Insulin resistance risk in domestic workers: a sex-specific assessment using TyG, METS-IR, and SPISE indices in a large Mediterranean cohort.

Abstract

Introduction: Introduction: insulin resistance is a key contributor to cardiometabolic diseases, yet it remains understudied among domestic workers. This study evaluates the usefulness of the TyG, METS-IR, and SPISE indices as non-invasive tools to estimate insulin resistance risk in this population. Objective: insulin resistance (IR) is a major precursor of type 2 diabetes and cardiovascular disease, yet its prevalence and associated factors remain underexplored in informal labor sectors. This study aimed to evaluate the prevalence of elevated IR scores using validated non-invasive indices (TyG, METS-IR, and SPISE) and their association with sociodemographic and lifestyle variables in a large cohort of Spanish female domestic workers. Methods: a cross-sectional analysis was conducted using health examination data from 6,321 adult female domestic workers in Spain. IR was assessed using three surrogate indices: the triglyceride-glucose index (TyG), the metabolic score for insulin resistance (METS-IR), and the single-point insulin sensitivity estimator (SPISE). Participants were classified into quartiles based on each index. Associations with age, smoking status, physical activity (IPAQ-SF), and adherence to the Mediterranean diet were evaluated using logistic regression models adjusted for potential confounders. Results: a high proportion of participants were in the highest-risk quartile for TyG (25.3 %), METS-IR (24.9 %), and the lowest-risk quartile for SPISE (26.8 %). Older age, smoking, low physical activity, and low Mediterranean diet adherence were significantly associated with unfavorable IR profiles across all three indices. Multivariate logistic regression showed that physical inactivity was strongly associated with high TyG (OR = 3.12), high METS-IR (OR = 3.28), and low SPISE (OR = 4.07) scores. The prevalence of high IR scores increased with age and was notably higher among smokers and individuals with poor dietary habits. Conclusions: this study reveals a concerning prevalence of elevated insulin resistance among female domestic workers in Spain and identifies modifiable lifestyle factors associated with metabolic risk. The use of simple, cost-effective indices such as TyG, METS-IR, and SPISE offers a valuable opportunity for early identification of cardiometabolic risk in underserved labour populations. Targeted interventions promoting physical activity, dietary improvement, and smoking cessation are urgently needed to reduce long-term health disparities in this occupational group.