Type 2 diabetes has been predicted to be one of the major health challenges of the 21st century. Currently, diabetes accounts for 3.8m deaths a year, a similar magnitude to deaths related to HIV and AIDS. In the UK it is estimated than half a million people are unaware they have diabetes, and last year 100,000 new cases were diagnosed.

A recent Canadian paper, examining the epidemiology of diabetes, suggests that the epidemic is already upon us.

Lipscombe and Hux reviewed the incidence and prevalence of diabetes in Ontario, which has a population of more than 7.9m, between 1995 and 2005 using entries in a validated diabetes registry. The database included patients with at least one hospital admission or two physician claims with diabetes as a diagnosis. Gestational diabetes was excluded. The database was shown to have a high sensitivity and specificity (86 per cent and 97 per cent respectively).

The results showed an age- and sex-adjusted increase in prevalence of almost 69 per cent. The study found a 94 per cent rise in type 2 diabetes in the 20-49 age group, possibly confirming fears that obesity may be increasing the incidence of diabetes at younger ages. The only glimmer of hope was that the mortality rate in patients with diabetes had fallen. However, this may not correlate accurately; in the UK, for example, death certification does not always mention diabetes as the underlying cause of vascular death.

The authors acknowledge that Ontario has a large immigrant population from countries with high prevalence of diabetes, but their findings are supported by recent publications from the International Diabetes Federation (IDF) and an NSF update from the DH.^1,2

New data published in the IDF atlas suggest that diabetes, mostly type 2, now affects 5.9 per cent of the world's adult population, equating to 246 million people. Almost half of these patients are less than 60 years of age. The NSF update states that the prevalence of diabetes in the UK is predicted to increase by 15 per cent between 2001 and 2010.

These huge figures are hard to set against individual experience, but when I started a practice diabetes clinic in 1991 we had just over 100 patients. We now have nearly 400 and new cases are appearing with frightening rapidity. The epidemic is here.

Lipscombe L, Hux J. Trends in diabetes prevalence, incidence, and mortality in Ontario, Canada 1995-2005: a population-based study Lancet 2007;369:750-56