ORLANDO – A new analysis of more than 1.5 million U.S. subjects with diabetes found that chronic kidney disease (CKD) is much more common in type 2 diabetes mellitus (T2DM) than in type 1 diabetes mellitus (T1DM) – 44% vs. 32%, respectively. The research also provides more evidence that albumin testing can provide crucial warning signs of future kidney trouble.
“Our data suggest – but don’t really prove – that there’s a lot more eGFR testing than there is albumin testing,” said nephrologist and study coauthor Michael Cressman, DO, of Covance, the drug development business of LabCorp, in an interview at the annual scientific sessions of the American Diabetes Association. “It is very important to measure albumin in the urine in order to identify patients who are at highest risk of progressive renal disease. There you identify people for whom you really want to maximize all the available treatments.”
According to the study, previous research has estimated that 25% of U.S. adults with diabetes have CKD (eGFR less than 60 ml/min per 1.73m2 or an albumin to creatinine ratio equal to or greater than 30 mg/g), but the difference in rates between T1DM and T2DM has been unclear.
Researchers analyzed LabCorp laboratory data on blood from for 48,036 adults with T1DM and 1,461,915 with T2DM. The analysis included ACR and CKD-EPI calculator for eGFR measurements from 2014-2017.
The researchers tracked declines in eGFR in patients who had more than three eGFR readings over at least 1 year.
Researchers found that the rate of CKD was 40% higher in patients with T2DM than it was in those with T1DM (44% vs. 32%, respectively; P less than .001), as was the prevalence of subjects considered to be at high or very high risk (18% vs. 12%, respectively; P less than .001).
These findings didn’t surprise Dr. Cressman, who said the higher ages of subjects with T2DM could explain the gap since they were more likely to have been exposed to hypertension for longer amounts of time.
Researchers also reported that the median eGFR decline (ml/min per year) was especially high in those with macroalbuminuria: –3.80 in T1DM and –3.58 in T2DM.
“Although MA [macroalbuminuria] is uncommon and most frequently observed in patients with normal or only mildly reduced eGFR, it was a potent predictor of eGFR decline in both T1DM and T2DM,” the researchers wrote.
“While it’s been known for a while that it’s bad to have albumin, this is more of a strong reinforcing piece of data,” Dr. Cressman said. “When you read about these things and it’s an epidemiological study or a clinical trial, it kind of loses its flavor. These are actual patients. A doctor could look at this data and say, ‘I ought to be checking this [albumin].’ It’s sort of an obvious rationale for what the guidelines say.”
No study funding was reported. Dr. Cressman reported employment by Covance. Other study authors variously report no disclosures or employment by Covance and its parent company LabCorp and stock/shareholding in LabCorp.
SOURCE: Cressman M et al. ADA 2018, .