Topical treatments for chronic plaque psoriasis: an abridged Cochrane systematic review

Chronic plaque psoriasis is the most common type of psoriasis and is characterized by redness, thickness, and scaling. First-line management is with topical treatments.

We sought to undertake a Cochrane review of topical treatments for chronic plaque psoriasis.

We systematically searched major databases for randomized controlled trials. Trials reported improvement using a range of related measures; standardized, pooled findings were translated onto a 6-point improvement scale.

The review included 177 randomized controlled trials with 34,808 participants, including 26 trials of scalp psoriasis and 6 trials of inverse and/or facial psoriasis. Typical trial duration was 3 to 8 weeks. When compared with placebo (emollient base), the average improvement for vitamin-D analogues and potent corticosteroids was approximately 1 point, dithranol 1.2 points, very potent corticosteroids 1.8 points, and combined vitamin-D analogue plus steroid 1.4 points once daily and 2.2 points twice daily. However, these are indicative benefits drawn from heterogeneous trial findings. Corticosteroids were more effective than vitamin D for treating psoriasis of the scalp. For both body and scalp psoriasis, potent corticosteroids were less likely than vitamin D to cause skin irritation.

Reporting of benefits, adverse effects, and safety assessment methods was often inadequate. In many comparisons, heterogeneity made the size of treatment benefit uncertain.

Corticosteroids are as effective as vitamin-D analogues and cause less skin irritation. However, further research is needed to inform long-term maintenance treatment and provide appropriate safety data.