How many people inject insulin? UK estimates from 1991 to 2010.

AIMS: We set out to estimate the prevalence rate of insulin use in the UK population, the total number of people in the UK who use insulin, the proportion of users with type 1 and type 2 diabetes and changes between 1991 and 2010. METHODS: Patients receiving prescriptions for insulin were identified in the Clinical Practice Research Datalink and attributed a diagnosis of type 1 or type 2 diabetes. The annual prevalence of insulin use was calculated and applied to population data. RESULTS: The crude prevalence rate of insulin use increased from 2.43 (95% CI 2.38-2.49) per 1000 population in 1991 to 6.71 (6.64-6.77) per 1000 in 2010. The largest change was an increase in the prevalence of insulin users with a diagnosis of type 2 diabetes from 0.67 (0.64-0.70) to 4.34 (4.29-4.39) per 1000 population. The absolute number using insulin increased from 137 000 people (121 000-155 000) in 1991 to 421 000 (400 000-444 000) in 2010. The proportion taking insulin alone (as against combination with oral agents) decreased from 97% in the first decade to 37% in the second. CONCLUSION: The number of people using insulin trebled between 1991 and 2010, largely due to a considerable increase in the number of people with type 2 diabetes using insulin.

Estimation of primary care treatment costs and treatment efficacy for people with Type 1 and Type 2 diabetes in the United Kingdom from 1997 to 2007*.

AIMS: The purpose of this study was to characterize the financial cost and efficacy of primary care treatment for diabetes in the United Kingdom from 1997 to 2007. METHODS: Retrospective data were analysed for people with Type 1 and Type 2 diabetes along with matched control subjects using data from The Health Improvement Network. Costs were attributed from published sources and adjusted for price inflation. Type 2 diabetes was analysed by five commonly used treatment regimens. RESULTS: It was possible to identify 126 052 people for inclusion: 11 300 (8.9%) with Type 1 diabetes and 114 752 (91.1%) with Type 2. The overall mean prescribing costs per person per year (pppy) increased markedly for people with diabetes from 1997 to 2007: for Type 1, from 573 pounds to 1014 pounds pppy (+77%), and for Type 2, from 39 pounds to 740 pounds pppy (+89%). In 2007, diabetes-treatment-specific prescribing represented 57% of prescribing costs in Type 1 diabetes and 28% in Type 2 diabetes. In Type 2 diabetes there was a mean of 5.4 primary care consultations in 1997, increasing to 11.5 pppy in 2007 (+112%). In 1997 the total mean cost of primary care treatment for Type 2 diabetes was 602 pounds pppy, increasing to 1080 pounds in 2007. In Type 1 diabetes, the mean glycated haemoglobin decreased by 0.1% from 8.8% in 2001 to 8.7% in 2007; the corresponding change using insulin in Type 2 diabetes was also 0.1%. Greater improvement in blood pressure and lipids was evident. CONCLUSIONS: Over the 10 year period to 2007, diabetes-related primary care adjusted costs increased considerably, whereas glycated haemoglobin values did not improve at all over the same period.

Autoantibodies to IA-2beta improve diabetes risk assessment in high-risk relatives.

AIMS/HYPOTHESIS: The aim of this study was to evaluate the prognostic significance of autoantibodies to IA-2beta (IA2betaA) in a large, well-characterised population of islet cell antibody (ICA)-positive relatives followed for 5 years in the European Nicotinamide Diabetes Intervention Trial. METHODS: Autoantibodies to insulin (IAA), glutamate decarboxylase (GADA) and IA-2 (IA2A) were measured in 549 participants at study entry, and IA2A-positive samples tested for IA2betaA. First-phase insulin response (FPIR) and oral glucose tolerance were determined at baseline. RESULTS: Of 212 ICA/IA2A-positive participants (median age 12.1 years; 57% male), 113 developed diabetes (5 year cumulative risk 56%), and 148 were also GADA-positive and IAA-positive (4Ab-positive). IA2betaA were detected in 137 (65%) ICA/IA2A-positive participants and were associated with an increased 5 year diabetes risk (IA2betaA-positive 65 vs 39% in IA2betaA-negative, p=0.0002). The effect was most marked in 4Ab-positive relatives (72% vs 52%, p=0.003). Metabolic testing further refined risk assessment. Among 101 4Ab-positive relatives with IA2betaA, the 5 year risk was 94% in those with a low FPIR (vs 50% in those with a normal FPIR, p<0.0001), and 95% in those with impaired glucose tolerance (IGT) (vs 66% in those with normal glucose tolerance, p<0.0001). The median time to diagnosis of 4Ab/IA2betaA-positive participants with a low FPIR was 1.5 years. Multivariate analysis confirmed IA2betaA status, antibody number, young age, FPIR and IGT as independent determinants of risk. CONCLUSIONS/INTERPRETATION: IA2betaA are associated with a very high risk of diabetes in ICA/IA2A-positive relatives. Testing for IA2A/IA2betaA compares favourably with the IVGTT in identifying a subgroup of autoantibody-positive relatives at increased risk. IA2betaA determination should be added to screening protocols of future intervention trials.