Association between visual classification of kyphosis and future ADL decline in community-dwelling elderly people: the Kurabuchi study

SUMMARY: This cohort study conducted in Japan showed that severe age-related kyphosis was visually detected. The visual assessment of kyphosis was associated with declines in ADL, suggesting that we can easily identify people at high risk to develop future ADL reduction in the community setting. PURPOSE: Age-related kyphosis is related with declines in activities of daily living (ADL). Its conventional diagnosis has been made by orthopedic surgeons and trained examiners using specialized equipment such as X-rays. We investigated whether visual classification of kyphosis by laypersons accurately predicted future ADL decline. METHODS: This study was part of the Kurabuchi Study, a cohort study of community-dwelling elderly Japanese. Between 2009 and 2010, three layperson raters used reference illustrations to classify 532 participants without ADL decline at study baseline into four categories. Other examiners used conventional methods to assess kyphosis in the same participants: curve ruler, Spinal Mouse, and the block method. ADL decline was defined as the development of dependence according to the Katz Index, admission to a nursing home, or certification of long-term care need. RESULTS: Thirty-five of the participants (6.6%) were classified with the most severe degree of kyphosis at baseline by visual assessment. Interrater agreement was high (Kappa = 0.73) for the most severe group. During 4.5 years of follow-up, 106 participants (19.9%) showed ADL decline. On the basis of visual assessment, the adjusted risk ratio for ADL decline among the participants with the most severe kyphosis was 2.6 (95% CI: 1.4–4.6). Assessments of kyphosis made with the Spinal Mouse also accurately predicted ADL decline. CONCLUSIONS: Visual assessment of kyphosis predicted future declines in ADL in this study. Since our method requires no special tools or training, it may be useful for identifying those at high risk of ADL decline. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11657-018-0551-4) contains supplementary material, which is available to authorized users.