Reviewer's report
Title:Socioeconomic status and mortality among cirrhosis patients: A Danish
nationwide cohort study
Version: 1Date:20 February 2009
Reviewer: Mats Ramstedt
Reviewer's report:
General remarks
This study addresses the question of whether low socioeconomic status is
associated with worse prognosis after cirrhosis diagnosis, which has been found
for several other alcohol-related diseases. As indicators of socioeconomic status
the authors use marital status, employment and personal income.
In order to examine this question, a population based cohort study with 5-year
follow up of 1765 Danish cirrhosis patients diagnosed in 1999-2001 was
conducted. Estimation of Cox-regression models (controlling for substance
abuse, co-morbidity etc.) showed that being divorced and a disability pensioner
were significantly associated with lower survival after 5 years but not
unemployment and low income.
To reveal a prognostic value of some socioeconomic conditions is certainly
valuable information and the statistical analysis seems sound. A weakness of the
study is however that the mechanisms behind these statistical associations
remain unclear, and that a theoretical rationale for assuming a link between
socioeconomic status is missing or is at least rather weak.
Major comments
" A definition of the concept socioeconomic status is lacking as well as a
discussion of how it is assumed to affect the likelihood of survival after cirrhosis
diagnosis. In what respect is marital status a socioeconomic condition and what
is the connection with social support (as it is called in the discussion, p 11)?
" The findings indicate that something about being divorced and being disabled
worsens the prognosis for cirrhosis patients but the authors fail to bring up
possible mechanisms except from the possibility that they would be "less
compliant with doctors advice to stop drinking" and then some general
statements of "range of behavioural, psychological, social and biological
mechanisms..". It seems that some more ambitious attempts to explain the
results are warranted, e.g. the general state of health (mental and somatic)
compared to the other groups?
Minor comments
" None of the studies cited for the statement that there is link between low
socioeconomic status and cirrhosis are based on Danish data. If this has not
been examined previously with Danish data that could be stressed as a rationale
for this study, not the least since the Danish welfare system aims at reducing
socioeconomic deífferences in health.
" The cause of death during follow-up would have been interesting information,
why was that not reported?
" The income measure was fairly rough; were there any indications that a more
detailed measure would have changed the importance of income, which
appeared important in other studies?
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interest
Reviewer's report
Title:Socioeconomic status and mortality among cirrhosis patients: A Danish
nationwide cohort study
Version: 1Date:20 February 2009
Reviewer: Mats Ramstedt
Reviewer's report:
General remarks
This study addresses the question of whether low socioeconomic status is
associated with worse prognosis after cirrhosis diagnosis, which has been found
for several other alcohol-related diseases. As indicators of socioeconomic status
the authors use marital status, employment and personal income.
In order to examine this question, a population based cohort study with 5-year
follow up of 1765 Danish cirrhosis patients diagnosed in 1999-2001 was
conducted. Estimation of Cox-regression models (controlling for substance
abuse, co-morbidity etc.) showed that being divorced and a disability pensioner
were significantly associated with lower survival after 5 years but not
unemployment and low income.
To reveal a prognostic value of some socioeconomic conditions is certainly
valuable information and the statistical analysis seems sound. A weakness of the
study is however that the mechanisms behind these statistical associations
remain unclear, and that a theoretical rationale for assuming a link between
socioeconomic status is missing or is at least rather weak.
Major comments
" A definition of the concept socioeconomic status is lacking as well as a
discussion of how it is assumed to affect the likelihood of survival after cirrhosis
diagnosis. In what respect is marital status a socioeconomic condition and what
is the connection with social support (as it is called in the discussion, p 11)?
" The findings indicate that something about being divorced and being disabled
worsens the prognosis for cirrhosis patients but the authors fail to bring up
possible mechanisms except from the possibility that they would be "less
compliant with doctors advice to stop drinking" and then some general
statements of "range of behavioural, psychological, social and biological
mechanisms..". It seems that some more ambitious attempts to explain the
results are warranted, e.g. the general state of health (mental and somatic)
compared to the other groups?
Minor comments
" None of the studies cited for the statement that there is link between low
socioeconomic status and cirrhosis are based on Danish data. If this has not
been examined previously with Danish data that could be stressed as a rationale
for this study, not the least since the Danish welfare system aims at reducing
socioeconomic deífferences in health.
" The cause of death during follow-up would have been interesting information,
why was that not reported?
" The income measure was fairly rough; were there any indications that a more
detailed measure would have changed the importance of income, which
appeared important in other studies?
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interest
Please review this paper.
user
Reviewer's report
Title:Socioeconomic status and mortality among cirrhosis patients: A Danish
nationwide cohort study
Version: 1Date:20 February 2009
Reviewer: Mats Ramstedt
Reviewer's report:
General remarks
This study addresses the question of whether low socioeconomic status is
associated with worse prognosis after cirrhosis diagnosis, which has been found
for several other alcohol-related diseases. As indicators of socioeconomic status
the authors use marital status, employment and personal income.
In order to examine this question, a population based cohort study with 5-year
follow up of 1765 Danish cirrhosis patients diagnosed in 1999-2001 was
conducted. Estimation of Cox-regression models (controlling for substance
abuse, co-morbidity etc.) showed that being divorced and a disability pensioner
were significantly associated with lower survival after 5 years but not
unemployment and low income.
To reveal a prognostic value of some socioeconomic conditions is certainly
valuable information and the statistical analysis seems sound. A weakness of the
study is however that the mechanisms behind these statistical associations
remain unclear, and that a theoretical rationale for assuming a link between
socioeconomic status is missing or is at least rather weak.
Major comments
" A definition of the concept socioeconomic status is lacking as well as a
discussion of how it is assumed to affect the likelihood of survival after cirrhosis
diagnosis. In what respect is marital status a socioeconomic condition and what
is the connection with social support (as it is called in the discussion, p 11)?
" The findings indicate that something about being divorced and being disabled
worsens the prognosis for cirrhosis patients but the authors fail to bring up
possible mechanisms except from the possibility that they would be "less
compliant with doctors advice to stop drinking" and then some general
statements of "range of behavioural, psychological, social and biological
mechanisms..". It seems that some more ambitious attempts to explain the
results are warranted, e.g. the general state of health (mental and somatic)
compared to the other groups?
Minor comments
" None of the studies cited for the statement that there is link between low
socioeconomic status and cirrhosis are based on Danish data. If this has not
been examined previously with Danish data that could be stressed as a rationale
for this study, not the least since the Danish welfare system aims at reducing
socioeconomic deífferences in health.
" The cause of death during follow-up would have been interesting information,
why was that not reported?
" The income measure was fairly rough; were there any indications that a more
detailed measure would have changed the importance of income, which
appeared important in other studies?
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interest
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