The relationship between urinary albumin excretion, cardiovascular outcomes and total mortality among a large cohort of insulin-treated patients with type 2 diabetes in routine primary care practices.

ABSTRACT

BACKGROUND: Albuminuria is a recognized diagnostic and prognostic marker of chronic kidney disease and cardiovascular (CV) risk but the well-known relationship between increments in urinary albumincreatinine ratio (UACR) and CV outcomes and mortality has not been fully explored in insulin-treated patients with type 2 diabetes (T2D) in routine clinical care. METHODS: We investigated data for insulin users with T2D from UK general practices between 2007 and 2014. The UACR at the time of insulin initiation was measured and categorized as <10, 10- 29, 30-300 and >300 mg/g. Patients were followed up for 5 years or the earliest occurrence of all-cause mortality, non-fatal myocardial infarction or stroke. Cox proportional hazards models were fitted to estimate the risk of a composite of these events. RESULTS: A total of 12 725 patients with T2D (mean age 58.6 ± 13.8 years, mean haemoglobin A1c 8.7 ± 1.8%) initiating insulin therapy between 2007 and 2014 met the inclusion criteria. Compared with patients whose ACR levels at insulin initiation were <10 mg/g, the adjusted risk of the 3-point composite endpoint was 9, 30 and 98% higher in those with ACR levels between 10-29, 30-300 and >300 mg/g, respectively, after a follow-up period of 5 years. The ACR category on its own did not predict risk of all-cause mortality. CONCLUSIONS: This study shows that in patients with T2D on insulin therapy, increased urinary ACR is independently associated with an increased risk of major adverse CV events and all-cause mortality.