The effect of overweight and obesity on psoriasis patients in Chinese Han population: a hospital-based study

Background Accumulating evidence indicates that psoriasis is associated with increased risk of overweight and obesity. However, few studies have investigated this relationship in Chinese Han population. Objective The aim of this study was to explore the relationship between overweight/obesity and psoriasis and to evaluate the overweight/obesity effect on the clinical features of psoriasis in Chinese Han population. Methods A hospital-based study was conducted, which involved in 4452 patients and 1166 controls of Chinese Han through epidemiological investigation. Controls used in the study were individuals without psoriasis from health examination centre, and other skin disease patients from outpatient department. Results Compared with the control group, a significantly greater prevalence of overweight and obesity was observed in psoriasis patients. The estimated ORs were 1.301 (95% CI, 1.105-1.531) and 1.680 (95% CI, 1.134-2.491) respectively. The disease severity of psoriasis measured by psoriasis area and severity index (PASI) was statistically correlated with body mass index (BMI) (r = 0.184, P < 0.01). Moreover, a high proportion of overweight patients had affected hands or/and feet, buttocks, trunk, legs, arms and arthritis (P < 0.01). Conclusions Our study suggested that psoriatic patients have a higher prevalence of overweight and obesity compared with non-psoriatic patients in Chinese Han population. Overweight and obesity has different risk effect on severity and manifestations of psoriasis and might be useful for better evaluating psoriasis clinically.