Study Further Establishes Smoking-Psoriasis Connection

It’s generally well-understood that smoking cigarettes exacerbates symptoms of psoriasis. But a study in the Polish population, published in PostÄ™py, clarifies and strengthens the link between smoking and the development of psoriatic lesions.

“The presence of the same genetic predisposition is not sufficient for the development of psoriasis,” the study authors note. “Provocative factors that initiate a cascade of immune disorders play an important role in the formation of lesions.” Smoking is key among them.

Smoking releases large amounts of free radicals that stimulate cell signaling pathways active in psoriasis, regardless of cytokines, including mitogen-activated protein kinase (MAPK), nuclear factor-B (NF-B), Janus kinase and JAK-STAT pathways. Nicotine present in cigarettes also stimulates dendritic cells, macrophages and keratinocytes, releasing cytokines including tumor necrosis factor (TNF), Interleukin-6, and others. Smoking can also increase the expression of certain genes that can lead to psoriasis.

The current study included 62 patients with psoriasis aged 30 to 49 years, including 29 smokers (9 women and 20 men) treated at the out-patient clinic and the Department of Dermatology, Municipal Hospital in Olsztyn, Poland. The control group consisted of 861 people from a large Polish population study (NATPOL) conducted in 2011. Smoking frequency, body mass index (BMI), waist circumference, and blood pressure were also examined. Dermatological examination assessed the severity of psoriasis.

Assessment of smoking in the study group was compared to the NATPOL 2011 control group. Patients with psoriasis are more likely to smoke cigarettes compared to the NATPOL 2011 control group. These differences were also found considering patients’ gender: the frequency of smoking is 25% higher in males with psoriasis. No correlations were found in the groups with metabolic syndrome and psoriasis.

”Nicotine addiction may initiate psoriasis in genetically predisposed individuals and influences the disease severity,” the study authors observed. “[Earlier research had shown that] the risk increases with the number of cigarettes smoked daily and is higher in women than men: it is about 2.5 to 3.3 times higher among women who smoke more than 20 cigarettes per day and about 1.7 times higher among smoking men. Our own research showed a higher percentage of people addicted to smoking among patients with psoriasis, especially in males.”

The authors also noted an interesting correlation between smokers and those who abuse alcohol in the psoriasis population. “It should be noted that psoriasis can have an impact on self-esteem and suffering from the disease can cause stress and the patients are more likely to turn to alcohol and cigarettes.”