The Impact of Sleep on Haematological Parameters in Firefighters

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript ‘The Impact of Sleep on Haematological Parameters in Fire-fighters’ presents an unusual association of changes in hematological parameters and sleep patterns.

 

Specific comments:

(1)   The authors may present numerical values rather than just descriptions in the results section of the Abstract

(2)   The Introduction can begin with associations of sleep and established adverse health effects (obesity, insulin resistance and coronary artery disease), and then introduce the association of changes in hematological parameters. Specific reasons for studying active duty fire fighters may be mentioned

(3)   The language needs to be toned down; at places added descriptive words may be reduced: eg ‘Additionally studies suggest that..’

(4)   Considering the audience is knowledgeable about basic biology, explanations of common phenomenon can be pared down eg: ‘(Hb), a molecule with the ability to bind up with oxygen molecules’

(5)   Details of hematopoietic regulation may be reduced

(6)   It needs to be clarified that sleep can influence hematological parameters and that fire-fighters were recruited to study the effect. The two are separate

(7)   Results can be limited to highlighting significant numbers presented in the tables; attempts to dilate on the results are best left to the Discussion section

(8)   Did menstrual status have an effect on blood parameters?

(9)   Why was the consumption of coffee specifically studied as a variable?

(10)                 The Discussion can begin with a summary and focused account of the results in the present studied. The remainder can be presented in brief next.

(11)                 The results must be summarized, highlighting the salient observations. In the current form, the reader is swamped with information, which cannot be easily comprehended

(12)                 The various parameters were studied 24-48 hours after active fire-fighting duty. Could this have affected the blood parameters because of potential dehydration and physical and mental stress?

(13)                 When was the sleep questionnaire administered?

 

(14)                 What do the authors mean by ‘..quality. Such conditions can contribute to the development of haematological disorders’

Comments on the Quality of English Language

See comment (3) above

Author Response

Response to Reviewer 1

1. The authors may present numerical values rather than just descriptions in the results section of the Abstract

• Authors response: Thank you for the note. We have included numerical values in the results section of the Abstract where applicable to enhance clarity.

 

2. The Introduction can begin with associations of sleep and established adverse health effects (obesity, insulin resistance and coronary artery disease), and then introduce the association of changes in hematological parameters. Specific reasons for studying active duty fire fighters may be mentioned

• Authors response: Thank you for your feedback. We appreciate your suggestion to highlight the associations of sleep with established adverse health effects in the Introduction. We want to acknowledge that we have provided this information in lines 90 to 99 of our manuscript.

 

3. The language needs to be toned down; at places added descriptive words may be reduced: eg ‘Additionally studies suggest that..’.

• Authors response: We sincerely appreciate this feedback. We have reviewed throughout the manuscript to improve readability.

 

4. Considering the audience is knowledgeable about basic biology, explanations of common phenomenon can be pared down eg: ‘(Hb), a molecule with the ability to bind up with oxygen molecules’.

• Authors response: We sincerely appreciate this feedback.

 

5. Details of hematopoietic regulation may be reduced.

• Authors response: Thank you for this suggestion.

 

6. It needs to be clarified that sleep can influence hematological parameters and that firefighters were recruited to study the effect. The two are separate.

• Authors response: Thank you for this suggestion.

 

7. Results can be limited to highlighting significant numbers presented in the tables; attempts to dilate on the results are best left to the Discussion section.

• Authors response: We are grateful for this feedback.

 

8. Did menstrual status have an effect on blood parameters?

• Authors response: We appreciate this question. The effect of menstrual status on blood parameters has been addressed and is included in the manuscript.

 

9. Why was the consumption of coffee specifically studied as a variable?

• Authors response: Your point is well-taken. We have provided a rationale for studying coffee consumption as a variable in the manuscript.

 

10. The Discussion can begin with a summary and focused account of the results in the present studied. The remainder can be presented in brief next.

• Authors response: Thank you for this suggestion. The Discussion section has been revised to begin with a summary and focused account of the results from the present study, followed by a brief presentation of additional findings.

 

11. The results must be summarized, highlighting the salient observations. In the current form, the reader is swamped with information, which cannot be easily comprehended.

• Authors response: We are grateful for this feedback.

 

12. The various parameters were studied 24-48 hours after active firefighting duty. Could this have affected the blood parameters because of potential dehydration and physical and mental stress?

• Authors response: Your insight is valuable. The potential effects of firefighting duties on blood parameters studied 24-48 hours after active duty have been discussed.

 

13. When was the sleep questionnaire administered?

• Authors response: Thank you for raising this point. The timing of the data collection has been clarified in the manuscript.

Reviewer 2 Report

Comments and Suggestions for Authors

Authors evaluated the effects of sleep quality on haematological parameters (red blood cells count, haemoglobin concentration, haematocrit values) of 201 Portuguese fire-fighters. The influence of confounding factors (sex, age, body weight, smoking status, alcohol and coffee consumption) on blood parameters was also evaluated.

The paper is well written and interesting to read. Before publication, I suggest the following modifications:

Lines 80 and 83: please, replace “Epo” with “EPO”.
Line 81: “in at night”, the correct form is “at night”.
Line 116: the words “from which” are repeated.
Line 123 and Table 1: in the text it is stated that 49% of individuals were classified as above weight. But in the table, “Pre-obesity” group shows a percentage of 44%; the sum of percetages of “Pre-obesity”, “Obesity I”, “Obesity II” and “Obesity III” groups is 64%. Please, check if the value 49% is
correct.
Table 2: the data refers to a total of 220 individuals. But in the paragraph 2.1 it is stated that the total sample included 233 firefighters, and among them, only 201 individuals completed the PSQI questionnaire and were subjected to blood sampling. What are the characteristics of this group of 220 individuals?
Table 2: Column “Mean ± SD”. What values were used to calculate mean and SD? It is indicated neither in the text nor in the table caption.
Paragraph 2.3 “Haematological profile”: authors reported RBC, Hb and HCT mean values obtained for all the individuals (males + females). But adult males and females have different normal reference ranges; so please add in the text RBC, Hb and HCT mean values obtained for males and females separately, to provide more information to the reader.
Line 220: “as indicated by and F-statistic of 6.053”. Please remove “and”.
Lines 224, 231, 236: “β = …”. Please replace the comma with a point.
Lines 413 and 533: “et al.’s”. please remove “’s”.
Line 417: “Hg”. Probably it is “Hb”.
Lines 516-517. Normal Hb values for humans are: 12.0-16.0 g/dl for females and 14.0-18.0 g/dl for males (the values may vary depending on the population considered). Values described in the text, 147.00 and 139.00 g/dl Hb, are abnormal. I have checked the original paper (Malenica et al., 2017)
and the same values for Hb are reported (Table 2). I think there is a typing error in the original paper…

Please standardize the way the unit of measurement “g/dl” is written in the paper: “g/dl” or “g/dL”.
Line 630: the word “levels” is repeated.
Reference n. 51: please add authors and number of p

Author Response

Authors evaluated the effects of sleep quality on haematological parameters (red blood cells count, haemoglobin concentration, haematocrit values) of 201 Portuguese fire-fighters. The influence of confounding factors (sex, age, body weight, smoking status, alcohol and coffee consumption) on blood parameters was also evaluated.

The paper is well written and interesting to read. Before publication, I suggest the following modifications.

• Authors response: Thank you for your positive feedback on our manuscript.

 

1. From Correction errors and irregularities
1. Lines 80 and 83: Please replace “Epo” with “EPO”.
2. Line 81: “in at night”, the correct form is “at night”.
3. Lines 224, 231, 236: “β = …”. Please replace the comma with a point.
4. Lines 413 and 533: “et al.’s”. Please remove “’s”.
5. Line 417: “Hg”. Probably it is “Hb”.
6. Line 116: The words “from which” are repeated.
7. Line 220: “as indicated by and F-statistic of 6.053”. Please remove “and”.
8. Please standardize the way the unit of measurement “g/dl” is written in the paper: “g/dl” or “g/dL”.
9. Line 630: the word “levels” is repeated.
10. Reference n. 51: please add authors and number of p

• Authors response: Thank you for your attention to detail. We have addressed all the mentioned corrections.

1. Verification of Hemoglobin Values and Additional Information on Hematological Profile:

1. Paragraph 2.3 “Haematological profile”: Authors reported RBC, Hb, and HCT mean values obtained for all the individuals (males + females). But adult males and females have different normal reference ranges; so please add in the text RBC, Hb, and HCT mean values obtained for males and females separately, to provide more information to the reader.
2. Lines 516-517. Normal Hb values for humans are: 12.0-16.0 g/dl for females and 14.0-18.0 g/dl for males (the values may vary depending on the population considered). Values described in the text, 147.00 and 139.00 g/dl Hb, are abnormal. I have checked the original paper (Malenica et al., 2017) and the same values for Hb are reported (Table 2). I think there is a typing error in the original paper…

• Authors response: Thank you for raising this point. We have provided separate mean values for RBC, Hb, and HCT obtained for males and females in paragraph 2.3 to address the different normal reference ranges. Regarding the abnormal Hb values mentioned in lines 516-517, we have reviewed the data, and we also believe that this might be a typing error in the original paper. Such citation has been substituted.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

In their revised manuscript, the authors have adequately responded to the comments and suggestions made by the reviewer

Author Response

Dear Reviewer,

Thank you for your positive feedback. We appreciate your recognition of our efforts in addressing the comments and suggestions made.