Individual differences in chemotherapy-induced anticipatory nausea

Genetic and environmental influences on one-trial conditioned context aversion in mice

Anticipatory nausea (AN) is caused by an association between contextual cues and the experience of nausea (the side effects of chemotherapy or radiation treatment) and it develops predominantly in female patients undergoing chemotherapy. Preclinical studies in rodents show that the administration of an illness-inducing agent in the presence of novel contextual cues can cause conditioned context aversion (CCA) and this has been proposed to model AN. The literature also suggests that brief pre-exposure to a novel context prior to shock delivery is critical in the development of contextual fear conditioning in rodents (a phenomenon known as Immediate Shock Deficit), but this has not been assessed in CCA. The aim of present study was to develop a CCA paradigm to assess this in outbred (CD1) and inbred (C57BL/6J) mice and evaluate potential sex differences. The results revealed that a single conditioning trial in which a distinctive context was paired with LiCl-induced illness was sufficient to elicit a conditioned response in both female and male CD1 outbred mice, but not in C57BL/6J inbred mice. In addition, CCA was facilitated when animals had prior experience with the context. Finally, outbred female mice showed longer and more robust retention of CCA than male mice, which parallels clinical findings. The results indicate the importance of using CD1 outbred mice as an animal model of AN as well as examining sex differences in the CCA paradigm. Similar findings in humans encourage the future use of this novel CCA preclinical mouse model.

Maintenance of conditioned place avoidance induced by gastric malaise requires NMDA activity within the ventral hippocampus

It has been reported that during chemotherapy treatment, some patients can experience nausea before pharmacological administration, suggesting that contextual stimuli are associated with the nauseating effects. There are attempts to reproduce with animal models the conditions under which this phenomenon is observed to provide a useful paradigm for studying contextual aversion learning and the brain structures involved. This manuscript assessed the hippocampus involvement in acquiring and maintaining long-term conditioned place avoidance (CPA) induced by a gastric malaise-inducing agent, LiCl. Our results demonstrate that a reliable induction of CPA is possible after one acquisition trial. However, CPA establishment requires a 20-min confinement in the compartment associated with LiCl administration. Interestingly, both hippocampal regions seem to be necessary for CPA establishment; nonetheless, inactivation of the ventral hippocampus results in a reversion of avoidance and turns it into preference. Moreover, we demonstrate that activation of dorsal/ventral hippocampal NMDA receptors after CS–US association is required for long-term CPA memory maintenance.

Chemotherapy-Induced Nausea and Vomiting in Women With Gynecological Cancer: A Preliminary Single-Center Study Investigating Medical and Psychosocial Risk Factors

BACKGROUND

Chemotherapy is the treatment of choice for many gynecological tumors, but cytotoxic drugs lead to a wide range of stressful side effects; nausea and vomiting are 2 of the most common and distressing consequences of many chemotherapy regimens.

OBJECTIVE

The aim of this study is to investigate various risk factors that could influence the experience of nausea and vomiting after the first chemotherapeutic infusion.

METHODS

Women treated for various gynecological cancers (n = 94) took part in the study. Pharmacological and personal risk factors in the development of chemotherapy-induced nausea and vomiting (CINV) were assessed with the use of the State-Trait Anxiety Inventory and a self-report questionnaire. Regression analyses (both univariate and multiple) were performed to establish risk factors associated with CINV.

RESULTS

The study highlights the importance of working status (being involved in a working activity during treatment) as a protective factor for developing chemotherapy-induced nausea. Furthermore, younger age, levels of state anxiety, chemotherapy-induced nausea in previous treatments, and alcohol intake were found to have an effect on CINV, increasing its risk. Emetogenic potential was associated only with the presence of delayed vomiting.

CONCLUSIONS

Although this is a preliminary study into the risk factors of CINV in gynecological tumors, these findings offer support that personal risk factors contribute to individual differences in the frequency and severity of CINV.

IMPLICATIONS FOR PRACTICE

Personal factors should be taken into consideration by the multidisciplinary treating team in gynecology.

Countermeasures against methotrexate intolerance in juvenile idiopathic arthritis instituted by parents show no effect

Objectives

A high proportion of children with JIA will develop intolerance to MTX with anticipatory and associative gastrointestinal adverse effects. Parents and physicians frequently try to alleviate these symptoms with a variety of countermeasures. The objective of this study was to investigate the course of MTX intolerance within a 6 month period, and the effects of countermeasures on MTX intolerance severity.

Methods

We performed a prospective study of 196 consecutive JIA patients treated with MTX. Intolerance was determined using the Methotrexate Intolerance Severity Score (MISS) questionnaire. MISS and countermeasures instituted by parents or physicians were determined at four time points, each 2 months apart. Countermeasures, classified into four types (antiemetic drugs, covert dosing, taste masking and complementary medicine), were analysed using non-parametric statistics and mixed linear modelling, adjusted by propensity scoring for use of countermeasures.

Results

Ninety patients (46%) showed MTX intolerance, with 58 (64%) using countermeasures at time of inclusion. Median MISS at inclusion was 11 (interquartile range = 8.0-14.25), and did not change significantly over time. No significant difference in MISS score was observed between patients receiving countermeasures and those who did not. For specific countermeasures, MISS did not change significantly after introduction. Sensitivity analysis adjusting for propensity score indicated no significant association of MISS severity on parents' decision to implement any countermeasures.

Conclusion

MTX intolerance was present in many children with JIA and symptoms decreased little in the short term. Various modalities used as countermeasures against nausea by parents showed no discernible effect.