OBJECTIVE -To examine mortality rates and causes of death among subjects diagnosed with type 1 diabetes aged Յ29 years.RESEARCH DESIGN AND METHODS -Subjects with type 1 diabetes from a population-based register in Yorkshire, U.K., diagnosed between 1978 and 2004 were linked to the U.K. National Health Service Central Register for death notifications. Deaths were coded using ICD-9 (1979ICD-9 ( -2000 and ICD-10 (2001ICD-10 ( -2005. Standardized mortality ratios (SMRs) were calculated using expected numbers of deaths from U.K. mortality rates by cause of death and age at diagnosis.RESULTS -A total of 4,246 individuals were followed up, providing 50,471 person-years of follow-up. Mean follow-up length was 12.8 years for individuals aged 0 -14 years and 8.3 for those aged 15-29 years. Overall, 108 patients died, of whom 77 (71%) were male. A total of 74 (1.7/1,000 person-years) deaths occurred in inidividuals aged 0 -14 years and 34 (4.6/1,000 person-years) in those aged 15-29 years. The SMR was 4.7 (95% CI 3.8 -5.6) overall, similar for males and females, but higher for individuals aged 15-29 years (SMR 6.2 [95% CI 4.3-8.6]) compared with those aged 0 -14 years (4.2 [3.3-5.3]). The SMR rose with increasing disease duration. A total of 47 of 108 deaths (44%) occurred from diabetes complications, 32 of which were acute and 15 chronic. Twenty-two percent (n ϭ 24) of deaths were attributed to accidents or violence (SMR 2.1 [95% CI 1.4 -3.2]), including six suicides. Sixteen percent of all deaths were related to drug misuse (including insulin but excluding tobacco and alcohol) ]).CONCLUSIONS -Subjects with type 1 diabetes diagnosed under 30 years of age had a 4.7-fold excess mortality risk. Nearly half of the deaths were due to acute or chronic complications of diabetes. Drug misuse-related deaths may be an emerging trend in this population warranting further investigation. Diabetes Care 31:922-926, 2008

Objective-To examine whether children offamilies moving from an area of low incidence of childhood diabetes to one which is higher show a corresponding rise in disease incidence.Design-Disease incidence study over 12 years. Setting-Bradford District Metropolitan Council area.Subjects-All subjects aged 0-16' years resident within the study area.Main outcome measures-The incidences ofchildhood diabetes in Asian and non-Asian families.Results-The incidence of diabetes in Asian children increased from 3 1/100QOO per year in 1978-81 to 11-7/100000 per year in 1988-90 (XI for trend=4-95, df=1, p=0026) whereas that for other children remained constant at 10-5/100 000 per year. Over the entire study period rates were lower in Asian females (4-9/100000 per year) than in Asian males (8.8/100 000 per year) whereas the reverse was true for other children (males 9 2/100 000 per year; females 12-0/100 000 per year) (test for common odds ratio: X2=3-81, df=1, p=0052).Conclusions-Offspring of this transmigratory population had a rising incidence of childhood diabetes which was approaching that of the indigenous population. The data provide strong evidence for an environmental effect in the aetiology of insulin dependent diabetes.

A steady and continuing rise in the incidence of Type 1 diabetes over time is observed for children but not for young adults. In parallel, the age at onset is gradually decreasing and more recent birth cohorts are at increased risk. This overall pattern is consistent with the influence of an environmental agent that is gradually affecting children at younger and younger ages.

The incidence of childhood IDDM was associated with environmental factors including population density and overcrowded homes. A possible inference from these data is that patterns of infection are involved in the occurrence of IDDM. Analytical epidemiological studies will be needed to investigate these ideas further.

Children in south Asia have a low incidence of Type 1 diabetes but migrants to the UK have similar overall rates to the indigenous population. However, a more steeply rising incidence is seen in the south Asian population, and our data suggest that incidence in this group may eventually outstrip that of the non-south Asians. Genetic factors are unlikely to explain such a rapid change, implying an influence of environmental factors in disease aetiology. The similarity in rates by age group in the south Asian population is notable.