Sex-difference in the association between Triglyceride-Glucose (TyG) index and dementia

Purpose: This study aims to evaluate the association between the insulin resistance as assessed by Triglyceride-Glucose (TyG) index and dementia and to determine whether this relationship varies by sex. Methods: We assessed TyG index in older patients admitted to an Italian Memory Clinic with different cognitive status: 335 (71% females-F) participants with Alzheimer’s disease (AD), 99 (61% F) with vascular dementia (VAD), 301 (67% F) with mixed dementia (MIXED: AD + VAD), 442 (57% F) with mild cognitive impairment (MCI), and 173 cognitively healthy controls (61% F). Results: We found that only in females high TyG index was associated with a greater probability of receiving a diagnosis of MCI (odd ratio - O.R.: 1.91, 95% confidence interval - C.I.: 1.08–3.34), VAD (O.R.: 2.23; 95% C.I.: 1.10–4.51), and MIXED (O.R.: 1.92, 95% C.I.: 1.10–3.33), but not AD (O.R.: 1.07, 95% C.I.: 0.63–1.85). Notably, these associations remained significant in a multi-adjusted model, including age, smoking, total cholesterol and comorbidities. Conclusions: Our findings suggest that insulin resistance may be a risk factor for dementia with a cerebrovascular component, but only in older females.