Association of kyphotic posture with loss of independence and mortality in a community-based prospective cohort study: the Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS)

• Published in: BMJ open 2022-03, Vol.12 (3), p.e052421-e052421
• Main Authors: Hijikata, Yasukazu, Kamitani, Tsukasa, Sekiguchi, Miho, Otani, Koji, Konno, Shin-ichi, Takegami, Misa, Fukuhara, Shunichi, Yamamoto, Yosuke
• Format: Article
• Language: English
• Subjects: Age; Aged; Back pain; Body mass index; Cohort analysis; Cohort Studies; Disease; Fractures; Geriatric Medicine; Health insurance; Humans; Kyphosis; Mortality; musculoskeletal disorders; Older people; Outcome Assessment, Health Care; Population; Posture; Prospective Studies; Public health; spine
• ISSN: 2044-6055; 2044-6055
• DOI: 10.1136/bmjopen-2021-052421

ObjectivesThis study aimed to investigate the association between kyphotic posture and future loss of independence (LOI) and mortality in community-dwelling older adults.DesignProspective cohort study.SettingTwo Japanese municipalities.ParticipantsWe enrolled 2193 independent community-dwelling older adults aged≥65 years at the time of their baseline health check-up in 2008. Kyphotic posture was evaluated using the wall-occiput test (WOT) and classified into three categories: non-kyphotic, mild (>0 and ≤4 cm) and severe (>4 cm).Primary and secondary outcome measuresThe primary outcome was mortality and the secondary outcomes were LOI (new long-term care insurance certification levels 1–5) and a composite of LOI and mortality. A Cox proportional hazards model was used to estimate the adjusted HRs (aHRs).ResultsOf the 2193 subjects enrolled, 1621 were included in the primary analysis. Among these, 272 (17%) and 202 (12%) were diagnosed with mild and severe kyphotic postures, respectively. The median follow-up time was 5.8 years. Compared with the non-kyphotic group, the aHRs for mortality were 1.17 (95% CI 0.70 to 1.96) and 1.99 (95% CI 1.20 to 3.30) in the mild and severe kyphotic posture groups, respectively. In the secondary analysis, a consistent association was observed for LOI (mild: aHR 1.70, 95% CI 1.13 to 2.55; severe: aHR 2.08, 95% CI 1.39 to 3.10) and the LOI-mortality composite (mild: aHR 1.27, 95% CI 0.90 to 1.79; severe: aHR 1.83, 95% CI 1.31 to 2.56).ConclusionKyphotic posture was associated with LOI and mortality in community-dwelling older adults. Identifying the population with kyphotic posture using the WOT might help improve community health.