Science and Health

Low levels of vitamin D may worsen leukemia

(Xinhua)
Updated: 2010-11-14 13:50

LOS ANGELES - Low levels of vitamin D may lead to deterioration in certain Leukemia patients, whereas adequate levels were linked to longer survival, US researchers have found.

The findings result from a study of 390 chronic lymphocytic leukemia (CLL) patients, 30 percent of whom had insufficient vitamin D levels (less than 25 nanograms per milliliter) at the time of cancer diagnosis.

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After a median follow-up of three years, patients with insufficient vitamin D levels were 66 percent more likely to have disease progression and to require chemotherapy. They also had a twofold increased risk of death, compared to those with adequate vitamin D levels.

The study also found that increasing vitamin D levels in patients was linked to longer survival times, even after controlling for other factors associated with leukemia progression.

Similar findings were seen in a different group of CLL patients who were followed for 10 years, according to the researchers at the Mayo Clinic in Rochester, Minnesota and the University of Iowa.

"This tells us that vitamin D insufficiency may be the first potentially modifiable risk factor associated with prognosis in newly diagnosed CLL," said study author and hematologist Dr Tait Shanafelt of the Mayo Clinic.

This is an important finding for both patients and doctors, the researchers said.

CLL, a cancer of the white blood cells (lymphocytes), mainly affects adults. Although CLL is often diagnosed at an early stage, the standard approach is to wait until patients develop symptoms before beginning chemotherapy, explained Shanafelt.

"This watch-and-wait approach is difficult for patients because they feel there is nothing they can do to help themselves," Shanafelt said in news release published by HealthDay News on Friday.

"It appears vitamin D levels may be a modifiable risk factor for leukemia progression. It is simple for patients to have their vitamin D levels checked by their physicians with a blood test. And if they are deficient, vitamin D supplements are widely available and have minimal side effects."

The researchers are planning another study to see if reversing low vitamin D levels in patients will improve their prognosis.