The ramifications of the effects of diabetes on the kidney and the relationships of renal disease to the complications of diabetes are manifold, and several recent studies have addressed important aspects of the implications and the management of diabetic kidney disease (DKD).
An estimate of the prevalence of DKD among persons with type 1 diabetes (T1D) was made based on the National Health and Nutrition Examination Survey (NHANES) database of 19 225 adults in the United States from 2015 to 2018; 47 had T1D, among whom 20 had estimated glomerular filtration rate (eGFR) ≤60 mL/min/1.73 m2 or urine albumin/creatinine ratio (UACR) ≥30 mg/g, allowing estimates of 1 202 739 adults in the United States with T1D and a weighted estimate that 21.5% of people with T1D in the United States have DKD.1 A report from the Centers for Disease Control Wide-Ranging Online Data for Epidemiologic Research database mortality statistics from 1999 to 2020 reflected the dramatic increase in mortality associated with DKD; more than 500 000 deaths were reported among adults with DKD during this period, with an age-adjusted annual mortality rate per 100 000 persons of approximately 2.0 in 1999–2005, increasing to approximately 4.0 in 2007–2010, but then to 22.0 in 2012–2019 and to 25.0 in 2020.2 In an analysis suggesting interrelationships between DKD and cognitive function (CF), among 2977 people with type 2 diabetes (T2D) in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) memory in diabetes trial, there was a greater decline over 40 months in CF with standard than with intensive glycemic treatment among those with urine albumin <0.4 mg/dL, whereas those with higher levels of albuminuria had no evidence of benefit with intensive treatment, and for those with eGFR < 60, CF decline was greater with intensive than with standard glycemic treatment. Similarly, CF decline was greater with standard than intensive glycemic treatment in the subset age <60 years, suggesting that T2D with better renal function and lower age might particularly benefit from more intensive glycemic treatment.3 There may be a different relationship between age and renal outcome with intensive lifestyle intervention (ILI); in a 12-year follow-up of the Look AHEAD (Action for Health in Diabetes) trial, prespecified analysis of the relationship between the ILI and age showed that among 5112 participants with baseline eGFR ≥ 45, those aged >60 years at baseline randomized to ILI had a 25% lower likelihood of eGFR decreasing to <45 mL/min/1.73 m2, whereas this was not seen in the younger participants.4
The optimal blood pressure treatment target is still not certain. The 11 255-person Effects of Intensive Systolic Blood Pressure Lowering Treatment in Reducing Risk of Vascular Events (ESPRIT) trial included 4359 persons with diabetes with systolic b