Increasing prevalence of type 2 diabetes in a Scottish population: Effect of increasing incidence or decreasing mortality?

Division of Community Health Sciences, University of Dundee Medical School, Dundee, Scotland, UK.
Diabetologia (Impact Factor: 6.88). 05/2007; 50(4):729-32. DOI: 10.1007/s00125-006-0585-9
Source: PubMed

ABSTRACT We examined incidence, prevalence and mortality from type 2 diabetes mellitus in a Scottish population over 12 years, and evaluated the effects on prevalence of increasing incidence and decreasing mortality.
We used a diabetes clinical information system in Tayside (population 387,908), Scotland, to identify new cases of type 2 diabetes between 1993 and 2004 and to calculate incidence rates and mid-year prevalence. We defined mortality rates as the number of deaths of diabetic people divided by mid-year prevalence. We used logistic and Poisson regression to analyse trends. We then modelled the increase in prevalence for each year for three scenarios, based on whether mortality or incidence rates remained unchanged from 1993.
There was a doubling in incidence and prevalence of type 2 diabetes in Tayside over the 12 years, with statistically significant increasing trends of 6.3 and 6.7% per year respectively. The mortality rate decreased. If incidence and mortality had remained at 1993 levels, there would have been an increase in prevalence of 855 per 100,000 in 2003, accounting for 60.1% of the actual increase of 1,423 per 100,000. If there had been no mortality decrease, prevalence in 2003 would have been very similar to the actual prevalence observed.
Decreasing mortality rates in Tayside had less effect on the increase in prevalence than did increasing incidence. Even if incidence and mortality remain unchanged, prevalence will increase by over 20% in the next decade.

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Available from: Josie Evans, Jan 29, 2014
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    • "and in Canada [10] [11]. The Scottish system covers the entire population as of 2000 and is virtually complete, collecting information from several administrative databases to form the register; however the system is recently established , so no official publications for the total of Scotland exist, only from the pioneering region Tayside [8]. The Canadian system is based in the National Diabetes Surveillance System (NDSS) that collects data from all states of Canada and issues reports annually [11]. "
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    Scandinavian Journal of Public Health 07/2011; 39(7 Suppl):175-9. DOI:10.1177/1403494811404279 · 3.13 Impact Factor
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    • "In the Tayside region (population ≈ 400,000), Scotland is a registry operating [13] based on record linkage from more sources than the Danish register. They found [14] similar prevalence of diabetes in 1996 (1.94% compared to 1.89% in Denmark) and similar increase in prevalence (6.7%/year, compared to 6.3%/year(M) and 6.6%/year(F) in Denmark). In the Skaraborg region BxC, JKK, PO & KBJo: (population ≈ 300,000) Sweden, a registry based on clinical recordings of patients [15] found a prevalence of 3.2% in 1995, somewhat higher than found in Denmark. "
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    Diabetologia 10/2008; 51(12):2187-96. DOI:10.1007/s00125-008-1156-z · 6.88 Impact Factor
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    • "We observed a considerable increase in the prevalence of diabetes of about 1% annually. These fi ndings are in accordance with results of other epidemiologic studies in North America and the Mediterranean region, which suggests that, apart from the increase in the prevalence of diabetes, an increased incidence of diabetes also occurred during the last 30 years worldwide (Geiss et al 2006; Fox et al 2006; Evans et al 2007). For example, the prevalence of diabetes in Greece is close to the prevalence in USA (ie, 9.6%) (Geiss et al 2006), in Spain (ie, 11%) (Velverde Table 1 Five-year incidence of type 2 diabetes mellitus in men and women by age group. "
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