RESUMO
BACKGROUND: Alström syndrome is a recessively inherited condition characterised by severe insulin resistance and metabolic syndrome with progression to type 2 diabetes, hepatic dysfunction and coronary artery disease. The metabolic responses to lifestyle changes in the syndrome have not been reported. CASE REPORTS: We describe the effects on glycaemia of intense cycling in two insulin treated Alström patients with diabetes, and the effects of opposite lifestyle changes over one year in two others. METHODS: After practise and clinical assessment two patients aged 21 and 39 years undertook a 380 km cycle ride over 4 days by tandem. The effects of planned reductions in insulin therapies and increased regular carbohydrate ingestion were monitored by frequent capillary blood glucose measurements. Two siblings aged 22 and 25 years underwent assessment of glycaemia, C-peptide/glucose ratio serum lipids, hepatic function and ultrasound, Enhanced Liver Fibrosis test and measures of insulin resistance. Measurements were repeated one year later after profound lifestyle changes. RESULTS: Aerobic exercise strikingly improved blood glucose control despite reduction in insulin dose and increased carbohydrate intake. Increase in exercise and exclusion of fast foods improved all aspects of the metabolic syndrome and induced remission of diabetes in one sibling. Reduction in exercise and consumption of high energy foods in the other resulted in development of type 2 diabetes, severe metabolic syndrome and fatty liver in the other. CONCLUSIONS: Despite dual sensory loss and genetic basis for insulin resistance, Alström patients can successfully ameliorate the metabolic syndrome with lifestyle changes.