Smoking Increases Risk of Disease Progression in MS Patients

Each additional year of smoking after multiple sclerosis diagnosis accelerated the time to secondary progressive disease conversion.

For patients with multiple sclerosis (MS), the biggest fear is disease progression. But the time until progression can be prolonged if current smokers who are diagnosed with MS discontinue smoking upon diagnosis, a recent study suggests.

The study, published online by JAMA Neurology, found that continued smoking after a diagnosis of MS appears to be associated with accelerated disease progression compared with patients who quit smoking. Smoking is a known risk factor of MS.

While MS begins as a course of irregular and worsening relapses, it usually changes after about 20 years to something called secondary progressive (SP) disease. The time from onset to conversion to SPMS is a frequently used measure of disease progression.

The study evaluated a cohort of 728 patients in Sweden with MS who smoked at diagnosis. Of the 728, 216 converted to SP. Among the 728 smokers, 332 were classified as “continuers” who smoked through the year after diagnosis and beyond, and 118 were “quitters” who stopped smoking the year after diagnosis.

Information concerning the disease progression of 1012 patients who never smoked was also included. Nearly 60% of patients with MS were smokers in the present study cohort and in a Swedish cohort of new cases, according to the study background.

The researchers found that each additional year of smoking after diagnosis accelerated the time to SP conversion by 4.7%. The study also suggests that those who continued to smoke each year after diagnosis converted to SP fasted (at age 48) than those who quit (at age 56).

“This study demonstrates that smoking after MS diagnosis has a negative impact on the progression of the disease, whereas reduced smoking may improve patient quality of life, with more years before the development of SP disease. Accordingly, evidence clearly supports advising patients with MS who smoke to quit. Health care services for patients with MS should be organized to support such a lifestyle change,” the study concluded.