Review for 10.1186/s12876-019-0950-z (2019)

Reviewer ’s report  
 
Title:  What is the impact of metabolic syndrome and its components on reflux esophagitis? A 
cross -sectional study  
 
Version: 0 Date: 01 Oct 2018 
 
Reviewer:  HC Lien 
 
Reviewer’s report:  
 
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This is a r etrospective cross -sectional study to investigate the correlation between reflux 
esophagitis and metabolic syndrome in Taiwanese adults undergoing health check. The authors 
found that 59.6% and 28.5% of study population had reflux esophagitis and metabolic  syndrome, 
respectively. In multivariate logistic regression analysis, age greater than 65, male gender, 
smoking, alcohol consumption, and metabolic syndrome are weakly associated with reflux 
esophagitis (all ORs < 2). In another model, they also found tha t 3 components of metabolic 
syndrome are also independently associated with reflux esophagitis, including abdominal 
obesity, elevated blood pressure, and hyperglycemia. In the trend analysis, they found that the 
severity of reflux esophagitis increased alo ng with the number of components of metabolic 
syndrome. They concluded that metabolic syndrome is associated with the severity of reflux 
esophagitis.  
 
The manuscript highlights an important issue of public health on reflux disease, of which 
metabolic syndr ome is undoubtedly a potential cause, although similar concept has been reported 
in several Asian studies cited in the references of this manuscript.  The novelty of this study is to 
find the association between each component of metabolic syndrome and ref lux esophagitis as 
well as a dose -response relation between the severity of esophagitis and the number of 
component of metabolic syndrome. These are considered as environmental factors for future 
intervention.  
 
 
Major concerns  
 
1. A unusually high prevalenc e of reflux esophagitis found in this study sample may imply a 
special study population. Therefore, the author should describe more in details of the 
study population, such as comorbidities, comedications (e.g. NSAID) , social economic 
status, and life sty les etc, which should be listed in Table 1.  
 
2. Another possible explanation for the high prevalence of reflux esophagitis is the 
overdiagnosis. Therefore the authors should report the prevalence of reflux symptoms in 
this population if possible as well as the reliability of the endoscopic diagnosis of reflux 
esophagitis.  Should the authors also report other relevant endoscopic findings such as 
hiatal hernia, peptic ulcer disease, and H. pylori?  
 
3. Both smoking and alcohol are associated with reflux esophagitis in this study, however, 
their definiti on and prevalence were not reported as the potentially important 
confounders.  
 
4. One important finding of this study is the association between the severity of reflux 
esophagitis and the number of component of metabolic syndrome. However, it would be 
more clear if the author can report the odds ratios with adjustments to demonstrate a 
dose-response relation, instead of the trend test analysis alone. Similarly, a dose -response 
relation can be showed to demonstrate the odds ratios of reflux esophagitis in dif ferent 
number of component of metabolic syndrome, using 0 component as reference.  
 
 
Minor concerns:  
 
1. Table 1 & Table 2 are considerably overlapping and should be merged.  
 
2. Table 3 & Table 4 are also overlapping and should be merged if possible. Besides, BMI 
should be one of the independent factors in the models.  
 
3. The text of the results should be avoided to duplicate the content of Tables.  
 
4. What is the meaning of " Second, the individuals with RE were not evenly distributed 
among the groups with LA gr ade A, B, and C, which may also have led to selection bias 
and influenced the study results." In the discussion page 17?  
 
5. The authors should clarify the definitions of elevated TG and reduced HDL -C. Do they 
include the anti -dyslipidemia medication use?  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
No 
 
Are you able to assess any statistics in the manuscript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further 
assessment in your comments to the editors.  
 
I recommend additional statistical review  
 
Quality of written English  
Please i ndicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, fun ding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from t he publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the  above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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