Background: Musculoskeletal disorders are the key cause of morbidity in elderly people. However, the exact clinical reasons for musculoskeletal disorders related to healthy life expectancy remain elusive. Hence, we aimed to estimate gains in healthy life expectancy from the elimination of musculoskeletal diseases and injuries by using recent national health statistics data in Japan.
Methods: The present data were used from the population, life tables, and the number of deaths in Japan in 2016. Data regarding the activity and disease status of persons living at home were obtained from the 2016 Comprehensive Survey of Living Conditions. We selected eight disorders including musculoskeletal diseases and injuries from the above data: rheumatoid arthritis, arthrosis, low back pain, osteoporosis, fracture, malignant neoplasms, ischemic heart disease, and cerebrovascular diseases. After eliminating each disorder, we calculated the prevalence of limitations in the activities of daily living (ADL) in the population after excluding outpatients with the disorder and ADL limitations, inpatients with the disorder in hospitals and clinics, and people with the disorder who reside in long-term elderly care facilities. The prevalence of non-ADL limitations in the population was calculated after excluding outpatients with the disorder and non-ADL limitations.
Results: Musculoskeletal diseases and injuries generally decreased expected years at birth with activity limitations. In particular, eliminating low back pain and arthrosis decreased expected years at birth with activity limitation to the greatest extent in selected diseases and injuries (male: 0.9 years, female: 1.5 years). However, eliminating malignant neoplasms increased the expected years at birth with activity limitation (male: 1.3 years, female: 1.2 years). In addition, a combination of arthrosis and low back pain led to a moderate decrease in expected years with both ADL (male: 0.7 years, female: 1.1 years) and non-ADL limitations (male: 0.3 years, female: 0.4 years). In contrast, the elimination of malignant neoplasms increased the expected years with both ADL (male: 0.5 years, female: 0.3 years) and non-ADL limitations (male: 0.8 years, female: 0.9 years).
Conclusions: These findings provide clinical evidence that low back pain and arthrosis are the key conditions that can be addressed to prolong healthy life expectancy.