EXPRESS: Associations of the triglyceride/HDL-cholesterol ratio and triglyceride–glucose index with malnutrition risk and other geriatric parameters in older adults: a retrospective cross-sectional study

Background/Objectives: This study aimed to investigate the association of the triglyceride/HDL-cholesterol ratio (THR) and the triglyceride–glucose (TyG) index with malnutrition risk and other geriatric parameters among patients attending a geriatric outpatient clinic. Methods: A total of 355 patients aged ≥65 years who presented to the geriatric outpatient clinic and completed a comprehensive geriatric assessment (CGA) were retrospectively evaluated in this study. Patients were divided into tertiles according to THR and TyG values. Mini Nutritional Assessment–Short Form (MNA-SF) and CGA parameters were recorded and compared between groups. Malnutrition risk was defined as MNA-SF <12. Results: The median age of patients was 79 years (59.7% female). Regarding comorbidities, TyG and THR values were higher in the presence of diabetes mellitus, coronary artery disease, and malignancy (all p<0.05). In unadjusted analyses, gait speed was positively correlated with both TyG and THR (both p<0.05). Higher THR and TyG values were correlated with higher MNA-SF scores, and MNA-SF score remained associated with both indices in multivariable linear regression analyses. In binary logistic regression adjusted for age, sex, body mass index, and diabetes, both indices were associated with malnutrition risk (MNA-SF <12; present in 69.6% of patients) and with impaired Timed Up and Go test performance; the association with malnutrition risk persisted after additional adjustment for basic activities of daily living, instrumental activities of daily living, depression, and comorbidity burden, in which higher THR was also associated with higher odds of Clinical Frailty Scale >4. After multiple-testing correction, only the association of THR with malnutrition risk remained significant. THR and TyG had limited discriminative power for malnutrition risk (area under the curve 0.601 [95% CI 0.535–0.667] and 0.592 [95% CI 0.526–0.659], respectively). Conclusion: Within the observed range, higher THR and TyG values were associated with lower malnutrition risk in older outpatients. Because their discriminative power is limited, these indices should not be considered independent screening or diagnostic tools; reverse causality cannot be excluded, and prospective studies are needed.