Bone T-scores and functional status: a cross-sectional study on German elderly

Abstract

Background: We explore the association between bone T-scores, used in osteoporosis diagnosis, and functional status since we hypothesized that bone health can impact elderly functional status and indirectly independence.

Methods: In a cross-sectional study (2005-2006) on community dwelling elderly (> = 75 years) from Herne, Germany we measured bone T-scores with Dual-energy X-ray Absorptiometry, and functional status indexed by five geriatric tests: activities of daily living, instrumental activities of daily living, test of dementia, geriatric depression score and the timed-up-and-go test, and two pooled indexes: raw and standardized. Generalized linear regression was used to determine the relationship between T-scores and functional status.

Results: From 3243 addresses, only 632 (19%) completed a clinical visit, of which only 440 (male:female, 243:197) could be included in analysis. T-scores (-0.99, 95% confidence interval [CI], -1.1-0.9) predicted activities of daily living (95.3 CI, 94.5-96.2), instrumental activities of daily living (7.3 CI, 94.5-96.2), and timed-up-and-go test (10.7 CI, 10.0-11.3) (P < = 0.05). Pooled data showed that a unit improvement in T-score improved standardized pooled functional status (15 CI, 14.7-15.3) by 0.41 and the raw (99.4 CI, 97.8-101.0) by 2.27 units. These results were limited due to pooling of different scoring directions, selection bias, and a need to follow-up with evidence testing.

Conclusions: T-scores associated with lower functional status in community-dwelling elderly. Regular screening of osteoporosis as a preventive strategy might help maintain life quality with aging.

Figure 1. Flow-chart of study participants.

Figure 2. Age and numbers across T-scores for whole group (Ai), females (Aii), and males (Aiii).