Analysis of Risk Factors for Psoriasis Recurrence Using Proportional Rates Model

Psoriasis is a chronic, recurrent, genetic skin disease without any definite cure. Unfortunately, studies on psoriasis are limited in our country and few studies have been done regarding its risk factors and time of occurrence. The current study aimed to assess risk factors of psoriasis recurrence through proportional rates model. The current study was conducted at the Department of Dermatology, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran, from March 2006 through April 2014. A total of 160 patients with confirmed diagnosis of psoriasis were recruited and risk factors for the recurrence of psoriasis were identified and evaluated by applying the proportional rates model. The results of this study indicated that infection, stress, family history, blood calcium level, smoking, and number of white blood cells were risk factors for recurrence of psoriasis. Moreover, 56.3% of patients did not have any leading-to-hospitalization relapse after enrolling in the study with one relapse episode reported in 23%, two in 10.6%, three in 4.4%, and four or more relapse episodes in 5.6% of participants. It is essential to identify people with psoriasis. Another important point is to inform patients of the causes of this disease to decrease the risk of recurrence. In addition, it is recommended to educate patients about reduction or cessation of smoking as a part of psoriasis treatment.