The impact of musculoskeletal diseases on mortality-comparison with internal diseases: A 15-year longitudinal study

Background: Aging is associated with an increased incidence of diabetes (DM), hypertension (HT), hyperlipidemia (HL), as well as musculoskeletal disorders, such as osteoarthritis (OA) and osteoporosis (OP). However, the impact of musculoskeletal disorders on mortality remains unclear. This study investigated the risk of mortality if having knee OA or OP. Methods: 601 participants (mean age 67.8 +/- 5.3 years) who underwent musculoskeletal check-ups in Yakumo town were enrolled in this study, 248 were males and 353 were females. The following parameters were assessed: age, sex, body mass index, smoking habit, alcohol drinking habit, physical exercise habit, knee OA, OP, HT, DM and HL. Kaplan-Meier survival curves for smoking, drinking and physical exercise habits, knee OA, OP, HT, DM and HL were prepared, and the log-rank test was performed. Furthermore, the Cox hazard model was used for multivariate analysis of all variables. Results: Knee OA, OP, HT, and DM were associated with a significantly higher mortality rate. Cox regression analysis results showed a hazard ratio of 1.972 for OA (95% CI: 1.356-2.867), 1.965 for DM (1.146-3.368), 1.706 for smoking habits (1.141-2.552), and 1.614 for OP (1.126-2.313). Cardiovascular diseases were the most common causes of death. Conclusions: Smoking, knee OA, OP and DM were all associated with increased risk of mortality. Knee OA had a high hazard ratio, comparable to that of DM. These findings suggest that interventions against smoking, knee OA, OP and DM may reduce the risk of mortality. (C) 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.