Why kidney disease, heart disease and diabetes are connected

Carlos Zayas, MD

Nephrology

If you have heart disease or diabetes, you have a pretty high risk of also developing kidney disease. Nephrologist Carlos F. Zayas, MD, explained why kidney disease, heart disease and diabetes are connected and how you can prevent kidney disease from developing.

How are kidney disease and heart disease related?

The common link between heart disease and chronic kidney disease is hypertension, aka high blood pressure.

Blood pressure is the force your blood makes against your artery walls when your heart beats. If the force is too high, it can damage the small blood vessels in your kidneys, which means they won’t be able to filter your blood as well as they should. The general recommendation is for blood pressure to be kept below 140/90, but aim for a blood pressure of around 120/70 mmHg.

“Think about the heart as a magnificent and complicated pump that sends blood to these sophisticated filters called the kidneys,” said Dr. Zayas. “If the pump doesn’t send enough blood, the kidneys don’t filter very well because they’re not getting enough oxygen. When the kidneys don’t filter the blood, toxins are accumulated and make you sick, resulting in chronic kidney disease.”

Also, the water that is not excreted accumulates as fluid in your lungs, legs and abdomen, leading to congestive heart failure like symptoms. The accumulation of electrolytes like potassium can cause heart arrythmias.

How are kidney disease and heart disease related to diabetes?

Uncontrolled diabetes, both Type 1 and Type 2, is the most common cause of chronic kidney disease and kidney failure. According to the Centers for Disease Control and Prevention, (CDC), approximately 1 in 3 adults with diabetes has chronic kidney disease.

Why? Elevated sugar caused by uncontrolled diabetes can damage the kidneys over time, causing them to malfunction.

Both blood pressure and diabetes can lead to kidney disease which can also lead to heart disease. It’s a dangerous cycle with each disease making the other disease worse. “When it comes to the heart and the kidneys, each organ needs the other to be healthy,” Dr. Zayas said.

Can kidneys heal if damaged?

Possibly. If the issue that is contributing to kidney disease is caught early enough, and it is corrected, the kidney cells can recover. If the problem persists and it’s sustained, the kidneys will eventually fail.

Dr. Zayas explained it this way. The brain, kidneys and the heart have one thing common – they’re extremely sensitive to lack of oxygen. Heart attacks involve a lack of oxygen going to the heart. For the brain, a lack of oxygen is referred to as a stroke. When it happens to the kidneys over a long period of time, it can damage the kidneys and lead to total atrophy. This means if the damage or the lack of oxygen is sustained over time, the cells will die and not recover.

If you have heart disease or diabetes, how can you prevent kidney disease?

Even though kidney disease, heart disease and diabetes are connected, they’re not inevitable, even if you have a family history. Dr. Zayas said there are four main ways you can protect your heath.

Stay active. “Exercise lowers your risk of diabetes because it decreases your fat accumulation and the body’s resistance to insulin,” Dr. Zayas said. “Exercise also increases your kidneys’ ability to filter, which decreases your blood pressure and helps your heart pump better.”

About 30 minutes of moderate to strenuous cardiovascular activity five days a week is recommended. Also add some weightlifting or resistance training to prevent osteoporosis and keep your bone density at a healthy level.

Eat a balanced diet. Avoid consuming negative calories that could lead to obesity which increases your risk of insulin resistance and Type two diabetes.

Avoid too much salt. “Salt is one of those things that gives life to the food we eat, but in excessive amounts will increase your blood pressure which will lead eventually to kidney injury and kidney disease,” Dr. Zayas said.

Do not smoke. Smoking is associated with cardiovascular disease and the progression to renal disease. This includes smoking cigarettes, cigars and even marijuana.

It’s also important to see your doctor regularly for screenings that can check your blood pressure, blood sugar and kidney function. Many people who have diabetes and kidney disease don’t know they have it, but with regular screenings you can find out early and receive treatment before the conditions get worse.