Patients respond best to only most relevant patch test results

January 1, 2011

Experts in contact dermatitis are finding that good outcomes after patch testing might be more of a matter of how the results are used than anything else. According to Matthew J. Zirwas, M.D., director, Contact Dermatitis Center, Ohio State University Medical Center, Columbus, Ohio, some new studies are revealing novel approaches for managing patients after patch testing that are more likely to benefit the patients.

Key Points

"It's a matter of applying the psychology of learning to medicine," Dr. Zirwas says. "The more information we give patients, the more likely they are to feel overwhelmed and not take appropriate action based on that information."

Results from a Mayo Clinic study - results that were not the main take-away of the article, but rather were an unanticipated offshoot of the trial - showed that patients who were told they were allergic to three or more allergens were much less likely to remember the names of those substances six months later than those who were told about only one substance.

Keep it relevant

Dr. Zirwas suggests avoiding discussing results that are positive but not relevant to the patient in terms of treatment, unless the patient insists on knowing about all allergens.

"If the patient had negative reactions to A, B, C and D and only A and C are important, it's likely that the patient will remember information about two important allergens, but less likely if you discuss all four with them," he says.

"The main thing that is going to change is that we should really focus on minimizing the amount of information that we give patients about positive test reactions that are not relevant, and make sure the information we do give them is accurate and essential to improving their situation," Dr. Zirwas says.

Determining relevance can be tricky at times, however. A recent study looked at this issue to find out whether physicians accurately assigned relevance to the allergens, with relevance being defined as the patients getting better when they avoided the allergens.

"It turned out that the relevance of some allergens was overestimated and the relevance of others was underestimated," Dr. Zirwas says.

Two examples were fragrance, overestimated because patients didn't get better by staying away from the allergen, and gold, underestimated because patients did get better if they avoided it.