Response

Abstract

We appreciate Dr. Kawada for your attention on our article and thanks for your comments. We agree that “risk estimation by logistic regression analysis was unstable which was predominant in ECOG score,” and the main reason lies in less samples of subgroup 3. We will enlarge the samples in the following study. Second, cluster type and composition depends on the populations, disease stage, assessment method (e.g., symptom domain, chronology, and symptom wording), instrument, timeframe, and statistical method. Different symptom clusters may also occur due to the cancer or a result of antitumor treatment. At present, the cluster methodology is not well established, and limited research data provide some methodological guidance. A consensus around any statistical methodology employed should be established. In addition, for cluster validation, symptom numbers, dimensions, timeframe, and scales are to be explicit and uniform.1Kirkova J. Walsh D. Aktas A. et al.Cancer symptom clusters: old concept but new data.Am J Hosp Palliat Care. 2010; 27: 282-288Crossref PubMed Scopus (64) Google Scholar In our study, the four symptoms were chosen because of their high prevalence in cancer patients in our previous studies and other studies. While these symptoms can occur singly, they often co-occur as a cluster.2Barsevick A.M. The elusive concept of the symptom cluster.Oncol Nurs Forum. 2007; 34: 971-980Crossref PubMed Scopus (122) Google Scholar, 3Pud D. Ben Ami S. Cooper B.A. et al.The symptom experience of oncology outpatients has a different impact on quality-of-life outcomes.J Pain Symptom Manage. 2008; 35: 162-170Abstract Full Text Full Text PDF PubMed Scopus (106) Google Scholar, 4Chen M.L. Tseng H.C. Symptom clusters in cancer patients.Support Care Cancer. 2006; 14: 825-830Crossref PubMed Scopus (145) Google Scholar In addition, we did not assess these symptoms, for example, nausea, vomiting, loss of appetite, dyspnea, and so forth, and collect information about the other routine lab, for example, hemoglobin, hematocrit, and electrolyte level, because we mainly considered the patients' experiences with the symptom cluster of pain, fatigue, depression, and sleep disturbance. We will compare theses symptoms and lab data among three subgroups, and also try to replicate the cluster in the follow-up study. Finally, it is not surprising that urban residence was negatively associated with patients in subgroup 3. Patients who lived in urban had better economic status and good health insurance and also be more likely to access better medical resources than rural patients. Thanks again for your valuable suggestions. Yours sincerely, The corresponding author thanks other authors for assistance with data collection and analysis. None of the authors have any possible conflicts of interest to disclose. This project was funded in part by the Shandong Provincial Natural Science Foundation, China (grant no. 2015HM049). Re: Association of Inflammatory Cytokines With the Symptom Cluster of Pain, Fatigue, Depression, and Sleep Disturbance in Chinese Patients With CancerJournal of Pain and Symptom ManagementVol. 54Issue 6PreviewJi et al.1 examined the association between inflammatory cytokines and cluster symptoms on pain, fatigue, depression, and sleep disturbance in patients with cancer. Multiple logistic regression analysis was applied in 153 in-patients with cancer, comprising 125 patients with all low symptoms (Subgroup 1) and 28 patients with moderate-to-high symptoms on four items (Subgroup 3). Adjusted odds ratios (95% CIs) of Subgroup 3 against Subgroup 1 for increased serum interleukin-6 level and poorer Eastern Cooperative Oncology Group physical performance status were 1.246 (1.114–1.394) and 31.831 (6.017–168.385), respectively. Full-Text PDF Open Archive