Cardiometabolic disorders, inflammation and the incidence of non-alcoholic fatty liver disease: A longitudinal study comparing lean and non-lean individuals

Ehimen C. Aneni; Gul Jana Saeed; Marcio Sommer Bittencourt; Miguel Cainzos-Achirica; Chukwuemeka U. Osondu; Matthew Budoff; Edison R. Parise; Raul D. Santos; Khurram Nasir

doi:10.1371/journal.pone.0266505

Peer Review History

Original SubmissionApril 2, 2021
2 Aug 2021 Decision Letter - Martin Senechal, Editor PONE-D-21-09198 Cardiometabolic Disorders, Inflammation and the Incidence of Non-Alcoholic Fatty Liver Disease: A Longitudinal Study Comparing Lean and Non-lean Individuals PLOS ONE Dear Dr. Aneni, 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. Please submit your revised manuscript by Sep 16 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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When you resubmit, please ensure that you provide the correct grant numbers for the awards you received for your study in the ‘Funding Information’ section. 4. We note that you have stated that you will provide repository information for your data at acceptance. Should your manuscript be accepted for publication, we will hold it until you provide the relevant accession numbers or DOIs necessary to access your data. If you wish to make changes to your Data Availability statement, please describe these changes in your cover letter and we will update your Data Availability statement to reflect the information you provide. [Note: HTML markup is below. Please do not edit.] 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 ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ****** 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: No ****** 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 ****** 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) Editor Comments: -What is the rationale for choosing 150 METs/min /week? -METs and minutes per week are used interchangeably. Since they are not the same, please clarify what has been used. Is it 150 minutes/week of PA or 150 METs per week or 150METs/min/week. This need clarification. -Why the author excluded participants with a BMI under 18 (kg/m2). Is there a rationale for NAFLD? -Did the author kept only people with Data for NAFLD at baseline AND follow up? This needs to be clarified as well as how many people lost for these variables. -I encourage the author to look at the checklist of the STROBE and address each point. For example, inclusion criteria and hypothesis should be in the manuscript or more precise. This is important since PLOS One Criteria require each study to be reported according to the appropriate guidelines. Reviewer #1: The current study evaluates cardiometabolic risk factors among lean and non-lean individuals who were followed for the development of NAFLD. The study showed some significant differences between cardiometabolic profile of lean and non-lean individuals that developed NAFLD during follow up. Few comments: 1. It seems like participants were followed every 6months to one year. It is not clear why patients underwent hepatic USG at every visit? Was it based on clinical indication or specific criterias or all the participants underwent as part of screening protocol 2. Abstract: “In lean individuals, AD, elevated blood glucose and elevated BP were significantly associated with NAFLD”. Table 4 should elevated glucose was not associated with NAFLD among lean individuals in adjusted model whereas elevated BP and AD were. 3. Page 16, paragraph 1st: “We created 2 models: the first was unadjusted, the second was adjusted for age, sex, cigarette smoking, use of lipid lowering medication (all exposure groups), abdominal circumference (all exposure groups except physical inactivity)”. Abdominal circumference was an important association among lean individuals that developed NAFLD during follow up. Not sure why physical activity was excluded in this analysis, perhaps related to lack of association in lean individuals. 4. Please provide a flow sheet for exclusions for better presentation 5. Page 24, paragraph 2nd: “In univariate analysis, elevated BP was associated with greater than 2-fold risk in NAFLD which remained statistically significant even after controlling for likely confounders (IRR 1.40 [95%: 1.13 – 1.73])”. In table 3, elevated blood pressure lost statistical significance after adjusting for cofounders 1.19 (0.96-1.48) 6. Page 25, paragraph 1st: “However, in nonlean individuals, decreased physical activity was associated with incident NAFLD in both univariate and multivariate analysis (adjusted IRR 1.32 [ 95% CI: 1.14 – 1.54]). See table 5”. I am guessing the authors are referring to table 4 in this paragraph. 7. Page 28, paragraph 2nd: “The present study, which has significantly higher sample size (over 3000 lean participants), shows that in addition to elevated blood glucose, elevated BP and the presence of atherogenic dyslipidemia were independent risk factors for incident NAFLD among lean individuals”. According to table 4, elevated blood glucose was not associated with NAFLD among lean individuals in the adjusted model (1.45 (0.75 –2.79). ****** 6. 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 [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0266505.r001
Revision 1
1 Feb 2022 Author Response Response To Reviewers PONE-D-21-09198R1 Cardiometabolic Disorders, Inflammation and the Incidence of Non-Alcoholic Fatty Liver Disease: A Longitudinal Study Comparing Lean and Non-lean Individuals Editor’s Comments: -What is the rationale for choosing 150 METs/min /week? -METs and minutes per week are used interchangeably. Since they are not the same, please clarify what has been used. Is it 150 minutes/week of PA or 150 METs per week or 150METs/min/week. This need clarification. We thank the Editor for their comments. The correct measure is minutes/week of physical activity and not METs/min/week. 150 minutes/week was chosen because of the guideline recommendations of physical activity by several medical societies including the American Heart Association. We have corrected this error where applicable throughout the manuscript so that the text now reads as “minutes/ week” instead of “150METs/min/week”. We apologize for the error and subsequent confusion. -Why the author excluded participants with a BMI under 18 (kg/m2). Is there a rationale for NAFLD? We excluded individuals with BMI <18.5kg/m2¬. Persons with BMI below 18.5 are considered underweight. Underweight persons are more likely to have other chronic illnesses, including malignancies and other metabolic conditions that may introduce unmeasurable confounders. In addition, inclusion of underweight individuals would not be consistent with the definition of lean NAFLD – NAFLD in individuals with normal BMI. We have added a statement to this effect in the methods. -Did the author kept only people with Data for NAFLD at baseline AND follow up? This needs to be clarified as well as how many people lost for these variables. We thank the Editor for their question. The data selection is noted in the results section. Only individuals without NAFLD at baseline were included in this study. We have made this clearer by including a figure that details the participant flow and exclusion criteria and participant sizes for the study. I encourage the author to look at the checklist of the STROBE and address each point. For example, inclusion criteria and hypothesis should be in the manuscript or more precise. This is important since PLOS One Criteria require each study to be reported according to the appropriate guidelines. Again, we appreciate the insights shared by the Editor. We have made edits throughout the manuscript to align the manuscript with the STROBE criteria. We have also completed the STROBE checklist and included it in the Supplementary material. Reviewer #1: The current study evaluates cardiometabolic risk factors among lean and non-lean individuals who were followed for the development of NAFLD. The study showed some significant differences between cardiometabolic profile of lean and non-lean individuals that developed NAFLD during follow up. Few comments: 1.It seems like participants were followed every 6months to one year. It is not clear why patients underwent hepatic USG at every visit? Was it based on clinical indication or specific criterias or all the participants underwent as part of screening protocol? All participants underwent as hepatic ultrasound as a part of screening protocol. They did not need to meet other prespecified criteria. 2. Abstract: “In lean individuals, AD, elevated blood glucose and elevated BP were significantly associated with NAFLD”. Table 4 should elevated glucose was not associated with NAFLD among lean individuals in adjusted model whereas elevated BP and AD were. We thank the reviewer for their comment. We have now clarified this sentence in the abstract. “In lean individuals, AD, elevated blood glucose and elevated BP were significantly associated with NAFLD although for elevated blood glucose, statistical significance was lost after adjusting for possible confounders.” 3. Page 16, paragraph 1st: “We created 2 models: the first was unadjusted, the second was adjusted for age, sex, cigarette smoking, use of lipid lowering medication (all exposure groups), abdominal circumference (all exposure groups except physical inactivity)”. Abdominal circumference was an important association among lean individuals that developed NAFLD during follow up. Not sure why physical activity was excluded in this analysis, perhaps related to lack of association in lean individuals. We thank the reviewer for their comment. Our intent was to explain that waist circumference was excluded from our regression analysis only when Physical Activity was analyzed as the exposure. Physical Activity is known to prevent NAFLD and also it is known to reduce abdominal circumference. It is biologically plausible that abdominal circumference may be an intermediate in the pathway associating physical activity to NAFLD and adjusting for abdominal circumference in this exposure population is likely to lead to overadjustment. 4. Please provide a flow sheet for exclusions for better presentation We thank the reviewer for the suggestion. We have included a flowchart detailing the inclusion/ exclusion criteria for this study in the supplementary material. 5. Page 24, paragraph 2nd: “In univariate analysis, elevated BP was associated with greater than 2-fold risk in NAFLD which remained statistically significant even after controlling for likely confounders (IRR 1.40 [95%: 1.13 – 1.73])”. In table 3, elevated blood pressure lost statistical significance after adjusting for cofounders 1.19 (0.96-1.48) We thank the reviewers for this observation. We have corrected this typographical error. The first sentence in the results subsection on Blood pressure now reads as: “In univariate analysis, elevated BP was associated with greater than 2-fold risk in NAFLD but lost its significance after controlling for likely confounders (IRR: 1.19 [95%: 0.96 – 1.48])”. 6. Page 25, paragraph 1st: “However, in non-lean individuals, decreased physical activity was associated with incident NAFLD in both univariate and multivariate analysis (adjusted IRR 1.32 [ 95% CI: 1.14 – 1.54]). See table 5”. I am guessing the authors are referring to table 4 in this paragraph. We thank the reviewer for the observation. This is correct and we apologize for the error. We have corrected the appropriate text in the manuscript. The last sentence in the paragraph on page 19 now reads as: “However, in non-lean individuals, decreased physical activity was associated with incident NAFLD in both univariate and multivariate analysis (adjusted IRR 1.32 [ 95% CI: 1.14 – 1.54]) (See table 4).”. 7. Page 28, paragraph 2nd: “The present study, which has significantly higher sample size (over 3000 lean participants), shows that in addition to elevated blood glucose, elevated BP and the presence of atherogenic dyslipidemia were independent risk factors for incident NAFLD among lean individuals”. According to table 4, elevated blood glucose was not associated with NAFLD among lean individuals in the adjusted model (1.45 (0.75 –2.79). We thank the reviewer for their insightful comment. We have corrected this and it now reads “The present study, which has significantly higher sample size (over 3000 lean participants), shows that elevated BP and the presence of atherogenic dyslipidemia were independent risk factors for incident NAFLD among lean individuals. Blood glucose was not an independent risk factor for incident NAFLD in lean individuals.” Attachments Attachment Submitted filename: Response to Reviewers.pdf https://doi.org/10.1371/journal.pone.0266505.r002
23 Mar 2022 Decision Letter - Martin Senechal, Editor Cardiometabolic Disorders, Inflammation and the Incidence of Non-Alcoholic Fatty Liver Disease: A Longitudinal Study Comparing Lean and Non-lean Individuals PONE-D-21-09198R1 Dear Dr. Aneni, 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. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Martin Senechal, PhD Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0266505.r003
Formally Accepted
28 Mar 2022 Acceptance Letter - Martin Senechal, Editor PONE-D-21-09198R1 Cardiometabolic Disorders, Inflammation and the Incidence of Non-Alcoholic Fatty Liver Disease: A longitudinal study comparing lean and non-lean Individuals Dear Dr. Aneni: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Martin Senechal Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0266505.r004

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