Human immunodeficiency virus infection and stroke in young patients

Global and Regional Estimate of HIV-Associated Stroke Burden: A Meta-Analysis and Population Attributable Modeling Study

BACKGROUND

This study aimed to determine the correlation between human-immunodeficiency-virus (HIV) infection and stroke, as well as to estimate the global, regional, and national burden of HIV-associated stroke.

METHODS

A registered meta-analysis was performed by searching PubMed, Embase, and Web of Science for relevant literature up to October 31, 2022. The pooled relative risk of stroke in HIV-infected people was calculated using a random-effects model. HIV prevalence and disability-adjusted life years (DALYs) datasets were obtained from the Joint United Nations Program on HIV and AIDS, and the Global Health Data Exchange, respectively. The population attributable fraction was estimated and delivered to calculate the HIV-associated DALYs of stroke from 1990 to 2019, at the global, regional, and national levels. Pearson correlation analysis were conducted to assess the correlation between the age-standardized rate or estimated annual percentage changes and the sociodemographic index.

RESULTS

Out of 10 080 identified studies, 11 were included in this meta-analysis. Compared with individuals without HIV-infection, the pooled relative risk of stroke in HIV-infected individuals was 1.40 (95% CI, 1.18-1.65). From 1990 to 2019, the global population attributable fraction of HIV-associated stroke increased almost 3-fold, while the HIV-associated DALYs increased from 18 595 (95% CI, 7485-31 196) in 1990 to 60 684 (95% CI, 24 281-101 894) in 2019. Meanwhile, HIV-associated DALYs varied by region, with Eastern and Southern Africa having the highest value of 126 160 in 2019. Moreover, countries with middle social development index were shouldering the highest increase trend of the HIV-associated DALYs age-standardized rates.

CONCLUSIONS

HIV-infected individuals face a significantly higher risk of stroke, and the global burden of HIV-associated stroke has increased over the past 3 decades, showing regional variations. Eastern and Southern Africa bear the highest burden, while Eastern Europe and Central Asia have seen significant growth. Health care providers, researchers, and decision-makers should give increased attention to stroke prevention and management in HIV-endemic areas.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: CRD42022367450.

Analysis of the demographic characteristics and clinical profile of acute ischemic strokes admitted to the emergency centre in the Somalia population

Background

Stroke is a leading cause of death and chronic disability worldwide. In Sub-Saharan Africa (SSA), which includes Somalia, stroke represents a significant part of the chronic disease burden. However, there is relatively little data on risk factors, demographics, and clinical profiles. This study aimed to define the etiological, demographic characteristics, classification of stroke and functional status of patients with acute ischemic stroke (AIS) admitted to the emergency centre, and to create projections to evaluate the incidence and genetic aspects of stroke.

Methods

The study population consisted of patients who applied to the emergency centre between 1 May 2017 and 1 May 2021 and were diagnosed with acute ischemic stroke (AIS). Patient demographics, season of onset, risk factors, laboratory data, imaging results, infarct location, AIS subtype and treatment outcomes were collected, and compared.

Results

A total of 3,968 patients diagnosed with ischemia stroke were included in the study. The mean age was 51.12 ± 16.43 years, and we reported male predominance (65.7%). While hypertension, hyperlipidaemia, Diabetes mellitus (DM) were more frequent among the risk factors, smoking history and alcohol consumption history were very low. HIV-infected ischemic stroke was detected at a high rate (20.9%) and was common in a relatively young age group (31.8 ± 14.3). Large-artery atherosclerosis (LAA) subtype was detected with a high rate of 67.7%. The most common clot localization was in Supratentorial location (74.3%), and according to OSCP classification, partial anterior circulation infarcts (PACI) subtype (56.3%) was the most common. And these results were again different from other studies.

Discussion

While the incidence of stroke and especially HIV-associated youthful ischemic stroke continues to increase rapidly in developing countries such as Somalia, with the addition of inadequate primary health care services, stroke has become a major public health problem in African countries regarding its costs at social, psychological, and economic levels.

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.

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.

HIV Associated Risk Factors for Ischemic Stroke and Future Perspectives

Although retroviral therapy (ART) has changed the HIV infection from a fatal event to a chronic disease, treated HIV patients demonstrate high prevalence of HIV associated comorbidities including cardio/cerebrovascular diseases. The incidence of stroke in HIV infected subjects is three times higher than that of uninfected controls. Several clinical and postmortem studies have documented the higher incidence of ischemic stroke in HIV infected patients. The etiology of stroke in HIV infected patients remains unknown; however, several factors such as coagulopathies, opportunistic infections, vascular abnormalities, atherosclerosis and diabetes can contribute to the pathogenesis of stroke. In addition, chronic administration of ART contributes to the increased risk of stroke in HIV infected patients. Concurrently, experimental studies in murine model of ischemic stroke demonstrated that HIV infection worsens stroke outcome, increases blood brain barrier permeability and increases neuroinflammation. Additionally, residual HIV viral proteins, such as Trans-Activator of Transcription, glycoprotein 120 and Negative regulatory factor, contribute to the pathogenesis. This review presents comprehensive information detailing the risk factors contributing to ischemic stroke in HIV infected patients. It also outlines experimental evidence demonstrating the impact of HIV infection on stroke outcomes, in addition to possible novel therapeutic approaches to improve these outcomes.

Neurological disorders in HIV in Africa: a review

BACKGROUND

Neurological disorders in HIV infection are a common cause of morbidity and mortality. The aim of this paper is to provide a narrative overview of up to date information concerning neurological disorders affecting HIV infected persons in Africa.

METHODS

Seminal research concerning neurological disorders among HIV-infected adults in sub-Saharan Africa from prior to 2000 was combined with an in-depth search of PubMed to identify literature published from 2000 to 2017. The following Mesh terms were used. "Nervous System Diseases" "HIV Infections" and "Africa South of the Sahara" and "Seizures" or "Spinal Cord Diseases" or "Peripheral Nervous System Diseases" or "AIDS Dementia Complex" or "Opportunistic Infections" or "Immune Reconstitution Inflammatory Syndrome" or "Stroke". Only those articles written in English were used. A total of 352 articles were identified, selected and reviewed and 180 were included in the study. These included case series, observational studies, interventional studies, guidelines and reviews with metanalyses. The author also included 15 publications on the subject covering the earlier phase of the HIV epidemic in Africa from 1987 to 1999 making a total of 195 references in the study. This was combined with extensive personal experience diagnosing and treating these neurological disorders.

RESULTS

Neurological disorders were common, typically occurring in WHO stages III/IV. These were in three main categories: those arising from opportunistic processes mostly infections, direct HIV infection and autoimmunity. The most common were those arising from direct HIV infection occurring in >50%. These included HIV-associated neurocognitive dysfunction (HAND), neuropathy and myelopathy. Opportunistic infections occurred in >20% and frequently had a 6-9-month mortality rate of 60-70%. The main causes were cryptococcus, tuberculosis, toxoplasmosis and acute bacterial meningitis. Concurrent systemic tuberculosis occurred in almost 50%.

CONCLUSION

Neurological disorders are common in HIV in Africa and the main CNS opportunistic infections result in high mortality rates. Strategies aimed at reducing their high burden, morbidity and mortality include early HIV diagnosis and anti-retroviral therapy (ART), screening and chemoprophylaxis of main opportunistic infections, improved clinical diagnosis and management and programme strengthening.

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.

Global Burden of Atherosclerotic Cardiovascular Disease in People Living With HIV: Systematic Review and Meta-Analysis

BACKGROUND

With advances in antiretroviral therapy, most deaths in people with HIV are now attributable to noncommunicable illnesses, especially cardiovascular disease. We determine the association between HIV and cardiovascular disease, and estimate the national, regional, and global burden of cardiovascular disease attributable to HIV.

METHODS

We conducted a systematic review across 5 databases from inception to August 2016 for longitudinal studies of cardiovascular disease in HIV infection. A random-effects meta-analysis across 80 studies was used to derive the pooled rate and risk of cardiovascular disease in people living with HIV. We then estimated the temporal changes in the population-attributable fraction and disability-adjusted life-years (DALYs) from HIV-associated cardiovascular disease from 1990 to 2015 at a regional and global level. National cardiovascular DALYs associated with HIV for 2015 were derived for 154 of the 193 United Nations member states. The main outcome measure was the pooled estimate of the rate and risk of cardiovascular disease in people living with HIV and the national, regional, and global estimates of DALYs from cardiovascular disease associated with HIV.

RESULTS

In 793 635 people living with HIV and a total follow-up of 3.5 million person-years, the crude rate of cardiovascular disease was 61.8 (95% CI, 45.8-83.4) per 10 000 person-years. In comparison with individuals without HIV, the risk ratio for cardiovascular disease was 2.16 (95% CI, 1.68-2.77). Over the past 26 years, the global population-attributable fraction from cardiovascular disease attributable to HIV increased from 0.36% (95% CI, 0.21%-0.56%) to 0.92% (95% CI, 0.55%-1.41%), and DALYs increased from 0.74 (95% CI, 0.44-1.16) to 2.57 (95% CI, 1.53-3.92) million. There was marked regional variation with most DALYs lost in sub-Saharan Africa (0.87 million, 95% CI, 0.43-1.70) and the Asia Pacific (0.39 million, 95% CI, 0.23-0.62) regions. The highest population-attributable fraction and burden were observed in Swaziland, Botswana, and Lesotho.

CONCLUSIONS

People living with HIV are twice as likely to develop cardiovascular disease. The global burden of HIV-associated cardiovascular disease has tripled over the past 2 decades and is now responsible for 2.6 million DALYs per annum with the greatest impact in sub-Saharan Africa and the Asia Pacific regions.

CLINICAL TRIAL REGISTRATION

URL: https://www.crd.york.ac.uk/prospero . Unique identifier: CRD42016048257.

NeuroAIDS in children

The human immunodeficiency virus-1 (HIV-1) enters the central nervous system compartment within the first few weeks of systemic HIV infection and may cause a spectrum of neurologic complications. Without combination antiretroviral therapy (cART), 50-90% of all HIV-infected infants and children develop some form of neuroAIDS. Of the estimated 2.3 million children less than 15 years of age who were living in sub-Saharan Africa at the end of 2014, only 30% were receiving cART, suggesting that there is a large burden of neuroAIDS among HIV-infected children in sub-Saharan Africa. There is complex interplay between the disease process itself, the child's immune reaction to the disease, the secondary complications, the side-effects of antiretroviral drugs, and inadequate antiretroviral drug uptake into the central nervous system. In addition there is the layering effect from the multiple socioeconomic challenges for children living in low- and middle-income countries. Adolescents may manifest with a range of neurocognitive sequelae from mild neurocognitive disorder through to severe neurocognitive impairment. Neuroimaging studies on white-matter tracts have identified dysfunction, especially in the frontostriatal networks needed for executive function. Psychiatric symptoms of depression, attention deficit hyperactivity disorder, and behavioral problems are also commonly reported in this age group. Antiretroviral drugs may cause treatment-limiting neurologic and neuropsychiatric adverse reactions. The following chapter addresses the neurologic complications known to be, and suspected of being, associated with HIV infection in children and adolescents.

Extensive cerebrovascular disease and stroke with prolonged prodromal symptoms as first presentation of perinatally-acquired human immunodeficiency virus infection in a young adult

A 26-year-old black African woman presented with an acute onset of hemiparesis and visual symptoms. This had been preceded several months by symptoms which were apparently psychiatric in nature. She had no apparent risk for cerebrovascular disease. Neurological evaluation revealed a striking burden of cerebrovascular disease for her age, including the rare stroke syndrome of basilar artery occlusion. Human immunodeficiency virus (HIV) infection was identified during clinical assessment. This was judged to be perinatally acquired, as there was no history of sexual debut or blood transfusion; her mother was taking antiretroviral therapy and she had facial planar warts and underlying bronchiectasis. Therefore, it has been concluded that presentation of stroke should prompt HIV testing in young people and perinatally-acquired infection can present in adulthood.

Cerebrovascular injury in cryptococcal meningitis

Background

Cryptococcal meningitis continues to be one of the common causes of chronic central nervous system infection worldwide. Individuals with cryptococcal meningitis can occasionally present with small vessel vasculitis causing infarcts primarily in the basal ganglia, internal capsule, and thalamus. Literature regarding patterns of cerebrovascular injury among patients with cryptococcal meningitis is scanty, and outcome following these vascular involvements is unknown.

Aim

To study the clinical profile, imaging findings, and details of vascular territory involved among patients admitted with cryptococcal meningitis and central nervous system infarct in a tertiary care center from India. And to compare the outcomes of patients of cryptococcal meningitis with or without central nervous system infarcts in terms of mortality and morbidity,

Methodology

A total of 151 patients with microbiologically proven cryptococcal meningitis over a time span of 11 years were retrospectively enrolled into the study. Of these, 66 patients met the inclusion criteria of having appropriate imaging of the brain. The presence of infarct in the imaging was analyzed by two independent radiologists. Patterns of central nervous system involvement and types of vascular injury were ascertained based on radiological parameters. Clinical parameters and outcomes of patients with and without infarcts were compared.

Results

Twenty (13%) of these patients had evidence of central nervous system infarcts on imaging. The mean age of patients with and without infarcts was 41 years and 38 years, respectively. Male predominance was present among both the groups. The presence of fever, neck stiffness, positive blood culture, and hydrocephalus in central nervous system imaging was similar among patients with or without infarct. Longer duration of illness, low sensorium at the time of presentation, low Glasgow Coma Scale score, presence of meningeal inflammation, cryptococcomas, and basal exudates in imaging were higher in patients with infarct. All the infarcts were of the lacunar type. Sixty percent of the cerebrovascular infarcts were acute in nature, 50% of these being multiple. Unilateral infarcts were seen in 70% of the patients. The most common site of infarct was the basal ganglia, others being distributed over the thalamus, frontal, temporal, parieto-occipital regions in the descending order. The presence of neurovascular involvement in the form of infarcts to the risk of morbidity and mortality had an odds ratio of 9.1 and 2.6, respectively.

Conclusion

Neurovascular involvement in chronic cryptococcal meningitis is a rare entity. These tend to present as multiple lacunar infarcts. Mortality and morbidity associated with these patients is higher when compared to patients who do not have infarcts. This result suggests that vascular injury plays a role in predicting outcome of patients with cryptococcal meningitis. Future studies are needed to understand the mechanism by which vascular events (infarcts) occur and result in poor outcome.

Greater Risk of Stroke of Undetermined Etiology in a Contemporary HIV-Infected Cohort Compared with Uninfected Individuals

BACKGROUND

Although ischemic stroke risk is increased among people living with HIV infection, little is known about the epidemiology of ischemic stroke subtypes in contemporary HIV-infected cohorts. We examined the distribution of ischemic stroke subtypes among predominantly treated HIV-infected individuals to determine if and how the distribution differs from that of the general population.

METHODS

We studied 60 HIV-infected and 60 HIV-uninfected adults with a history of first-ever ischemic stroke between 2000 and 2012. Ischemic strokes were classified as 1 of 5 subtypes based on established criteria. We used multinomial logistic regression models to compare the relative frequency of ischemic stroke subtypes by HIV status.

RESULTS

Large artery atherosclerosis (23%) and stroke of undetermined etiology (23%) were the most common stroke subtypes among HIV-infected individuals. The most recent plasma HIV viral load before the stroke event differed by subtype, with a median undetectable viral load for individuals with large artery stroke and stroke of undetermined etiology. Using cardioembolic stroke as the reference subtype, HIV-infected individuals were at higher proportional risk of stroke of undetermined etiology compared with uninfected individuals (relative risk ratio [RRR]: 8.6, 95% confidence interval [CI]: 1.2-63.7, P = .04). Among HIV-infected individuals with virologically suppressed infection, we observed a trend toward a greater proportion of strokes attributable to large artery atherosclerosis (RRR: 6.7, 95% CI: .8-57.9, P = .08).

CONCLUSIONS

HIV-infected individuals may be at greater proportional risk of stroke of undetermined etiology compared with uninfected individuals. Further investigation is warranted to confirm this finding and determine underlying reasons for this greater risk.

Increased Cortical Cerebral Blood Flow in Asymptomatic Human Immunodeficiency Virus-Infected Subjects

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals are at high risk for ischemic stroke. To investigate the physiological basis for this risk, we used magnetic resonance imaging (MRI) to measure oxygen extraction fraction (OEF) and cerebral blood flow (CBF) in treatment-naive asymptomatic HIV-infected subjects and controls.

METHODS

In treatment-naive asymptomatic HIV-infected subjects and age-, gender-, and race-matched controls, OEF was measured by MRI asymmetric spin-echo echo-planar imaging sequences and CBF was measured by MRI pseudocontinuous arterial spin labeling.

RESULTS

Twenty-six treatment-naive HIV-infected subjects and 27 age-, gender-, race-matched controls participated. Whole-brain, gray matter (GM), and white matter OEF were not different between the groups (all P > .70). Unexpectedly, HIV-infected subjects had significantly higher CBF in cortical GM (72.9 ± 16.2 mL/100 g/min versus 63.9 ± 9.9 mL/100 g/min; P = .01) but not in subcortical GM (P = .25).

CONCLUSIONS

The observed increase in cortical GM CBF in treatment-naive HIV-infected subjects is unexpected, contrary to CBF decreases reported in HIV-infected subjects on treatment, and may represent an initial increase in metabolic activity due to an HIV-mediated inflammation.

Cerebrovascular disease in children with HIV-1 infection

An estimated 3.2 million children worldwide have human immunodeficiency virus (HIV) infection. Antiretroviral therapy (ART) has resulted in prolonged survival, leading to an increase in complications previously recognized in adults. Children with HIV infection have increased risk of cerebrovascular disease from multiple aetiologies including HIV-associated vasculopathy, opportunistic vasculitis, cardioembolism or coagulopathy, all of which may be secondary to the infection. Prevalence of cerebrovascular disease in HIV-infected children is underestimated because of limited neuroimaging in low and middle income countries, silent events without overt motor manifestations, and mislabeling as HIV encephalopathy for non-motor manifestations such as behavioural and cognitive difficulties. No management guidelines for cerebrovascular disease in HIV-infected children exist but common practices target risk factors for stroke in low and middle income countries. Where capacity permits, screening for opportunistic infections, vasculitis, coagulopathy and cardioembolism is important. Optimising virological suppression, correction of anaemia, control of seizures and aspirin prophylaxis are management priorities. Neurosurgical interventions may have a role.

Stroke risk factors in an incident population in urban and rural Tanzania: a prospective, community-based, case-control study

BACKGROUND

The burden of stroke on health systems in low-income and middle-income countries is increasing. However, high-quality data for modifiable stroke risk factors in sub-Saharan Africa are scarce, with no community based, case-control studies previously published. We aimed to identify risk factors for stroke in an incident population from rural and urban Tanzania.

METHODS

Stroke cases from urban Dar-es-Salaam and the rural Hai district were recruited in a wider study of stroke incidence between June 15, 2003, and June 15, 2006. We included cases with fi rst-ever and recurrent stroke. Community-acquired controls recruited from the background census populations of the two study regions were matched with cases for age and sex and were interviewed and assessed. Data relating to medical and social history were recorded and blood samples taken.

FINDINGS

We included 200 stroke cases (69 from Dar-es-Salaam and 131 from Hai) and 398 controls (138 from Dar-es-Salaam and 260 from Hai). Risk factors were similar at both sites, with previous cardiac event (odds ratio [OR] 7.39, 95% CI 2.42-22.53; p<0.0001), HIV infection (5.61, 2.41-13.09; p<0.0001), a high ratio of total cholesterol to HDL cholesterol (4.54, 2.49-8.28; p<0.0001), smoking (2.72, 1.49-4.96; p=0.001), and hypertension (2.14, 1.09-4.17; p=0.026) identified as significant independent risk factors for stroke. In Hai, additional risk factors of diabetes (4.04, 1.29-12.64) and low HDL cholesterol (9.84, 4.06-23.84) were also significant.

INTERPRETATION

We have identified many of the risk factors for stroke already reported for other world regions. HIV status was an independent risk factor for stroke within an antiretroviral-naive population. Clinicians should be aware of the increased risk of stroke in people with HIV, even in the absence of antiretroviral treatment.

Update on the key developments of the neurologic complications in children infected with HIV

PURPOSE OF REVIEW

To discuss recent research findings of neurologic complications in HIV-infected children, specifically addressing neuroinfections, cerebrovascular disease, epilepsy and neurocognitive complications. The range of neurologic childhood onset complications is diverse and often overlaps diseases previously considered only to manifest in adults. In the pediatric population, these complications frequently have their own unique disease identity, which may be related to maturational patterns evident in the developing brain.

RECENT FINDINGS

Developments regarding the pathogenesis of neuroAIDS, treatment of tuberculous meningitis and prevention of bacterial meningitis are described. With the advent of neuroimaging, there is greater insight into silent cerebrovascular events and the progression of vasculopathy in HIV-infected children. The role of surgical intervention for affected cases is a novel area that could alter the otherwise poor prognosis. Epilepsy, although common as a burden of disease, carries its own additional complications with regard to cross reactivity with various antiretroviral therapies. Increased risk of low bone mineral density supports a role for supplementation with vitamin D in people receiving antiretroviral therapy and antiepileptic drugs. Recognition of the early neurobiological, as well as spectrum of neurocognitive effects of the HIV on the developing brain, is evolving, as greater numbers of children are treated early. Developments in these critical areas are described.

SUMMARY

Recent research reflects the need for improved strategies to prevent neuroinfections, more effective screening and interventions for vasculopathy and better antiepileptic drugs for HIV-infected children. Furthermore, our understanding of the timing and spectrum of neurocognitive complications is evolving.

HIV status and the risk of ischemic stroke among men

OBJECTIVE

Given conflicting data regarding the association of HIV infection and ischemic stroke risk, we sought to determine whether HIV infection conferred an increased ischemic stroke risk among male veterans.

METHODS

The Veterans Aging Cohort Study-Virtual Cohort consists of HIV-infected and uninfected veterans in care matched (1:2) for age, sex, race/ethnicity, and clinical site. We analyzed data on 76,835 male participants in the Veterans Aging Cohort Study-Virtual Cohort who were free of baseline cardiovascular disease. We assessed demographics, ischemic stroke risk factors, comorbid diseases, substance use, HIV biomarkers, and incidence of ischemic stroke from October 1, 2003, to December 31, 2009.

RESULTS

During a median follow-up period of 5.9 (interquartile range 3.5-6.6) years, there were 910 stroke events (37.4% HIV-infected). Ischemic stroke rates per 1,000 person-years were higher for HIV-infected (2.79, 95% confidence interval 2.51-3.10) than for uninfected veterans (2.24 [2.06-2.43]) (incidence rate ratio 1.25 [1.09-1.43]; p < 0.01). After adjusting for demographics, ischemic stroke risk factors, comorbid diseases, and substance use, the risk of ischemic stroke was higher among male veterans with HIV infection compared with uninfected veterans (hazard ratio 1.17 [1.01-1.36]; p = 0.04).

CONCLUSIONS

HIV infection is associated with an increased ischemic stroke risk among HIV-infected compared with demographically and behaviorally similar uninfected male veterans.

Infectious causes of stroke

Most infectious pathogens have anecdotal evidence to support a link with stroke, but certain pathogens have more robust associations, in which causation is probable. Few dedicated prospective studies of stroke in the setting of infection have been done. The use of head imaging, a clinical standard of diagnostic care, to confirm stroke and stroke type is not universal. Data for stroke are scarce in locations where infections are probably most common, making it difficult to reach conclusions on how populations differ in terms of risk of infectious stroke. The treatment of infections and stroke, when concomitant, is based on almost no evidence and requires dedicated efforts to understand variations that might exist. We highlight the present knowledge and emphasise the need for stronger evidence to assist in the diagnosis, treatment, and secondary prevention of stroke in patients in whom an infectious cause for stroke is probable.

Cerebral infarction in an HIV-infected patient with combined protein S and C deficiency and a patent foramen ovale

A 41-year-old male with a history of human immunodeficiency virus (HIV) infection developed motor aphasia, dysarthria, and right hemiparesis. A magnetic resonance imaging scan of the brain revealed a cerebral infarction in the territory of the left middle cerebral artery. The laboratory data showed decreased levels of protein S and protein C. Transesophageal contrast-enhanced echocardiography revealed a patent foramen ovale (PFO). Prothrombotic states, such as protein S and C deficiency, have been reported in HIV-infected patients. In addition, previous studies have reported prothrombotic states to be risk factors for PFO-related cerebral infarction. An association between combined protein S and C deficiency caused by HIV infection and PFO-related cerebral infarction was suggested in our patient.

HIV stroke risk: evidence and implications

An estimated 34 million men, women, and children are infected with human immunodeficiency virus type 1 (HIV-1), the virus that causes acquired immunodeficiency syndrome (AIDS). Current technology cannot eradicate HIV-1, and most patients with HIV-1-infection (HIV+) will require lifelong treatment with combined antiretroviral therapy (cART). Stroke was recognized as a complication of HIV-1 infection since the early days of the epidemic. Potential causes of stroke in HIV-1 include opportunistic infections, tumors, atherosclerosis, diabetes, hypertension, autoimmunity, coagulopathies, cardiovascular disease, and direct HIV-1 infection of the arterial wall. Ischemic stroke has emerged as a particularly significant neurological complication of HIV-1 and its treatment due to the aging of the HIV+ population, chronic HIV-1 infection, inflammation, and prolonged exposure to cART. New prevention and treatment strategies tailored to the needs of the HIV+ population are needed to address this issue.

Central Nervous System Vasculopathy in HIV-Infected Children Enrolled in the Pediatric AIDS Clinical Trials Group 219/219C Study

BACKGROUND

Central nervous system (CNS) vasculopathy has been reported in human immunodeficiency virus-infected (HIV+) adults and children. In children, it often presents with HIV encephalopathy, stroke, or intracerebral aneurysms. The etiology, incidence, and risk factors of HIV-associated CNS vasculopathy in children are unknown.

METHODS

We identified HIV+ children with a diagnosis of vasculopathy or other cerebrovascular events among children enrolled between 1993 and 2004 in 2 prospective, multicenter cohort studies. Demographic and laboratory data, history of antiretroviral use, and signs, symptoms, and diagnostic studies pertaining to the CNS event were reviewed.

RESULTS

Among the 3338 HIV+ children, 51 had diagnoses that suggested CNS vasculopathy. Of these, 12 (24%) were included in this analysis, after excluding those with alternative diagnoses and those from closed sites. Among these 12, 4 (33%) were female, 4 (33%) were white, and 10 (83%) had perinatal HIV. Their average age at the event was 10.8 years with a median CD4 count of 22 cells/mm(3) and median HIV-1 viral load of 94 304 copies/mL. Fifty-eight percent of subjects had a history of opportunistic infections before the CNS event. Fifty percent had cerebral aneurysms on imaging. The overall incidence among HIV+ subjects was 3.4 cases per 10 000 person-years (95% confidence interval, 1.8-6.0).

CONCLUSIONS

CNS vasculopathy in HIV+ children is uncommon but more common than in the general pediatric population. Cerebral aneurysms are the most common manifestation. Although the pathogenesis remains unclear, older children and those with low CD4 counts and high HIV viral loads are at the highest risk.

Neuroimaging studies of the aging HIV-1-infected brain

Highly active antiretroviral therapy (HAART) has increased life expectancy among HIV-infected individuals, and by 2015, at least half of all HIV-infected individuals will be over 50 years of age. Neurodegenerative processes associated with aging may be facilitated by HIV-1 infection, resulting in premature brain aging. This review will highlight brain abnormalities in HIV patients in the setting of aging, focusing on recent neuroimaging studies of the structural, physiological, functional and neurochemical changes. Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy studies performed during the pre-HAART era or on antiretroviral-naive subjects suggest an accelerated aging process, while those on HAART-treated subjects suggest premature brain atrophy. Diffusion tensor imaging studies yielded conflicting findings on the relationship between HIV and age in neuroasymptomatic individuals. Functional MRI studies found evidence of premature or accelerated aging processes in the brains of HIV subjects. Lastly, many age-related illnesses such as diabetes, stroke, and depression, as well as comorbid substance abuse, may further exacerbate the aging process in the HIV-infected brain, leading to premature or accelerated age-related brain changes. Given the different pathologic or physiologic changes in the brain assessed by the different neuroimaging techniques, using a multimodal approach in longitudinal follow-up studies is recommended for future studies.

Cerebrovascular disease in HIV-infected individuals in the era of highly active antiretroviral therapy

The widespread use of highly active antiretroviral therapy (HAART) in HIV-infected individuals mostly in developed countries has dramatically improved their prognosis. In such advantaged regions of the world, therefore, many patients are now transitioning from middle into older age, with altered patterns of disease. While previously a rare complication of HIV infection, cerebrovascular disease (particularly that associated with atherosclerosis) is becoming relatively more important in this treated group of individuals. This review summarises the evidence regarding the shifting epidemiology of cerebrovascular diseases affecting HIV-infected individuals. While outlining the association between HIV infection and AIDS and cerebrovascular disease, as well as opportunistic diseases and HIV-associated vasculopathies, the current evidence supporting an increase in atherosclerotic disease in treated HIV-infected individuals is emphasised and a management approach to ischaemic stroke in HIV-infected individuals is presented. Evidence supporting the important role of HAART and HIV infection itself in the pathogenesis of atherosclerotic disease is discussed, together with preventative approaches to this increasingly important disease process as the population ages. Finally, a discussion regarding the significant association between cerebrovascular disease and HIV-associated neurocognitive disorder is presented, together with possible mechanisms behind this relationship.

Recent developments regarding human immunodeficiency virus infection and stroke

Human immunodeficiency virus (HIV) infection is strongly associated with ischemic stroke in the young. Data obtained from the Nationwide Inpatient Sample in the United States show an increase in the number of stroke hospitalizations in the HIV-infected population despite an overall decrease in the number of stroke hospitalizations. Few data exist, however, that address the mechanism of HIV-associated stroke. Recent studies have demonstrated that HIV may infect the endothelium and alter cerebrovascular functions. Whether the proposed mechanism alters the stroke risk is undetermined. Epidemiological studies suggest that HIV-related stroke is associated with a risk factor profile that differs from the HIV-negative young stroke population in that HIV-associated strokes are less likely to have hypertension, diabetes, hyperlipidemia and smoking as risk factors. A large population-based study, moreover, suggests an association between antiretroviral therapy and increased cardio- and cerebrovascular risks. Specific antiretroviral agents such as protease inhibitors and non-nucleoside reverse transcriptase inhibitors have been implicated in the metabolic syndrome, accelerated atherosclerosis and an increased risk for ischemic stroke. In addition to discussing these developments, this paper also discusses the implications of recent data for stroke prevention in HIV-infected patients.

Neurologic and neurobehavioral sequelae in children with human immunodeficiency virus (HIV-1) infection

The range and extent of neurologic and neurobehavioral complications of human immunodeficiency virus (HIV-1) infection in children are under-described. Seventy-eight children with HIV-1 infection (32 females) were assessed for neurologic complications. Forty-six children had abnormal neurology examinations. Thirty-three children had global pyramidal tract signs, 5 had a hemiparesis, 4 had peripheral neuropathy, 18 had visual impairment, and 5 had hearing impairment. Thirty-nine of 63 children over 1 year of age had neurobehavioral problems. Of 24 children with HIV encephalopathy, 74% had severe immunosuppression and 45% were not receiving antiretroviral therapy. Twelve children had prior opportunistic central nervous system infections, and 9 had epilepsy. Diverse neurologic and neurobehavioral deficits are common in children with HIV-1 infection. Children with severe immunosuppression, who were not receiving antiretroviral therapy, were growth impaired and less than 1 year of age, were at greatest risk for developing neurologic complications.

Risk of cerebrovascular events in persons with and without HIV: a Danish nationwide population-based cohort study

OBJECTIVE

To assess the risk of cerebrovascular events (CVEs) in HIV-infected individuals and evaluate the impact of proven risk factors, injection drug abuse (IDU), immunodeficiency, HAART and family-related risk factors.

DESIGN

Nationwide, population-based cohort study.

METHODS

The study population included all Danish HIV-infected individuals, a population-based comparison cohort and parents of both cohorts - all with no prior cerebral comorbidity. We computed incidence rate ratios (IRRs) of overall CVEs and CVEs with and without proven risk factors, stratifying the analyses on IDU. Impact of immunodeficiency, HAART, protease inhibitors, indinavir, didanosin, tenofovir and abacavir on risk of CVEs was analyzed using time-dependent Cox regression analyses.

RESULTS

HIV-infected individuals had an increased risk of CVEs compared with the comparison cohorts [(non-IDU HIV adjusted IRR 1.60; 95% confidence interval [CI] 1.32-1.94), (IDU HIV adjusted IRR 3.94; 95% CI 2.16-7.16)]. The risk was increased with and without proven risk factors. A CD4 cell count of 200 cells/μl or less before the start of HAART and exposure to abacavir increased the risk of CVE [(adjusted IRR 2.26; 95% CI 1.05-4.86) and (adjusted IRR 1.66; 95% CI 1.03-2.68)]. Protease inhibitors, indinavir, didanosin, tenofovir and HAART in general had no impact. Risk of CVEs was only increased in the parents of IDU HIV-infected individuals.

CONCLUSION

HIV-infected individuals have an increased risk of CVEs with and without proven risk factors. The risk is associated with IDU, low CD4 cell count and exposure to abacavir, but not with HAART. An association with family-related risk factors seems vague except for parents of IDU individuals.

Relationship between Younger Age, Autoimmunity, Cardiometabolic Risk, Oxidative Stress, HAART, and Ischemic Stroke in Africans with HIV/AIDS

Background and Purpose. It now appears clear that both HIV/AIDS and antiretroviral therapy (HAART) use are associated with higher risk of cardiovascular disease such as stroke. In this study, we evaluated the prevalence, the risk factors, and the cardiometabolic comorbidities of stroke in HIV/AIDS Central African patients. Methods. This hospital-based cross-sectional study collected clinical, laboratory, and imaging data of black Central African heterosexual, intravenous drug nonuser, and HIV/AIDS patients. Results. There were 54 men and 62 women, with a female to male ratio of 1.2 : 1. All were defined by hypercoagulability and oxidative stress. Hemorrhagic stroke was reported in 1 patient, ischemic stroke in 17 patients, and all stroke subtypes in 18 patients (15%). Younger age <45 years (P = .003), autoimmunity (P < .0001), and metabolic syndrome defined by IDF criteria (P < .0001) were associated with ischemic stroke. Conclusions. Clustering of several cardiometabolic factors, autoimmunity, oxidative stress, and lifestyle changes may explain accelerated atherosclerosis and high risk of stroke in these young black Africans with HIV/AIDS. Prevention and intervention programs are needed.

Stroke: a realistic approach to a growing problem in sub-Saharan Africa is urgently needed

Stroke is an increasing problem in sub-Saharan Africa, even in children. High rates of hypertension, diabetes, alcohol abuse, smoking, insufficient fruit and vegetable consumption, sickle cell disease, HIV infection, antiretroviral use and race are likely contributing factors. Although often considered as related to increasing wealth, stroke is more strongly related to poverty, and in turn increases it. Case-fatality rates are high and premature death and years of life lost are a major problem. We propose an approach to stroke prevention and treatment that takes into account the real situation on the ground and can be applied in sub-Saharan Africa, an area where stroke units are largely not feasible and many patients do not reach hospitals. Involvement of community and faith-based organisations, use of simple diagnostic tests, emphasis on clinical examination to differentiate between haemorrhagic and ischaemic stroke, prompt initiation of aspirin therapy and training of community nurses on essential management of stroke should be urgently implemented.

Acute/subacute cerebral infarction (ASCI) in HIV-negative adults with cryptococcal meningoencephalitis (CM): a MRI-based follow-up study and a clinical comparison to HIV-negative CM adults without ASCI

BACKGROUND

Acute/subacute cerebral infarction (ASCI) in HIV-negative cryptococcal meningoencephalitis (CM) adults has rarely been examined by a series of MRI-based follow-up study. We studied a series of MRI follow-up study of CM adults and compared the clinical characters of those with ASCI and those without ASCI.

METHODS

The clinical characteristics and a series of brain MRI findings of seven CM adults with ASCI were enrolled for analysis. The clinical characteristics of another 30 HIV-negative CM adults who did not have ASCI were also included for a comparative analysis.

RESULTS

The seven HIV-negative CM adults with ASCI were four men and three women, aged 46-78 years. Lacunar infarction was the type of ASCI, and 86% (6/7) of the ACSI were multiple infarctions distributed in both the anterior and posterior cerebrovascular territories. The seven CM patients with ASCI were significantly older and had a higher rate of DM and previous stroke than the other 30 CM adults without ASCI. They also had a higher incidence of consciousness disturbance at presentation and had a poor prognosis.

CONCLUSION

ASCI was found in 18.9% (7/37) of HIV-negative CM adults. Serial MRI follow-up studies may allow a better delineation of ASCI in this specific group of infectious disease and multiple lacunar infarctions was the most common type. Older in age and presence of DM and previous stroke were the significant underlying conditions. CM patients with ASCI also had a poor therapeutic outcome.

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.

Stroke in young Nigerian adults

Stroke in adults under the age of 45 results in a greater loss of potential years of life than for other adults. This premature loss of life is associated with a high social and economic burden. Few data are available regarding stroke among young Nigerian adults in the Niger Delta Basin. This study sought to determine the incidence, risk factors, stroke subtypes and case fatality of stroke among young Nigerian adults. The medical records of all 18- to 45-year-old patients admitted with stroke in the medical wards of the University of Port Harcourt Teaching Hospital (UPTH) from January 2003 to December 2008 were retrospectively reviewed. Of the 611 patients admitted with stroke, 54 (8.8%) were aged 18-45 years. There were 26 males and 28 females. Hypertension was responsible for 42 (77.8%) stroke cases. Other important risk factors were excessive alcohol intake (27.8%), heart disease (13%), diabetes mellitus (11.1%), cigarette smoking (11.1%) and HIV infection (7.4%). The total case fatality was 29.6% with intracerebral hemorrhage (ICH) having higher case fatality of 69.2% than cerebral infarction (CI) with a case fatality of 16.7%. Among the young Nigerian adults who presented with stroke, 53.7% survived. The authors conclude from the above information that the incidence of stroke in young patients at UPTH is low. Hypertension is the most important risk factor of stroke; however, other less common but important risk factors in the young adults are cigarette smoking, diabetes mellitus and HIV. Efforts should be made to reduce the impact of stroke in this age group by focusing on these risk factors, which are either preventable or modifiable.

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

Metabolic syndrome (MetS) is a cluster of risk factors, including elevated mean arterial pressure (MAP), atherogenic dyslipidemia (elevated triglycerides [TRG]), abdominal obesity (increased body mass index [BMI]), glucose intolerance (elevated glucose [GLU]), and prothrombotic/inflammatory state (increases in uric acid [UA]), that are associated with increased risk of cerebrovascular disease. We studied if an association existed between MetS components and human immunodeficiency virus (HIV)-associated cryptogenic strokes-those not caused by HIV complications, endocarditis, or stimulant abuse. We performed a retrospective case-control study. Eleven cryptogenic strokes were identified from 2346 HIV-infected (HIV+) participants. Each case was matched by age, sex, and date of stroke diagnosis to five HIV+ controls without stroke. Nonparametric stratified Wilcoxon ranked sum tests with subsequent mixed effect logistic regression determined the influence of each MetS component on HIV-associated cryptogenic stroke. Although each MetS component appeared higher for HIV+ cases with cryptogenic strokes than HIV+ controls, only MAP (odds ratio [OR] = 5.70, 95% confidence interval [CI] = 1.15-28.3) and UA (OR = 1.88, 95% CI = 1.06-3.32) were statistically different. A significantly higher percentage of HIV-associated cryptogenic stroke cases met criteria for MetS (4/11 = 36%) compared to HIV+ controls (6/55 = 11%). This observational study suggests a possible role for MetS components in HIV+ cryptogenic stroke cases. Although MetS is defined as a constellation of disorders, elevated hypertension and hyperuricemia may be involved in stroke pathogenesis. Reducing MetS component levels in HIV+ patients could therefore protect them from subsequent stroke.

Is stroke a HIV-related neurologic manifestation?

Neurologic illnesses occur commonly in association with HIV infection, are frequently debilitating and often life-threatening. The commonly recognized HIV-related neurologic illnesses include encephalopathy (dementia), myelopathy, neuropathy and myopathy. Stroke as a HIV-related manifestation is an increasingly recognized and evolving issue. This article reviews the literature on the association of stroke and HIV, stroke risk and stroke mechanisms in HIV-infected patients, and the role of antiretroviral drugs in HIV-related stroke.

Stroke in patients with human immunodeficiency virus infection

OBJECTIVE

To report the nature of stroke in patients infected with human immunodeficiency virus (HIV) in a region with high HIV seroprevalence and describe HIV associated vasculopathy.

METHODS

Patients with first ever stroke, infected with HIV and prospectively included in the stroke register of the Groote Schuur Hospital/University of Cape Town stroke unit were identified and reviewed.

RESULTS

Between 2000 and 2006, 67 of the 1087 (6.1%) stroke patients were HIV infected. Of these, 91% (n = 61) were younger than 46 years. Cerebral infarction occurred in 96% (n = 64) of the HIV positive patients and intracerebral haemorrhage in 4% (n = 3). HIV infected young stroke patients did not demonstrate hypertension, diabetes, hyperlipidaemia or smoking as significant risk factors for ischaemic stroke. Infection as a risk factor for stroke was significantly more common in HIV positive patients (p = 0.018, OR 6.4, CI 3.1 to 13.2). In 52 (81%) patients with ischaemic stroke, an aetiology was determined. Primary aetiologies comprised infectious meningitides/vasculitides in 18 (28%) patients, coagulopathy in 12 (19%) patients and cardioembolism in nine (14%) patients. Multiple aetiologies were present in seven (11%) patients with ischaemic stroke. HIV associated vasculopathy was identified in 13 (20%) patients. The HIV associated vasculopathy manifested either extracranially (seven patients) as total or significant carotid occlusion or intracranially (six patients) as medium vessel occlusion, with or without fusiform aneurysmal dilation, stenosis and vessel calibre variation.

CONCLUSION

Investigation of HIV infected patients presenting with stroke will determine an aetiology in the majority of patients. In our cohort, 20% of patients demonstrated evidence of an HIV associated vasculopathy.

Time course of cerebral hemodynamics in cryptococcal meningitis in HIV-negative adults

To evaluate the cerebral hemodynamics in cryptococcal meningitis (CM) patients using non-invasive studies. Serial trans-cranial color-coded sonography (TCCS) and magnetic resonance angiography (MRA) studies were performed to measure the cerebral vasculopathy of 12 HIV-negative CM patients. With TCCS, 8 of the 22 middle cerebral arteries (MCAs) showed stenotic velocities, whereas the time-mean velocity (V(mean)) of the 20 anterior cerebral arteries (ACAs), 22 posterior cerebral arteries (PCAs), and 12 basilar arteries (BAs) did not. In total, five patients had stenotic velocities, three of whom had bilateral M1 stenosis (<50%), whilst two had unilateral M1 stenosis (<50%). The V(mean) of MCA increased from day 1 to day 35 and substantially decreased thereafter. The mean Pulsatility Index (PI) in the studied vessels was higher during the study period. A mismatch of the findings between TCCS and MRA studies were also demonstrated. There was a high incidence and a longer time-period of disturbed cerebral hemodynamics during the clinical course of CM. However, because of the limited case numbers for this study, further large-scale studies are needed to delineate the clinical characteristics and therapeutic influence of cerebrovascular insults in HIV-negative CM patients.

Cerebrovascular disease in highly active antiretroviral therapy-treated individuals: incidence and risk factors

The occurrence of cerebrovascular events in patients infected by human immunodeficiency virus (HIV) has been traditionally associated with opportunistic infections and tumors, and/or advanced stages of immunosuppression. The current use in the clinical practice of antiretroviral treatment (ART) has been associated with a dramatic reduction of HIV-related mortality. Due to the increase of median age of HIV-infected subjects and to the ART-induced lipid abnormalities, an increasing incidence of vascular complications has been reported in this population. The potential contribution of these novel mechanisms should be considered and added to the classic vascular risk factors in the HIV-infected population and the cardiac abnormalities frequently observed in these patients. Large-scale epidemiological studies are needed to better define the incidence of cerebrovascular events in HIV-infected patients and the factors associated with their occurrence.

Spontaneous artery dissection in a patient with Human Immunodeficiency Virus (HIV) infection

BACKGROUND

The relationship between human immunodeficiency virus infection and stroke may be attributed in some cases to an underlying vasculopathy such as in spontaneous cervical arteries dissections.

CASE REPORT

We report the case of an HIV-infected patient who developed a Wallemberg's syndrome due to a vertebral artery dissection. Screening laboratory exams showed hyperhomocysteinemia and also high C-reactive protein plasma levels.

CONCLUSIONS

This is the first case describing the association between arterial dissection (AD) and HIV-infection. We suggest that AD should also be remembered as a possible mechanism of ischemic stroke in HIV-infected patients.

HIV Infection and Dementia in Older Adults

Human immunodeficiency virus (HIV) infection in older patients is becoming increasingly common as seropositive individuals live longer because of long-term antiretroviral treatment. Simultaneously, the development and expression of dementia among HIV-infected patients is evolving in the era of highly active antiretroviral therapy (HAART) and immune reconstitution. How long-term HAART interacts with chronic HIV infection and advanced age with regard to cognition is not fully understood. This article provides an overview of HIV cognitive impairment as it relates to aging and presents some emerging issues in the field. Particular emphasis is placed on describing the changing landscape of HIV-related cognitive impairment and discussing possible concerns regarding the long-term effects of antiretroviral treatment. A brief discussion of potential adjunctive therapies to reduce cognitive symptoms associated with HIV infection in older individuals is provided.

Unusual thromboses associated with protein S deficiency in patients with acquired immunodeficiency syndrome: case reports and review of the literature

Recent reports indicate that patients infected with HIV are at increased risk for the development of thrombosis. Among other possibilities, an acquired deficiency of protein S (PS), one of the plasma's natural anticoagulants, might explain this tendency. PS deficiency can be classified in three types depending on the levels of total and free protein (antigenic assays) as well as anticoagulant activity (functional assay). Although the prevalence of inherited PS deficiency is not known because of its rarity, several conditions can lead to acquired forms of the disease. We report two AIDS patients with coexistent type III PS deficiency and thrombosis. Our first patient presented with bilateral chronic leg ulcers and a skin biopsy revealed dermal microthromboses. On laboratory evaluation he had PS deficiency and was started on anticoagulation, but was lost to follow-up. The second patient presented with hepatic vein thrombosis (Budd-Chiari syndrome) and was also PS deficient. On long-term anticoagulation, she experienced resolution of the thrombosis. Neither patient had prior personal or family history of venous thrombosis, nor acquired risk factors such as immobility, acute infection, recent surgery, or hormonal therapy. The literature contains a few reports of skin ulcers and Budd-Chiari syndrome associated with PS deficiency, although none in AIDS patients. While a larger number of studies describe an association between PS deficiency and HIV infection, the causal effect of this deficiency on the thrombophilic tendency in AIDS has not been established. We propose that awareness of the increased risk for thrombosis in HIV infection is important to the understanding of disease pathophysiology and management of these patients.

Acquired protein C and protein S deficiency in HIV-infected patients

Infection with human immunodeficiency virus (HIV) may lead to hemostatic imbalances. Forty-nine consecutive patients with acute opportunistic infections were screened for thrombophilic parameters. A follow-up investigation was performed after 10 +/- 8 weeks in 26 patients. In acutely ill patients, the incidence of protein S deficiency was 67% (33/49) and of protein C deficiency 25% (12/49), while at the follow-up visit the incidences were 54% (14/26) and 8% (2/26), respectively. Protein S and protein C levels increased significantly from initial to follow-up visit (p < 0.05). Lupus anticoagulants were not detected and anticardiolipin IgG antibodies were present in 11.4% (5/44). Three patients presented with deep venous thrombosis on admission; in two, protein S or protein C deficiency was observed. In conclusion, an acquired protein S and protein C deficiency often develop in patients with HIV and acute illness; this may be reversible after treatment for opportunistic infections.