Pathophysiology of the HIV-Associated Lipodystrophy Syndrome

Inflammatory biomarkers and soft tissue changes among patients commencing second-line antiretroviral therapy after first-line virological failure

INTRODUCTION

We explored associations of inflammatory and immune activation biomarkers at baseline and percentage gain in peripheral and trunk fat and lean mass over 96 weeks in patients with confirmed virological failure initiating lopinavir-anchored second-line antiretroviral therapy (ART) regimens.

METHOD

We measured baseline plasma concentration of interleukin (IL)-6, tumour necrosis factor (TNF), neopterin, IL-6, high-sensitivity C-reactive protein (hs-CRP), D-dimer, soluble cluster of differentiation 14 (sCD14), and soluble CD163 in 123 participants of the SECOND-LINE body composition substudy. Linear regression assessed the association between biomarkers and percentage gain in limb/trunk fat and lean mass, adjusting for age, nucleoside or nucleotide reverse transcriptase inhibitor (N(t)RTI) use, body mass index, ethnicity, smoking, viral load, CD4+ T-cell counts, smoking, duration of ART use, and cholesterol.

RESULTS

Mean (standard deviation) age was 38 (7.3) years, CD4+ T-cell count was 252 (185.9) cells/μl, human immunodeficiency virus viral load was 4.2 (0.9) log10 copies/ml, 47% (58/123) were in the N(t)RTI arm (vs. raltegravir [RAL] arm in 53%); 56.1% (69/123) were females. In adjusted analyses, for every log10 increase in baseline levels of IL-6, neopterin, and D-dimer, the percentage gain in peripheral fat over 96 weeks was 11.8% (95% confidence interval [CI]: 0.9-22.6, P = 0.033); neopterin, 11.2% (95% CI: 3.2-19.2, P = 0.007); D-dimer 9.6% (95% CI: 3.1-15.9, P = 0.004), respectively. The associations remained significant when analysis was stratified by N(t)RTI vs. RAL and included only patients with viral suppression at week 48. A significant gradient in lean mass gain was seen across quartiles of IL-6, TNF, neopterin, hsCRP, D-dimer, and sCD14.

CONCLUSION

Inflammatory biomarkers provide important mechanistic insights into the pathogenesis of limb fat and lean mass changes independently of ART.

Treatment outcomes in multidrug resistant tuberculosis-human immunodeficiency virus Co-infected patients on anti-retroviral therapy at Sizwe Tropical Disease Hospital Johannesburg, South Africa

BACKGROUND

Multidrug resistant-tuberculosis (MDR-TB) is a threat to global tuberculosis control which is worsened by human immune-deficiency virus (HIV) co-infection. There is however paucity of data on the effects of antiretroviral treatment (ART) before or after starting MDR-TB treatment. This study determined predictors of mortality and treatment failure among HIV co-infected MDR-TB patients on ART.

METHODS

A retrospective medical record review of 1200 HIV co-infected MDR-TB patients admitted at Sizwe Tropical Disease Hospital, Johannesburg from 2007 to 2010 was performed. Chi-square test was used to determine treatment outcomes in HIV co-infected MDR-TB patients on ART. Multivariable logistic regression and Poisson models were used to determine predictors of mortality and treatment failure respectively.

RESULTS

Mortality was higher (21.8% vs. 15.4%) among patients who started ART before initiating MDR-TB treatment compared with patients initiated on ART after commencing MDR-TB treatment (p = 0.013). Factors significantly associated with mortality included: the use of ART before starting MDR-TB treatment (OR 1.65, 95% CI 1.02-2.73), severely-underweight (OR 3.71, 95% CI 1.89-7.29) and underweight (OR 2.35, 95% CI 1.30-4.26), cavities on chest x-rays at baseline (OR 1.76, 95% CI 1.08-2.94), presence of other opportunistic infections (OR 1.80, 95% CI 1.10-2.94) and presence of other co-morbidities (OR 2.26, 95% CI 1.20-4.21). Factors predicting failure were severe anaemia (IRR (OR 4.72, 95% CI 1.47-15), other co-morbidities (OR 2.39, 95% CI 1.05-5.43) and modified individualised regimen at baseline (OR 2.15, 95% CI 0.98-4.71).

CONCLUSIONS

High mortality among patients already on ART before initiating MDR-TB treatment is a worrisome development. Management of adverse-events, opportunistic infections and co-morbidities in these patients is important if the protective benefits of being on ART are to be maximized. There is the need to intensify intervention programmes targeted at early identification of MDR-TB, treatment initiation, drug monitoring and increasing adherence among HIV co-infected MDR-TB patients.

High prevalence and impact on the quality of life of facial lipoatrophy and other abnormalities in fat tissue distribution in HIV-infected patients treated with antiretroviral therapy

Few data report the prevalence in actual clinical settings of lipodystrophy (LD), and in particular of facial lipoatrophy (LA), in HIV-infected patients treated with long-term antiretroviral therapy (ART). A French, multicenter, cross-sectional, observational study was conducted in HIV-infected patients on continuous ART for more than 12 months. The main objective was to assess the prevalence of facial LA in this population. Additional objectives were to make the same assessments for nonfacial LA and lipohypertrophy. The presence of LD signs, type, and severity was assessed by clinicians and compared with patient self-evaluations through two questionnaires. A total of 2,131 assessable patients had a median age of 46 years and a median time on ART of 10 years. Physicians diagnosed facial LA in 54% of patients and these subjects had received ART for a longer duration than those without LA. Thymidine analog usage was associated with an increased likelihood of facial LA, but 28% of patients recently treatment-initiated (1-5 years) were also affected. At other sites, LA and lipohypertrophy were diagnosed in 59% and 57% of cases, respectively. The concordance between physician and patient assessments was good for facial and buttocks LA. In this study, facial LA affects more than half of the subjects and is frequent even among the most recently treated patients. The prevalence of facial LA significantly increases with the duration of ART, with male gender, hepatitis C virus (HCV) coinfection, and non-African origin being independent risk factors. Lipohypertrophy is frequent and appears early after ART initiation.

A review of co-morbidity between infectious and chronic disease in Sub Saharan Africa: TB and diabetes mellitus, HIV and metabolic syndrome, and the impact of globalization

Background

Africa is facing a rapidly growing chronic non-communicable disease burden whilst at the same time experiencing continual high rates of infectious disease. It is well known that some infections increase the risk of certain chronic diseases and the converse. With an increasing dual burden of disease in Sub Saharan Africa the associations between diseases and our understanding of them will become of increased public health importance.

Aims

In this review we explore the relationships reported between tuberculosis and diabetes mellitus, human immunodeficiency virus, its treatment and metabolic risk. We aimed to address the important issues surrounding these associations within a Sub Saharan African setting and to describe the impact of globalization upon them.

Findings

Diabetes has been associated with a 3-fold incident risk of tuberculosis and it is hypothesised that tuberculosis may also increase the risk of developing diabetes. During co-morbid presentation of tuberculosis and diabetes both tuberculosis and diabetes outcomes are reported to worsen. Antiretroviral therapy for HIV has been associated with an increased risk of developing metabolic syndrome and HIV has been linked with an increased risk of developing both diabetes and cardiovascular disease. Globalization is clearly related to an increased risk of diabetes and cardiovascular disease. It may be exerting other negative and positive impacts upon infectious and chronic non-communicable disease associations but at present reporting upon these is sparse.

Conclusion

The impact of these co-morbidities in Sub Saharan Africa is likely to be large. An increasing prevalence of diabetes may hinder efforts at tuberculosis control, increasing the number of susceptible individuals in populations where tuberculosis is endemic, and making successful treatment harder. Roll out of anti-retroviral treatment coverage within Sub Saharan Africa is an essential response to the HIV epidemic however it is likely to lead to a growing number of individuals suffering adverse metabolic consequences. One of the impacts of globalization is to create environments that increase both diabetes and cardiovascular risk but further work is needed to elucidate other potential impacts. Research is also needed to develop effective approaches to reducing the frequency and health impact of the co-morbidities described here.