Impact of bariatric surgery on health care costs of obese persons: a 6-year follow-up of surgical and comparison cohorts using health plan data.

IMPORTANCE: Bariatric surgery is a well-documented treatment for obesity, but there are uncertainties about the degree to which such surgery is associated with health care cost reductions that are sustained over time. OBJECTIVE: To provide a comprehensive, multiyear analysis of health care costs by type of procedure within a large cohort of privately insured persons who underwent bariatric surgery compared with a matched nonsurgical cohort. DESIGN: Longitudinal analysis of 2002-2008 claims data comparing a bariatric surgery cohort with a matched nonsurgical cohort. SETTING: Seven BlueCross BlueShield health insurance plans with a total enrollment of more than 18 million persons. PARTICIPANTS: A total of 29 820 plan members who underwent bariatric surgery between January 1, 2002, and December 31, 2008, and a 1:1 matched comparison group of persons not undergoing surgery but with diagnoses closely associated with obesity. MAIN OUTCOME MEASURES: Standardized costs (overall and by type of care) and adjusted ratios of the surgical group's costs relative to those of the comparison group. RESULTS: Total costs were greater in the bariatric surgery group during the second and third years following surgery but were similar in the later years. However, the bariatric group's prescription and office visit costs were lower and their inpatient costs were higher. Those undergoing laparoscopic surgery had lower costs in the first few years after surgery, but these differences did not persist. CONCLUSIONS AND RELEVANCE: Bariatric surgery does not reduce overall health care costs in the long term. Also, there is no evidence that any one type of surgery is more likely to reduce long-term health care costs. To assess the value of bariatric surgery, future studies should focus on the potential benefit of improved health and well-being of persons undergoing the procedure rather than on cost savings.

Spatial implications associated with using Euclidean distance measurements and geographic centroid imputation in health care research.

OBJECTIVE: To determine the effect of using Euclidean measurements and zip-code centroid geo-imputation versus more precise spatial analytical techniques in health care research. DATA SOURCES: Commercially insured members from a southeastern managed care organization. STUDY DESIGN: Distance from admitting inpatient facility to member's home and zip-code centroid (geographic placement) was compared using Euclidean straight-line and shortest-path drive distances (measurement technique). DATA COLLECTION: Administrative claims from October 2005 to September 2006. PRINCIPAL FINDINGS: Measurement technique had a greater impact on distance values compared with geographic placement. Drive distance from the geocoded address was highly correlated (r=0.99) with the Euclidean distance from the zip-code centroid. CONCLUSIONS: Actual differences were relatively small. Researchers without capabilities to produce drive distance measurements and/or address geocoding techniques could rely on simple linear regressions to estimate correction factors with a high degree of confidence.

Distal upper and lower limb fractures associated with thiazolidinedione use.

OBJECTIVE: To determine if patients with diabetes mellitus taking a thiazolidinedione experienced higher proportions of distal upper and lower limb fractures compared with those not taking a thiazolidinedione, as recent US Food and Drug Administration safety alerts suggested. STUDY DESIGN: This 3-year cross-sectional study used medical and pharmacy claims from a large southeastern managed care organization for continuously enrolled members from January 1, 2004, through December 31, 2006. METHODS: A total of 29,284 patients with type 2 diabetes mellitus aged 18 to 64 years were allocated to mutually exclusive study groups of thiazolidinedione users versus thiazolidinedione nonusers and thiazolidinedione type (pioglitazone hydrochloride, rosiglitazone maleate, or a combination). chi(2) Tests were used to determine if fracture proportions for thiazolidinedione users differed from those of thiazolidinedione nonusers and if thiazolidinedione type was significant. Multivariate logistic regression models and backward stepwise elimination algorithms were constructed to evaluate associations of fracture proportions with age, sex, and chronicity of drug use for 7462 members using a thiazolidinedione. RESULTS: The mean (SE) fracture proportions were significantly higher for thiazolidinedione users (5.1% [0.5%]) versus nonusers (4.5% [0.3%]) (P = .03). Fracture proportions did not differ by thiazolidinedione type (P = .86). Overall, women experienced a higher mean (SE) proportion of fractures compared with men (6.0% [0.4%] vs 3.5% [0.3%]) (P <.001), regardless of thiazolidinedione use. On average, the odds of experiencing a fracture for women using a thiazolidinedione increased 2% for every year increase in age. CONCLUSIONS: Patients with diabetes using thiazolidinediones, regardless of type, had higher proportions of distal upper and lower limb fractures compared with those not using thiazolidinediones. Fracture proportions were higher among women and increased with age.