Cigarette Smoking, Body Mass Index, and Stressful Life Events as Risk Factors for Psoriasis: Results from an Italian Case–Control Study

Abstract

We conducted a case-control study to analyse the association of psoriasis of recent onset with smoking habits, body mass index (BMI) and stressful life events. Cases (n=560; median age 38) were patients with a first diagnosis of psoriasis and a history of skin manifestations of no longer than two years after the reported disease onset. Patients with a new diagnosis of skin diseases other than psoriasis (n=690; median age 36) were selected as controls. The risk of psoriasis was higher in ex- and current smokers than in never-smokers, the relative risk estimates (OR) being 1.9 for ex-smokers and 1.7 for smokers. Smoking was strongly associated with pustular lesions (32 patients, OR=5.3 for smokers). The frequency of psoriasis varied significantly in relation to a family history of psoriasis in first degree relatives, BMI (OR=1.6 and 1.9 for over weighted, BMI 26-29, and obese, BMI >/= 30, respectively) and stressful life event score (compared to the lower index quartile, the OR being 2.2 for index values >/=115). Risk estimates, when taking into consideration the combined effect of these factors with smoking habits, were consistent with a multiplicative model of risk combination with no significant statistical interaction.

National Psoriasis Foundation clinical consensus on psoriasis comorbidities and recommendations for screening

“…36 Smoking has also been strongly associated with pustular psoriasis. 33 The increased prevalence of smoking seen in patients with psoriasis could contribute to an elevation in cardiovascular risk in patients with psoriasis.…”

“…39,40 Psoriasis was first associated with obesity in several large, epidemiologic studies from Europe. 33,41,42 Recently, a database from the UK has shown the BMI to be elevated in psoriasis patients. In severe psoriasis the BMI is higher than in mild psoriasis.…”

“…9 BMI has also been shown to be a risk factor for psoriasis in an Italian study. 33 In the Nurses Health Study II, increased adipocity and weight gain were shown to be strong risk factors for the development of psoriasis in women. 44 An association between psoriasis and elevated BMI may be yet another factor which predisposes individuals with psoriasis to cardiovascular disease.…”

Psoriasis ve Obezite

“…Naldi ve ark. 'nın 560 psoriatik hastayı dahil ettikleri vakakontrol çalışmasında ise BMI 26-29 arasında olanlarda 1,6 kat, BMI 30'un üzerinde olanlarda 1,9 kat daha fazla psoriasis olduğu gösterilmiştir 27 . 16,851 psoriasisli hastanın katıldığı başka bir çalışmada ise özellikle 35 yaşından genç hastalarda 65 yaşından yaşlı olanlara göre obezite riskinin arttığı gösterilmiştir 9 .…”

Impact of obesity on disease severity in patients with plaque type psoriasis

“…Tümör nekroz faktör (TNF)-alpha (α), interlökin (IL)-6 ve IL-8 gibi psoriasis patogenezinde de önemli olan proinflamatuvar sitokinlerin, adipoz dokudan salınımı obezitede artmıştır 13 . Son yıllarda yapılan çalışmalarda, obezitenin, psoriasis prevalansını arttırdığı veya psoriasisin başlangıcını tetiklediği öne sürülmektedir 11,14,15 . Ayrıca obezite ile psoriasisin klinik şiddeti arasındaki ilişkiyi araştıran çalışmalar da mevcuttur [16][17][18] .…”