Sagittal imbalance and incident long-term care needs in older adults: the locomotive syndrome and health outcomes in the Aizu Cohort Study (LOHAS)

Abstract Background Sagittal imbalance in older adults causes impairments in standing and gait, leading to mobility limitations (defined as “locomotive syndrome” in Japan), which are risk factors for future long-term care needs. This study aimed to investigate whether sagittal imbalance is a risk factor for long-term care needs in older adults. Methods This prospective cohort study included 552 participants from the 2010 Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS). The primary outcome was incident long-term care need, defined as a new certification in the national insurance system during a 5-year follow-up. Sagittal vertical axis (SVA) was measured on a standing whole-spine lateral radiograph. Bodily pain (SF-12) and physical function (3-m timed up and go [TUG] test) were assessed. Association between SVA and incident long-term care needs was evaluated using the Cox proportional hazards model, and hazard ratios (HRs) and 95% confidence intervals [CIs] were calculated, with adjustment for age, sex, pain, TUG, heart disease, and depression. Results During the 5-year follow-up, 63 (11.4%) participants obtained new care needs certification. By SVA categories, incident care needs were observed in 9.1%, 12.7%, and 31.0% of participants in the SVA < 40, 40–95, and > 95 mm groups, respectively. The adjusted HRs [95% CI] for the SVA > 95 mm group were 2.72 [1.26–5.88] versus the SVA < 40 mm group; and 2.13 [0.97–4.70] versus the SVA 40–95 group. Conclusion Severe sagittal imbalance was associated with an increased risk of incident long-term care needs in older adults. Clinical trial number not applicable.