Metabolic syndrome before and after initiation of antiretroviral therapy in treatment-naive HIV-infected individuals

Metabolic and body composition effects of newer antiretrovirals in HIV-infected patients

In the absence of a cure, HIV-infected patients are being successfully treated with antiretroviral therapies (ART) and living longer. Indeed, an increasing number of HIV-infected patients are living beyond the age of 50 years, and in that regard, the use of ART has transformed HIV into a chronic medical condition. As more HIV-infected patients are virologically controlled and living longer, the trajectory of disease morbidity has shifted, however, primarily from opportunistic infections and immune dysfunction to metabolic complications. Evidence suggests that HIV-infected patients acquire significant metabolic risks, including lipodystrophic changes, subclinical atherosclerosis, and insulin resistance. The etiology of these metabolic complications specifically in HIV-infected patients is not entirely clear but may be related to a complex interaction between long-term consequences of infection and HIV itself, chronic use of antiretrovirals, and underlying inflammatory processes. Previous classes of ART, such as protease inhibitors (PIs) and reverse transcriptase inhibitors, have been implicated in altering fat redistribution and lipid and glucose homeostasis. Advances in drug development have introduced newer ART with strategies to target novel mechanisms of action and improve patient adherence with multi-class drug combinations. In this review, we will focus on these newer classes of ART, including selected entry inhibitors, integrase inhibitors, and multi-class drug combinations, and two newer PIs, and the potential of these newer agents to cause metabolic complications in HIV-infected patients. Taken together, further reduction of morbidity in HIV-infected patients will require increasing awareness of the deleterious metabolic complications of ART with subsequent management to mitigate these risks.

HIV and aging: effects on the central nervous system

With the introduction of combination antiretroviral therapy, many human immunodeficiency virus-positive (HIV+) individuals are reaching advanced age. The proportion of people living with HIV older than 50 years already exceeds 50% in many communities, and is expected to reach this level nationally by 2015. HIV and aging are independently associated with neuropathological changes, but their concurrence may have a more deleterious effect on the central nervous system (CNS). Published data about neurocognitive and neuroimaging markers of HIV and aging are reviewed. Putative factors contributing to neurocognitive impairment and neuroimaging changes in the aging HIV+ brain, such as metabolic disturbances, cardiovascular risk factors, immune senescence, and neuroinflammation, are described. The possible relationship between HIV and some markers of Alzheimer's disease is presented. Current research findings emphasize multiple mechanisms related to HIV and combination antiretroviral therapy that compromise CNS structure and function with advancing age.

Metabolic syndrome

Metabolic syndrome is not a disease per se, but is a term that highlights traits that may have an increased risk of disease, approximately 2-fold for cardiovascular disease and 5-fold or more for type 2 diabetes mellitus. Obesity and insulin resistance are believed to be at the core of most cases of metabolic syndrome, although further research is required to truly understand the pathophysiology behind the syndrome and the gene-environment interactions that increase susceptibility. The mainstay of treatment remains lifestyle changes with exercise and diet to induce weight loss and pharmacologic intervention to treat atherogenic dyslipidemia, hypertension, and hyperglycemia.

Understanding and controlling chronic immune activation in the HIV-infected patients suppressed on combination antiretroviral therapy

Combination antiretroviral therapy (cART) has resulted in tremendous gains in survival among HIV-infected patients, but as a group those who achieve undetectable viral loads on cART experience a greater degree of immune activation and inflammation than the general population. HIV-infected patients continue to experience premature immune senescence with earlier and more frequent non-AIDS events compared to HIV-uninfected individuals. Chronic immune activation during suppressive cART derives from a variety of sources mediated by cytokines, chemokines, coagulation, microbial translocation, immune regulators and T(effector) cell activation abnormalities, among others. Current investigational strategies to control immune activation target potential causes of persistently heightened immune activation during cART such as microbial translocation, co-infections, and comorbidities or mediators along a common final pathway. Although several interventions have shown promise in vitro or in preliminary clinical trials, no intervention has sufficient evidence for routine use, making control of immune activation during cART an unmet need.

Diabetes and HIV: current understanding and future perspectives

Diabetes mellitus is a chronic disease with a higher risk of associated infections. HIV infection severely affects diabetic patients and acts as a significant health concern. Highly active antiretroviral therapy (HAART) has changed HIV from an acute infection to a chronic infection with associated significant metabolic abnormalities such as insulin resistance, impaired glucose tolerance, metabolic syndrome, diabetes, dyslipidemia, obesity, and lipodystrophy. These metabolic disturbances add complexity to the standards of care in HIV infection and further increase the risk for cardiovascular disease and renal complications. The co-association of diabetes and HIV needs to be managed appropriately to prevent mortality and morbidity and improve patient outcome. The current understanding of diabetes and other metabolic abnormalities along with management strategies in HIV infected patients are summarized in this article. The review also focuses on recent challenges in the diagnosis and management of co-existent diabetes and HIV infection.