Monitoring diabetes in patients with and without rheumatoid arthritis: a Medicare study
1 Department of Medicine, Rheumatology Section, University of Wisconsin School of Medicine and Public Health, 600 N. Highland Ave., Madison, WI 53792, USA
2 Departments of Medicine and Dermatology, University of Wisconsin School of Medicine and Public Health, 600 N. Highland Ave., Madison, WI 53792, USA
3 Health Services Research and Development, Veterans Affairs Pittsburgh Healthcare System, University Drive, Pittsburgh, PA 15240, USA
4 Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, 1140 Salk Hall, 3501 Terrace St., Pittsburgh, PA 15261, USA
5 Department of Medicine, Geriatrics Division, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave., Madison, WI 53792, USA
6 William S. Middleton Hospital, Geriatric Research Education and Clinical Center, United States Department of Veterans Affairs, 2500 Overlook Terrace, Madison, WI 53705, USA
7 Department of Family Medicine, University of Wisconsin School of Medicine and Public Health, 1100 Delaplaine Ct., Madison, WI 53715, USA
8 Department of Population Health Sciences, University of Wisconsin School of Medicine and Public Health, 707 WARF Building, 610 North Walnut St., Madison, WI 53726, USA
9 Department of Surgery, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave., Madison, WI 53792, USA
Arthritis Research & Therapy 2012, 14:R166 doi:10.1186/ar3915Published: 18 July 2012
Diabetes mellitus is a key predictor of mortality in rheumatoid arthritis (RA) patients. Both RA and diabetes increase the risk of cardiovascular disease (CVD), yet understanding of how comorbid RA impacts the receipt of guideline-based diabetes care is limited. The purpose of this study was to examine how the presence of RA affected hemoglobin A1C (A1c) and lipid measurement in older adults with diabetes.
Using a retrospective cohort approach, we identified beneficiaries ≥65 years old with diabetes from a 5% random national sample of 2004 to 2005 Medicare patients (N = 256,331), then examined whether these patients had comorbid RA and whether they received guideline recommended A1c and lipid testing in 2006. Multivariate logistic regression was used to examine the effect of RA on receiving guideline recommended testing, adjusting for baseline sociodemographics, comorbidities and health care utilization.
Two percent of diabetes patients had comorbid RA (N = 5,572). Diabetes patients with comorbid RA were more likely than those without RA to have baseline cardiovascular disease (such as 17% more congestive heart failure), diabetes-related complications including kidney disease (19% higher), lower extremity ulcers (77% higher) and peripheral vascular disease (32% higher). In adjusted models, diabetes patients with RA were less likely to receive recommended A1c testing (odds ratio (OR) 0.84, CI 0.80 to 0.89) than those without RA, but were slightly more likely to receive lipid testing (OR 1.08, CI 1.01 to 1.16).
In older adults with diabetes, the presence of comorbid RA predicted lower rates of A1c testing but slightly improved lipid testing. Future research should examine strategies to improve A1c testing in patients with diabetes and RA, in light of increased CVD and microvascular risks in patients with both conditions.