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TOFI phenotype - its effect on the occurrence of diabetes
Zygmunt Zdrojewicz1, Ewa Popowicz2, Marta Szyca2
1Department and Clinic of Endocrinology, Diabetology and Isotope Therapy, Wroclaw Medical University.
Abstract:
Recent studies have reported a significant increase in the incidence of type 2 diabetes in the past 30 years. They also predict that this trend will continue. This is related to a change in lifestyle, which results in a parallel increase in the incidence of overweight and obesity. However, symptoms of the metabolic syndrome, so far closely related to abdominal obesity, are relatively common among people with normal body mass index (BMI) and waist circumference. The aim of the study is to present the TOFI phenotype (thin outside, fat inside) as an important factor in pathogenesis of type 2 diabetes. In the 1980s, the first study of the MONW (metabolic obese normal weight), a phenotype that is characterized by metabolic diseases in people with normal body weight. Since then, no uniform criteria have been established for MONW deployment, which has created difficulties in identifying affected individuals. Recent work has appeared describing the TOFI phenotype, which seems to lead to the appearance of MONW. People affected by this problem, in spite of undersized fatty tissue, have an increased amount of adipose tissue surrounding the internal organs, which increases the risk of insulin resistance and type 2 diabetes. In the diagnostics of the TOFI phenotype, magnetic resonance imaging is of paramount importance. Previous studies did not provide clear answers about the pathogenesis of TOFI nor which factors stimulate its development. Prophylaxis and treatment of the syndrome include increased physical activity, the promotion of correct eating habits, and a use of metformin.
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