criteria, there were significant differences in MS prevalence by sub-groups such as in men, the Americas, older publications, regional studies, younger adults, smokers, ART-naïve participants, NNRTIs users, participants with shorter duration of diagnosed infection and across the spectrum of HIV severity. Substantial heterogeneities across and within criteria were not fully explained by major study characteristics, while evidence of publication bias was marginal.

CONCLUSIONS

The similar range of MS prevalence in the HIV-infected and general populations highlights the common drivers of this condition. Thus, cardio-metabolic assessments need to be routinely included in the holistic management of the HIV-infected individual. Management strategies recommended for MS in the general population will likely provide similar benefits in the HIV-infected.

HCV, but not HIV, is a risk factor for cerebral small vessel disease

OBJECTIVES

With the aging of HIV populations, vascular contributions to neuropathogenesis are increasingly important. Indirect analyses of cerebral small vessel disease have been performed, but there have been no direct studies of human brain to elucidate risk factors for arteriolar sclerosis.

METHODS

Mean arteriolar wall thickness (sclerotic index, SI) was measured in the deep cerebral white matter of 126 brains (96 HIV+, 30 HIV-). Correlations with SI were performed for age, sex, race, hypertension, hyperlipidemia, diabetes, obesity, cirrhosis, hepatitis C virus (HCV) infection, herpes infection, HIV infection, HIV risk, cocaine use, CD4 count, plasma HIV load, and combination antiretroviral therapy (cART) at the time of death.

RESULTS

Age, hypertension, race, HCV, and cirrhosis were associated with SI; of the HIV variables, only cART at death was associated with SI. To address colinearity, partial correlations were run with HCV and cirrhosis, hypertension and race, and hypertension and age. With HCV controlled, cirrhosis lost significance; with hypertension controlled, age lost significance. For the entire sample, HCV, African American race, and hypertension accounted for 15% of SI variance in multivariate analysis. Each was independently associated with SI, and HCV had the largest effect. For the HIV sample, inclusion of cART in the model increased R (2) to 0.205, with only HCV, hypertension, and cART remaining significant or trend level.

CONCLUSIONS

This tissue-based analysis of cerebral arteriolar disease demonstrates that HCV constitutes an independent risk, in addition to African American race, hypertension, and cART. Further study is needed to understand what aspects of HCV and cART contribute to cerebrovascular neuropathogenesis.

Predictors of CNS injury as measured by proton magnetic resonance spectroscopy in the setting of chronic HIV infection and CART

The reasons for persistent brain dysfunction in chronically HIV-infected persons on stable combined antiretroviral therapies (CART) remain unclear. Host and viral factors along with their interactions were examined in 260 HIV-infected subjects who underwent magnetic resonance spectroscopy (MRS). Metabolite concentrations (NAA/Cr, Cho/Cr, MI/Cr, and Glx/Cr) were measured in the basal ganglia, the frontal white matter, and gray matter, and the best predictive models were selected using a bootstrap-enhanced Akaike information criterion (AIC). Depending on the metabolite and brain region, age, race, HIV RNA concentration, ADC stage, duration of HIV infection, nadir CD4, and/or their interactions were predictive of metabolite concentrations, particularly the basal ganglia NAA/Cr and the mid-frontal NAA/Cr and Glx/Cr, whereas current CD4 and the CPE index rarely or did not predict these changes. These results show for the first time that host and viral factors related to both current and past HIV status contribute to persisting cerebral metabolite abnormalities and provide a framework for further understanding neurological injury in the setting of chronic and stable disease.

Comparison of ischemic stroke incidence in HIV-infected and non-HIV-infected patients in a US health care system

BACKGROUND

Cardiovascular disease is increased among HIV-infected patients, but little is known regarding ischemic stroke rates. We sought to compare stroke rates and determine stroke risk factors in HIV-infected versus non-HIV-infected patients.

METHODS

An HIV cohort and matched non-HIV comparator cohort seen between 1996 and 2009 were identified from a Boston health care system. The primary endpoint was ischemic stroke, defined using International Classification of Diseases (ICD) codes. Unadjusted stroke incidence rates were calculated. Cox proportional hazards modeling was used to determine adjusted hazard ratios (HRs).

RESULTS

The incidence rate of ischemic stroke was 5.27 per 1000 person-years in HIV-infected compared with 3.75 in non-HIV-infected patients, with an unadjusted HR of 1.40 [95% confidence interval (CI): 1.17 to 1.69, P < 0.001]. HIV remained an independent predictor of stroke after controlling for demographics and stroke risk factors (HR: 1.21, 95% CI: 1.01 to 1.46, P = 0.043). The relative increase in stroke rates (HIV vs. non-HIV) was significantly higher in younger HIV patients (incidence rate ratio: 4.42, 95% CI: 1.56 to 11.09, age 18-29; 2.96, 1.69-4.96, age: 30-39; 1.53, 1.06-2.17, age: 40-49), and in women [HR: 2.16 (95% CI: 1.53 to 3.04) for women vs. HR: 1.18 (95% CI: 0.95 to 1.47) for men]. Among HIV patients, increased HIV RNA (HR: 1.10, 95% CI: 1.04 to 1.17, P = 0.001) was associated with an increased risk of stroke.

CONCLUSIONS

Stroke rates were increased among HIV-infected patients, independent of common stroke risk factors, particularly among young patients and women.

Persistence of HIV-associated cognitive impairment, inflammation, and neuronal injury in era of highly active antiretroviral treatment

OBJECTIVE

To determine whether cognitive impairment and brain injury as measured by proton magnetic resonance spectroscopy (MRS) persist in the setting of HAART.

DESIGN

This study is an observational cohort study.

METHODS

MRS was performed in 268 patients: HIV-negative controls (N = 28), HIV-positive neuroasymptomatic individuals (N = 124), and individuals with AIDS dementia complex (ADC; N = 50) on stable antiretroviral therapy (ART) with a mean duration of infection of 12 years and CD4 cell count of 309 cells/μl. Four metabolites were measured over creatine: N-acetyl aspartate (NAA), marker of neuronal integrity; choline (Cho), myoinositol, markers of inflammation, and glutamate and glutamine (Glx) in the basal ganglia, frontal white matter (FWM), and mid-frontal cortex. Analyses included analysis of variance, analysis of covariance, linear, and nonparametric regression models.

RESULTS

Cognitive impairment was found in 48% of HIV-infected individuals. Both HIV-positive groups showed significant increases in myoinositol/creatine or Cho/creatine in all brain regions when compared to controls; a significant decrease in Glx/creatine in the FWM was observed in the neuroasymptomatic group; and only individuals with ADC showed a significant reduction in NAA/creatine, although a significant trend for decreasing NAA/creatine in the basal ganglia was found across the groups. Effects related to aging and duration of infection, but not central nervous system penetration effectiveness were observed.

CONCLUSION

Brain inflammatory changes remain ubiquitous among HIV-infected individuals, whereas neuronal injury occurs predominantly in those with cognitive impairment. Together these findings indicate that despite the widespread use of HAART, HIV-associated cognitive impairment and brain injury persist in the setting of chronic and stable disease.

Increasing incidence of ischemic stroke in patients with HIV infection

BACKGROUND

Large-scale epidemiologic data on stroke in HIV-infected persons are scarce, especially in an era of combination antiretroviral therapies, which have prolonged patient survival, but may boost stroke risk. We assessed trends in the proportion of HIV infection among patients with stroke in the United States.

METHODS

Data were obtained from all states within the United States that contributed to the Nationwide Inpatient Sample. All patients admitted to hospitals between 1997 and 2006 with a primary discharge diagnosis of stroke (identified by the International Classification of Diseases, Ninth Revision procedure codes) were included. Time trends in the proportion of these patients with HIV diagnosis were computed, and independent predictors of comorbid HIV diagnosis evaluated using multivariable logistic regression.

RESULTS

Of all (ischemic and hemorrhagic) stroke hospitalizations, patients with comorbid HIV infection constituted 0.09% in 1997 vs 0.15% in 2006 (p < 0.0001). Actual numbers of overall US stroke hospitalizations lessened 7% (998,739 to 926,997), while actual numbers of stroke hospitalizations with coexisting HIV infection rose 60% (888 to 1,425). Patients with comorbid HIV infection comprised 0.08% of ischemic strokes in 1997 vs 0.18% in 2006 (p < 0.0001), but their proportion of hemorrhagic strokes did not significantly change. Factors independently associated with higher odds of comorbid HIV diagnosis were Medicaid insurance, urban hospital type, dementia, liver disease, renal disease, and cancer.

CONCLUSION

Over the last decade in the United States, there has been a substantial and significant rise in patients hospitalized for stroke with coexisting HIV infection. This has important public health and socioeconomic consequences.