Type 2 diabetes

Abstract

In the summary of their Seminar,1Chatterjee S Khunti K Davies MJ Type 2 diabetes.Lancet. 2017; 389: 2239-2251Summary Full Text Full Text PDF PubMed Scopus (1137) Google Scholar Sudesna Chatterjee and colleagues state that the incidence of type 2 diabetes “continues to rise globally”. There is no evidence to support this claim and most recent literature suggests that, in developed countries, incidence peaked sometime in the last decade and then levelled off or slightly decreased.2Geiss LS Wang J Cheng YJ et al.Prevalence and incidence trends for diagnosed diabetes among adults aged 20 to 79 years, United States, 1980–2012.JAMA. 2014; 312: 1218-1226Crossref PubMed Scopus (480) Google Scholar, 3Maruthur NM The growing prevalence of type 2 diabetes: increased incidence or improved survival?.Curr Diab Rep. 2013; 13: 786-794Crossref PubMed Scopus (57) Google Scholar, 4Tate AR Dungey S Glew S Beloff N Williams R Williams T Quality of recording of diabetes in the UK: how does the GP's method of coding clinical data affect incidence estimates? Cross-sectional study using the CPRD database.BMJ Open. 2017; 7: e012905Crossref PubMed Scopus (34) Google Scholar, 5Sharma M Nazareth I Petersen I Trends in incidence, prevalence and prescribing in type 2 diabetes mellitus between 2000 and 2013 in primary care: a retrospective cohort study.BMJ Open. 2016; 6: e010210Crossref PubMed Scopus (192) Google Scholar Incidence is more difficult to estimate than prevalence because it is more dependent on timely and accurate recording of the disease. A 2014 survey2Geiss LS Wang J Cheng YJ et al.Prevalence and incidence trends for diagnosed diabetes among adults aged 20 to 79 years, United States, 1980–2012.JAMA. 2014; 312: 1218-1226Crossref PubMed Scopus (480) Google Scholar of worldwide trends in diabetes incidence and prevalence concluded that, although reports of incidence are fairly sparse, “evidence from developing countries demonstrates increasing incidence rates from the 1980s to the 2000s with a plateau or downturn in more recent years”. Our own study4Tate AR Dungey S Glew S Beloff N Williams R Williams T Quality of recording of diabetes in the UK: how does the GP's method of coding clinical data affect incidence estimates? Cross-sectional study using the CPRD database.BMJ Open. 2017; 7: e012905Crossref PubMed Scopus (34) Google Scholar of coding of diabetes by general practitioners in the UK for 1995–2014 supported these findings. Incidence rose steeply until 2004 but then levelled off and slightly decreased. Similar trends were observed by Sharma and colleagues.5Sharma M Nazareth I Petersen I Trends in incidence, prevalence and prescribing in type 2 diabetes mellitus between 2000 and 2013 in primary care: a retrospective cohort study.BMJ Open. 2016; 6: e010210Crossref PubMed Scopus (192) Google Scholar Unsubstantiated comments on increasing incidence of diabetes sometimes appear in the media. However, it is surprising to see this statement in a Seminar in The Lancet. Diabetes is a major health problem worldwide and the recorded number of people living with diagnosed diabetes (prevalence) has certainly increased globally. However, this increase could be due to factors such as better diagnosis and reporting, together with ageing populations. It is important to distinguish between prevalence and incidence if we want to develop a better understanding of the epidemiology of this disease. I declare no competing interests. Type 2 diabetes415 million people live with diabetes worldwide, and an estimated 193 million people have undiagnosed diabetes. Type 2 diabetes accounts for more than 90% of patients with diabetes and leads to microvascular and macrovascular complications that cause profound psychological and physical distress to both patients and carers and put a huge burden on health-care systems. Despite increasing knowledge regarding risk factors for type 2 diabetes and evidence for successful prevention programmes, the incidence and prevalence of the disease continues to rise globally. Full-Text PDF Type 2 diabetesWe read with great interest the Seminar (Feb 9, 2017, p 2239)1 on type 2 diabetes by Sudesna Chatterjee and colleagues. However, we were surprised by the articles selected and believe that detailed selection criteria with the level of evidence of reported studies would have been useful to the reader. According to the research method described, we would expect other papers to be cited, including meta-analyses of randomised controlled trials that could have balanced the authors' outlook.2–6 For example, intensive glycaemic control probably has some beneficial effect on diabetic complications, such as non-fatal myocardial infarctions3–5 or retinopathy assessed with the Early Treatment Diabetic Retinopathy Study scale. Full-Text PDF Type 2 diabetes – Authors' replyWe thank A Rosemary Tate for her insightful comments on our Seminar.1 Tate indicates that there is no evidence to support the rise in global incidence of type 2 diabetes mentioned in the summary by citing a number of references published between 2014 and 2017 in the USA and UK. Full-Text PDF