Women with lupus have twice the risk of developing cervical cellular changes that could progress to cancer, a new study shows.

About 1.5 million people in the U.S. have lupus, which is a chronic inflammatory disease that can affect any organ and system, but mainly involves the joints, kidneys and skin. Lupus predominately affects women, occurring 10 times more often than in men, and often starting when they are in their 20s and 30s.

This new Swedish study found a doubled risk of pre-malignant cervical changes, which is known as cervical dysplasia, occurred among women with lupus compared to the general female population.  Such changes potentially raise the risk of cervical cancer, the researchers say.

The rate was higher among those women treated with a systemic immunosuppressive drug, compared to those treated with only an antimalarial without additional immunosuppressive treatment. Antimalarial drugs are an accepted part of lupus treatment.

Previous studies noted that the rate of cervical cancer was higher in women with lupus, but it was not known whether this stemmed from the disease or the treatment, the researchers noted.

As cervical dysplasia increases the risk of cervical cancer, the study highlights the need for regular cervical screening in all women with lupus, regardless of whether the increased risk is due to disease severity or treatment, the investigators say.

The study was presented at the European League Against Rheumatism Annual Congress.