Background: Psoriasis may significantly reduce quality of life. Previous studies reported an association of psoriasis and cardiovascular risk factors and cardiovascular events. The extent to which psoriasis is associated with psychiatric morbidity and the role of psychiatric comorbidity as a potential confounder of the association between psoriasis and cardiovascular morbidity require further investigation.
Objectives: To study the association between psoriasis, psychiatric morbidity and cardiovascular morbidity.
Methods: Case-control study utilizing an interdisciplinary administrative outpatient database from Germany. Patients with confirmed diagnosis of prevalent psoriasis within the study period (2003-2004) (n = 3147, mean age 57 years) were individually matched for age and gender with 3147 controls without psoriasis. The relationship of psoriasis with psychiatric morbidities (depression, stress-related disorders, behaviour disorders and schizophrenic disorders), cardiovascular risk factors (diabetes, hypertension, obesity and dyslipidaemia) and cardiovascular events [myocardial infarction (MI), stroke] was investigated using logistic and linear regression models.
Results: Crude analyses suggested an association of psoriasis with depression, stress-related disorders, behaviour disorders and cardiovascular risk factors, but not with MI [odds ratio (OR) 1.14; 95% confidence interval (95% CI) 0.81-1.62] or stroke (OR 0.97; 95% CI 0.61-1.54). Multivariate models controlling for age, gender and consulting behaviour indicated that psoriasis is independently associated with depression (OR 1.49; 95% CI 1.20-1.86), stress-related disorders (OR 1.41; 95% CI 1.22-1.62), behaviour disorders (OR 1.58; 95% CI 1.05-2.39), diabetes (OR 1.21 95% CI 1.04-1.40), hypertension (OR 1.34; 95% CI 1.18-1.51), dyslipidaemia (OR 1.29; 95% CI 1.07-1.55), and obesity (OR 1.63; 95% CI 1.39-1.90). For each psychiatric condition, the likelihood of being affected significantly increased with each physician visit due to psoriasis, suggesting that the risk of psychiatric comorbidity increases with the severity of psoriasis.
Conclusion: Psoriasis appears to be independently associated with major psychiatric disorders and with cardiovascular risk factors, but not with cardiovascular events.