title: Social and clinical attributes of patients who restart antiretroviral therapy in central and Copperbelt provinces, Zambia: a retrospective longitudinal study.
abstract: BACKGROUND
  About 30% of the patients initiated on antiretroviral therapy in Zambia default treatment. Some of these patients later restart treatment; however, the characteristics of these patients have not been well described and documented. The aim of this study was to describe and document the socio-demographic and clinical characteristics of patients who default and restart antiretroviral therapy, and to determine the socio-demographic characteristics associated with CD4 count response at 6 and 24 months of restarting antiretroviral therapy.
  
  
  METHODS
  A longitudinal retrospective analysis was performed on data from 535 adult patients restarting antiretroviral therapy in 2009 and 2010 at five antiretroviral therapy centres in Copperbelt and Central provinces of Zambia. To determine the association between the socio-demographic characteristics and CD4 cell count, quantile regression models were used.
  
  
  RESULTS
  Older age above 45 years was associated with a significantly lower CD4 cell response by 38.1 cells/mm(3) (95% Confidence interval [CI]: -109.4 to -0.2) compared to the younger age (15-29 years). Patients in formal employment (Adjusted Coefficient [AC] 29.5, 95% CI: 22.8 to 81.1) and self-employment (AC 48.1, 95% CI: 18.6 to 77.4) gained significantly higher CD4 cells than those unemployed. In addition, baseline CD4 count, type of treatment, WHO staging, total duration on treatment and duration lost to follow-up were found to be strong predictors of CD4 cell count at 6 and 24 months after restarting antiretroviral therapy treatment.
  
  
  CONCLUSIONS
  Age and occupation were the only socio-demographic characteristics predicting CD4 count in the patients at 6 months after restarting antiretroviral therapy after adjusting for other confounding clinical variables.
authors.affiliation: Department of Public Health, School of Medicine, University of Zambia, PO Box 50110, Lusaka, Zambia. cmulubwa@hotmail.com.
authors.forename: Chama
authors.initials: C
authors.lastname: Mulubwa
authors.affiliation: Department of Public Health, School of Medicine, University of Zambia, PO Box 50110, Lusaka, Zambia.
authors.forename: Oliver
authors.initials: O
authors.lastname: Mweemba
authors.affiliation: FHI 360, Plot 2374, Farmers Village, ZNFU Complex, Lusaka, Zambia.
authors.forename: Patrick
authors.initials: P
authors.lastname: Katayamoyo
authors.affiliation: Department of Public Health, School of Medicine, University of Zambia, PO Box 50110, Lusaka, Zambia.
authors.forename: Hikabasa
authors.initials: H
authors.lastname: Halwindi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008137:Longitudinal Studies; D059012:Lost to Follow-Up; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D009790:Occupations / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D055815:Young Adult; D015024:Zambia / Q000453:epidemiology
chemical_list: D019380:Anti-HIV Agents
keywords: Antiretroviral therapy; CD4 cell count; Defaulting; Lost to follow-up; Restart; Zambia