Reviewer's report
Title:Gallstones associated with non-alcoholic fatty liver disease in female rather
than male: a longitudinal cohort study
Version:1Date:30 July 2014
Reviewer: Monica Acalovschi
Reviewer's report:
Comments to the Authors
The study Gallstones associated with non-alcoholic fatty liver disease in female
rather than male: a longitudinal cohort study by Jia Liu et al is an interesting
study performed on a large population aiming to confirm the increased incidence
of gallstones in NAFLD patients, an association documented mainly in
cross-sectional studies. The authors performed a longitudinal study of patients
with NAFLD. Following-up for 6 years a large group of subjects with and without
NAFLD, the authors found an incidence of gallstones in NAFLD patients of 12,73
per 1,000 persons-year, significantly higher than in non-NAFLD subjects.
Analyzing some of the known risk factors in subjects who developed gallstones,
the authors demonstrate that NAFLD is an independent risk factor for gallstone
disease.
Major comments:
1. The study population was recruited among individuals from one city in China
who attended a health screening and therefore may not represent the entire
community. I suggest adding in the title…. a longitudinal cohort study in a
Chinese urban population
2. I suggest introducing supplementary tables 1 and 2 as regular tables in the
text, so that readers may easier follow the frame of the study.
3. The number of subjects followed-up for 6 years was much lower than of those
who were examined 2 or 3 years due to different moments of enrolment starting
with 2005. How could this have influenced the study results?
4. Incidence of gallstones did not increase during follow-up after NAFLD
diagnosis, suggesting that age is not a predisposing factor for gallstones in
NAFLD patients. This is in contrast with studies in different populations and in
NAFLD patients (Fracanzani et al, 2012, Loria et al 2005), which described an
increasing percentage of gallstones with age. The authors should better explain
this finding.
5. Information regarding the family history of gallstones was not available. This
factor may act as confounding variable in the association between gallstones and
NAFLD, because heredity is an important risk factor for gallstone disease. This
aspect should be discussed by the authors.
6. The authors should state that the causal relationship between gallstones and
NAFLD could not be examined by this longitudinal study. However, the study
provides solid evidence that gallstones are associated with NAFLD in female
subjects, NAFLD being an independent risk factor for lithogenesis.
Minor comments:
Some spelling and grammar errors occur in the manuscript, which need to be
corrected by an English translator.
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
Declaration of competing interests:
I declare that I have no competing interests regarding this manuscript.
Reviewer's report
Title:Gallstones associated with non-alcoholic fatty liver disease in female rather
than male: a longitudinal cohort study
Version:1Date:30 July 2014
Reviewer: Monica Acalovschi
Reviewer's report:
Comments to the Authors
The study Gallstones associated with non-alcoholic fatty liver disease in female
rather than male: a longitudinal cohort study by Jia Liu et al is an interesting
study performed on a large population aiming to confirm the increased incidence
of gallstones in NAFLD patients, an association documented mainly in
cross-sectional studies. The authors performed a longitudinal study of patients
with NAFLD. Following-up for 6 years a large group of subjects with and without
NAFLD, the authors found an incidence of gallstones in NAFLD patients of 12,73
per 1,000 persons-year, significantly higher than in non-NAFLD subjects.
Analyzing some of the known risk factors in subjects who developed gallstones,
the authors demonstrate that NAFLD is an independent risk factor for gallstone
disease.
Major comments:
1. The study population was recruited among individuals from one city in China
who attended a health screening and therefore may not represent the entire
community. I suggest adding in the title…. a longitudinal cohort study in a
Chinese urban population
2. I suggest introducing supplementary tables 1 and 2 as regular tables in the
text, so that readers may easier follow the frame of the study.
3. The number of subjects followed-up for 6 years was much lower than of those
who were examined 2 or 3 years due to different moments of enrolment starting
with 2005. How could this have influenced the study results?
4. Incidence of gallstones did not increase during follow-up after NAFLD
diagnosis, suggesting that age is not a predisposing factor for gallstones in
NAFLD patients. This is in contrast with studies in different populations and in
NAFLD patients (Fracanzani et al, 2012, Loria et al 2005), which described an
increasing percentage of gallstones with age. The authors should better explain
this finding.
5. Information regarding the family history of gallstones was not available. This
factor may act as confounding variable in the association between gallstones and
NAFLD, because heredity is an important risk factor for gallstone disease. This
aspect should be discussed by the authors.
6. The authors should state that the causal relationship between gallstones and
NAFLD could not be examined by this longitudinal study. However, the study
provides solid evidence that gallstones are associated with NAFLD in female
subjects, NAFLD being an independent risk factor for lithogenesis.
Minor comments:
Some spelling and grammar errors occur in the manuscript, which need to be
corrected by an English translator.
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
Declaration of competing interests:
I declare that I have no competing interests regarding this manuscript.
Please review this paper.
user
Reviewer's report
Title:Gallstones associated with non-alcoholic fatty liver disease in female rather
than male: a longitudinal cohort study
Version:1Date:30 July 2014
Reviewer: Monica Acalovschi
Reviewer's report:
Comments to the Authors
The study Gallstones associated with non-alcoholic fatty liver disease in female
rather than male: a longitudinal cohort study by Jia Liu et al is an interesting
study performed on a large population aiming to confirm the increased incidence
of gallstones in NAFLD patients, an association documented mainly in
cross-sectional studies. The authors performed a longitudinal study of patients
with NAFLD. Following-up for 6 years a large group of subjects with and without
NAFLD, the authors found an incidence of gallstones in NAFLD patients of 12,73
per 1,000 persons-year, significantly higher than in non-NAFLD subjects.
Analyzing some of the known risk factors in subjects who developed gallstones,
the authors demonstrate that NAFLD is an independent risk factor for gallstone
disease.
Major comments:
1. The study population was recruited among individuals from one city in China
who attended a health screening and therefore may not represent the entire
community. I suggest adding in the title…. a longitudinal cohort study in a
Chinese urban population
2. I suggest introducing supplementary tables 1 and 2 as regular tables in the
text, so that readers may easier follow the frame of the study.
3. The number of subjects followed-up for 6 years was much lower than of those
who were examined 2 or 3 years due to different moments of enrolment starting
with 2005. How could this have influenced the study results?
4. Incidence of gallstones did not increase during follow-up after NAFLD
diagnosis, suggesting that age is not a predisposing factor for gallstones in
NAFLD patients. This is in contrast with studies in different populations and in
NAFLD patients (Fracanzani et al, 2012, Loria et al 2005), which described an
increasing percentage of gallstones with age. The authors should better explain
this finding.
5. Information regarding the family history of gallstones was not available. This
factor may act as confounding variable in the association between gallstones and
NAFLD, because heredity is an important risk factor for gallstone disease. This
aspect should be discussed by the authors.
6. The authors should state that the causal relationship between gallstones and
NAFLD could not be examined by this longitudinal study. However, the study
provides solid evidence that gallstones are associated with NAFLD in female
subjects, NAFLD being an independent risk factor for lithogenesis.
Minor comments:
Some spelling and grammar errors occur in the manuscript, which need to be
corrected by an English translator.
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
Declaration of competing interests:
I declare that I have no competing interests regarding this manuscript.
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