Prevalence of known and previously unknown diabetes mellitus and impaired glucose tolerance in an adult norwegian population. Indications of an increasing diabetes prevalence. The nord-trøndelag diabetes study

Abstract

Objective - To establish the prevalence of known and undiagnosed diabetes mellitus and impaired glucose tolerance in a representative Norwegian adult population according to the 1980 World Health Organization Expert Committee diagnostic criteria. Design - Screening survey applying questionnaire and non-fasting blood glucose followed by a fasting and an oral glucose tolerance test. Setting - the county of Nord-Trøndelag, Norway, 1984-86. Subjects - All inhabitants aged >20 years (85 100); 90.3% participated. for previously unknown diabetes: all inhabitants >40 years (53 001) - participation rate 84.7% Main outcome measure - Prevalence. Results - the prevalence of previously known diabetes was 2.6% in men and 3.2% in women. Total diabetes prevalence >40 years was 4.8% in men and 5.6% in women. the prevalence increased continuously with age until 90 years. One patient in five was previously undiagnosed. Impaired glucose tolerance in those with an abnormal non-fasting value was rare; only 0.9% in men and 0.2% in women. the prevalence of known diabetes was three times higher than 20-30 years ago and four times higher than 50 years ago. Except for known diabetes in the very old the prevalence corresponded well with recent Nordic studies. Implications - the present diabetes prevalence was so high that interested general practitioners will get sufficient experience in follow-up of diabetic patients to facilitate a good quality of the care. © 1995 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.