You may or may not know this, but diabetes is a major risk factor for kidney disease – around 30% of people with type 1 diabetes and 10-40% of those with type 2 diabetes will go on to experience kidney failure.
However it is new research that has found that even before a diabetes diagnosis, higher-than-normal blood sugar levels could be causing kidney damage, i.e. prediabetes may be a precursor to kidney disease.
Study coauthor Dr. Toralf Melsom, of the Department of Nephrology at University Hospital of North Norway, and colleagues published their findings in the American Journal of Kidney Disease.
Around 1 million people in Australia have prediabetes, a condition diagnosed when blood sugar levels that are higher than normal but not high enough to be diabetes.
Someone with prediabetes is likely to be diagnosed with type 2 diabetes within 10 years unless they change their diet and exercise regime.
For this latest study, the team measured the glomerular filtration rate (GFR), fasting glucose (FG) levels and/or HbA1c levels of 1,324 adults aged 50-62 in order to gain a better understanding of whether prediabetes is linked to kidney damage.
In the study, the presence of prediabetes among study participants was assessed at the beginning of the study and subjects were followed-up for a median of 5.6 years. 595 of the participants had prediabetes.
After adjusting for participants’ lifestyle and use of medications, the researchers found those with prediabetes had a higher mGFR during follow-up than those without prediabetes – a sign of hyperfiltration in the kidneys.
What is more, the researchers found that high FG levels at baseline among these subjects were associated with high levels of the protein albumin in the urine during follow-up – an early sign of kidney disease.
Dr. Melsom said, “Our research shows that the pathological process of kidney injury caused by elevated blood glucose levels starts in prediabetes, well before the onset of diabetes.
“[This means] prediabetes may be a target for early intervention to prevent chronic kidney disease (CKD) caused by hyperglycemia.
“If a patient has borderline elevated glucose levels found by their primary physician they should start lifestyle changes with respect to diet and physical activity to preventing diseases like diabetes and kidney disease”.