Impact of body fat changes in mediating the effects of antiretroviral therapy on blood pressure in HIV-infected persons in a sub-Saharan African setting

Background:Previous studies of HIV-infected patients have shown significant associations between highly active antiretroviral therapy(HAART)and increased blood pressure;however,the mechanisms involved are less clear.Therefore,we sought to investigate the potential impact of body fat changes in mediating the effects of HAART on blood pressure changes among people living with HIV.Methods:Four hundred six consenting patients(≥18 years of age)attending a tertiary HIV clinic in semi-urban Nigeria were recruited between August and November 2014 as part of a cross-sectional study.We performed bias-corrected bootstrap tests of mediation using 95%confidence intervals(CI)to determine the mediating effects of body mass index and waist circumference(mediators)on the total effects of HAART exposure(primary predictor)on blood pressure(outcome),while controlling for age,sex and other potential confounders.Results:Waist circumference remained a significant partial mediator of the total effects of HAART exposure on increasing systolic blood pressure(coefficient:1.01,95%CI:0.33 to 2.52,11%mediated)and diastolic blood pressure(coefficient:0.68,95%CI:0.26 to 1.89,9%mediated)after adjusting for age,sex,smoking status,CD4 count and duration of HIV infection.No significant mediating effect was observed with body mass index alone or in combination with waist circumference after adjusting for all potential confounders.Conclusion:Waist circumference significantly mediates the effects of HAART on blood pressure in persons living with HIV,independent of the role of traditional risk factors.The use of waist circumference as a complementary body fat measure to body mass index may improve the clinical prediction of hypertension in HIV-infected patients on antiretroviral therapy.

Co-morbidity of malnutrition with falciparum malaria parasitaemia among children under the aged 6-59 months in Somalia:a geostatistical analysis

Background:Malnutrition and malaria are both significant causes of morbidity and mortality in African children.However,the extent of their spatial comorbidity remains unexplored and an understanding of their spatial correlation structure would inform improvement of integrated interventions.We aimed to determine the spatial correlation between both wasting and low mid upper arm circumference(MUAC)and falciparum malaria among Somalian children aged 6-59 months.Methods:Data were from 49227 children living in 888 villages between 2007 to 2010.We developed a Bayesian geostatistical shared component model in order to determine the common spatial distributions of wasting and falciparum malaria;and low-MUAC and falciparum malaria at 1×1 km spatial resolution.Results:The empirical correlations with malaria were 0.16 and 0.23 for wasting and low-MUAC respectively.Shared spatial residual effects were statistically significant for both wasting and low-MUAC.The posterior spatial relative risk was highest for low-MUAC and malaria(range:0.19 to 5.40)and relatively lower between wasting and malaria(range:0.11 to 3.55).Hotspots for both wasting and low-MUAC with malaria occurred in the South Central region in Somalia.Conclusions:The findings demonstrate a relationship between nutritional status and falciparum malaria parasitaemia,and support the use of the relatively simpler MUAC measurement in surveys.Shared spatial distribution and distinct hotspots present opportunities for targeted seasonal chemoprophylaxis and other forms of malaria prevention integrated within nutrition programmes.