CLINICAL STUDY Evaluation of insulin resistance in a cohort of HIV-infected youth Raffaella Rosso, Arianna Parodi 1 , Giuseppe d’Annunzio 1 , Francesca Ginocchio, Laura Nicolini, Chiara Torrisi 1 , Maria Pia Sormani 2 , Renata Lorini 1 , Claudio Viscoli and Marina Vignolo 1 Department of Infectious Diseases, San Martino Hospital, University of Genoa, Largo R. Benzi 10, 16132 Genoa, Italy, 1 Paediatric Clinic, G. Gaslini Institute, University of Genoa, Largo G. Gaslini 5, 16147 Genoa, Italy and 2 Biostatistics Unit, Department of Health Sciences, San Martino Hospital, University of Genoa, Via Pastore, 16132 Genoa, Italy (Correspondence should be addressed to R Rosso; Email: raffaella.rosso@unige.it) Abstract Objective: Metabolic abnormalities, including impairment of glucose homeostasis, have been well characterized in HIV-infected patients. In contrast to adults, insulin resistance and diabetes mellitus appear to be relatively uncommon finding in youth. Design: We assessed insulin resistance, and associated risk factors, in a population of vertically HIV-infected children and young adults, when compared with a control population of healthychildren. Methods: At the time of enrolment, weeks of pregnancy, birth weight, sex, age, weight, height, body mass index (BMI), pubertal stages, CDC classification, blood pressure, clinical lipodystrophy, hepatitis B or C co-infection, antiretroviral therapy, CD4 T lymphocyte counts, and HIV-RNA levels were recorded. Fasting plasma glucose and insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) were determined. These parameters were compared between HIV patients and healthy controls with multivariate analyses. Results: Fasting insulin levels (ORZ1.21, P!0.001) and glycemia (ORZ0.89, P!0.001) were significantly different between HIV-infected patients and controls. Antiretroviral therapy duration (rZ0.281, P!0.05), triglyceride levels (rZ0.286, P!0.05), age (rZ0.299, P!0.05), and BMI SDS (rZ0.485, P!0.001) were significant predictor variables of insulin resistance, expressed as HOMA- IR. Moreover, clinical lipodystrophy seems to be stronglycorrelated to glycemia (P!0.05), triglyceride levels (P!0.05), serum insulin levels (P!0.001), HOMA-IR (P!0.05), and also with therapy duration (P!0.05). Conclusions: Both HIV infection and antiretroviral therapy demonstrate differential effects on glucose metabolism in HIV-infected children. Targeted prevention of insulin resistance and diabetes mellitus in HIV-infected children and young adults is needed in order to avoid the associated long-term complications that would otherwise occur, given the improvement in life expectancy of HIV-infected individuals. European Journal of Endocrinology 157 655–659 Introduction Disorders of glucose metabolism ranging from reduction in insulin sensitivity to impaired glucose tolerance (IGT) and diabetes mellitus has recently been recognized in HIV-infected patients (1–4). The condition appears to be multifactorial in cause, involving adverse effects of antiretroviral medications and HIV-related viral and immunologic factors, as well as genetic influences, physical inactivity, and diet (5, 6). Metabolic abnormalities, including IGT, dyslipidemia, and alterations in body fat distribution, have not been characterized in children to the same extent as in adults (1). In contrast to adults, insulin resistance (IR) and diabetes mellitus appear to be relatively uncommon in children (2–4). The standard technique for assessment of insulin sensitivity is the hyperinsulinemic–euglycemic clamp, which is often combined with the hyperglycemic clamp to determine the adequacy of compensatory b-cell hypersensitivity (7, 8). Several fasting or ‘homeostatic’ models have been proposed as non-invasive measure- ment techniques for insulin sensitivity, with a relatively good correlation with clamp techniques (9–11). The homeostatic model assessment-IR (HOMA-IR), fasting glucose/insulin ratio (FGIR), and quantitative insulin sensitivity check index (QUICKI) methods have been most frequently used in clinical investigations (12). As a measure of IR among childhood, HOMA-IR has been used more often than QUICKI and FGIR, although the pediatric cutoff is unclear (12–15). The aim of the present study was to assess IR, and risk factors associated, in a population of vertically HIV-infected European Journal of Endocrinology (2007) 157 655–659 ISSN 0804-4643 q 2007 Society of the European Journal of Endocrinology DOI: 10.1530/EJE-07-0414 Online version via www.eje-online.org Downloaded from Bioscientifica.com at 04/25/2020 03:13:17PM via free access