Objectives The present 4-year follow-up study of the general population was conducted to clarify whether the presence of musculoskeletal diseases, such as, osteoporosis (OP), knee osteoarthritis (KOA), and lumbar spondylosis (LS) could predict the occurrence of sarcopenia (SP) in the near future.
Methods The second survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, a large-scale population-based cohort study, was conducted between 2008 and 2010. We enrolled 1,099 participants (aged ≥60 years; 377 men and 722 women) from the second survey of the ROAD study who had completed assessments of handgrip strength, gait speed, skeletal muscle mass by using bioimpedance analysis, and bone mineral density by using dual X-ray absorptiometry. The third survey was conducted between 2012 and 2013. Of the 1,099 individuals who were enrolled from the second survey, 767 (69.8%; 253 men and 514 women) had completed assessments identical to those in the second survey. SP was defined as per the algorithm of the Asian Working Group for Sarcopenia, while OP at the lumbar spine L2–4 and/or femoral neck was defined according to the World Health Organization criteria. KOA and LS were diagnosed as grade 3 or higher of the Kellgren-Lawrence scale.
Results Among the 767 subjects who completed both the second and third surveys of the ROAD study, the prevalence rates of OP, KOA, and LS in the second survey were 20.5% (men, 3.6%; women, 28.9%), 32.7% (men, 23.1%; women, 37.4%), and 49.8% (men, 46.0%; women, 51.7%), respectively. The cumulative incidence of SP during the 4-year period between the second and third surveys was 2.0%/yr (men, 2.2%/yr; women, 1.9%/yr). After adjustment for confounding factors such as age (yr), gender (0: men, 1: women), regional differences (0: mountainous area, 1: coastal area), and body build (0: normal; body mass index (BMI) ≥18.5 and ≤27.5 kg/m2, 1: emaciation; BMI <18.5 kg/m2, 2: obesity; BMI >27.5 kg/m2), a logistic regression analysis using the occurrence of SP as the objective variable and the presence of OP as the explanatory variable indicated that the presence of OP was significantly associated with the occurrence of SP (odds ratio, 2.51; 95% confidence interval, 1.23–5.11; p =0.011). By contrast, the presence of KOA, and LS was not significantly associated with the occurrence of SP (KOA: 1.32, 0.72–2.41, p =0.369; LS: 1.08, 0.60–1.94, p =0.792).
Conclusions This prospective study suggests that the presence of OP could predict the incidence of SP in the near future, but KOA and LS could not. Treatment of OP might reduce the risk not only of osteoporotic fracture but also of SP.
Disclosure of Interest None declared