Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
We thank the referees and the editor for the very detailed and helpful reviews. The comments of the
reviewers are displayed in Italics text. As the changes were substantial we have NOT highlighted the
changes we have made in the original manuscript. We also provide responses to each of the points raised
by the reviewers and the editor. As some comments were made by multiple reviewers, we have grouped
them. The changes made in the manuscript are also summarized.
Editor:
The reviewers have raised a number of methodological concerns that require extensive revisions to the
paper. In particular, a number of reviewers have raised concerns about analyzing depression and anxiety
together. Individuals with a depressive disorder, an anxiety disorder, or the comorbidity of a depression
and anxiety disorder are all very different. Analyzing these various disorders as a single entity is likely to
provide spurious results. We hope that by analyzing these disorders separately, some of the
methodological concerns can be alleviated.
Reviewer#1:
Anxiety and depression may each be uniquely associated with the various chronic physical health
conditions included in this study. In addition, the comorbid presence of depression and anxiety is likely
associated with a distinctly higher risk of chronic physical health conditions than either condition alone.
The researchers’ decision to collapse these two phenotypes into a single category is thus problematic,
and their rationale for doing so is not clear.
Reviewer#2:
Depression and anxiety, considered as mental health conditions, are quite different. Though they can cooccur, what is the rationale for combining depression and anxiety rather than examining them
separately?
Reviewer#3:
Combining depression and anxiety is not justified. These are two different conditions associated with
various comorbidities and treated with different therapies that may affect the medical comorbidities
differently. Authors should split these conditions.
Reviewer#4:
Considering the large sample size and the availability of a wide array of data, the authors may have
investigated more in depth the association under study. In particular, it would have been very interesting
to test whether the association between psychiatric disorders and chronic disease was mainly driven by
depressive, anxious or comorbid disorders.
Moreover, it would be interesting to report in the Results section not only the aggregate prevalence, but
also specific prevalence for depression, anxiety and comorbidity.
To address the concern of all four reviewers, we have reanalyzed the relationship between
depression-anxiety status and risk of chronic physical conditions by using a categorical variable
that distinguishes depression, anxiety, and comorbid depression and anxiety. In the revised
analysis, we have categorized non-elderly adults into 4 groups: 1) Depression only (individuals
with only depression and no anxiety); 2) Anxiety Only (individuals with only anxiety and no
depression); 3) Comorbid depression and anxiety (individuals with both depression and anxiety);
and 4) No depression and no anxiety (individuals with neither depression nor anxiety).
Page 1 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
Reviewer #2
Given the research described in the introduction, I’m surprised that the authors did not provide specific
hypotheses.
Reviewer #4
At the end of the introduction section the authors’ research hypotheses has to be explicitly expressed.
We agree with the reviewers and hypothesis has been stated at the end of the introduction
section in page 6.
Reviewer #2
More detail is needed on how depression and anxiety were coded. The manuscript states, “Presence of
either depression or anxiety was derived from medical conditions files” Yet, according to the methods
section, “extensive health care utilization data, including demographics, health conditions, health status,
use of medical care and prescription medications, detailed charges and payment, insurance coverage,
income, and employment are captured in the HC through annual computer-assisted in-person interviews
(CAPI). Clarification and greater detail are needed. If medical condition files were used for depression and
anxiety, why weren’t these files also used to determine the presence of chronic conditions given that selfreported medical conditions may be less reliable? If self-report was used for depression and anxiety, how
were participants asked about depression and anxiety? Wording for self-report items is crucial since the
extent to which depression and anxiety are represented as specific mood states versus mental health
conditions will be determined by the questions used.
Reviewer#3
The diagnoses of anxiety/depression are not clear. Provide the methods used to reach such diagnoses. If
self-reported, state what questions were asked to the study participants.
To address the concern of reviewer #2 and reviewer #3, we have provided greater details on
how medical conditions were captured in the MEPS. We also note that medical conditions files
were used for identifying chronic physical conditions as well as depression and anxiety. Please
see pages 7-8.
Reviewer #2
Related to the issue is the problem that data are not presented describing what % of normal, overweight
and obese participants reported depression, anxiety or both conditions? If more obese individuals report
both depression and anxiety, or report more depression than anxiety, this is notable and could influence
results. In this sample, 22% of obese individuals report depression and/or anxiety compared to 15% and
14% of normal and overweight individuals, which makes it likely that more obese individuals report both
depression and anxiety.
Reviewer #3
What is the association between BMI and depression? BMI and anxiety?
Reviewer #4
Moreover, no data about the relationship between depressive/anxious disorder and obesity in the
present sample is reported throughout the manuscript.
Page 2 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
To address the comments of reviewer #2 and reviewer #3, we now provide descriptive data on
proportions of normal, overweight, and obese participants reporting depression, anxiety, and
comorbid depression and anxiety. Please see page 10 and Table 1.
Reviewer #3
The authors should also state how BMI was measured, self-reported height and weight? If this is the
case, a major limitation is known in this approach as participants tend to under-report weight and
overestimate height.
Reviewer #4
The discussion lacks acknowledging serious limitations including the self-reported conditions and BMI.
BMI values were calculated by the survey investigators based on self –reported height and
weight. We now acknowledge the limitation of self-reported height and weight data in the
limitation section. Please see page 15.
REVIEWER #3
Why the results are not adjusted for psychotropic medications use? It seems the authors have access to
such data. Medications use may have a significant impact on the results.
REVIEWER #4
While addressing the major limitations of the lack of control for the impact of psychotropic medications
the authors stated that there is no evidence of any direct effect of such medications on the development
of asthma, arthritis or hypertension. However, recent evidence from a large cohort study (Licht et al. Biol
Psychiatry 2010 and Neuropsychopharmacology 2012) showed that antidepressant medications,
especially TCAs and SNRIs, were associated with lower heart rate variability (effects of TCA on HRV is
confirmed also in a recent meta-analysis, Kemp et al. Biol Psychiatry 2010 ) and increased sympathetic
tone. Moreover, epidemiological studies in older persons showed that use of antidepressants were
associated with fragility fractures and low bone mineral density even beyond the effects of depression
itself (Haney et al. Arch Int Med 2007, Richards et al. Arch Int Med 2007). Therefore the possible
influence of psychotropic medications on some of the investigated chronic diseases cannot be completely
ruled out without adequate adjustment.
We recognized that psychotropic medication use could have been controlled for in the analysis.
However, since we are controlling for depression and anxiety, controlling separately for use of
antidepressants, anti-anxiety drugs will raise the issue of multi-colinearity and therefore we did
not include psychotropic medication use as one of the independent variables.
Reviewer #1
The rationale for choosing a set of 9 chronic physical health conditions as the dependent variable is not
apparent. Although the association of depression/anxiety with all of these conditions does have
implications for health care costs and may suggest problems with primary care—a point that the authors
address in their Introduction and Discussion—they do not formally investigate either health care costs or
primary care utilization in their study.
Page 3 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
As noted by the reviewer, the current paper does not formally examine healthcare expenditures
or primary care use. According to the National Heart Lung and Blood institute reports
cardiovascular conditions, endocrine, nutritional and metabolic diseases, diseases of the
respiratory system and diseases of the musculoskeletal system were the top four mostly costly
diagnostic groups. Therefore we chose the most common cardiovascular conditions
(hypertension and heart disease), endocrine, nutritional and metabolic diseases (diabetes),
respiratory conditions (COPD and asthma) and musculoskeletal conditions (arthritis and
osteoporosis) as the chronic physical conditions of interest in our study.
We now provide the rationale for choosing the specific set of chronic physical conditions in page
8.
Reference:
National Heart, Lung and Blood Institute (NHBLI). 2012 Fact Book: Disease Statistics. 2012.
Available at: http://www.nhlbi.nih.gov/about/factbook/chapter4.htm
[Accessed on May 2 2013]
In addition, it is unclear how establishing an association of depression/anxiety with a diverse set of
chronic health conditions may help to design programs for depression/anxiety screening or implement
coordinated systems of care.
We agree with the reviewer that the study may not directly aid in designing programs for
depression/anxiety screening or implementing coordinated systems of care. The purpose of the
current study is to highlight the excess risk of chronic physical conditions associated with
depression-anxiety status and just to point out the need for coordinating mental health care
into primary care services.
The researchers appear to have tested as many as 90 statistical tests (45 in Table 3 and 45 in Table 4);
however, they do not report having used a Bonferroni (or other) correction against the inflated Type 1
error rate associated with conducting multiple tests.
We agree with the reviewer that because of a large number of hypothesis testing associated
with the study we can have an inflated Type I error rate. In the re-analysis we have 7 chronic
conditions and we are testing independent variable with 4 categories and thus 28 total
hypothesis tests. If we apply a Bonferroni correction the significance level is close to 0.002 (Pvalue=0.05/28=0.0017). However, except the association of osteoporosis with depression only
and anxiety only groups and association of diabetes with anxiety only group in Table 4 our
results are all significant at P-value <0.001. So we did not separately report Bonferroni
correction in the manuscript.
Reviewer #2
The discussion goes beyond the data. It is premature to call for routine screening of depression and
anxiety. The authors should temper their language.
We have done so. Please see page 12-14.
Page 4 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
The rationale for excluding underweight individuals by stating that they are more likely to be “sicker and
older” is not well supported given that the authors excluded adults over 65. According to the citation
provided, overweight individuals are also at greater risk for hospitalization and death, yet overweight
individuals were not excluded.
We appreciate the reviewer’s comment. However, underweight in adults (elderly/non-elderly)
may be due to an underlying chronic disease, treatment for chronic diseases like Cancer and
may consist of individuals who are both healthy and unhealthy. Therefore we excluded these
individuals. We have also eliminated the word “older”.
Why were back problems not included as one of the chronic conditions? Certainly back problems can be
associated with obesity.
We acknowledge that chronic pain and obesity are associated. However, we did not include
chronic back pain as one of the dependent variables because individuals with back pain has
been shown to be six times as likely as individuals with no chronic back pain to have prevalent
depression (PMID:14715389). However, to address the concern of the reviewer, we analyzed
the association between depression-anxiety status and chronic back pain. Chronic back was
identified with CCC codes 205 and ICD-9-CM codes 846 and 847. We found similar patterns of
association between depression-anxiety status and chronic back pain. The adjusted odds ratio
for comorbid depression and anxiety was 2.51 (95% CI: 2.13-2.95). For obesity, the AOR was
1.21(95% CI: 1.10-1.34). Because of the very close link between depression and pain, we do not
report these results in our manuscript.
Reference:
Currie SR, Wang J. Chronic back pain and major depression in the general Canadian population. Pain.
2004 Jan;107(1-2):54-60.
For the table 2, present the exact p-values, not asterisks denoting significance. The table should also
include the test statistic, at a minimum, if the test statistics are not provided in the text. Provide a note
with all acronyms. I assume ‘W.’ refers to ‘weighted’, but this should be noted.
We used asterisks for P-values as usually that is how significance is presented in scientific
journals. We made sure that all acronyms come with note.
Reviewer #3
The exclusions criteria are not well justified. For example, the authors excluded individuals with
diagnoses of schizophrenia, ADHD, Adjustment and personality disorders. What about bipolar disorder,
substance abuse/dependency, eating disorders, etc?
All individuals with diagnoses of schizophrenia, ADHD, adjustment and personality disorders and
substance abuse/dependency were excluded from analysis. In MEPS, ICD-9-CM condition codes
have been aggregated into clinically meaningful categories that group similar conditions using
Agency of Healthcare Quality (AHRQ) defined clinical classification codes (CCCODEX). The
Page 5 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
reported ICD-9-CM condition code values were mapped to the appropriate clinical classification
category prior to being collapsed to 3-digit ICD-9-CM condition codes. The result is that every
record which has an ICD-9-CM diagnosis code also has a clinical classification code. Since Bipolar
Disorder can only be identified using five digit ICD-9-CM condition codes we could not study
Bipolar Disorder. Eating disorders have been coded under ‘Miscellaneous disorders’. Since
Miscellaneous disorders category include other conditions like Sleep disorders and Sexual and
gender identify disorders, we could not separately exclude eating disorders.
The statistical analysis plan is not justified. Why divide the sample into 6 groups based on BMI? Why not
adjusting for BMI in the model?
We have done so.
The methods section, page 8, last paragraph, authors mentioned sensitivity analysis”. No sensitivity
analysis results were reported.
In the revised manuscript this section has been eliminated.
Why does osteoporosis behave differently than other chronic conditions? What is the impact of self-
report on these results?
The discussion lacks acknowledging serious limitations including why osteoporosis acts differently, why
overweight is a protective factor, just to mention few examples.
Over the past few decades, extensive data have shown that, in healthy pre-menopausal and
postmenopausal women, total body fat is positively related to bone mineral density, an
important and measurable determinant of fracture risk, that high body weight (or body mass
index) is correlated with high bone mineral density, and that decreased body weight leads to
bone loss (References 1-6). However, some recent evidences have indicated an inverse
relationship between obesity and osteoporosis depending on how obesity is defined. In the
studies where obesity is defined on the basis of body mass index or body weight, obesity
appears to act as a protective factor against bone loss and fractures; however, if obesity is
considered as a percentage of body fat and distribution, it becomes a risk factor for osteoporosis
(Reference 7). Since this study defined obesity with BMI, we cannot truly comment on the
protective effect of obesity on bone mass and osteoporosis.
References:
1. Melton LJ, III, Atkinson EJ, O’Fallon WM, Wahner HW, Riggs BL. Long-term fracture prediction by
bone mineral assessed at different skeletal sites. J Bone Miner Res. 1993;8:1227–1233.
2. Mazess RB, Barden HS, Ettinger M, et al. Spine and femur density using dual-photon absorptiometry
in US white women. Bone Miner Res. 1987;2:211–219.
3. Felson DT, Zhang Y, Hannan MT, Anderson JJ. Effects of weight and body mass index on bone mineral
density in men and women: The Framingham study. J Bone Miner Res. 1993;8:567–573.
4. Marcus R, Greendale G, Blunt BA, et al. Correlates of bone mineral density in the postmenopausal
estrogen/progestin interventions trial. J Bone Miner Res. 1994;9:1467–1476.
Page 6 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
5. Reid IR, Ames R, Evans MC, et al. Determinants of total body and regional bone mineral density in
normal postmenopausal women – a key role for fat mass. J Clin Endocrinol Metab. 1992;75:45–51.
6. Ravn P, Cizza G, Bjarnason NH, Thompson D, et al. Low body mass index is an important risk factor for
low bone mass and increased bone loss in early postmenopausal women. Early Postmenopausal
Intervention Cohort (EPIC) study group. J Bone Miner Res. 1999;14:1622–1627.
7. Migliaccio S, Greco EA, Fornari R, Donini LM, Lenzi A. Is obesity in women protective against
osteoporosis? Diabetes Metab Syndr Obes. 2011;4:273-82. doi:10.2147/DMSO.S11920. Epub 2011 Jul 4.
Table 2 missing “table 2”; Introduction can be shortened; Spaces between words are not consistent
throughout the manuscript; Introduction, page 3, last paragraph “could be used to explain the
relationship between depression and increased cardiac risk.” Cardiac risk for what?; Please replace
“mental conditions, mental illness” with psychiatric disorders.
As suggested by the reviewer, we have corrected, replaced, and inserted missing word.
Reviewer #4
Research background should be strengthened in two aspects. First of all, literature needs to be updated.
Recently, well-established evidence at the level of meta-analyses became available about the association
of depression with major physical conditions such as cardiovascular disorders, hypertension, stroke,
diabetes, Alzheimer’s disease and metabolic syndrome. This literature deserves to be referenced and
discussed. Then, although the present study examines the possible interrelationship between
depression/anxiety and obesity in determining major health outcomes, previous research concerning the
bidirectional association, and its underlying mechanisms, between depression and obesity (also with
specific type of obesity, such as abdominal obesity) is not reported. Again, meta-analytic studies on this
topic are also available. Finally, a discussion about the possible shared mechanism underlying the
complex relationship between affective disorders, obesity and physical diseases is warranted.
We have updated the literature review as suggested.
The authors described the design of the study as “retrospective cross-sectional”. However the timeframe
of the study, in particular the timing of ascertainment of the key predictors and outcomes, is not entirely
clear. The authors may want to clarify the following issues. The authors reported that the current study
utilized data from 2007 and 2009 waves of MEPS. Is there a particular reason for the selection of these
two specific waves (study started in 1996)? Since it is reported that a new sample is introduced every
year, why data from 2008 were not used? Moreover, the timing of ascertainment of investigated
conditions is particularly important especially for depression, given its recurrent nature. What is the time
frame of the reported prevalence? Is it the prevalence in the year of the study? Is it life-time prevalence?
If yes, is there any information on the recency of the last episodes or on the number of previous
episodes? In the same way, was BMI assessed at the time of the interview? It would be particularly
difficult to interpret the meaning of the findings for instance for a subject that had only one episodes of
major depression, completely remitted, several years ago.
It has to be noted that MEPS do not follow the same individuals since 1996. The survey is
designed to follow the same individuals for only two years. Every two years the panels are
Page 7 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
replenished with new sample of households. Therefore every alternate can be considered as
independent samples. For this reason we selected alternate years 2007 and 2009, rather than
consecutive years. Furthermore, these years were chosen because they were the most recent
years available when we began analysis on this paper.
With regard to BMI measurement, self-reported height and weight for the calendar year were
assessed during Round 3 interview.
The reviewer is correct in noting that depression, anxiety and chronic physical condition
prevalence are as of the year of the study.
Information on methodological aspects of the assessments are missing. BMI: was it ascertained trough
self-report, medical files or objectively measured? Information on depression/anxiety disorders was
derived from medical conditions files. However, it’s not clear what classifications system has been used
to identify these disorders (ICD, DSM?) and what disorders were included in these two broad categories
(specific disorders should be listed).
BMI is ascertained from self-reported height and weight values. Depression and anxiety was
coded based on ICD-9-CM classification. For more details on coding of depression and anxiety,
please see response to Reviewer 2 Comment 2. Specific prevalence for depression, anxiety and
comorbid depression and anxiety has been mentioned in paragraph 1 of results section.
In the statistical analyses section the authors reported (page. 8) that: “For Sensitivity analysis we also
carried out these two contrasts with binary multivariable logistic regressions”. It’s not entirely clear what
are the purpose and the implementation aspects of these analyses. Sensitivity analyses usually test
whether the results are sensitive to restrictions on the data included (e.g. restrictions to specific
subgroups or to more stringent criteria in the definition of outcomes). However, it appears that the main
difference between these analyses and those previously reported is the choice of the technique
(complementary log-log vs logistic), is this correct? If this is the case, the latter analyses do not convey
additional information as compared to the previous ones and could be dropped.
We have dropped the logistic regression results.
The authors reported also (page. 9): “All analyses accounted for the complex design of MEPS to ensure
that results were nationally representative.” Please, clarify what are the implications of this sentence.
The first stage of sample selection for MEPS is an area sample of primary sampling units (PSUs),
where PSUs generally consist of one or more counties. Within PSUs, density strata are formed,
generally reflecting the density of minority populations for single or groups of blocks or block
equivalents that are assigned to the strata. Within each such density stratum "super-segments"
are formed, consisting of clusters of housing units.” Data analyses have to account for the PSU
and strata within the survey structure, so that the percentages are nationally representative.
This was done using survey methods procedure of statistical analytic software (SAS).
The limitation of non-generalizability of the present findings to other age-groups (in particular to older
age when such chronic physical condition are more common) should be mentioned.
Page 8 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
We agree with the reviewer and this limitation has been acknowledged in the revised
manuscript.
In general, the paper is lengthy and likely could be sized down. Introduction and Discussion sections
include redundant wording and several accurate statements that are not well-connected. Finally,
although the paper is generally well-written, there are some English language usage issues that diminish
readability and comprehension.
We have tidied up both introduction and discussion section and the paper has been reviewed by
a medical writer to minimize grammatical errors and English language issue. We will appreciate
further comments.
The discussion of the possible mechanism underlying the association under study now present in the
introduction may be better placed in the discussion section. This may improve the fluency and the focus
of the introduction that is now a little scattered.
We have tidied up both introduction and discussion section.
At Page. 9 the acronym CLL is used without previous reference.
Corrected the without reference acronym use.
COMMENTS NO LONGER APPLICABLE
Reviewer #1
It is not clear whether the statistical analyses truly controlled for obesity. Rather, it seems that the
researchers tested an interaction term (i.e., the cross-product of BMI categories and presence or absence
of depression/anxiety) without including the main effects of BMI category and depression/anxiety.
This comment is no longer applicable as we have reanalyzed the data with emphasis on excess
risk of chronic physical conditions associated with depression-anxiety status after controlling for
modifiable lifestyle risk factors such as obesity, lack of physical activity and/or smoking.
Reviewer #2
The study aims and the interpretation of the results do not appear to match the analytic plan. The
authors state that they want to examine the additional contribution, beyond obesity, of depression or
anxiety to chronic health conditions. Yet the analyses, do not control for obesity, or compare obese
individuals to all other participants. Overweight individuals are separated from normal weight
individuals and the overweight comparisons are essentially ignored in the discussion of results. Since the
authors discuss their analysis as examining an “interaction,” (“The large number of observations allowed
us to analyze the interaction between BMI categories and presence or absence of depression and/or
anxiety”), it is unclear to why an interaction was not used in the analysis.
Page 9 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
This comment no longer applicable as we have reanalyzed the data with emphasis on excess risk
of chronic physical conditions associated with depression-anxiety status after controlling for
modifiable lifestyle risk factors such as obesity, lack of physical activity and/or smoking.
Discussion page 12, second paragraph contradicts the author’s conclusions: “Our results also indicated
that there were no significant differences in the risk of having diabetes or thyroid between “depression
and/or anxiety and normal BMI” and “no depression, no anxiety and normal BMI” groups. This finding
suggests that maintaining a normal BMI regardless of presence of depression and/or anxiety is critical in
preventing onset of chronic physical conditions.”
This comment is no longer applicable, as we have reanalyzed the data and have dropped thyroid
disorder from the list of examined chronic physical conditions.
Reviewer #3
Table 3. No dep/anx group who are overweight, it seems puzzling that being overweight is associated
with a protective effect of all (except osteoporosis) chronic conditions? This questions the validity of the
results.
This comment is no longer relevant as we have reanalyzed the data with emphasis on excess risk of
chronic physical conditions associated with depression-anxiety status after controlling for modifiable
lifestyle risk factors such as obesity, lack of physical activity and/or smoking.
The results tables. Table 1 shows that 45% of participants in the depression/anx group and normal BMI
to report their “perceived mental health” as excellent/very good. This is very strange. Similarly 43% of
the dep/anx group with overweight and 37% of the anx/dep obese group. Please explain.
This comment is no longer applicable because our key measure no longer measures the
interaction between BMI and depression and anxiety.
In the revised version, we did not include mental health status in our re-analysis because of the
strong relationship between depression-anxiety status and perceived mental health status.
Among individuals with excellent or very good mental health 91% reported neither depression
nor anxiety.
Reviewer #4
In the discussion and conclusions sections the authors stated that the present study analyzed the
interaction between depression and/or anxiety and BMI on the risk of having chronic physical conditions.
However, no formal testing of their interactive effect has been performed. In order to have a clearer and
more easily interpretable picture of the possible joint effect of psychiatric disorders and obesity, before
proceeding to stratified analyses with the group proposed in the current version of the paper, it would be
useful to perform the following analyses: test the effect of depression/anxiety and BMI separately, and
Page 10 of 11
Manuscript: 1924306071820074
BMC Psychiatry
Title: Excess Risk of Chronic Physical Conditions Associated with Obesity and Common Mental Health
Conditions: Depression and/or Anxiety
Authors: Rituparna Bhattacharya, Chan Shen, Usha Sambamoorthi
then test the significance of the depression/anxiety-by-BMI interaction term in a model already including
the depression/anxiety and BMI terms.
This comment is no longer applicable.
Page 11 of 11