title: Sustained effect of health insurance and facility quality improvement on blood pressure in adults with hypertension in Nigeria: A population-based study.
abstract: BACKGROUND
  Hypertension is a leading risk factor for death in sub-Saharan Africa. Quality treatment is often not available nor affordable. We assessed the effect of a voluntary health insurance program, including quality improvement of healthcare facilities, on blood pressure (BP) in hypertensive adults in rural Nigeria.
  
  
  METHODS
  We compared changes in outcomes from baseline (2009) to midline (2011) and endline (2013) between non-pregnant hypertensive adults in the insurance program area (PA) and a control area (CA), through household surveys. The primary outcome was the difference between the PA and CA in change in BP, using difference-in-differences analysis.
  
  
  RESULTS
  Of 1500 eligible households, 1450 (96.7%) participated, including 559 (20.8%) hypertensive individuals, of which 332 (59.4%) had follow-up data. Insurance coverage increased from 0% at baseline to 41.8% at endline in the PA and remained under 1% in the CA. The PA showed a 4.97 mm Hg (95% CI: -0.76 to +10.71 mm Hg) greater decrease in systolic BP and a 1.81 mm Hg (-1.06 to +4.68 mm Hg) greater decrease in diastolic BP from baseline to endline compared to the CA. Respondents with stage 2 hypertension showed an 11.43 mm Hg (95% CI: 1.62 to 21.23 mm Hg) greater reduction in systolic BP and 3.15 mm Hg (-1.22 to +7.53 mm Hg) greater reduction in diastolic BP in the PA compared to the CA. Attrition did not affect the results.
  
  
  CONCLUSIONS
  Access to improved quality healthcare through an insurance program in rural Nigeria was associated with a significant longer-term reduction in systolic BP in subjects with moderate or severe hypertension.
authors.affiliation: Department of Global Health, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands. Electronic address: m.hendriks@aighd.org.
authors.forename: Marleen E
authors.initials: ME
authors.lastname: Hendriks
authors.affiliation: Department of Global Health, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands.
authors.forename: Nicole T A
authors.initials: NT
authors.lastname: Rosendaal
authors.affiliation: Department of Global Health, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands.
authors.forename: Ferdinand W N M
authors.initials: FW
authors.lastname: Wit
authors.affiliation: Department of Epidemiology and Community Health, University of Ilorin Teaching Hospital, P.M.B. 1459, Ilorin 240001, Nigeria.
authors.forename: Oladimeji A
authors.initials: OA
authors.lastname: Bolarinwa
authors.affiliation: International Food Policy Research Institute, Markets, Trade and Institutions Division, 2033KSt, NW, Washington, DC 20006-1002, United States; Amsterdam Institute for International Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands.
authors.forename: Berber
authors.initials: B
authors.lastname: Kramer
authors.affiliation: Department of Global Health, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands.
authors.forename: Daniëlla
authors.initials: D
authors.lastname: Brals
authors.affiliation: Amsterdam Institute for International Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands; Brookings Institution, 1775 Massachusetts Ave, NW, Washington, DC 20036, Unites States.
authors.forename: Emily
authors.initials: E
authors.lastname: Gustafsson-Wright
authors.affiliation: Hygeia Nigeria Ltd, 13B Idejo Street, Victoria Island, Lagos, Nigeria.
authors.forename: Peju
authors.initials: P
authors.lastname: Adenusi
authors.affiliation: Departments of Internal and Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Meibergdreef 9, 1105 AZ, Amsterdam, the Netherlands.
authors.forename: Lizzy M
authors.initials: LM
authors.lastname: Brewster
authors.affiliation: Department of Epidemiology and Community Health, University of Ilorin Teaching Hospital, P.M.B. 1459, Ilorin 240001, Nigeria.
authors.forename: Gordon K
authors.initials: GK
authors.lastname: Osagbemi
authors.affiliation: Department of Epidemiology and Community Health, University of Ilorin Teaching Hospital, P.M.B. 1459, Ilorin 240001, Nigeria.
authors.forename: Tanimola M
authors.initials: TM
authors.lastname: Akande
authors.affiliation: Department of Global Health, Academic Medical Center, University of Amsterdam, Amsterdam Institute for Global Health and Development, Pietersbergweg 17, Amsterdam, 1105 BM, the Netherlands.
authors.forename: Constance
authors.initials: C
authors.lastname: Schultsz
mesh_terms: D000328:Adult; D017954:Africa South of the Sahara; D000368:Aged; D001795:Blood Pressure Determination / Q000191:economics / Q000379:methods; D005260:Female; D006297:Health Services Accessibility / Q000191:economics / Q000706:statistics & numerical data; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000191:economics / Q000453:epidemiology* / Q000401:mortality; D019458:Insurance Coverage / Q000191:economics / Q000706:statistics & numerical data*; D007348:Insurance, Health / Q000191:economics / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D009549:Nigeria / Q000453:epidemiology; D017063:Outcome Assessment, Health Care; D011247:Pregnancy; D058996:Quality Improvement; D011787:Quality of Health Care; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data
keywords: Access to care; Health insurance; Hypertension; Nigeria; Quality of care; Sub-Saharan Africa