Cardiovascular risk in individuals with and without osteoarthritis using the Canadian Longitudinal Study on Aging

Abstract

Osteoarthritis (OA) is a prevalent and progressive musculoskeletal condition characterized by the degradation of the cartilage and bone and is often comorbid with cardiovascular disease (CVD), with both disease prevalence’s increasing with age. Several factors, such as the site of OA and the menopause transition, are known to independently influence both conditions. OA and CVD share overlapping risk factors and proposed mechanisms, though it is not well understood how these mechanisms influence the risk of comorbidity. This thesis examines the relationship of CVD risk factors, sites of OA, and menopausal variables on CVD risk in individuals with OA. The first aim of this thesis was to examine preclinical markers of CVD risk, namely the carotid intima-media thickness (cIMT) and cardiovascular risk scores, the Framingham risk score (FRS) and the InterHeart risk score (IHRS), in individuals with and without OA to examine differences in CVD risk profiles. Additional considerations were given to the site of OA, as well as non-specific CVD risk factors (such as social disadvantage and frailty). Risk factors were compared between age- and sex-matched individuals with and without OA and between weight-bearing and non-weight bearing OA. Individuals with OA had significantly greater cIMT, FRS, and IHRS, though no differences were found when comparing the site of OA. Unadjusted and multivariate adjusted odds ratios (OR) calculated odds of CVD at 3-year follow-up in the same cohorts. There was a significantly unadjusted (p<0.001, OR:1.70) and adjusted (p<0.001, OR ranging from 1.67-1.70) influence of OA diagnosis on odds of CVD at 3-year follow-up. There was no significant unadjusted or adjusted difference in odds of CVD at 3-year follow-up when comparing different sites of OA (p ranging from 0.24-0.75, OR ranging from 0.69-0.71). The second aim of this thesis was to study CVD risk in post-menopausal women. CVD risk factors and the IHRS were used to calculate differences between age-matched post-menopausal women. Unadjusted and multivariable adjusted ORs calculated odds of CVD at 3-year follow-up. There was a significant unadjusted influence of OA diagnosis (p=0.03, OR:1.34) on CVD outcomes, though the effect of OA diagnosis became non-significant after adjusting for the IHRS (p=0.25, OR:1.36) and the IHRS with menopausal variables (p=0.22, OR:1.40). Although OA is a multifaceted condition, it has often been viewed as a joint-centric disease. The elevated risk of CVD individuals with OA suggests that additional aspects of the OA pathology, such as inflammation and frailty, may drive the increase in risk of CVD independent of age, sex, or menopausal status.