title: A Decade Analysis of Trends and Outcomes of Male vs Female Patients Who Underwent Bariatric Surgery.
abstract: BACKGROUND
  Male obesity rates are now estimated to be equal to female obesity rates. Despite this, men constitute a minority of patients undergoing bariatric surgery. The aim of this study was to examine the national trends and outcomes of bariatric surgery in male patients compared with female patients.
  
  
  METHODS
  The Nationwide Inpatient Sample database was reviewed for obese patients undergoing bariatric surgery between 2002 and 2011. Outcomes were analyzed according to sex. Main outcomes measures were patient demographics, length of stay, risk-adjusted inpatient morbidity and mortality, and hospital charge.
  
  
  RESULTS
  During the 10-year period, 810,999 patients underwent bariatric surgery; 19.3% were male and 80.7% were female. The percentage of male patients increased from 15.4% in 2002 to 21.7% in 2011. Mean age was significantly older for males (46 ± 11 years vs 43 ± 11 years; p < 0.01, respectively). Male patients had a higher proportion of moderate, major, and extreme severity of illness classifications and higher rates of comorbid conditions. Serious morbidity was significantly higher in male patients compared with female patients (7.58% vs 5.42%; p < 0.01). Mean hospital length of stay was longer for male patients (2.75 vs 2.61 days; p < 0.01) with a higher mean hospital charge ($38,682 vs $34,294; p < 0.01). Compared with the female group, the male group had higher risk-adjusted in-hospital mortality (odds ratio = 2.16; 95% CI, 1.62-2.88; p < 0.01) and serious morbidity (odds ratio = 1.23; 95% CI, 1.17-1.29; p < 0.01).
  
  
  CONCLUSIONS
  The number of male patients undergoing bariatric surgery in the past decade continues to be a small fraction compared with the number of female patients. Men undergoing bariatric surgery tend to have higher severity of illness, with higher risk-adjusted serious morbidity and mortality rates. Additional studies are necessary to examine barriers in obtaining treatment for obese men.
authors.affiliation: Department of Surgery, University of California, Irvine School of Medicine, Orange, CA.
authors.forename: Monica T
authors.initials: MT
authors.lastname: Young
authors.affiliation: Department of Statistics, University of California, Irvine, Irvine, CA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Phelan
authors.affiliation: Department of Surgery, University of California, Irvine School of Medicine, Orange, CA. Electronic address: ninhn@uci.edu.
authors.forename: Ninh T
authors.initials: NT
authors.lastname: Nguyen
mesh_terms: D000328:Adult; D050110:Bariatric Surgery / Q000401:mortality / Q000706:statistics & numerical data / Q000639:trends*; D016208:Databases, Factual; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data / Q000639:trends; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D017678:Sex Distribution; D012737:Sex Factors; D016896:Treatment Outcome; D014481:United States