PONE-D-20-13895

Serum uric acid and risk of chronic kidney disease in normotensive, normoglycemic, and non-obese individuals

PLOS ONE

Dear Dr.  Se Won Oh 

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

It would be important for the authors to try to revise the comments made by this editor and regarding the statistics observed by one of the referees with whom I agree that it will certainly improve the study.

The study was well conducted but the authors need to analyze some points that I consider to be important in the manuscript, and that, if modified, will contribute to improving the text. Suggestions:

- the summary would need to be reformulated as it does not make it clear that it isis a follow-up study;

- in methods it would be necessary to describe the power of the sample used in the study and also it is important to describe in the results all the variables used;

- what were the analyzes carried out in order to verify if the ANOVA test is suitable for the study, and it would also be important to consider if the results obtained do not depend only on the high number of individuals collected in the study, therefore, they are really representative of the studied population, and,  

- when looking for risk calculation I believe it is better to use logistic regression analysis.

I hope that the authors will consider the suggestions made by the referees and this editor revising the manuscript..

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We look forward to receiving your revised manuscript.

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Dulce Elena Casarini, PhD, FAHA

Academic Editor

PLOS ONE

Additional Editor Comments:

The study was well conducted but the authors need to analyze some points that I consider to be important in the manuscript, and that, if modified, will contribute to improving the text.

Suggestions:

- the summary would need to be reformulated as it does not make it clear that it isis a follow-up study;

- in methods it would be necessary to describe the power of the sample used in the study and also it is important to describe in the results all the variables used;

- what were the analyzes carried out in order to verify if the ANOVA test is suitable for the study, and it would also be important to consider if the results obtained do not depend only on the high number of individuals collected in the study, therefore, they are really representative of the studied population, and,

- when looking for risk calculation I believe it is better to use logistic regression analysis.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: No

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Dear authors

Congratulations

You -the authors of the current research studied the association between serum uric acid levels and declining of renal function in individuals without comorbidities from Korea. You observed that SUA is an independent risk factor for declining eGFR, even in individuals with a normal range of renal function and without metabolic disorder. Despite being a retrospective study, you show interesting data showing the relationship that was the objective of the current research.

But, I need to make some small comments, such as...

In page 4

materials and methods

-It is necessary a figure with flowchart showing enrolment and exclusion criterias of individuals in this study.

In page 7; the results part

Higher SUA related to worse renal outcomes

I guess is better to describe:

-When risks were adjusted by multiple factors, the highest quartiles of SUA showed significant risks of 3.7 fold in eGFR decline compared to corresponding risk of the lowest quartile (RR: 3.701, 95% CI: 1.504-9.108).

-It is correct to assume that "...highest SUA quartile had a 2.222-fold (95% CI: 1.182-4.177, P =0.013) increase in risk for incident CKD...".

I see that is better "...highest quartile had a 2.2 fold (95% CI: 1.182-4.177) increase in risk for incident chronic kidneyd isease (CKD)".

Reviewer #2: This is an interesting paper and appears to have approached an important question regarding whether high levels of uric acid can be associated with loss in the renal function in adult population. However, there are several important issues that require clarification.

1) The title does not reflect the findings of the manuscript. It is not clear that this is a follow-up study. After the follow-up, there are already hypertensive and metabolically unhealthy individuals. Therefore, the title is inappropriate.

2) Please, do not use abbreviations in the summary section

3) The summary is not adequate. It is not clear in the aim section that this is a follow-up study.

4) Describe how the patients were recruited so that the reader can determine how representative this sample is of the population. For example, were these consecutive patients presenting to the Center?

5) Blood pressure data cannot be represented in decimals, please correct.

6) In the methodology section, it is important to describe all the variables present in the results.

7) Were normality tests performed?

8) How was the body fat percentage obtained?

9) What diagnostics were done to check that ANOVA fit and that results were not dependent on only the high number of individuals?

10) Wouldn't it be more informative to examine the baseline data by correlation analysis.

11) In Table 1, it appears that many variables do not show a linear trend across the quartiles of uric acid (e.g. Hb, AST, ALT, ALP, bilirubin, protein, albumin, glucose). This contradicts the claim that there is a linear trend (P < 0.001).

12) It would be more appropriate to perform logistic regression for the risk calculation

13) It would be appropriate to perform Poisson Regression

14) Results (Figures): The graphic quality is very poor.

15) The discussion section is very simple and could be better detailed.

16) The conclusion is confusing and speculative.

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Reviewer #1: No

Reviewer #2: No

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The effect of baseline serum uric acid on chronic kidney disease in normotensive, normoglycemic, and non-obese individuals: A health checkup cohort study

PONE-D-20-13895R1

Dear Dr. Oh,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Cheng Hu

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors answered all doubts and questions made to them about the current manuscript. The authors aligned the title with the objectives and the conclusion. They made a new chart. They managed to mitigate the statistical deficiency. They managed to improve the discussion of the manuscript. In my opinion, the manuscript is now ready to be published.

Reviewer #2: (No Response)

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No