Multiple myeloma is the second most common type of blood cancer.
There are many symptoms that can develop because of multiple myeloma. One of the most common is abnormally high levels of calcium in your body, according to
Higher rates of hypercalcemia are found in people with multiple myeloma than in any other condition.
According to a
This article explores why hypercalcemia develops so frequently in people with multiple myeloma and how this complication can affect your overall outlook.
Hypercalcemia is one of the more common complications of multiple myeloma and can develop for several reasons. A healthcare professional diagnoses this condition by measuring the amount of calcium in your blood or urine.
When your calcium levels rise above the usual range, it’s called hypercalcemia.
Calcium: What does it do, and how much do we need?
Your body is made up of a number of essential minerals, and calcium is one of them. Calcium is stored in your bones and teeth, making them strong and hard. Calcium is also used to help transmit nerve signals, move blood, and manage hormone levels.
Two measurements are used to gauge the amount of calcium in your body: serum calcium and ionized calcium. Serum calcium is a count of how much calcium is in your blood. Ionized calcium, also known as free calcium, measures the total amount of calcium in your body.
Usual ranges for each of these are:
- serum calcium: 8.6 to 10.3 mg/dL
- ionized calcium: 4.4 to 5.2 mg/dL
Calcium intake comes mainly from foods you eat, but some people need to take supplements, too.
Most adults need about 1,000 milligrams (mg) of calcium per day from their diet. If supplements are used, it’s best to only take 500 mg at a time. Taking more than 500 mg at once may lead to the calcium not being fully absorbed by your body.
If you have a condition like multiple myeloma, be sure to discuss any medications or supplements you are taking with a healthcare professional. Things that were OK to take before your diagnosis may not be recommended after it.
There are several reasons why your calcium levels can rise with multiple myeloma. The main reason is believed to be the destruction of bone from the lesions caused by multiple myeloma.
When bones are destroyed, they release extra calcium into your bloodstream and increase your calcium levels. However, a 2020 study found that roughly 91.2 percent of people with multiple myeloma experienced bone destruction while only about 16.8 percent had hypercalcemia. This suggests calcium imbalances can come from other sources, too.
Calcium levels can also rise as other parts of the body are impacted by myeloma. The parathyroid gland plays a big role in calcium regulation, so damage to this gland in any way can cause an imbalance.
There may also be an underlying secondary cause of hypercalcemia in people with multiple myeloma, like an overactive parathyroid gland. Overactivity in this gland may also be an underlying cause of hypercalcemia.
Kidney damage is also a frequent complication of multiple myeloma. Kidneys can play an important role in regulating calcium. The 2020 study mentioned earlier found that kidney damage affected about 81.8 percent of people with multiple myeloma.
Hypercalcemia by itself can be a serious problem, leading to abnormal heart rhythms and even coma. In multiple myeloma, it’s usually a sign of a more serious disease.
People with multiple myeloma who also develop hypercalcemia have an overall lower survival rate than those without this complication. On average, they live roughly 20 months less than multiple myeloma patients without hypercalcemia.
The link between hypercalcemia and more severe multiple myeloma is so strong that it’s used as an indicator of organ damage.
CRAB symptoms in multiple myeloma
According to the Dana-Farber Cancer Institute, organ damage in multiple myeloma is diagnosed based on the presence of CRAB symptoms, which include:
- C = calcium levels (increased)
- R = renal (kidney) dysfunction
- A = anemia
- B = bone lesions
The symptoms of hypercalcemia in multiple myeloma are generally the same as they are in people without this type of cancer. Some people may not even notice any symptoms at all.
Common symptoms of hypercalcemia include:
- appetite loss
- increased thirst
- frequent urination
- muscle weakness
- muscle twitching
- bone pain
In most cases, a healthcare professional will use a blood test to measure your calcium levels. This can be done through a serum calcium test or an ionized calcium test.
The main way to treat hypercalcemia is to correct the underlying condition that first caused it. In people with multiple myeloma and other cancers, this may not be simple.
People who develop hypercalcemia with multiple myeloma are typically treated with IV fluids and bisphosphonates.
Bisphosphonates are commonly used to treat osteoporosis because they can help slow bone loss. This can help reduce the amount of calcium released into your body.
Examples of bisphosphonates include:
- Actonel (risedronate)
- Aredia (pamidronate)
- Boniva (ibandronate
- Fosamax (alendronate)
- Reclast (zoledronic acid)
Hypercalcemia can develop for several reasons in anyone, but it’s most common in people with diseases like multiple myeloma. Hypercalcemia is so common in multiple myeloma that it’s often used as a measure of disease severity.
People who have hypercalcemia with multiple myeloma usually have an overall worse outlook than those without this complication.
If you have symptoms of hypercalcemia, a healthcare professional will run a number of tests to find the cause. If multiple myeloma is the cause, your doctor will treat hypercalcemia as a symptom of your disease.
Always talk with your doctor before beginning any new medications or supplements, especially if you have a chronic condition like multiple myeloma.