Smoking Associated With Severity Of Psoriasis

Cigarette smoking is associated with the clinical severity of the skin disease psoriasis, and both smoking and obesity are more prevalent among psoriasis patients, according to two studies in the December issue of Archives of Dermatology, one of the JAMA/Archives journals.

Psoriasis is a chronic, persistent, lifelong disease characterized by scaly red plaques on the surface of the skin. Although psoriasis is not a life-threatening disease, the disability experienced by patients with psoriasis is comparable with that of patients with other chronic illnesses, such as heart disease, diabetes, cancer, and depression, according to background information in the article. Cigarette smoking is a risk factor for many chronic diseases, including psoriasis, but little is known about the effect of smoking on psoriasis severity. Cristina Fortes, Ph.D., of Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy, and colleagues conducted a cross-sectional study to evaluate the association between different components of smoking history and the clinical severity of psoriasis. They analyzed data on 818 adults with psoriasis in inpatient wards of a hospital for skin diseases. “Specifically, patients who smoked more than a pack of cigarettes (more than 20 cigarettes) daily had twice the risk of more severe psoriasis compared with those who smoked ten cigarettes or less per day,” the authors report. Cigarette-years, measured as the product of the intensity and duration of smoking, significantly increased the risk of clinically more severe psoriasis. “Separate analyses for men and women showed that the effect of cigarette-years on psoriasis severity was stronger for women than for men,” the authors write. “Smoking is associated with the clinical severity of psoriasis and highlights the importance of smoking cessation in patients with psoriasis,” they conclude. “The prevalence of obesity in patients within the UPI population was higher than that in the general Utah population (34 percent vs. 18 percent) and higher than that in the non-psoriatic population attending our clinics,” the authors write. “The prevalence of smoking in the UPI population was higher than in the general Utah population (37 percent vs. 13 percent) and higher than in the non-psoriatic population.” The authors found that obesity appears to be the consequence of psoriasis, and not a risk factor for onset of the disease. “Smoking appears to have a role in the onset of psoriasis, but obesity does not,” they write. “It seems certain that the cost of providing care for psoriasis – when coupled with the increased frequency of obesity and smoking in patients attending clinics such as ours – will continue to increase,” the authors conclude. “An effort to control obesity and smoking in psoriasis patients and an increased appreciation of the effects of these comorbidities are clearly needed.” (Source: Arch Dermatol. 2005;141:1589-1590: JAMA/Archives journals: January 2006.)