Diabetes and Kidney Disease – Prevention, Symptoms & Treatment
What are the kidneys and what do they do?
The kidneys are bean shaped organs which are located in the back of the abdominal cavity. The majority of people have two kidneys which are located on either side of the spine just beneath the rib cage posteriorly. They have many functions and a few of the major ones are to:
- Extract waste from the blood
- Balance body fluids and electrolytes
- Produce urine
- Produce hormones which control red blood cell production, bone metabolism and calcium balance
How does diabetes affect the kidneys?
When a person has diabetes this means that the average blood glucose (sugar) levels are higher than normal. This phenomena causes damage to the many vessels that exist in the kidney, and the lining of the vessels become leaky to proteins. It has also been found that the pressure inside these vessels also becomes raised which causes more damage to the structural units of the kidney in the cortex (as shown in the diagram above) which is called the glomerulus.
This damage in the earliest stages manifests as spilling of proteins into the urine (proteinuria / albuminuria). Although diabetes is not the only cause of proteins in the urine it is one of the earliest signs which can be easily picked up by a urine test. The amount of protein spillage should be quantified by running the urine through a special machine either in your doctor’s office or at one of the many laboratories in Barbados.
If I have diabetes will I end up with damaged kidneys?
This is not necessarily the case at all. Patients with Type 1 diabetes don’t usually have evidence of kidney damage at the time of diagnosis and if present another contributing factor is likely. Patients with Type 2 Diabetes may have it at the time of diagnosis simply because we know that many of these persons may have had diabetes for many years before it is actually diagnosed. This is why it is important to have yourself screened for diabetes if you are at risk for it, and to have your kidney function assessed soon after diagnosis.
It is important to know all people spill a little bit of proteins into the urine. However if that value is consistently raised in the absence of a urinary infection or other explainable cause, the chances that your kidney are being affected by your diabetes are much higher.
There are 5 (five) stages of Diabetic Kidney disease. In the very early stages with the correct interventions the damage may be reversible, but if left undiagnosed or not properly treated, the kidney damage will move into an irreversible progressive stage. However it has been shown that the rate of progression can be considerably slowed with interventions which will be discussed.
In essence it is best to prevent kidney disease rather than worrying about it after it has started. Prevention can be achieved by:
- Preventing pre-diabetes and diabetes through healthy lifestyle choices.
- Being screened for diabetes if you are at risk.
- Getting early screening for kidney disease. Your risk of developing kidney problems is higher if your diabetes is poorly controlled, if you are hypertensive or if there is a family history of kidney disease.
How do I check to see if my kidneys have been affected?
Go to your doctor and ask them to do a urine protein test (microalbumin or urine microalbumin to creatinine ratio) and a blood test (urea and creatinine). It is important to know that changes in the urine test occur before abnormalities in the blood test occur. This is why excess proteins in the urine is the earliest sign that can be easily detected, that there might be a problem with the kidneys. This should form part of your annual check-up as a person with diabetes.
Is my kidney dysfunction reversible?
As said before if significant protein spillage is picked up early yes this can be reversible with the correct measures:
- Excellent blood sugar control
- Good blood pressure control is critical. The blood pressure should be less than 130/80 mmHG. Some authorities may even recommend lower blood pressure targets. Any elevated blood pressure causes further damage to already susceptible kidneys.
- Special medications as will be mentioned.
Are there any treatments available if my kidneys are damaged?
The measures listed above are the best known measures for treatment.
Use of special medications called ACE (angiotensin converting enzyme) inhibitors or AT (angiotensin receptor) blockers. Although these are blood pressure lowering medications they have a beneficial effect in reversing or delaying the decline in renal function through a separate mechanism. This is why for example, you may not be known to have hypertension but it may be recommended to you if you have evidence of kidney dysfunction.
If your kidney disease is more advanced renal replacement options such as Dialysis (peritoneal dialysis and hemodialysis) and Kidney Transplant do exist.
Are there foods or medications I should be careful about using?
This is highly dependent on the stage of the kidney disease. Most persons can eat a normal healthy diet, however when disease is advanced certain foods may need to be avoided. However this should be discussed with your doctor or dietician. Likewise medications should be discussed with your doctor or pharmacist, as some medications may need to be avoided, or the dose may need to be adjusted based on the degree of renal impairment.
Are there any other important things to know?
There are many important things to know all of which cannot be covered in this session. However it must be stated that the risk of having a cardiovascular (e.g. angina and heart attacks) or cerebrovascular (e.g. transient ischemic event or strokes) events rises greatly in presence of diabetic kidney disease. It is therefore important to control other factors that contribute to this. Good lipid control in additional to blood pressure control is essential. Use of low dose protective aspirin may also be indicated.
If there is the presence of other complications related to diabetes such as neuropathy (nerve damage), retinopathy (changes to the back of the eye), or peripheral vascular disease the chances of having impaired kidney function is much higher. So ensure you discuss having regular checks for your kidney with your healthcare provider.
Are there any final notes?
With good early care this can be prevented. Even if you have a diagnosis of kidney disease with the right treatments or interventions progression can be delayed. Take the time to get to know more about diabetes and how you can take good care of yourself to avoid complications. Don’t believe every horror story you hear, get the right information from your healthcare provider.
Written by Dr. Diane Brathwaite from The Barbados Diabetes Foundation.