[Type 2 diabetes mellitus: incidence and diagnosis at a primary care center]

To find the annual incidence and reasons for type-2 Diabetes Mellitus (DM2), and the methods used to diagnose it, on the basis of the validation of a computerised record for 1991-1995.

Retrospective, longitudinal study.

Primary care centre.

Of the 387 diabetics registered as new cases in the 1991-1995 period out of 17031 people over 14 who were seen, 21 were not diabetics, 60 were cases of late diagnosis or late recording, 75 came from another centre and 9 were type-1. All these were excluded. The mean age of the 222 (57.4%) real new cases was 59 (ED 11.4). 53% were women. The most common causes of diagnosis were the existence of previous with diagnostic hiperglycemia (50.9%) and the application of protocols for other cardiovascular risk factors (19.8%). The diagnostic methods were two basal glucaemias > or = 140 mg/dl (70.7%), 1 glucaemia > or = 200 mg/dl with typical clinical picture (6.7%) and oral overload of glucose (23%). 97% of cases were diagnosed at the centre itself. The density of annual incidence was 30.1 per 10,000 inhabitants. Prevalence at start and end of the study was 4.4 and 4.9%.

The incidence and prevalence described are greater than described in other studies. The most common reasons for diagnosis were the existence of previous nondiagnostic hyperglycemia and the application of protocols for other risk factors.