title: Elderly veterans with dual eligibility for VA and Medicare services: where do they obtain a colonoscopy?
abstract: OBJECTIVE
  To examine the receipt of colonoscopy through the Veterans Health Administration (VA) or through Medicare by older veterans who are dually enrolled.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  The VA Outpatient Care Files and Medicare Enrollment Files were used to identify 1,060,523 patients 65 years and older in 15 of the 22 Veterans Integrated Service Networks nationally, who had 2 or more VA primary care visits in 2009 and who were simultaneously enrolled in Medicare. VA and Medicare files were used to identify the receipt of an outpatient colonoscopy. Patients were categorized as receiving care in community-based outpatient clinics (CBOCs) (n=601,337; 57%) or VA medical centers (n=459,186; 43%) based on where most patient-centered encounters occurred. Analyses used multinomial logistic regression to identify patient characteristics related to the odds of receiving a colonoscopy at the VA or through Medicare.
  
  
  RESULTS
  Patients had a mean age of 76.9 (SD=7.0) years; 98% were male, 89% were white, and 21% resided in a rural location. Overall, 100,060 (9.4%) patients underwent outpatient colonoscopy either through the VA (n=33,600; 35.5%) or Medicare providers (n=65,716; 65.5%). The adjusted odds of receiving a colonoscopy from Medicare providers were higher (P<.001) for patients who were male, white, receiving primary care at CBOCs, and for residents of an urban location. The receipt of colonoscopy through the VA decreased dramatically by age; for example, the odds of colonoscopy by the VA in patients aged >85 years and 80 to 84 years, relative to patients aged 65 to 69 years, were 0.26 and 0.13, respectively. In contrast, the receipt of colonoscopy through Medicare did not decline as markedly with age.
  
  
  CONCLUSIONS
  In a national analysis of the receipt of an outpatient colonoscopy by older veterans, more veterans received their colonoscopies through CMS than through the VA. The use of colonoscopy within the VA was found to be more concordant with age-related practice guidelines.
authors.affiliation: CADRE, Bldg 42, Iowa City VA Medical Center, 601 US Highway 6, Iowa City, IA 52246. E-mail: ashish.malhotra@va.gov.
authors.forename: Ashish
authors.initials: A
authors.lastname: Malhotra
authors.forename: Mary
authors.initials: M
authors.lastname: Vaughan-Sarrazin
authors.forename: Gary E
authors.initials: GE
authors.lastname: Rosenthal
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000554:Ambulatory Care Facilities / Q000706:statistics & numerical data*; D003113:Colonoscopy / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012737:Sex Factors; D012959:Socioeconomic Factors; D014481:United States; D014493:United States Department of Veterans Affairs / Q000706:statistics & numerical data*