Incidence of diabetes amongst people aged 18-50 years in nine British towns: a collaborative study.

The incidence of diabetes among people aged 18-50 years has been studied prospectively in nine towns, chosen to encompass the range of socio-economic conditions and spread of latitude in England and Wales. The incidence of Type 1 (insulin-dependent) diabetes in this age group varied little between the towns. However, the incidence of Type 2 (non-insulin-dependent) diabetes was markedly higher in the towns with 'worse' socio-economic conditions. The mean incidences were 23 per 100 000 for the three 'worse' towns and 10 per 100 000 for the three 'better' towns. This was not explicable by an association between the disease and social class. This finding has to be reconciled with known and hypothesised influences in the aetiology of Type 2 diabetes.