The prevalence and characteristics of diffuse idiopathic skeletal hyperostosis in the community-living middle-aged and elderly population: The Yakumo study

Background: The incidence of diffuse idiopathic skeletal hyperostosis (DISH) is increasing with the aging of the population. Asymptomatic DISH can decrease the spinal range of motion (ROM) and cause fractures. However, the prevalence or physical function of patients with DISH before experiencing fractures and other serious conditions is unclear. This study aimed to investigate the prevalence of DISH in the community residents on the basis of age and sex and characterize their physical function, ROM, and bone fragility. Methods: The subjects were community volunteers who attended a health checkup in 2018 and 2019. Overall, 455 subjects (mean age, 64.2 +/- 9.7 years; 177 men) were included for analysis. We performed whole-spine lateral radiography for detecting DISH according to the criteria reported by Resnick. We compared the age, sex, body mass index (BMI), results of muscle strength and walking tests, ROM measured by SpinalMouse (R), and quantitative ultrasound (QUS) of calcaneus with and without DISH. Results: DISH was detected in 83 (18.2%) cases. The DISH group was older (69.8 y.o. vs. 63.0 y.o.; p <0.05) and comprised more men (prevalence: men, 27.7%; women, 12.2%; p < 0.001). BMI was high in the DISH group (24.8 vs. 23.3 kg/m(2), p < 0.05). SpinalMouse measurements showed the DISH group had a significantly decreased ROM in the lumbar spine (43.2 degrees, 57.2 degrees, p < 0.05). The DISH group had a significantly lower T-score on the QUS measurement in the calcaneus (-2.0,-1.5, p < 0.05). There were, however, no significant differences between groups in both muscle strength test and walking test. Conclusion: Subjects with DISH had decreased ROM in the lumbar spine and bone mineral density in calcaneal QUS. However, physical functions such as muscle strength and walking ability were similar among subjects with and without DISH without subjective symptoms.