Endocrine Abstracts

Introduction: Type 2 diabetes (T2D) has increased in youth and complications rates may be higher than type 1 diabetes (T1D).

Aims: To estimate the prevalence of complications and hypertension in youth with type 2 diabetes and compare complication rates between T2D and T1D.

Design and methods: Systematic review and meta-analysis of observational studies, analysed with random effects models.

Data sources: Medline and Embase (until Oct-2011), article bibliographies and contact with experts.

Eligibility criteria: Longitudinal or cross-sectional observational studies measuring incidence or prevalence of nephropathy, hypertension, retinopathy, peripheral neuropathy and/or autonomic neuropathy in youth or young adults (≤28 years) with T2D. Studies of youth with both T2D and T1D were included; where possible meta-analysis was conducted to compare complication rates. Evidence levels were assigned using the Oxford CEMB and quality assessed using the Newcastle–Ottawa scale.

Results: The final search yielded 25 studies involving 3321 youth. Overall, methodological quality was poor. Among those with T2D, median age was 14.5 years, duration 1.7 years and HbA1c 7.7%. Pooled prevalence (95% CI) for T2D was: microalbuminuria 18% (17–20%); macroalbuminuria 5% (3–7%); hypertension 28% (26–29%); retinopathy 2% (1–3%); peripheral neuropathy 2% (1–4%); and autonomic neuropathy 43% (25–63%). Compared with T1D, microalbuminuria was more common in T2D: odds ratio (OR) 3.5, 95% CI 1.6–7.8, and hypertension: OR 3.4, 95% CI 2.4–4.8. There was significant heterogeneity across studies for microalbuminuria, hypertension and nephropathy (P<0.01).

Conclusions: This is the first systematic review of complications in youth with T2D; they have higher rates of microalbuminuria and hypertension compared with T1D, despite shorter diabetes duration. There is a paucity of quality data on complications in youth with T2D. Large-scale prospective cohort studies are required to better understand their specific risk factors for microvascular complications, and to guide complications screening and treatment.

Figure 1 – Odds ratio for nephropathy prevalence in youth with type 2 vs type 1 diabetes.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.