Nocebo effects, i.e. reduced treatment effects due to patients’ negative expectations, play a role in itch. Recent studies have shown that nocebo effects can be induced experimentally on itch and... Show moreNocebo effects, i.e. reduced treatment effects due to patients’ negative expectations, play a role in itch. Recent studies have shown that nocebo effects can be induced experimentally on itch and also be minimized and even turned into the opposite direction, i.e. placebo effects. It is not known whether these effects generalize to itch-associated scratching behaviour. The aim of this study was to determine whether induction and reversal of nocebo effects on itch evoked by electrical and histamine stimuli generalized to scratching. Ninety-seven healthy participants were included in the study. The manipulation was successful, as during the nocebo learning phase, increased scratching responses were found for higher intensity compared with lower intensity itch stimuli. During the testing phase of induction or reversal of the nocebo effects, however, no significant nocebo effects or reversed nocebo effects, were found in scratching. Thus, no straightforward generalization of nocebo effects from itch to scratching was found in this laboratory setting. Further investigation into possible generalization is needed in different settings and in patients with chronic itch. Show less
Roest, Y.B.M.; Middendorp, H. van; Evers, A.W.M.; Kerkhof, P.C.M. van de; Pasch, M.C. 2018
Alopecia areata (AA) is an immune-mediated disease causing temporary or permanent hair loss. Up to 46% of patients with AA also have nail involvement. The aim of this study was to determine the... Show moreAlopecia areata (AA) is an immune-mediated disease causing temporary or permanent hair loss. Up to 46% of patients with AA also have nail involvement. The aim of this study was to determine the presence, types, and clinical implications of nail changes in patients with AA. This questionnaire-based survey evaluated 256 patients with AA. General demographic variables, specific nail changes, nail-related quality of life (QoL), and treatment history and need were evaluated. Prevalence of nail involvement in AA was 64.1%. The specific nail signs reported most frequently were pitting (29.7%, p = 0.008) and trachyonychia (18.0%). Red spots on the lunula were less frequent (5.1%), but very specific for severe AA. Nail-related QoL was only minimally affected by nail changes. In conclusion, nail involvement is common in patients with AA and presents mostly with pitting and trachyonychia. The presence of these nail changes reflects the severity of the disease, with red spots on the lunula as a predictor for severe alopecia Show less
