The severity of the psoriasis affects the outcome
As Kamstrup pointed out, the severity of the psoriasis had a significant impact on the adjusted hazard ratios. Those who were receiving a systemic treatment considered consistent with extensive disease were classified as severe, while those who were not receiving such therapies were classified as mild for the purposes of the study. The adjusted hazard ratios were proven to be significant for mild psoriasis and Hodgkin lymphoma in the study (2.08, 95% CI 1.38-3.15). Severe psoriasis was also found to be significant for non-Hodgkin lymphoma (1.64, 95% CI 1.12-2.40 and cutaneous T-cell lymphoma (13.63, 95% CI 6.72-27.64).