HIV, antiretroviral treatment, hypertension, and stroke in Malawian adults: A case-control study

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.

Cognitive Impairment and Persistent CNS Injury in Treated HIV

The implementation of combination antiretroviral therapy (cART) has changed HIV infection into a chronic illness, conveying extensive benefits, including greater longevity and advantages for the central nervous system (CNS). However, studies increasingly confirm that the CNS gains are incomplete, with reports of persistent immune activation affecting the CNS despite suppression of plasma HIV RNA. The rate of cognitive impairment is unchanged, although severity is generally milder than in the pre-cART era. In this review, we discuss cognitive outcomes from recently published clinical HIV studies, review observations on HIV biomarkers for cognitive change, and emphasize longitudinal imaging findings. Additionally, we summarize recent studies on CNS viral invasion, CD8 encephalitis, and how CNS involvement during the earliest stages of infection may set the stage for later cognitive manifestations.

The Role of Human Immunodeficiency Virus-Associated Vasculopathy in the Etiology of Stroke

Background

Human immunodeficiency virus (HIV) infection is a recognized risk factor for stroke among young populations, but the exact mechanisms are poorly understood. We studied the clinical, radiologic, and histologic features of HIV-related ischemic stroke to gain insight into the disease mechanisms.

Methods

We conducted a prospective, in-depth analysis of adult ischemic stroke patients presenting to Queen Elizabeth Central Hospital, Blantyre, Malawi, in 2011.

Results

We recruited 64 HIV-infected and 107 HIV-uninfected patients. Those with HIV were significantly younger (P < .001) and less likely to have established vascular risk factors. Patients with HIV were more likely to have large artery disease (21% vs 10%; P < .001). The commonest etiology was HIV-associated vasculopathy (24 [38%]), followed by opportunistic infections (16 [25%]). Sixteen of 64 (25%) had a stroke soon after starting antiretroviral therapy (ART), suggesting an immune reconstitution-like syndrome. In this group, CD4+ T-lymphocyte count was low, despite a significantly lower HIV viral load in those recently started on treatment (P < .001).

Conclusions

HIV-associated vasculopathy and opportunistic infections are common causes of HIV-related ischemic stroke. Furthermore, subtypes of HIV-associated vasculopathy may manifest as a result of an immune reconstitution-like syndrome after starting ART. A better understanding of this mechanism may point toward new treatments.

Challenges of stroke management in resource-limited settings: A case-based reflection

A 19-year-old man presented with a 1-year history of headache, generalised body weakness, progressive memory loss, and disorientation. One month prior to admission, there was aggravation of the weakness of the right upper limb, with new-onset difficulty with mastication, speech impairment, apathy, and urinary incontinence. On clinical examination, the patient had a motor aphasia and a right-sided hemiparesis with increased muscle tone and hyperreflexia. A noncontrast computed tomography (CT) scan of the brain revealed large ischaemic strokes extending beyond the classical vascular territories. Cerebrospinal fluid analysis showed a mildly increased protein level. The electrocardiogram revealed an irregular sinus bradycardia. The remainder of the cardiovascular and laboratory workup was unremarkable. Considering a working diagnosis of central nervous system vasculitis, the patient was treated with aspirin, prednisolone, and physiotherapy. However, he died suddenly a few weeks later. Based on this case, we discuss the challenges of stroke management in resource-limited settings, provide practical tips for general practitioners, reflect on the potential avenues for short- and long-term action, and introduce the budding collaboration platform between the University College London, the University of Liverpool, the Queen Elizabeth Central Hospital, and the Malawi-Liverpool-Wellcome Trust Clinical Research Programme.

Aging, Health, and Quality of Life for Older People Living With HIV in Sub-Saharan Africa: A Review and Proposed Conceptual Framework

OBJECTIVE

The number of people living with HIV (PLWH) over 50 years old in sub-Saharan Africa is predicted to triple in the coming decades, to 6-10 million. Yet, there is a paucity of data on the determinants of health and quality of life for older PLWH in the region.

METHODS

A review was undertaken to describe the impact of HIV infection on aging for PLWH in sub-Saharan Africa.

RESULTS

We (a) summarize the pathophysiology and epidemiology of aging with HIV in resource-rich settings, and (b) describe how these relationships might differ in sub-Saharan Africa, (c) propose a conceptual framework to describe determinants of quality of life for older PLWH, and (d) suggest priority research areas needed to ensure long-term gains in quality of life for PLWH in the region.

CONCLUSIONS

Differences in traditional, lifestyle, and envirnomental risk factors, as well as unique features of HIV epidemiology and care delivery appear to substantially alter the contribution of HIV to aging in sub-Saharan Africa. Meanwhile, unique preferences and conceptualizations of quality of life will require novel measurement and intervention tools. An expanded research and public health infrastructure is needed to ensure that gains made in HIV prevention and treamtent are translated into long-term benefits in this region.

HIV Infection and Risk of Cardiovascular Diseases Beyond Coronary Artery Disease

PURPOSE OF REVIEW

Cardiovascular disease (CVD) increasingly afflicts people living with HIV (PLWH) in the contemporary era of antiretroviral therapy (ART). Coronary artery disease (CAD) is the most widely studied cardiovascular problem in PLWH; however, less is known about other clinically relevant subtypes of CVD such as heart failure (HF), cerebrovascular disease, sudden cardiac death, pericardial diseases, and pulmonary hypertension. This paper reviews evidence of other subtypes of CVD as emerging issues in the post-ART era.

RECENT FINDINGS

Recent studies have shown that PLWH have higher risk of HF as well as subclinical impairment of left ventricular (LV) mechanics (systolic and diastolic dysfunction) and myocardial abnormalities (fibrosis and steatosis). The underlying mechanisms, however, are not well-understood. A few studies have also shown higher rates of atrial fibrillation and sudden cardiac death in PLWH. Ischemic stroke is the most common stroke type in the post-ART era, with underlying mechanisms like those identified in CAD: chronic inflammation and associated vasculopathy. Studies of great vessels (carotid artery and aorta) and peripheral arterial disease show heterogeneous results. Small subclinical pericardial effusions are common in PLWH in post-ART era. Pulmonary hypertension continues to be an underdiagnosed and potentially fatal complication of HIV infection. PLWH remain at higher risk for all types of CVD including heart failure, stroke, and arrhythmias in the post-ART era. Chronic inflammation may play an important role in this increased risk. More studies are needed to further elucidate the extent of non-coronary CVD in PLWH and the underlying mechanisms for them.

Relationship Between HIV Infection, Antiretroviral Therapy, Inflammatory Markers, and Cerebrovascular Endothelial Function Among Adults in Urban China

BACKGROUND

Cerebrovascular risk is increased in people living with HIV infection compared with age-matched uninfected individuals. Cerebrovascular endothelial dysfunction related to antiretroviral therapy (ART) and inflammation may contribute to higher stroke risk in HIV infection.

METHODS

We compared cerebral vasoreactivity-a measure of cerebrovascular endothelial function assessed by the breath-holding index (BHI) using transcranial Doppler ultrasound-between virologically suppressed Chinese HIV-infected individuals followed in an HIV clinic in Beijing, China, and uninfected controls. We constructed mixed-effects models to evaluate the association of HIV, ART, and inflammatory markers with cerebral vasoreactivity.

RESULTS

In an unadjusted model, HIV infection was associated with a trend toward lower cerebral vasoreactivity (BHI 1.08 versus 1.26, P = 0.079). In multivariable analyses, cholesterol modified the association between HIV infection and cerebral vasoreactivity (P = 0.015 for interaction). At a lower total cholesterol of 4.15 mmol/L, HIV was associated with lower cerebral vasoreactivity (BHI -0.28, P = 0.019), whereas at a cholesterol of 5.15 mmol/L, the reduction in cerebral vasoreactivity associated with HIV was no longer statistically significant (BHI -0.05, P = 0.64). Among HIV-infected individuals, use of lopinavir/ritonavir compared with efavirenz was associated with lower cerebral vasoreactivity (BHI -0.24, P = 0.040). We did not find a significant association between inflammatory markers and cerebral vasoreactivity.

CONCLUSIONS

Cerebrovascular endothelial dysfunction associated with HIV infection may be most relevant for individuals with less traditional vascular risk, such as those with lower cholesterol. Further study of the impact of ART on cerebrovascular endothelial function is warranted to aid with ART selection in individuals at high cerebrovascular risk.

Clinical characteristics and outcomes of patients with stroke admitted to three tertiary hospitals in Zimbabwe: A retrospective one-year study

BACKGROUND

Epidemiological data on stroke in Zimbabwe are scarce and few clinical studies have been performed to date.

METHODS

A retrospective review of the medical records of patients admitted for stroke during the year 2012 was performed at three tertiary hospitals. Sociodemographic data were recorded alongside with comorbidities and outcomes. Scoping over a period of one year using records of patients admitted for stroke helped to quantify and qualify the stroke problem. Descriptive analysis was done using STATA version 13.0.

RESULTS

A total of 450 stroke cases, (63% women) were included in the final analysis. The proportion of stroke cases among the admissions was 0.61%. Mean age of the stroke patients was 61.6±16.8 years (95% CI=60.1; 63.2). Risk factors were hypertension (58.5%), diabetes (18%) and HIV, (14%)). Diagnosis was clinical and 39.4% had a CT scan. Mean length of hospital stay was 8.1±5.6 days with a significance difference noted among hospitals (p<0.001). In-hospital mortality was 24.9%, 95% CI (20.9; 29.0%). Mortality was associated with place of admission (p<0.001). Gender and side of stroke were significantly associated (p<0.001).

CONCLUSIONS

The sociodemographic characteristics mirrored findings from elsewhere. Mean age was higher than reported for Zimbabwe in the nineties and lately for Malawi. Majority of patients were female, elderly and hypertensive in line with findings from other countries. Presence of HIV is supported by recent studies from Malawi and South Africa. The relationship between gender and side affected needs further research. There is need to standardise acute care through proper diagnosis to reduce mortality. There is need to support caregivers post-discharge. Data-handling is poor and there is limited capacity for Sub Saharan Africa hospitals to provide optimal stroke care. This may have long term implications on the outcome of survivors and caregivers. There is need of vigilance in acute stroke care.

HIV infection, hypercoagulability and ischaemic stroke in adults at the University Teaching Hospital in Zambia: a case control study

BACKGROUND

In Zambia, 14.2% of adults have HIV/AIDS. There has been a substantial and significant increase in patients hospitalized for ischaemic stroke with co-existing HIV infection. However, little is known about the mechanism of stroke in these HIV + ve patients let alone studied in our region. The aim of this pilot study was to explore the association of hypercoagulability state in HIV + ve patients with ischaemic stroke. This was achieved by comparing hypercoagulability state markers between HIV + ve ischaemic stroke patients with HIV-ve and HIV + ve patients with and without ischaemic stroke respectively.

METHODS

A matched case control study in which a total of 52 HIV + ve patients with ischaemic stroke were prospectively compared with control groups for the presence of protein S, protein C deficiencies and hyperhomocysteinaemia. The control groups comprised an equal number of consecutively matched for age and sex HIV-ve and HIV + ve patients with and without ischaemic stroke respectively. Data was analysed in contingency tables using Paired t- test, Chi square and conditional logistic regression.

RESULTS

Ischaemic stroke of undetermined aetiology occurred more frequently in HIV + ve compared to HIV-ve patients (p < 0.001). In addition, protein S deficiency and Hyperhomocysteinaemia were more prominent in HIV + ve than HIV-ve ischaemic stroke patients (P = 0.011). There was no difference in the presence of hyperhomocysteinaemia or protein S deficiency in HIV + ve patients with or without ischaemic stroke. Protein C deficiency was not noted to be significantly different between the cases and the two control arms.

CONCLUSION

Protein S deficiency and hyperhomocysteinaemia were associated with HIV infection, but not stroke in our study population. However, this is an area that requires extensive research and one that we cannot afford to ignore as it is an important bridge to all cardiovascular and cerebrovascular diseases.

Cardiovascular disease risk prediction by the American College of Cardiology (ACC)/American Heart Association (AHA) Atherosclerotic Cardiovascular Disease (ASCVD) risk score among HIV-infected patients in sub-Saharan Africa

OBJECTIVES

HIV-infected patients are at increased risk for cardiovascular disease (CVD). However, general population CVD risk prediction equations that identify HIV-infected patients at elevated risk have not been widely assessed in sub-Saharan African (SSA).

METHODS

HIV-infected adults from 30-50 years of age with documented viral suppression were enrolled into a cross-sectional study in Gaborone, Botswana. Participants were screened for CVD risk factors. Bilateral carotid intima-media thickness (cIMT) was measured and 10-year predicted risk of cardiovascular disease was calculated using the Pooled Cohorts Equation for atherosclerotic CVD (ASCVD) and the 2008 Framingham Risk Score (FRS) (National Cholesterol Education Program III-NCEP III). ASCVD ≥7.5%, FRS ≥10%, and cIMT≥75th percentile were considered elevated risk for CVD. Agreement in classification of participants as high-risk for CVD by cIMT and FRS or ASCVD risk score was assessed using McNemar`s Test. The optimal cIMT cut off-point that matched ASCVD predicted risk of ≥7.5% was assessed using Youden's J index.

RESULTS

Among 208 HIV-infected patients (female: 55%, mean age 38 years), 78 (38%) met criteria for ASCVD calculation versus 130 (62%) who did not meet the criteria. ASCVD classified more participants as having elevated CVD risk than FRS (14.1% versus 2.6%, McNemar's exact test p = 0.01), while also classifying similar proportion of participants as having elevated CVD like cIMT (14.1% versus 19.2%, McNemar's exact test p = 0.34). Youden's J calculated the optimal cut point at the 81st percentile for cIMT to correspond to an ASCVD score ≥7.5% (sensitivity = 72.7% and specificity = 88.1% with area under the curve for the receiver operating characteristic [AUC] of 0.82, 95% Mann-Whitney CI: 0.66-0.99).

CONCLUSION

While the ASCVD risk score classified more patients at elevated CVD risk than FRS, ASCVD score classified similar proportion of patients as high risk when compared with established subclinical atherosclerosis. However, potential CVD risk category misclassification by established equations such as ASCVD may still exist among HIV-infected patients; hence there is still a need for development of a CVD risk prediction equation tailored to HIV-infected patients in SSA.

Antiretroviral therapy related adverse effects: Can sub-Saharan Africa cope with the new "test and treat" policy of the World Health Organization?

BACKGROUND

Recent studies have shown that early antiretroviral therapy (ART) initiation results in significant HIV transmission reduction. This is the rationale behind the "test and treat" policy of the World Health Organization (WHO). Implementation of this policy will lead to an increased incidence of ART-related adverse effects, especially in sub-Saharan Africa (SSA). Is the region yet ready to cope with such a challenging issue?

MAIN BODY

The introduction and widespread use of ART have drastically changed the natural history of HIV/AIDS, but exposure to ART leads to serious medication-related adverse effects mainly explained by mitochondrial toxicities, and the situation will get worse in the near future. Indeed, ART is associated with an increased risk of developing cardiovascular disease, lipodystrophy, prediabetes and overt diabetes, insulin resistance and hyperlactatemia/lactic acidosis. The prevalence of these disorders is already high in SSA, and the situation will be exacerbated by the implementation of the new WHO recommendations. Most SSA countries are characterized by (extreme) poverty, very weak health systems, inadequate and low quality of health services, inaccessibility to existing health facilities, lack of (qualified) health personnel, lack of adequate equipment, inaccessibility and unaffordability of medicines, and heavy workload in a context of a double burden of disease. Additionally, there is dearth of data on the incidence and predictive factors of ART-related adverse effects in SSA, to anticipate on strategies that should be put in place to prevent the occurrence of these conditions or properly estimate the upcoming burden and prepare an adequate response plan. These are required if we are to anticipate and effectively prevent this upcoming burden.

CONCLUSION

While SSA would be the first region to experience the huge benefits of implementing the "test and treat" policy of the WHO, the region is not yet prepared to manage the consequential increased burden of ART-related toxic and metabolic complications. Urgent measures should be taken to fill the lacunae if SSA is not to become over-burdened by the consequences of the "test and treat" policy.

A new look at human immunodeficiency virus infection and stroke in Sub-Saharan Africa

Stroke and human immunodeficiency virus (HIV) infection are major causes of morbidity and mortality in Sub-Saharan Africa (SSA), with disease burdens being amongst the highest worldwide. HIV infection has emerged as an important risk factor for stroke. The remarkable development in the treatment of HIV infection which occurred in recent decades has allowed the survival of a large number of patients. This therapeutic success which allows patients to live longer has facilitated the emergence of a new population of adults with increased risk for cardiovascular disease including stroke due to aging, the direct effects of HIV infection and combined anti-retroviral therapy (cART). Preventive strategies to decrease the burden of stroke amongst this specific patient population remain understudied in this region of the world. Lack of early diagnosis (CT scans) and poor record keeping make appreciation of the burden difficult. There is indisputable evidence that early diagnosis and early placement on cART therapy reduce HIV associated morbidity and mortality in this region of the world. However, the emergence of a new population of patients at risk for developing stroke (HIV patients) who fortunately live longer deserves a keener attention. Long term effects of cART regimens on cardiovascular and metabolic profiles remain uncertain, and specific cohort studies to properly ascertain its consequences are needed. The evidence and specific guidelines with regards to anti-platelet therapies and statin use, though potentially beneficial, in this patient sub group remains scarce. African specific cohort studies including HIV positive patients in our opinion should constitute a top research priority, to properly ascertain the potential roles of anti-platelet therapies and statins with regards to primary and secondary prevention of stroke, as well as long term effects of cART on their cardiovascular and metabolic profiles.

Arterial ischemic stroke in HIV: Defining and classifying etiology for research studies

HIV infection, and potentially its treatment, increases the risk of an arterial ischemic stroke. Multiple etiologies and lack of clear case definitions inhibit progress in this field. Several etiologies, many treatable, are relevant to HIV-related stroke. To fully understand the mechanisms and the terminology used, a robust classification algorithm to help ascribe the various etiologies is needed. This consensus paper considers the strengths and limitations of current case definitions in the context of HIV infection. The case definitions for the major etiologies in HIV-related strokes were refined (e.g., varicella zoster vasculopathy and antiphospholipid syndrome) and in some instances new case definitions were described (e.g., HIV-associated vasculopathy). These case definitions provided a framework for an algorithm to help assign a final diagnosis, and help classify the subtypes of HIV etiology in ischemic stroke.