hyperfiltration was a strong risk factor for developing elevated UACR . Other risk factors included glycated hemoglobin levels , or HbA1c , which indicates excessive sugar in the bloodstream .
That was expected , but they demonstrated other important risk factors as well : hypertension , serum uric acid and various parameters of beta cell function .
“ These risk factors are potentially modifiable ,” says Dr . Bjornstad . “ That ’ s important , because it means you can potentially target them with interventions .”
“ The level of detail in these data lets us tease out associations ,” says Dr . Zeitler . “ If one of these kids has neuropathy , what meds are they on ? What was their HbA1c over time ? If you look at kids who develop neuropathy , what was the difference between them and kids who didn ’ t ? We can figure that out .”
The TODAY Study Group is in the process of figuring that out right now , starting with a suite of six papers , including the nephropathy paper led by Dr . Bjornstad ( 3 ), appearing in Diabetes Care . Those papers will take a first look at an array of associations : the impact of cholesterol on retinopathy , the impact of pregnancy , as well as ethnic and racial associations and social determinants of health . Dr . Bjornstad ’ s paper , for example , found that female participants and participants of Hispanic heritage had a heightened risk of hyperfiltration .
The question now is why .
WIDENING AND DEEPENING THE DATA
“ This disorder , in the U . S . anyway , disproportionately affects minorities and other socially disadvantaged populations ,” says Dr . Zeitler . “ But the reasons are very complex . When you say Hispanic people are more likely to get kidney disease , is that because of ancestry ? Poverty ? Lack of access to treatment ? Hypertension ?”
The factors at play
One of the most pressing problems with youth-onset type 2 diabetes is the lack of treatment options that work . One intervention that has a pronounced effect , however , is bariatric surgery .
In fact , when Dr . Bjornstad compared rates of diabetic kidney disease of participants in TODAY to participants in Teen-LABS , the largest-ever study of bariatric surgery in adolescents ( 5 ), the results were dramatic ( 6 ). Five years out from surgery , participants in Teen-LABS had 16-fold lower odds for hyperfiltration and 27-fold lower odds for elevated UAE than TODAY participants .
“ Clearly bariatric surgery protects the kidney , but weight loss surgery is not for everyone ,” Dr . Bjornstad says . “ We need to understand now how surgery protects . Attaining a normal BMI is part of it , but there are other factors at play .”
Dr . Bjornstad ’ s ongoing study , IMPROVE-T2D , seeks to understand those factors . So far , they ’ ve enrolled 16 of 30 participants , all of whom have type 2 diabetes and qualify to undergo bariatric surgery per clinical indications . IMPROVE-T2D integrates state-of-the-art physiology testing with MRI and kidney biopsies to understand how bariatric surgery mitigates diabetic kidney disease on a molecular level .
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