In a project funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA), researchers discovered that there is no evidence of a difference in clearance rates between patient self-treatment for verrucae (A type of wart) and treatment received by healthcare professionals.

Verrucae are common, infectious and sometimes painful, and although most verrucae spontaneously disappear without treatment, many patients seek out health professionals to remove the wart because they experience pain or it prevents them from sporting activities.

According to estimates nearly two million people annually visit their GP regarding the treatment of warts, representing an annual cost of more than £40 million.

Sarah Cockayne of the University of York conducted a study for the treatment of verrucae, in which she compared the clinical and cost-effectiveness of cryotherapy using liquid nitrogen given by a healthcare professional and compared it with self-treatment in patients using salicylic acid. Cryotherapy is a freezing method considered to be a more painful treatment.

Mrs. Cockayne, who led the research, stated:

“There are many different methods of treating verruca but very little good quality research has been done to determine what is the best form of treatment. There is some evidence to suggest that salicylic acid is effective and safe but there is no clear evidence that cryotherapy is more effective than treatment with salicylic acid.”

Cockayne recruited a total of 240 participants with verrucae from fourteen sites in England, Scotland and Ireland, who were divided into two groups; 117 patients received cryotherapy administered by a healthcare professional and 123 patients applied salicylic acid by self-treatment.

The cryotherapy group received an initial, 10 second-long gentle freeze with subsequent treatments according to the site’s usual practice, including debridement, masking and padding of the site. Patients in the self-treatment group were instructed to apply salicylic acid once daily for a maximum of eight weeks.

At 12 weeks and at six months after enrollment, study results proved that there is no differential evidence in verrucae patients’ clearance rates between both groups, although cryotherapy is linked to higher mean costs per additional healed patient compared with salicylic acid.

The study results remained unchanged when the analysis was repeated but controlled for age, e.g. whether or not previous treatment had occurred and type of verrucae or patients’ preferences. Researchers point out, that the results only apply to verrucae or plantar warts and not to warts at other sites, such as the hands, which may respond differently to cryotherapy.

Mrs. Cockayne concluded:

“We were motivated to conduct this trial when the Cochrane systematic review into the treatment of cutaneous warts highlighted the lack of good quality evidence to support the use of cryotherapy over simple topical treatments. Healthcare professionals will need to write patient information sheets in such a way to give patients realistic expectations in relation to the effectiveness of cryotherapy treatment.”

Written by Petra Rattue