Research Article Risk of Type 2 Diabetes among Osteoarthritis Patients in a Prospective Longitudinal Study M. Mushfiqur Rahman, 1,2 Jolanda Cibere, 3,4 Aslam H. Anis, 1,5 Charlie H. Goldsmith, 4,6 and Jacek A. Kopec 1,4 1 School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada V6T 1Z3 2 Department of Applied Statistics, East West University, Afabnagar, Dhaka 1212, Bangladesh 3 Department of Medicine, University of British Columbia, Vancouver, BC, Canada V5Z 1M9 4 Arthritis Research Centre of Canada, 5591 No. 3 Road, Richmond, BC, Canada V6X 2C7 5 Centre for Health Evaluation and Outcome Sciences, Vancouver, BC, Canada V6Z 1Y6 6 Health Sciences, Simon Fraser University, Burnaby, BC, Canada V5A 1S6 Correspondence should be addressed to M. Mushfqur Rahman; rahman102@gmail.com Received 10 July 2014; Accepted 7 October 2014; Published 4 November 2014 Academic Editor: Bruce M. Rothschild Copyright © 2014 M. Mushfqur Rahman et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objectives. Our aim was to determine the risk of diabetes among osteoarthritis (OA) cases in a prospective longitudinal study. Methods. Administrative health records of 577,601 randomly selected individuals from British Columbia, Canada, from 1991 to 2009, were analyzed. OA and diabetes cases were identifed by checking physician’s visits and hospital records. From 1991 to 1996 we documented 19,143 existing OA cases and selected one non-OA individual matched by age, sex, and year of administrative records. Poisson regression and Cox proportional hazards models were ftted to estimate the efects afer adjusting for available sociodemographic and medical factors. Results. At baseline, the mean age of OA cases was 61 years and 60.5% were women. Over 12 years of mean follow-up, the incidence rate (95% CI) of diabetes was 11.2 (10.90–11.50) per 1000 person years. Adjusted RRs (95% CI) for diabetes were 1.27 (1.15–1.41), 1.21 (1.08–1.35), 1.16 (1.04–1.28), and 0.99 (0.86–1.14) for younger women (age 20–64 years), older women (age ≥ 65 years), younger men, and older men, respectively. Conclusion. Younger adults and older women with OA have increased risks of developing diabetes compared to their age-sex matched non-OA counterparts. Further studies are needed to confrm these results and to elucidate the potential mechanisms. 1. Introduction Diabetes mellitus is a common chronic health condition worldwide. It is predicted that the global prevalence of this disease among adults will rise from 6.4% in 2010 to 7.7% by 2030 [1]. Diabetes afects an estimated 8.3% of Americans and 8.8% of Canadians [2, 3], resulting in severe damage to the cardiovascular system, kidneys, eyes, and other organs. Metabolic syndrome is a group of conditions such as hypertension, hyperlipidemia, obesity, and elevated blood glucose that are linked with diabetes [4]. Other common risk factors for diabetes include age, sex, family history, ethnicity, socioeconomic status (SES), heart disease, history of ges- tational diabetes, physical inactivity, alcohol consumption, and diet [5, 6]. As the prevalence of diabetes has risen, it has been imperative to identify determinants beyond these traditional risk factors. Studies have shown that the increased risk of diabetes is caused in part by physical inactivity and that physically active individuals have lower rates of the disease [6, 7]. In addition, muscle strength was found to be signifcantly lower among adults with type 2 diabetes [8]. Osteoarthritis (OA) is the most common type of rheumatic disease and a leading cause of disability [9–11]. More than 10 percent of the world population have OA [12–15]. As OA progresses, severe joint pain limits patients’ physical activity [16, 17]. Recently, OA has been recognized as a metabolic disease [18, 19] linked to metabolic syndrome [20–23]. Moreover, muscle weakness has been observed to be a frequent symptom among OA Hindawi Publishing Corporation International Journal of Rheumatology Volume 2014, Article ID 620920, 7 pages http://dx.doi.org/10.1155/2014/620920