[Comparison of indexes for assessing insulin resistance for the health surveillance among workers]. / Confronto tra indici per la valutazione dell'insulinoresistenza nella sorveglianza sanitaria dei lavoratori.

Night shift workers present a high risk to develop metabolic and cardiovascular disorders for alterations that involve effects on circadian rhythms at the level of insulin resistance (IR). Monitor such parameter in this category of workers, therefore, is a crucial step in health surveillance. To this aim, the currently in use test consists in the calculation of the HOMA index [basal insulin (MU/ml) x basal glycemy(mmol/l)/22.5], a measurement with a considerable cost (about 13 Euros). Recent studies demonstrated that the measurement of TyG index calculated as Ln[Triglycerids (mg/dl) x Glucose(mg/dl)/2] and of the triglycerids/HDL-cholesterol ratio correlates with HOMA index. These analyses cost altogether about 5 Euros, allowing a clear decrease of expenses. Our study, carried out on 217 workers at Centre for Obesity and Occupational Medicine of the Occupational Medicine Clinic of Milan, confirmed such correlation and identified the TyG as the index with the best cost/performance ratio. Our future goal is to establish cut-off values, necessary to adopt the TyG as first choice index.