Parathyroid hormone raises blood calcium level

Dear Dr. Roach: Iaman 88-year-old man in quite good health. I have had high blood calcium for many years, usually around 10.7. I take pravastatin and triamterene/ HCTZ. My doctor has been a little concerned and has been monitoring it. She sent me to an endocrinologist. Neither suggested treating it.

I recently saw a Veteran’s Affairs doctor who is more concerned. My most recent calcium level is 11, and she took me off the triamterene/ HCTZ. She also had me do a 24-hour calcium, with a result of 266 mg/24 hours.

I have read that high blood calcium is more dangerous than high cholesterol. I’m not in favor of surgery unless absolutely necessary. — W.

Dear W.: It is very likely that you have a condition called primary hyperparathyroidism. This is caused by an excess of parathyroid hormone. I suspect one of your doctors has already confirmed this with a blood test.

There are several indications for surgery. One is a very high blood calcium, greater than a single point over normal. The magnitude of the harm is relatively small and the benefit of surgery is not seen until 15 years after.

One way that PTH keeps blood calcium levels high is by drawing calcium out of the bones, so you should have an evaluation of your bone density.

Another reason to consider surgery would be a history of kidney stones or progressive worsening of kidney function.

I suspect your doctor and her specialist are likely to evaluate you thoroughly and will recommend surgery if they think surgery is superior to medical treatment. I suspect you will not require surgery.