Relationship among Osteoporosis, Sarcopenia, Locomotive Syndrome, and Spinal Kyphosis in Older Individuals Living in a Local Mountain Area.

Study design: Cross-sectional cohort study.

Purpose: This study investigated the relationship among osteoporosis, sarcopenia, locomotive syndrome, and spinal kyphosis in older individuals living in a mountain area.

Overview of literature: Kyphosis greatly reduces the quality of life of older individuals. Osteoporosis and sarcopenia are kyphosiscausing factors.

Methods: This cross-sectional study included 361 individuals aged ≥65 years (mean age, 75.0 years) living in a local mountain area and underwent medical check-ups from 2014 to 2018. The survey items included kyphosis index, body mass index, back pain prevalence, back pain Visual Analog Scale score, Oswestry Disability Index, walking speed, grip strength, skeletal mass index, osteoporosis (% young adult mean [YAM]), LOCOMO 5 score, and presence of sarcopenia (Asian Working Group for Sarcopenia). The participants were divided into the N (kyphosis index: <12; n=229, 63.4%), M (kyphosis index: 12-15; n=99, 27.4%), and K (kyphosis index: ≥15; n=33, 9.2%) groups. p -values of <0.05 were considered statistically significant. An association factor of kyphosis (kyphosis index: ≥15) was investigated with logistic regression analysis.

Results: Age and LOCOMO 5 scores were significantly higher (p <0.05) and %YAM and walking speed were significantly lower (p <0.05) in the K group than in the M and N groups. Other survey items showed significant differences. Only %YAM (odds ratio, 0.20; 95% confidence interval, 0.04-0.96) was an independent factor associated with a kyphosis index of ≥15.

Conclusions: Decreased muscle mass and muscle strength would be related to kyphosis; however, no such relations were noted. Bone loss was significantly related to kyphosis. Osteoporosis-induced decrease in vertebral body height is present in the background. Sarcopenia and locomotive syndrome were not related to kyphosis, whereas decreased bone density was independently associated with kyphosis in older individuals living in a mountain area.