No increase in new users of blood glucose-lowering drugs in Norway 2006-2011: a nationwide prescription database study.

BACKGROUND: National estimates for the occurrence of diabetes are difficult to obtain, particularly time trends in incidence. The aim was to describe time trends in prevalent and incident use of blood glucose-lowering drugs by age group and gender in Norway during 2005-2011. METHODS: Data were obtained from the nationwide Norwegian Prescription Database. We defined prevalent users of "insulins only" as individuals having no oral antidiabetic drugs (OAD) dispensed from a pharmacy during the previous 24 months or in the subsequent 12 months. Incident users had no blood glucose-lowering drugs dispensed in the previous 24 months; incident "insulins only" users also had no OAD in the subsequent 12 months. RESULTS: In 2011, 3.2% of the population had blood glucose-lowering drugs dispensed, and the incidence rate was 313 per 100,000 person years. The prevalence of OAD use increased from 1.8% in 2005 to 2.4% in 2011; however a decreasing trend in incidence of OAD use was observed, particularly in those aged 70 years and older. In 2010, 0.64% of the population had insulins only dispensed, with an overall incidence rate in the total population of 33 per 100,000 person years which was stable over time. CONCLUSIONS: In this nationwide study, we found that although the prevalent use of OAD had increased in recent years, incident use was stable or had decreased. This may indicate that the increase in diabetes occurrence in Norway is levelling off, at least temporarily.

Can exposure to environmental chemicals increase the risk of diabetes type 1 development?

Type 1 diabetes mellitus (T1DM) is an autoimmune disease, where destruction of beta-cells causes insulin deficiency. The incidence of T1DM has increased in the last decades and cannot entirely be explained by genetic predisposition. Several environmental factors are suggested to promote T1DM, like early childhood enteroviral infections and nutritional factors, but the evidence is inconclusive. Prenatal and early life exposure to environmental pollutants like phthalates, bisphenol A, perfluorinated compounds, PCBs, dioxins, toxicants, and air pollutants can have negative effects on the developing immune system, resulting in asthma-like symptoms and increased susceptibility to childhood infections. In this review the associations between environmental chemical exposure and T1DM development is summarized. Although information on environmental chemicals as possible triggers for T1DM is sparse, we conclude that it is plausible that environmental chemicals can contribute to T1DM development via impaired pancreatic beta-cell and immune-cell functions and immunomodulation. Several environmental factors and chemicals could act together to trigger T1DM development in genetically susceptible individuals, possibly via hormonal or epigenetic alterations. Further observational T1DM cohort studies and animal exposure experiments are encouraged.

[Prevalence of diabetes mellitus in Norway]. / Hvor mange har diabetes mellitus i Norge?

BACKGROUND: Our aim was to combine several regional studies in order to estimate the prevalence of diabetes in Norway. MATERIAL AND METHODS: We used data from a nation-wide registration of type 1 diabetes in the age group < 30 years. Data for other age groups were taken from nine regional surveys, of which six were repeated. The average prevalence of known diabetes based on self-administered questionnaires was estimated. Data on previously undiagnosed diabetes were available from two Norwegian studies and from other countries. RESULTS: The sex and age standardised prevalence of "known" diabetes (all age groups) was estimated at 2.3%, increasing with age to approximately 8% among the 70 to 79-year-olds. The prevalence was 3.4% among those aged > or =30 years. The estimated increase in prevalence of known diabetes over time was 1.4% per calendar year, with variation between sub-groups. The number of unknown cases may be nearly equal to the number of known cases in the age-groups > or =30 years, but this is uncertain. INTERPRETATION: There are probably about 90,000 to 120,000 people with diagnosed diabetes in Norway. Nearly as many may have undiagnosed diabetes, but this is uncertain. Studies representative of the Norwegian population using the oral glucose tolerance test are needed.

Human enterovirus RNA in monthly fecal samples and islet autoimmunity in Norwegian children with high genetic risk for type 1 diabetes: the MIDIA study.

OBJECTIVE: To test whether the frequency of human enterovirus RNA in fecal samples collected monthly from early infancy was associated with development of multiple islet autoantibodies in children with the highest risk HLA genotype. RESEARCH DESIGN AND METHODS: Individuals carrying the HLA DRB1*0401-DQA1*03-DQB1*0302/DRB1*03-DQA1*05-DQB1*02 genotype were identified at birth and followed with monthly stool samples from age 3 to 35 months. Blood samples taken at age 3, 6, 9, and 12 months and then annually were tested for autoantibodies to insulin, GAD 65 and IA-2. Among 911 children, 27 developed positivity for two or more islet autoantibodies in two or more consecutive samples (case subjects). Two control subjects per case subject were matched by follow-up time, date of birth, and county of residence. Stool samples were analyzed for enterovirus with a semiquantitative real-time RT-PCR. RESULTS: The frequency of human enterovirus RNA in stool samples from case subjects before seroconversion (43 of 339, 12.7%) did not differ from the frequency in control subjects (94 of 692, 13.6%) (P = 0.97). Results remained essentially unchanged after adjustment for potential confounders, restriction to various time windows before seroconversion, or infections in the 1st year of life or after inclusion of samples collected after seroconversion. There was no difference in the average quantity of enterovirus RNA or in the frequency of repeatedly positive samples. The estimated relative risk for islet autoimmunity per enterovirus RNA-positive sample during follow-up (nested case-control analysis) was 1.12 (95% CI 0.66-1.91). CONCLUSIONS: There was no support for the hypothesis that fecal shedding of enteroviral RNA is a major predictor of advanced islet autoimmunity.