Heroin Dependence Duration Influences the Metabolic Parameters Mechanisms and Consequences of Impaired Insulin Sensitivity in Hepatitis C Virus Seronegative Heroin Dependents

Objective: Carbohydrate metabolism disorder in heroin dependence is an issue with long history and contradicting results. The aim of the study was to evaluate basal insulin sensitivity in hepatitis C virus seronegative heroin dependents with normal body mass index, taking into consideration the duration of heroin dependence. Method: 78 heroin dependents and 32 healthy controls were enrolled in the cross-sectional, prospective study. The dependents were observed in 2 groups: group 1 with dependence duration less than or equal to 3 years and group 2 with more than 3 years. Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) and β-cell function (HOMA-B%) were used to define basal glucoseinsulin homeostasis. Results: The group with longer dependence duration had HOMAIR(2.23 ± 3.15) significantly higher compared with the control group (1.23 ± 0.53, P = 0.016) but lower compared with the group with the shorter dependence duration (2.65 ± 2.66, P = 0.024), after adjustment for HOMA-B%, waist circumference, and aspartate aminotransferase. The decrease in HOMA-IR during prolonged heroin addiction was significantly associated with the reduced β-cell function (P < 0.001) and waist circumference (P = 0.004). Conclusions: Heroin dependence is associated with increased insulin resistance in hepatitis C virus seronegative heroin dependents.Prolonged heroin use is associated with reduction of basal β-cell pancreatic function with decreased insulin resistance controlled for waist circumference, but still inducing significantly decreased basal insulin sensitivity. Key Words: dependence duration, heroin, HOMA-B%, HOMA-I