Prevalence and Incidence of Diabetes in Stockholm County 1990-2010

Background: Diabetes is on the rise in the western world, but data from Scandinavia are inconsistent with indications of stable or even reverse trends. To shed new light on this issue, we investigated diabetes trends in Stockholm County 1990-2010, taking into account trends in risk factors and mortality. Methods: We used data from a large population-based quadrennial public health survey conducted between 1990 and 2010 in Stockholm County (similar to 2.1 million inhabitants), supplemented with data from national registers. The age-standardized prevalence and incidence rates of diabetes and related risk factors 1990-2010 were estimated in adult inhabitants. We also modelled the influence of potential risk factors on the diabetes trends and estimated the life time risk of diabetes. Results: The prevalence of diabetes was 4.6% (95% confidence interval (CI); 4.5-4.8%) in 2010 compared to 2.8% (95% CI; 2.3-3.5%) in 1990. Between 1990 and 2002 the prevalence rose annually by 3.8% (95% CI; 2.1-5.5). Incidence rates showed a similar pattern and rose by 3.0% (95% CI; 0.3-5.7%) annually 1990-2002. The rising incidence was mainly attributable to increasing prevalence of overweight/obesity, which rose by 46% during the observation period. In 2010, the lifetime risk of adult onset diabetes was 28% (95% CI; 26-31%) in men and 19% (95% CI; 17-21%) in women. Conclusions: Diabetes rates have been increasing in Stockholm over the last decades, both in terms of incidence and prevalence, and this development is most likely the result of increasing overweight and obesity in the population.