Trends in diabetes incidence: a systematic review

Objective. We conducted a systematic review to assess what proportions of studies reported increasing, stable or declining trends in the incidence of diagnosed diabetes. Design Systematic review of studies reporting trends of diabetes incidence in adults from 1980 to 2017 according to PRISMA guidelines. Data sources MEDLINE, EMBASE and CINAHL and reference lists of relevant publications. Eligibility criteria We included studies of open population-based cohorts, diabetes registries, and administrative and health insurance databases, and reported on secular trends in the incidence of total diabetes or type 2 diabetes in adults. Statistical methods: We used Poisson regression and modelled data by age-group and year. Results Among the 22,833 screened abstracts, 47 studies were included, providing data on 121 separate sex- or ethnic-specific populations. The majority (90%) of the included studies reported on diagnosed diabetes. From 1960 –1989, 38% of the populations studied experienced increasing trends in incidence of diabetes, 54% had stable trends, and 8% experienced decreasing trends. In 1990–2005, diabetes incidence increased in 67% of populations, was stable in 31%, and decreased in 2%. In 2006–2014, increasing trends were reported in only 33% of populations, whereas 30% and 36% had stable or declining incidence, respectively. Conclusions The incidence of diagnosed diabetes has continued to rise in only a minority of populations studied since 2006, with over a third of populations experiencing a fall in incidence in this time-period. Preventive strategies may have contributed to the fall in the incidence of diabetes in recent years. There are limited data in low- and middle-income countries where trends in diabetes incidence may be different