title: 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.
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK. C.U.Nduka@warwick.ac.uk.
authors.forename: Chidozie U
authors.initials: CU
authors.lastname: Nduka
authors.affiliation: Warwick-Centre for Applied Health Research and Delivery (WCAHRD), Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.|Centre for Applied Health Research and Delivery (CAHRD), Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.
authors.forename: Olalekan A
authors.initials: OA
authors.lastname: Uthman
authors.affiliation: Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Kimani
authors.affiliation: Department of Internal Medicine, Benue State University Teaching Hospital, Makurdi, Nigeria.
authors.forename: Abraham O
authors.initials: AO
authors.lastname: Malu
authors.affiliation: Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.|Epidemiology and Public Health Research Unit, Department of Population Health, Luxembourg Institute of Health, Strassen, L-1445, Luxembourg.
authors.forename: Saverio
authors.initials: S
authors.lastname: Stranges
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D001794:Blood Pressure / Q000187:drug effects*; D001823:Body Composition; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009549:Nigeria; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents
keywords: Blood pressure; Body mass index; HIV; Highly active antiretroviral therapy; Mediate; Waist circumference