There are two types of Diabetes mellitus (DM)
- Type 1 usually starts in childhood or adolescence and patients require insulin injections;
- Type 2 usually starts in middle life and patients do not always require insulin.
Whichever type of DM you have, even when diabetes is controlled, the disease can lead to kidney problems. Fortunately, most people with diabetes do not develop a kidney problem that is severe enough to progress to end-stage renal disease (ESRD), requiring dialysis and/or a transplant.
Diabetes-related kidney disease accounts for 27.5% of new cases of kidney failure
The kidney can be affected in three different ways by DM (patients often have a combination).
- Diabetic nephropathy – damage to the glomeruli (the microscopic filters in the kidney)
- Renovascular disease – furring up of the artery to the kidney (the same process that causes heart attacks and strokes)
- Urinary tract infections.
DM is increasingly common, affecting about 5% of the population, with a higher occurrence amongst Black or Asian people. Obesity is thought to be a major factor in Type 2 DM.
Course of kidney disease
Diabetic kidney disease takes many years to develop. People who are developing kidney disease will have small amounts of a blood protein called albumin leaking into their urine. This first stage is called microalbuminuria. Kidney function usually remains normal during this period. As the disease progresses, more albumin leaks into the urine. This stage is called proteinuria.
As kidney damage develops, blood pressure often rises. Later on, chronic kidney disease (CKD) develops. At this stage, you may experience ankle swelling and shortness of breath (due to water in the lungs). It usually takes at least 10 years to get to this point. Dialysis may be necessary.
How do you know you have kidney disease?
People with DM should be screened regularly for kidney disease. The key markers for kidney disease are serum creatinine (and a formula called (eGFR) and the urine protein level.
Effects of high blood pressure
Both a family history of DM with complications, and the presence of hypertension (high blood pressure, BP), increase the chances of developing kidney disease in people with diabetes. Hypertension also accelerates the progress of kidney disease when it already exists.
All people with diabetes should keep their BP below 130/80
Treatment of even mild hypertension is essential for people with DM.
Preventing and slowing kidney disease
- Stopping smoking. Smoking is a health risk for everyone, but for people with diabetes the risk is even greater. Along with DM, it causes renovascular, and worsens kidney disease, as well as contributing to heart attacks and strokes. Try to give up - your GP can help.
- BP tablets. Drugs used to lower BP (to 130/80, or lower) can slow the progression of kidney disease significantly. Two types of drugs, angiotensin receptor blockers (ARB), are effective in slowing the progression of kidney disease. Patients with even mild BP or persistent microalbuminuria (first stage of diabetic kidney disease), should have low BP preferably take an ACEi or ARB.
- Other treatments. Keeping blood sugar well controlled may help, especially for those in the early stages of kidney disease. Lowering cholesterol to <5.0 mmol/L with a drug called a 'statin' may also be of benefit.
Dialysis and transplantation
When people with diabetes experience ESRD they need either dialysis or a kidney transplant. Some patients with Type 1 DM can have a 'double' (kidney-pancreas) transplant. Currently, the survival of kidneys transplanted into people with DM is about the same as the survival of transplants in people without DM (about 10-15 years). Dialysis for people with diabetes also works well in the short run.
Find out more
You can also find out more about diabetes on the following website:-