Epidemiological determinants of psoriasis

A cross-sectional study was conducted on 102 cases having clinical manifestation of psoriasis with a view to evaluate the epidemiological determinants of psoriasis. Psoriasis constituted 1.49% of the total dermatological disorder. Seventy patients (68.6%) were males and thirty two (31.4%) were females with a male to female ratio of 2.18:1. The mean age was 30.76±13.17 years in male and 26.94±14.94 years in female. Sixteen (15.7%) patients had one or more family member having psoriasis with male and female in equal frequency. Regarding precipitating factors, psoriasis was developed after trauma in 4.9%, infection 3.9%, stressful life events 6.9% and drugs 2.9%; and was exacerbated after trauma in 5.9%, infection 5.9%, stressful life events 35.3% and drugs 12.7%. The disease showed improvement in summer (27.5%) and found deteriorated in winter (47.1%). Sunlight had beneficial effect in 33.3% of cases. During pregnancy improvement was observed in 50% but flare up in 22.2% of cases. Fifty percent of patients were smokers, 41.2% were non-smokers and 13.7% were ex-smokers. Forty percent had Body Mass Index (BMI) between 22 to 26 Kg/m², 40.2% had less than 22 Kg/m² and 15.7% had above 26 Kg/m². It was concluded that the prevalence of psoriasis among dermatological patients was similar to results reported in Turkey and in Northern India. The precipitating factors, such as smoking, stressful life events, infection, trauma, sunlight, pregnancy, drugs, and seasonal variations could influence the development of psoriasis and affect its clinical expression.