Aims/hypothesis Against a background of a near-universally increasing incidence of childhood type 1 diabetes, recent reports from some countries suggest a slowing in this increase. Occasional reports also describe cyclical variations in incidence, with periodicities of between 4 and 6 years. Methods Age/sex-standardised incidence rates for the 0- to 14-year-old age group are reported for 26 European centres (representing 22 countries) that have registered newly diagnosed individuals in geographically defined regions for up to 25 years during the period 1989–2013. Poisson regression was used to estimate rates of increase and test for cyclical patterns. Joinpoint regression software was used to fit segmented log-linear relationships to incidence trends. Results Significant increases in incidence were noted in all but two small centres, with a maximum rate of increase of 6.6% per annum in a Polish centre. Several centres in high-incidence countries showed reducing rates of increase in more recent years. Despite this, a pooled analysis across all centres revealed a 3.4% (95% CI 2.8%, 3.9%) per annum increase in incidence rate, although there was some suggestion of a reduced rate of increase in the 2004–2008 period. Rates of increase were similar in boys and girls in the 0- to 4-year-old age group (3.7% and 3.7% per annum, respectively) and in the 5- to 9-year-old age group (3.4% and 3.7% per annum, respectively), but were higher in boys than girls in the 10- to 14-year-old age group (3.3% and 2.6% per annum, respectively). Significant 4 year periodicity was detected in four centres, with three centres showing that the most recent peak in fitted rates occurred in 2012. Conclusions/interpretation Despite reductions in the rate of increase in some high-risk countries, the pooled estimate across centres continues to show a 3.4% increase per annum in incidence rate, suggesting a doubling in incidence rate within approximately 20 years in Europe. Although four centres showed support for a cyclical pattern of incidence with a 4 year periodicity, no plausible explanation for this can be given.

Summary: Diabetes (DM) as well as obesity, due to their increasing incidence, were recognized as epidemic by the World Health Organization. Obesity is involved not only in the aetiopathogenesis of the most common worldwide type of DM—type 2 diabetes—but also in the development of its complications. There is also increasing scientific evidence regarding the role of obesity and overweight in type 1 diabetes. Weight gain may be considered as a complication of insulin treatment but also reveals significant pathophysiological impact on various stages of the disease. Another very important aspect related to DM as well as obesity is the microbiome, which is highly variable. The function of the gut microflora, its interaction with the whole organism, and its role in the development of obesity and type 1 diabetes as well as type 2 diabetes are still not fully understood and subject of ongoing investigations. This review presents a summary of recently published results concerning the relation of obesity/overweight and DM as well as their associations with the microbiome.

Summary: The level of glycaemic control necessary to achieve optimal short‐term and long‐term outcomes in subjects with type 1 diabetes mellitus (T1DM) typically requires intensified insulin therapy using multiple daily injections or continuous subcutaneous insulin infusion. For continuous subcutaneous insulin infusion, the insulins of choice are the rapid‐acting insulin analogues, insulin aspart, insulin lispro and insulin glulisine. The advantages of continuous subcutaneous insulin infusion over multiple daily injections in adult and paediatric populations with T1DM include superior glycaemic control, lower insulin requirements and better health‐related quality of life/patient satisfaction. An association between continuous subcutaneous insulin infusion and reduced hypoglycaemic risk is more consistent in children/adolescents than in adults. The use of continuous subcutaneous insulin infusion is widely recommended in both adult and paediatric T1DM populations but is limited in pregnant patients and those with type 2 diabetes mellitus. All available rapid‐acting insulin analogues are approved for use in adult, paediatric and pregnant populations. However, minimum patient age varies (insulin lispro: no minimum; insulin aspart: ≥2 years; insulin glulisine: ≥6 years) and experience in pregnancy ranges from extensive (insulin aspart, insulin lispro) to limited (insulin glulisine). Although more expensive than multiple daily injections, continuous subcutaneous insulin infusion is cost‐effective in selected patient groups. This comprehensive review focuses on the European situation and summarises evidence for the efficacy and safety of continuous subcutaneous insulin infusion, particularly when used with rapid‐acting insulin analogues, in adult, paediatric and pregnant populations. The review also discusses relevant European guidelines; reviews issues that surround use of this technology; summarises the effects of continuous subcutaneous insulin infusion on patients' health‐related quality of life; reviews relevant pharmacoeconomic data; and discusses recent advances in pump technology, including the development of closed‐loop ‘artificial pancreas’ systems. © 2015 The Authors. Diabetes/Metabolism Research and Reviews Published by John Wiley & Sons Ltd.