LB106 - ASSOCIATION BETWEEN SERUM OSMOLALITY AND SKELETAL MUSCLE MASS IN INDEPENDENT COMMUNITY-DWELLING OLDER WOMEN WITH EXERCISE HABITS: A PRELIMINARY STUDY

LB106

ASSOCIATION BETWEEN SERUM OSMOLALITY AND SKELETAL MUSCLE MASS IN INDEPENDENT COMMUNITY-DWELLING OLDER WOMEN WITH EXERCISE HABITS: A PRELIMINARY STUDY

Y. Hasegawa^1,*, K. Ogai¹, K. Kato^2,3, C. Konya², H. Sanada², T. Minematsu²

¹Department of Bio-engineering Nursing,, ²Department of Adult & Gerontological Nursing, Ishikawa Prefectural Nursing University, Kahoku, ³Division of Nursing, Kanazawa University Hospital, Kanazawa, Japan

Rationale: Dehydration has been suggested as a potentially modifiable factor for preventing muscle mass decline in older adults. However, the relationship between hydration status and skeletal muscle mass in independent community-dwelling older adults with regular exercise habits remains unclear. In this study, we examined the association of serum osmolality and skeletal muscle mass in independent community-dwelling older adults who regularly exercised.

Methods: This secondary analysis used data from a cross-sectional observational study conducted in September 2024 among ≥ 65-year-old community-dwelling adults participating in weekly exercise in a regional city in Japan, selecting women from the original study population with preserved renal function (i.e., estimated glomerular filtration rate: ≥ 60 mL/min/1.73 m²). Hydration status was assessed using serum osmolality. The predicted skeletal muscle mass index (pSMI) was calculated using serum creatinine, cystatin C, hemoglobin, age, and body weight data from the original study. Associations were assessed using Spearman’s rank correlation coefficients. This study was approved by the Ethics Committee of Ishikawa Prefectural Nursing University (2024-28-2).

Results: A total of 22 participants were included in the analysis (median age: 76.0 years; interquartile range: 73.0–78.5). pSMI negatively correlated with serum osmolality (ρ = −0.430; p = 0.046), and it positively correlated with body weight (ρ = 0.941; p < 0.001) and body mass index (ρ = 0.769; p < 0.001). No significant correlations were observed between the pSMI and age or serum albumin.

Conclusion: Higher serum osmolality was associated with lower pSMI, indicating dehydration as a potential contributing factor to reduced skeletal muscle mass. Further prospective studies are warranted. 

Disclosure of Interest: Y. Hasegawa Other: Affiliated with a department funded by Saraya Co., Ltd. (Osaka, Japan). , K. Ogai Other: Affiliated with a department funded by Saraya Co., Ltd. (Osaka, Japan). , K. Kato: None declared, C. Konya: None declared, H. Sanada: None declared, T. Minematsu: None declared