A review of the literature on symptom clusters in studies that included oncology patients receiving primary or adjuvant chemotherapy.

AIMS AND OBJECTIVES: To summarise the current state of knowledge of symptom clusters research from studies that included, as part of their sample, patients who were receiving primary or adjuvant chemotherapy. BACKGROUND: Since the concept of a symptom cluster was first introduced into the oncology literature in 2001, only four comprehensive reviews of symptom clusters research in oncology patients were identified that provide insights into this important concept in symptom management research. DESIGN: A comprehensive review of the literature. METHODS: A comprehensive literature search was conducted for the years 2000 to 2016. Only 19 studies met the inclusion criteria for this literature review. These studies were evaluated in terms of the symptom assessment instruments used; the statistical analysis methods used; the symptom dimension(s) used to create the symptom cluster(s); the number and types of symptom clusters identified; and whether the specific symptom clusters changed over time. RESULTS: The number of symptom clusters identified ranged from one-seven. The majority of the studies used some type of factor analysis to create the symptom clusters. The most common symptom dimension used to create the clusters was symptom severity. A "gastrointestinal symptom cluster" was the most common symptom cluster identified. Across the eight longitudinal studies, for half of these studies the symptom clusters remained relatively stable over time. CONCLUSIONS: Additional research is needed in oncology patients to address the assessment of symptom clusters, the specific nature of symptom clusters and whether symptom clusters change over time.

Stability of Symptom Clusters in Patients With Breast Cancer Receiving Chemotherapy.

CONTEXT: Patients with breast cancer who undergo chemotherapy (CTX) experience between 10 and 32 concurrent symptoms. An evaluation of how these symptoms cluster together and how these symptom clusters change over time may provide insights into how to treat these multiple co-occurring symptoms. OBJECTIVES: The purposes of this study were to determine the occurrence rates and severity ratings for 38 common symptoms, evaluate for differences in the number and types of symptom clusters, and evaluate for changes over time in these symptom clusters (i.e., before CTX, the week after CTX, and two weeks after CTX). METHODS: At each of the assessments, a modified version of the Memorial Symptom Assessment Scale was used to assess the occurrence and severity of the 38 symptoms. Exploratory factor analyses were used to extract the symptom clusters. RESULTS: Although across the two symptom dimensions (i.e., occurrence and severity) and the three assessments, eight distinct symptom clusters were identified, only five were relatively stable across both dimensions and across time (i.e., psychological, hormonal, nutritional, gastrointestinal, and epithelial). Two of the additional clusters varied by time but not by symptom dimension (i.e., sickness behavior and weight change). The CTX neuropathy cluster was identified only at the assessment performed in the week after CTX. CONCLUSION: These findings provide insights into the most common symptom clusters in patients undergoing CTX for breast cancer. In addition, the most common symptoms within each cluster appear to be relatively stable across the two dimensions, as well as across time.

Differences in symptom clusters identified using symptom occurrence rates versus severity ratings in patients with breast cancer undergoing chemotherapy.

PURPOSE: One of the unanswered questions in symptom clusters research is whether the number and types of symptom clusters vary based on the dimension of the symptom experience used to create the clusters. Given that patients with breast cancer receiving chemotherapy (CTX), report between 10 and 32 concurrent symptoms and studies of symptom clusters in these patients are limited, the purpose of this study, in breast cancer patients undergoing CTX (n = 515), was to identify whether the number and types of symptom clusters differed based on whether symptom occurrence rates or symptom severity ratings were used to create the clusters. METHODS: A modified version of the Memorial Symptom Assessment Scale was used to assess for the occurrence and severity of 38 symptoms, one week after the administration of CTX. Exploratory factor analysis was used to extract the symptom clusters. RESULTS: Both the number and types of symptom clusters were similar using symptom occurrence rates or symptom severity ratings. Five symptom clusters were identified using symptom occurrence rates (i.e., psychological, hormonal, nutritional, gastrointestinal, epithelial). Six symptom clusters (i.e., psychological, hormonal, nutritional, gastrointestinal, epithelial, chemotherapy neuropathy) were identified using symptom severity ratings. Across the two dimensions, the specific symptoms within each of the symptom clusters were similar. CONCLUSIONS: Identification of symptom clusters in patients with breast cancer may be useful in guiding symptom management interventions. Future studies are warranted to determine if symptom clusters remain stable over a cycle of CTX in patients with breast cancer.

Interagency and Commercial Collaboration During an Investigation of Chikungunya and Dengue Among Returning Travelers to the United States.

Public health investigations can require intensive collaboration between numerous governmental and nongovernmental organizations. We describe an investigation involving several governmental and nongovernmental partners that was successfully planned and performed in an organized, comprehensive, and timely manner with several governmental and nongovernmental partners.

Chikungunya and Dengue Virus Infections Among United States Community Service Volunteers Returning from the Dominican Republic, 2014.

Chikungunya spread throughout the Dominican Republic (DR) after the first identified laboratory-confirmed cases were reported in April 2014. In June 2014, a U.S.-based service organization operating in the DR reported chikungunya-like illnesses among several staff. We assessed the incidence of chikungunya virus (CHIKV) and dengue virus (DENV) infection and illnesses and evaluated adherence to mosquito avoidance measures among volunteers/staff deployed in the DR who returned to the United States during July-August 2014. Investigation participants completed a questionnaire that collected information on demographics, medical history, self-reported illnesses, and mosquito exposures and avoidance behaviors and provided serum for CHIKV and DENV diagnostic testing by reverse transcription polymerase chain reaction and IgM enzyme-linked immunosorbent assay. Of 102 participants, 42 (41%) had evidence of recent CHIKV infection and two (2%) had evidence of recent DENV infection. Of the 41 participants with evidence of recent CHIKV infection only, 39 (95%) reported fever, 37 (90%) reported rash, and 37 (90%) reported joint pain during their assignment. All attended the organization's health trainings, and 89 (87%) sought a pretravel health consultation. Most (∼95%) used insect repellent; however, only 30% applied it multiple times daily and < 5% stayed in housing with window/door screens. In sum, CHIKV infections were common among these volunteers during the 2014 chikungunya epidemic in the DR. Despite high levels of preparation, reported adherence to mosquito avoidance measures were inconsistent. Clinicians should discuss chikungunya with travelers visiting areas with ongoing CHIKV outbreaks and should consider chikungunya when diagnosing febrile illnesses in travelers returning from affected areas.

Variations in potassium channel genes are associated with breast pain in women prior to breast cancer surgery.

Preoperative breast pain in women with breast cancer may result from a number of causes. Previous work from our team found that breast pain occurred in 28.2% of women (n = 398) who were about to undergo breast cancer surgery. The occurrence of preoperative breast pain was associated with a number of demographic and clinical characteristics, as well as variation in two cytokine genes. Given that ion channels regulate excitability of sensory neurons, we hypothesized that variations in potassium channel genes would be associated with preoperative breast pain in these patients. Therefore, in this study, we evaluated for associations between single-nucleotide polymorphisms and inferred haplotypes among 10 potassium channel genes and the occurrence of preoperative breast pain in patients scheduled to undergo breast cancer surgery. Multivariable logistic regression analyses were used to identify those genetic variations that were associated with the occurrence of preoperative breast pain while controlling for age and genomic estimates of and self-reported race/ethnicity. Variations in four potassium channel genes: (1) potassium voltage-gated channel, delayed rectifier, subfamily S, member 1 (KCNS1); (2) potassium inwardly rectifying channel, subfamily J, member 3 (KCNJ3); (3) KCNJ6; and (4) potassium channel, subfamily K, member 9 (KCNK9) were associated with the occurrence of breast pain. Findings from this study warrant replication in an independent sample of women who report breast pain following one or more breast biopsies.