Kidney Problems

Chronic kidney disease (CKD) means the kidneys have been damaged for more than three months. Common causes include diabetes, high blood pressure, kidney inflammation, and other health problems.

CKD can sometimes be slowed or prevented with proper treatment. About 10% of older adults have CKD. It affects about 20% of adults with high blood pressure and 35% of people with diabetes.

Doctors monitor CKD with blood tests, including a basic metabolic panel (BMP). One important number is the glomerular filtration rate (GFR). The GFR shows how well the kidneys are cleaning the blood.

Five stages of CKD based on the GFR:

• Stages 1 and 2 (Mild): GFR is above 60. Kidney function is still fairly good.
• Stage 3 (Moderate): GFR is below 60. A kidney specialist (nephrologist) is often consulted.
• Stage 4 (Severe): Kidney function is very low. A nephrologist helps manage problems caused by CKD.
• Stage 5 (Kidney failure): The kidneys no longer work well enough to meet the body’s needs. Dialysis (a machine that cleans the blood) is often needed.

People with CKD have a higher risk of:

• Heart disease
• Anemia (low red blood cell count)
• Side effects from medications
• Bone disease, such as osteoporosis
• Depression and tiredness
• Nutrition problems

Electrolytes are minerals in the blood, such as sodium (salt) and potassium. An imbalance happens when these levels are too high or too low.

Hyponatremia (Low Sodium)

Hyponatremia means the sodium level in the blood is too low. It can be caused by:

• An underactive thyroid
• A very low-salt diet
• Illness that changes hormone levels
• Too much fluid in the body, which dilutes (waters down) sodium
• Certain medications, such as:
  • NSAIDs (pain relievers)
  • Thiazide diuretics (“water pills”)
  • Some antidepressants

Up to 25% of older adults in the hospital may have low sodium. Even mild low sodium can cause problems with attention and thinking.

Treatment may include limiting fluids and using medications to help bring sodium levels back to normal.

Hypernatremia (High Sodium)

Hypernatremia means the sodium level in the blood is too high. Causes include:

• Not drinking enough fluids
• Trouble swallowing
• Illnesses such as infections with fever or dementia
• Some medications, such as diuretics
• Very high blood sugar levels that lead to dehydration

Treatment usually involves drinking more fluids or receiving fluids through a vein.

Hyperkalemia (High Potassium)

Hyperkalemia can be caused by:

• certain medications, such as NSAIDs, some heart medications, and some diuretics
• Some hormone problems

Treatment may include medications, extra fluids, dialysis (a machine that cleans the blood), or hospital care in severe cases.

Fluid imbalances 

Fluid problems are also common in older adults. These can lead to dehydration (not enough fluid), swelling, or other serious health problems.

Kidney stones are small, hard pieces of material that form in one or both kidneys. They can happen because of dehydration, infection, or stress on the kidneys.

Nephrotic syndrome is common in older adults. It happens when the kidneys are damaged and allow too much protein to leak into the urine. This damage affects the part of the kidney that filters blood.

There are different types of nephrotic syndrome:

• Membranous nephropathy: The immune system attacks the kidney’s filtering parts.

• Diabetic nephropathy: Kidney damage caused by diabetes over time.

• Amyloidosis: Abnormal proteins build up in the kidneys.

• Glomerulonephritis: Swelling of the kidney’s filtering parts.

• Minimal change disease: Damage to the filtering parts that may not be seen easily on tests.

• Systemic lupus erythematosus (lupus): An autoimmune disease that can damage the kidneys.

• Monoclonal gammopathy: Kidney damage caused by abnormal proteins in the blood.

Renovascular disease affects the blood vessels that carry blood to the kidneys. When blood flow is reduced, kidney damage can occur.

• People at higher risk include:
  Older adults

• People with heart or blood vessel disease

• Smokers

• People with a history of blood clots

• People with high blood pressure or high cholesterol

Treating these health problems early can help prevent more serious kidney damage.

Acute kidney failure happens when the kidneys suddenly stop working well. This change happens quickly.

Common causes include:

• Dehydration (not drinking enough fluids or losing too much fluid from illness)

• Infection

• A blockage that prevents urine from leaving the body. This is common in older men with an enlarged prostate or in people with kidney stones.

• Surgery

• Heart failure or heart rhythm problems

• Certain medications, such as strong pain medicines, diuretics (“water pills”), antihistamines, and some antidepressants

Treating the cause quickly can often help the kidneys recover. Some people may need dialysis (a machine that cleans the blood) for a short time until their kidneys improve.

End-stage renal disease (ESRD) is the final stage of kidney disease. At this stage, the kidneys no longer work well enough to meet the body’s needs.

Older adults are at higher risk if they have long-term, uncontrolled high blood pressure, uncontrolled diabetes, or inherited kidney diseases such as polycystic kidney disease.

ESRD cannot be cured. Treatment includes dialysis (a machine that cleans the blood) or a kidney transplant. A kidney specialist (nephrologist) helps patients choose the best option based on their health and personal goals.

At any time, almost 600,000 people in the United States are being treated for ESRD. Each year, about 18,000 people receive a kidney transplant, and nearly 90,000 people with ESRD die.