SAN FRANCISCO – Nnenna Ezeh reported at an international congress on systemic lupus erythematosus.
Bruce Jancin/MDedge News
Nnenna Ezeh
“We saw in our study a suggestion of a dose-response relationship. If we tell patients, ‘The more you smoke, the more likely you are to have chronic skin disease or skin damage that’s permanent,’ it could be a way to trigger more smoking cessation strategies in their mind,” said Ms. Ezeh, of the University of Wisconsin, Madison. “We know that skin manifestations of lupus have a major negative impact on a patient’s quality of life, so this could be a way to decrease smoking by saying, ‘Not only does smoking impact your heart and put you at risk for cardiovascular disease, it also affects your skin.’ It’s a way to bridge the priorities that physicians have with the priorities that patients have.”
She presented a retrospective study of the medical records of 632 consecutive SLE patients seen at the university medical center’s ambulatory rheumatology clinic. Slightly more than 60% of them were never smokers; 8.7% had a history of low smoking exposure, defined as less than 5 pack-years; 5.8% had a medium-smoking history of 5-10 pack-years; 15% had a high-smoking history, with more than 10 pack-years; and the smoking history of 10% of the patients was unrecorded.
In a multivariate analysis adjusted for age, sex, and race, the low-smoking group was ninefold more likely than never smokers to develop any mucocutaneous manifestations of SLE, including a malar or discoid rash, mucosal ulcers, photosensitivity, alopecia, or scarring. They were also 3.7 times more likely to meet any Systemic Lupus International Collaborating Clinics (SLICC) cutaneous criteria and twofold more likely than never smokers to meet any of the American College of Rheumatology cutaneous criteria. Patients with an intermediate smoking exposure history of 5-10 pack-years were 2.3-fold more likely to meet any SLICC cutaneous criteria.
The risks of meeting SLICC chronic cutaneous criteria and SLICC Damage Index skin damage criteria rose in a linear fashion with the number of pack-years of smoking. Those SLE patients with more than a 10 pack-year smoking history were 4.2-fold more likely than never smokers to fulfill any SLICC Damage Index skin damage criteria, which consist of scarring alopecia, extensive scarring, or skin ulcers. The heaviest smokers were also at 2.1-fold increased risk of discoid lupus and 2.2-fold more likely to meet SLICC chronic cutaneous criteria, according to Ms. Ezeh.
Patients of color, who comprised 18% of the study population, were significantly more likely to smoke than white patients. Independent of their smoking history, however, they had significantly increased risks of chronic cutaneous manifestations of lupus and of irreversible skin damage.
Ms. Ezeh reported having no financial conflicts regarding her study, supported by a grant from the Rheumatology Research Foundation.