High Calcium Levels: Causes, Symptoms, and Health Risks

Calcium is an essential mineral vital for maintaining strong bones, facilitating nerve transmission, and ensuring proper muscle function. While a deficiency can lead to significant health issues, excessively high levels of calcium in the blood—a condition known as hypercalcemia—can also pose serious health risks. Understanding the causes, recognizing the symptoms, and knowing the potential complications are crucial for managing this condition effectively.

What is Hypercalcemia?

Hypercalcemia occurs when the concentration of calcium in your blood rises above the normal range. Calcium plays a critical role in numerous bodily functions, and its levels are tightly regulated by several hormones, most notably the parathyroid hormone (PTH) and calcitonin. When this regulatory system is disrupted, calcium can accumulate in the blood, leading to a variety of health problems that can range from mild to severe.

Primary Causes of High Calcium Levels

Several underlying medical conditions can cause hypercalcemia. Identifying the root cause is the most important step in determining the appropriate treatment plan.

Overactive Parathyroid Glands (Hyperparathyroidism): This is the most common cause of hypercalcemia. The four small parathyroid glands, located behind the thyroid gland in the neck, produce parathyroid hormone (PTH), which helps regulate calcium, vitamin D, and phosphorus levels in the blood and bones.
- Primary Hyperparathyroidism: This condition occurs when one or more of the parathyroid glands become enlarged or develop a noncancerous growth (adenoma). The affected gland produces excessive amounts of PTH, which signals the body to release too much calcium from the bones into the bloodstream. It also increases calcium absorption from food in the intestines and reduces the amount of calcium excreted by the kidneys.
- Secondary Hyperparathyroidism: This form arises as a response to another medical condition that causes low calcium levels, such as chronic kidney failure. The parathyroid glands become overactive to compensate, but if the underlying issue is resolved (like through a kidney transplant), the glands may continue to produce excess PTH, leading to hypercalcemia.
Cancer: Cancer is the second leading cause of hypercalcemia, particularly in hospitalized patients. Certain types of cancer can elevate blood calcium levels in several ways:
- Bone Metastases: Cancers that spread to the bones, such as breast cancer, prostate cancer, and multiple myeloma, can destroy bone tissue, causing calcium to be released into the blood.
- PTH-related Peptide (PTHrP) Production: Some malignant tumors (e.g., lung cancer, kidney cancer) produce a protein called PTH-related peptide. This protein mimics the action of PTH, leading to elevated calcium levels even without direct bone involvement.
Dehydration: Severe dehydration leads to a decrease in the fluid portion of the blood, which concentrates the calcium already present. This results in a temporary, mild form of hypercalcemia that typically resolves once fluid levels are restored.
Genetic Factors: In rare cases, a genetic mutation can lead to hypercalcemia. Familial hypocalciuric hypercalcemia (FHH) is an inherited disorder that causes elevated calcium levels in the blood due to faulty calcium-sensing receptors in the body.
Prolonged Immobilization: Being bedridden or immobilized for an extended period can cause bones to demineralize and release calcium into the bloodstream. This is more common in individuals with pre-existing conditions like Paget's disease of bone.

Symptoms of High Calcium Levels

The symptoms of hypercalcemia can vary widely depending on the severity and duration of the condition. Mild cases may produce no noticeable symptoms, while severe cases can be life-threatening.

Mild to Moderate Symptoms:

Kidney-related issues: Excessive thirst, frequent urination, and kidney stones.
Digestive problems: Nausea, vomiting, constipation, and abdominal pain.
Musculoskeletal issues: Bone pain, muscle weakness, and aches.
Neurological symptoms: Fatigue, lethargy, confusion, and mild memory loss.

Severe Symptoms:

Extreme confusion, disorientation, or difficulty thinking.
Depression or irritability.
Severe muscle pain and weakness.
Cardiac arrhythmia (irregular heartbeat) and other heart problems.
Loss of consciousness or coma.

Health Risks and Long-Term Complications

If left untreated, chronic hypercalcemia can lead to serious and sometimes irreversible health complications.

Osteoporosis: Paradoxically, while there is too much calcium in the blood, the bones are losing it. This can lead to bone thinning, increasing the risk of fractures.
Kidney Stones: Excess calcium in the urine can form crystals that may aggregate into painful kidney stones.
Kidney Failure: Severe or prolonged hypercalcemia can damage the kidneys, impairing their ability to filter blood and excrete waste products effectively. This can eventually lead to chronic kidney disease or complete kidney failure.
Cardiovascular Disease: High calcium levels can affect the electrical system of the heart, leading to abnormal heart rhythms and other cardiovascular problems.
Nervous System Problems: Severe hypercalcemia can cause confusion, dementia, and in extreme cases, coma.

Diagnosis and When to Seek Medical Attention

Hypercalcemia is typically diagnosed through a routine blood test that measures calcium levels. If your results are high, your doctor will likely order further tests to determine the underlying cause, such as:

Blood tests to check PTH levels, vitamin D, and kidney function.
Urine tests to measure calcium excretion.
Imaging studies, such as an ultrasound of the neck or a bone density scan, to check for parathyroid abnormalities or bone loss.

If you experience persistent symptoms like excessive thirst, frequent urination, unexplained nausea, or bone pain, it is important to consult a healthcare professional for a proper diagnosis.

Conclusion

Understanding the causes and risks of high calcium levels is the first step toward proactive health management. While the condition can be serious, it is often manageable with timely diagnosis and appropriate treatment aimed at the underlying cause. Regular health check-ups and blood tests are essential for early detection and preventing long-term complications.

At AMPATH Labs, we are committed to providing accessible and accurate diagnostic services. Our state-of-the-art facilities and certified professionals ensure you receive reliable results to guide your healthcare decisions.