Preventing adverse information effects on health outcomes: A self-affirmation intervention reduced information-induced cognitive decline in gastrointestinal cancer patients

Rationale: Nocebo studies show that informing patients about treatment side effects can adversely impact expectancies and symptom reporting.

Objective: The current study examined how to inform patients fully about treatment side effects without increasing their occurrence. Extending theoretical assumptions about self-affirmation from the social-psychological to the medical domain, we tested whether allowing cancer patients to self-affirm prior to informing them about potential cognitive decline reduced the occurrence of Adverse Information Effects (AIE) on cognitive problem reporting (CPR) and verbal memory performance.

Method: Participants were 90 Dutch and Belgian gastrointestinal cancer patients with and without chemotherapy experience. Patients were randomized across three experimental conditions (information about chemotherapy-related cognitive problems with or without self-affirmation; no-information control) before completing an online questionnaire. Data were collected from May until August 2015. Main dependent variables were CPR and verbal memory performance. Stigma consciousness was included as a moderator.

Results: Informing patients about chemotherapy-related cognitive problems increased CPR and decreased scores on two out of three memory measures. Self-affirmation reduced these AIE. Stigma conscious patients reported more problems in the information than the self-affirmation group.

Conclusions: Nocebo effects may be reduced by allowing patients the opportunity to restore their self-integrity at the implicit level. Self-affirmation has the potential to reduce AIE in patient populations without withholding relevant information about potential treatment side effects.