Anemia Is a Predictor of Withdrawal from Peritoneal Dialysis in Stable Peritoneal Dialysis Patients

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This Japanese retrospective study examined the association between low hemoglobin levels (less than 11 g/dL) and peritoneal dialysis (PD) patient outcomes. Utilizing the Cox proportional hazards analysis, the study revealed that low hemoglobin levels were significant predictors of PD technical failure and subsequent transition to hemodialysis.

 

The manuscript is clear and particularly relevant for the field of home dialysis, especially peritoneal dialysis, a relatively under-researched area in nephrology. It is presented in a well-organized and classical structured manner. The references cited are mostly recent and objective, with no indication of self-citation.

 

The manuscript is scientifically sound, and the study design is appropriate for testing the hypothesis that anemia plays a role in the pathophysiology of peritoneum fibrosis. However, it is important to note the limitations described below.

 

A thorough review of the study reveals three notable limitations. Firstly, peritonitis is not acknowledged as a primary contributing factor to PD technical failure in the introduction. Secondly, peritonitis is absent from Table 1, which delineates the demographic characteristics of patients according to their hemoglobin levels. Thirdly, and most importantly, peritonitis is not examined as a variable (possibly contributing to PD technical failure) in theCox proportional hazards analysis. It is therefore recommended that authors in the Cox model first analyze peritonitis as present or absent, and that subsequent analysis be performed according to the number of peritonitis cases: 1, 2, 3, 4, and more than 4 since DP initiation, or with another valid method to quantify peritonitis rate.

 

If authors incorporate peritonitis into their Cox proportional hazards analysis, the study will likely be reproducible and the conclusions will be adequate.

 

The inclusion of figures and tables appears appropriate.

Comments on the Quality of English Language

To ensure the highest quality of the manuscript, it is recommended that the English wording be analyzed by a native English-American translator.

Author Response

Please see the attached file.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors made a retrospective study to evaluate the impact of hemoglobin level and PD withdrawal.  They found with statistical analysis that anemia is associated with PD withdrawal. These are interesting findings, but it is not clear why were PD treatment stopped and changed modality while both groups of patients (>11.0 Hb and <11 Hb) had equal kT/ results and, of course, no significant difference. What was the indication of the withdrawal of PD? The authors should clarify. Although the reasons are mentioned in Table 3, presenting the PET results before the withdrawal would also be essential.

The decline of the residual renal function is not an indication of stopping PD treatment. The results obtained suggest the opposite; underdialysis status led to the development of anemia, and not vice versa. For example, phosphate concentration was significantly higher in the <11 Hb group. Therapy-resistant anemia may be a marker in PD treatment, which may predict the ineffectiveness of PD treatment. The analogy is similar in hemodialysis, where underdialysis causes EPO resistance. 

The authors suggest that anemia is a risk factor for discontinuing peritoneal dialysis (PD) treatment, but that statement is inaccurate. PD treatment should only be halted if it is ineffective or if there is a need to change the treatment modality. When PD is ineffective, it can lead to worsening uremia, which in turn causes resistance to erythropoietin and exacerbates anemia. Therefore, anemia may actually serve as a predictor of premature discontinuation of PD treatment. 

The authors' study is worth considering, but I would definitely recommend reconsideration.

Author Response

Please see the attached file.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

This revised version, which has taken into consideration reviewer's comments, is now suitable for publication in the Journal.

Author Response

Comment: This revised version, which has taken into consideration reviewer's comments, is now suitable for publication in the Journal.

Response: Thank you for your positive comments. Thanks to the reviewers' suggestions, the quality of the manuscript has improved significantly.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors almost answered the raised questions. They improved their manuscript. I'm still not in agreement with the title because it is misleading. I would like to recommend "Anemia predicts for withdrawal from peritoneal dialysis in stable peritoneal dialysis patients". Overall, anemia does not lead to withdrawal from peritoneal dialysis. 

Author Response

Comment: The authors almost answered the raised questions. They improved their manuscript. I'm still not in agreement with the title because it is misleading. I would like to recommend "Anemia predicts for withdrawal from peritoneal dialysis in stable peritoneal dialysis patients". Overall, anemia does not lead to withdrawal from peritoneal dialysis. 

Response: Thank you for the re-review of our manuscript. As pointed out by the reviewer, the title we presented may be misleading. Following the reviewer’s suggestion, we have revised the title and the content of the abstract.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

Finally, the authors reached the best version of their manuscript. I have no more questions. 

Author Response

Comment: Finally, the authors reached the best version of their manuscript. I have no more questions. 

Response: Thank you for your positive comments. Thanks to the reviewers' suggestions, the quality of the manuscript has improved significantly.