title: The epidemiology of chronic kidney disease in Northern Tanzania: a population-based survey.
abstract: BACKGROUND
  In sub-Saharan Africa, kidney failure has a high morbidity and mortality. Despite this, population-based estimates of prevalence, potential etiologies, and awareness are not available.
  
  
  METHODS
  Between January and June 2014, we conducted a household survey of randomly-selected adults in Northern Tanzania. To estimate prevalence we screened for CKD, which was defined as an estimated glomerular filtration rate ≤ 60 ml/min/1.73m2 and/or persistent albuminuria. We also screened for human immunodeficiency virus (HIV), diabetes, hypertension, obesity, and lifestyle practices including alcohol, tobacco, and traditional medicine use. Awareness was defined as a self-reported disease history and subsequently testing positive. We used population-based age- and gender-weights in estimating prevalence, and we used generalized linear models to explore potential risk factors associated with CKD, including living in an urban environment.
  
  
  RESULTS
  We enrolled 481 adults from 346 households with a median age of 45 years. The community-based prevalence of CKD was 7.0% (95% CI 3.8-12.3), and awareness was low at 10.5% (4.7-22.0). The urban prevalence of CKD was 15.2% (9.6-23.3) while the rural prevalence was 2.0% (0.5-6.9). Half of the cases of CKD (49.1%) were not associated with any of the measured risk factors of hypertension, diabetes, or HIV. Living in an urban environment had the strongest crude (5.40; 95% CI 2.05-14.2) and adjusted prevalence risk ratio (4.80; 1.70-13.6) for CKD, and the majority (79%) of this increased risk was not explained by demographics, traditional medicine use, socioeconomic status, or co-morbid non-communicable diseases (NCDs).
  
  
  CONCLUSIONS
  We observed a high burden of CKD in Northern Tanzania that was associated with low awareness. Although demographic, lifestyle practices including traditional medicine use, socioeconomic factors, and NCDs accounted for some of the excess CKD risk observed with urban residence, much of the increased urban prevalence remained unexplained and will further study as demographic shifts reshape sub-Saharan Africa.
authors.affiliation: Department of Medicine, Duke University, Durham, North Carolina, United States of America; Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America.
authors.forename: John W
authors.initials: JW
authors.lastname: Stanifer
authors.affiliation: Kilimanjaro Christian Medical College, Moshi, Tanzania.
authors.forename: Venance
authors.initials: V
authors.lastname: Maro
authors.affiliation: Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America.
authors.forename: Joseph
authors.initials: J
authors.lastname: Egger
authors.affiliation: Kilimanjaro Christian Medical College, Moshi, Tanzania.
authors.forename: Francis
authors.initials: F
authors.lastname: Karia
authors.affiliation: Department of Medicine, Duke University, Durham, North Carolina, United States of America; Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America.
authors.forename: Nathan
authors.initials: N
authors.lastname: Thielman
authors.affiliation: Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America; Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, United States of America.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Turner
authors.affiliation: Kilimanjaro Christian Medical College, Moshi, Tanzania.
authors.forename: Dionis
authors.initials: D
authors.lastname: Shimbi
authors.affiliation: Kilimanjaro Christian Medical College, Moshi, Tanzania.
authors.forename: Humphrey
authors.initials: H
authors.lastname: Kilaweh
authors.affiliation: Kilimanjaro Christian Medical College, Moshi, Tanzania.
authors.forename: Oliver
authors.initials: O
authors.lastname: Matemu
authors.affiliation: Department of Medicine, Duke University, Durham, North Carolina, United States of America; Duke Clinical Research Institute, Duke University, Durham, North Carolina, United States of America.
authors.forename: Uptal D
authors.initials: UD
authors.lastname: Patel
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D011795:Surveys and Questionnaires; D013636:Tanzania / Q000453:epidemiology; D055815:Young Adult