By James Myhre & Dennis Sifris, MD
Published on November 08, 2022
Medically reviewed by Kashif J. Piracha, MD
Diabetes and chronic kidney disease (CKD) are common conditions affecting 11%1 and 17%2 of adults in the United States, respectively. Although each can occur on its own, they can also occur together as comorbid (coexisting) conditions.
On the one hand, diabetes can give rise to CKD due to the long-term damage it can inflict on blood vessels throughout the body, including those of the kidneys.3
Centers for Disease Control and Prevention. Diabetes and chronic kidney disease.
On the other, there is increasing evidence that CKD can cause diabetes due to the buildup of waste from the malfunctioning kidneys, which, in turn, affects insulin production.4 How the body produces or responds to insulin (a hormone that allows cells to take in sugar for energy) is key to the development of diabetes.
This article takes a closer look at the connection between diabetes and chronic kidney disease, including how one increases the risk of the other. It also explores treatment options and things you can do to prevent this all-too-common comorbidity.
Definitions
For the purposes of this article, "male" refers to people born with penises and "females" refers to people born with vaginas irrespective of which gender or genders they identify with or if they identify with no gender at all.
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Connection Between Diabetes and Chronic Kidney Disease
Both diabetes and CKD are chronic illnesses, meaning that they are persistent and typically progressive. Over time, they can cause damage to multiple organs, leading to such comorbid conditions as hypertension (high blood pressure), hyperlipidemia (high cholesterol), and cardiovascular (heart) disease.
Diabetes and CKD can also give rise to each other, particularly when the diseases are advanced or poorly controlled.
How Diabetes Causes CKD
Diabetes is a group of diseases that causes high blood sugar (glucose). When blood sugar levels are high—referred to as hyperglycemia—they reduce levels of a chemical in the blood called nitric oxide.
The persistent depletion of nitric oxide, which the body uses to regulate blood pressure, can cause vessels to lose their elasticity and narrow over time. This causes hypertension, a common condition in people with diabetes.5
High blood pressure is a problem because it increases the force of blood through vessels, which can severely damage artery walls.6 High blood sugar can also directly damage the lining of blood vessels by exposing them to persistent inflammation and oxidative stress.7
When this occurs in the kidneys, millions of tiny filtering units called nephrons can be irreversibly damaged. This prevents the kidneys from filtering waste out of your blood, leading to CKD.3
CKD caused by diabetes is aptly referred to as diabetic kidney disease.8 CKD can result from both type 1 diabetes, an autoimmune form of diabetes, and type 2 diabetes, the type largely linked to lifestyle factors such as diet and obesity.3
Current Statistics
One in three adults with diabetes has CKD, according to the Centers for Disease Prevention (CDC). Every 24 hours in the United States, 170 adults with diabetes begin treatment for kidney failure.3 Kidney failure, in which the kidney can no longer remove waste or excess fluid from the blood, tends to occur 20–30 years after the onset of diabetes.9
Complications of Untreated Diabetes
How CKD Causes Diabetes
CKD is characterized by the progressive loss of kidney function. Many things, including kidney injury, can cause CKD, but the three most common causes are hypertension, heart disease, and diabetes.10
Recent research suggests that people with non-diabetic kidney disease run an increased risk of type 2 diabetes due to the buildup of a waste product called urea in the blood.4
Urea is a natural byproduct of metabolism that the kidneys can usually remove from the body in urine. However, when kidney function is impaired, urea can start to accumulate. High urea levels can directly affect beta cells in the pancreas, which are responsible for making, storing, and secreting insulin into the bloodstream.4
Insulin is the hormone tasked with regulating blood sugar in the body, and the depletion of this hormone can contribute to the onset of diabetes in people with CKD.
It is unclear if high blood urea can do this on its own or simply increases the risk in those already vulnerable to type 2 diabetes. Either way, the link between non-diabetic kidney disease and diabetes remains exceptionally high.
Diabetes and Non-Diabetic Kidney Disease
A 2020 study in the Clinical Kidney Journal reported that among 832 adults living with type 2 diabetes, nearly half (49.6%) had non-diabetic kidney disease.11
Risk Factors for Diabetes and Kidney Disease
Risks
The association between diabetes and chronic kidney disease is well established. Even so, having diabetes doesn't automatically mean that you will get CKD, and having CKD doesn't automatically mean you will get diabetes. With that said, the risk of comorbidity increases if the diseases are poorly controlled.
Other risk factors can contribute to the onset of CKD in people with diabetes, some of which are modifiable (meaning you can change them) and others which are not.
Common risk factors for diabetic kidney disease include:12
Older age
Uncontrolled high blood sugar
Uncontrolled high blood pressure
Uncontrolled high cholesterol
Smoking
Obesity
Having diabetes for a long period
Having diabetic retinopathy (diabetes-related eye disease)
A family history of diabetes and kidney disease
Complications of Diabetic Kidney Disease
Type 2 diabetes is the leading cause of end-stage kidney disease, for which dialysis or kidney transplant are the only treatment options.9 Diabetic kidney disease is also linked to an increased risk of death overall, particularly from heart disease.13
The link between non-diabetic kidney disease and type 2 diabetes is far less clear. In some cases, they may develop independently of each other. Even so, there are certain factors that can speed the progression of CKD and potentially contribute to the onset of diabetes.
Common modifiable and non-modifiable risk factors for CKD progression include:14
Male sex
Smoking
Poor sleep quality
Uncontrolled high blood pressure
Having cardiovascular diseases like atherosclerosis (hardening of the arteries) or atrial fibrillation (irregular and often rapid heartbeat)
Racial Disparities and CKD Progression
Latinx and Black people in the United States experience up to a twofold increased risk of CKD progression compared to White people.14 Though genetics play a part (as seen with the APOL1 gene, which increases the risk of CKD progression in Black people),15 higher poverty rates and poorer access to healthcare limit their ability to manage CKD effectively and avoid progression.14
How Long Can You Live With Chronic Kidney Disease?
Treatment and Management of Diabetes and Chronic Kidney Disease
Although there is no cure for either diabetes or chronic kidney disease, both can be managed with lifestyle changes and medications to slow their progression and prevent long-term complications.
Type 1 and Type 2 Diabetes
The primary aim of both type 1 and type 2 diabetes is to maintain your blood sugar within the normal range to avoid disease progression and complications. The treatment plan can vary by the type and stage of diabetes you are living with, but it typically involves:
Healthy eating: This involves a high intake of fruits, vegetables, lean proteins, and whole grains and reducing sugary and highly processed foods.16
Exercise: Experts recommend at least 150 minutes of moderate-level physical activity per week to help lower your blood sugar. Exercise also helps if you are overweight or have obesity.17
Insulin therapy: This typically involves insulin injections to help normalize blood sugar whenever your glucose monitor says that levels are too high.18
Oral medications: These include medications like Glucophage (metformin), Glucotrol (glipizide), Actos (pioglitazone), Januvia (sitagliptin), and Invokana (canagliflozin) that either slow the production of glucose, increase the production of insulin, or help the body better utilize insulin.18
How Type 2 Diabetes Is Treated
Chronic Kidney Disease
The treatment of chronic kidney disease varies by cause. If diabetes is the cause, the focus would be on maintaining glycemic control and treating disease complications (such as high blood pressure or high cholesterol).
The treatment plan for CKD also varies by the stage of the disease and how functional your kidneys are. Options include:19
High blood pressure medications: Antihypertensive drug options include angiotensin-converting enzyme (ACE) inhibitors and diuretics ("water pills"). Diuretics can also help treat fluid buildup in the lower legs, which is known as edema and is common in people with advanced CKD.
Cholesterol-lowering drugs: Statin drugs like Lipitor (atorvastatin) and Pravachol (pravastatin) are used in tandem with diet to help normalize cholesterol levels in the blood.
Iron supplements: These may be prescribed with vitamin B12 or folate supplements to increase your red blood cell count and relieve anemia. In severe cases, erythropoietin-stimulating drugs may be given either by injection or intravenously (into a vein) in tandem with iron supplements.
Calcium and vitamin D supplements: Calcium and vitamin D can help keep bones strong and prevent fractures caused by the depletion of these nutrients by CKD.
Phosphate binders: Drugs like Renvela (sevelamer) help lower phosphate levels in the blood and protect blood vessels from damage caused by calcification (the abnormal deposit of calcium).
Low-protein diet: A diet low in protein is necessary if your kidney function is significantly impaired. This prevents the buildup of urea caused by protein metabolism (the breakdown of protein).
How Chronic Kidney Disease Is Treated
Prevention
Diabetes and chronic kidney disease are not always avoidable. Type 1 diabetes, for example, is caused by a malfunctioning immune system,20 and, even with type 2 diabetes, genetic factors may predispose you to the disease.21 The same applies to CKD, for which there are risk factors you can't change (like race or family history).22
That said, there are effective ways to reduce your risk of diabetes and CKD, many of which overlap.
How to Prevent Diabetes
Lose excess weight.
Be more physically active.
Follow a healthy eating plan.
Avoid sugary and highly processed foods.
Stop smoking.
How to Prevent CKD
Lose excess weight.
Be more physically active.
Follow a healthy eating plan.
Avoid sugary and highly processed foods.
Manage your diabetes.
Manage your blood pressure.
Summary
Diabetes and chronic kidney disease (CKD) are closely linked. On the one hand, uncontrolled diabetes can cause CKD by damaging blood vessels and tiny filters called nephrons in the kidneys. On the other, CKD may contribute to the onset of diabetes due to the buildup of waste products that suppress insulin production.
Eating a healthy diet, avoiding sugary foods, exercising regularly, and maintaining an ideal weight can go a long way toward preventing diabetes and CKD, individually and together.
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