Author(s): MUÑOZ-PÉREZ, I., SANTISTEBAN, A., LARRINAGA-UNDABARRENA, A., RÍO, X., Institution: UNIVERSITY OF DEUSTO, Country: SPAIN, Abstract-ID: 625

INTRODUCTION:
Ageing is associated with a progressive decline in muscle mass, strength and power, leading to a deterioration in muscle quality and an increased risk of frailty, dependency and mortality. There are numerous proposals for classifying frailty; however, it remains necessary to determine whether the indices used adequately reflect the patient's overall functional status.Therefore, the objective of this study is to analyse whether there is a significant concordance between the MQI calculated using hand dynamometry and the SPPB battery, which is directly linked to lower limb functionality.
METHODS:
A total of 1.221 older adults (89.6% women) with a mean age of 78.10 +/- 5.81 voluntarily participated in this descriptive cross-sectional study, which examines the results of functional capacity tests data in older adults. To assess physical function, the SPPB test (Guralnik et al., 1994) was performed and the MQI was measured using handgrip strength divided by relative skeletal muscle mass (Barbat-Artigas et al., 2012).

RESULTS:
Agreement between MQI and SPPB classifications was limited. The contingency table showed that MQI classified 807 participants as frail, including all individuals identified as frail by SPPB (n = 52), but also the majority of those classified as pre‑frail (n = 437) and a substantial proportion of those classified as normal (n = 318). MQI rarely used the pre‑frail category (n = 203), and only participants classified as normal by SPPB were assigned to this category. Overall accuracy was 21.5% (95% CI: 19.3-23.9), significantly lower than the no‑information rate (59.9%). The unweighted Cohen’s Kappa was 0.03, indicating virtually no agreement, while the weighted Kappa was 0.225, reflecting weak concordance between instruments. McNemar’s test showed highly asymmetric misclassification patterns (p < 0.001).
CONCLUSION:
Low concordance was observed between MQI and SPPB, indicating that they assess different aspects of frailty. MQI showed a stricter classification, potentially overestimating frailty when based solely on muscle quality. These findings support the need for multidimensional functional assessment in older adults.

Barbat-Artigas S, Rolland Y, Vellas B, Aubertin-Leheudre M. How to assess functional status: a new muscle quality index. J Nutr Health Aging. 2012; 16(1):67–77. doi:10.1007/s12603-012-0004-5.

Guralnik JM, Simonsick EM, Ferrucci L, Glynn RJ, Berkman LF, Blazer DG, Scherr PA, Wallace RB. A short physical performance battery assessing lower extremity function: association with self-reported disability and prediction of mortality and nursing home admission. J Gerontol. 1994; 49(2):M85-94. doi: 10.1093/geronj/49.2.m85. PMID: 8126356.