Functional category, physical frailty, and sarcopenia in older adults with diabetes mellitus: a cross-sectional study

To describe how a three-level functional category (DAFS-8; lower categories indicating better function) overlaps with physical frailty and sarcopenia in older outpatients with diabetes, and to explore whether their combination provides clinically interpretable risk stratification for prioritizing care.

We conducted a cross-sectional study of 122 outpatients aged ≥ 65 years. Physical frailty was defined by the revised Japanese Cardiovascular Health Study (J-CHS) phenotype, and sarcopenia/possible sarcopenia by the AWGS 2019 criteria. Discriminative performance was evaluated using receiver operating characteristic (ROC) analyses and rule-based performance metrics.

Prefrailty/frailty, sarcopenia, and possible sarcopenia were present in 70.5%, 23.8%, and 64.8% of participants, respectively. Sarcopenia was almost exclusively concentrated among those classified as prefrail or frail (96.6%). The intersection of prefrailty/frailty and functional category II/III captured 48.3% of sarcopenia cases. While frailty alone showed high sensitivity (96.6%) but limited specificity (37.6%), this intersection-based condition showed higher specificity (80.6%) and positive predictive value (43.8%). ROC analyses showed a numerically higher AUC when functional category was added to frailty (0.733 vs. 0.671), although the confidence intervals overlapped.

Functional category and physical frailty capture complementary aspects of vulnerability. Sarcopenia in older adults with diabetes was not uniformly distributed across frailty states but was specifically concentrated within the prefrail-to-frail spectrum. Their overlap identifies subgroups where sarcopenia is disproportionately enriched, supporting a potential triage perspective for prioritizing interventions in routine outpatient care. These findings illustrate how multiple geriatric "measuring sticks" capture distinct but overlapping segments of this heterogeneous population.