title: Health care use during 20 years following bariatric surgery.
abstract: BACKGROUND
  Bariatric surgery results in sustained weight loss; reduced incidence of diabetes, cardiovascular events, and cancer; and improved survival. The long-term effect on health care use is unknown.
  
  
  OBJECTIVE
  To assess health care use over 20 years by obese patients treated conventionally or with bariatric surgery.
  
  
  METHODS
  The Swedish Obese Subjects study is an ongoing, prospective, nonrandomized, controlled intervention study conducted in the Swedish health care system that included 2010 adults who underwent bariatric surgery and 2037 contemporaneously matched controls recruited between 1987 and 2001. Inclusion criteria were age 37 years to 60 years and body mass index of 34 or higher in men and 38 or higher in women. Exclusion criteria were identical in both groups.
  
  
  METHODS
  Of the surgery patients, 13% underwent gastric bypass, 19% gastric banding, and 68% vertical-banded gastroplasty. Controls received conventional obesity treatment.
  
  
  METHODS
  Annual hospital days (follow-up years 1 to 20; data capture 1987-2009; median follow-up 15 years) and nonprimary care outpatient visits (years 2-20; data capture 2001-2009; median follow-up 9 years) were retrieved from the National Patient Register, and drug costs from the Prescribed Drug Register (years 7-20; data capture 2005-2011; median follow-up 6 years). Registry linkage was complete for more than 99% of patients (4044 of 4047). Mean differences were adjusted for baseline age, sex, smoking, diabetes status, body mass index, inclusion period, and (for the inpatient care analysis) hospital days the year before the index date.
  
  
  RESULTS
  In the 20 years following their bariatric procedure, surgery patients used a total of 54 mean cumulative hospital days compared with 40 used by those in the control group (adjusted difference, 15; 95% CI, 2-27; P = .03). During the years 2 through 6, surgery patients had an accumulated annual mean of 1.7 hospital days vs 1.2 days among control patients (adjusted difference, 0.5; 95% CI, 0.2 to 0.7; P < .001). From year 7 to 20, both groups had a mean annual 1.8 hospital days (adjusted difference, 0.0; 95% CI, -0.3 to 0.3; P = .95). Surgery patients had a mean annual 1.3 nonprimary care outpatient visits during the years 2 through 6 vs 1.1 among the controls (adjusted difference, 0.3; 95% CI, 0.1 to 0.4; P = .003), but from year 7, the 2 groups did not differ (1.8 vs 1.9 mean annual visits; adjusted difference, -0.2; 95% CI, -0.4 to 0.1; P = .12). From year 7 to 20, the surgery group incurred a mean annual drug cost of US $930; the control patients, $1123 (adjusted difference, -$228; 95% CI, -$335 to -$121; P < .001).
  
  
  CONCLUSIONS
  Compared with controls, surgically treated patients used more inpatient and nonprimary outpatient care during the first 6-year period after undergoing bariatric surgery but not thereafter. Drug costs from years 7 through 20 were lower for surgery patients than for control patients.
  
  
  BACKGROUND
  clinicaltrials.gov Identifier: NCT01479452.
authors.affiliation: Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. martin.neovius@ki.se
authors.forename: Martin
authors.initials: M
authors.lastname: Neovius
authors.forename: Kristina
authors.initials: K
authors.lastname: Narbro
authors.forename: Catherine
authors.initials: C
authors.lastname: Keating
authors.forename: Markku
authors.initials: M
authors.lastname: Peltonen
authors.forename: Kajsa
authors.initials: K
authors.lastname: Sjöholm
authors.forename: Göran
authors.initials: G
authors.lastname: Agren
authors.forename: Lars
authors.initials: L
authors.lastname: Sjöström
authors.forename: Lena
authors.initials: L
authors.lastname: Carlsson
mesh_terms: D000328:Adult; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D050110:Bariatric Surgery; D016022:Case-Control Studies; D016527:Drug Costs / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006296:Health Services / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000191:economics / Q000601:surgery*; D013548:Sweden