Indian Journal of Health Sciences and Biomedical Research KLEU

LETTER TO THE EDITOR
Year
: 2022  |  Volume : 15  |  Issue : 2  |  Page : 186-

Comment on “correlation between cigarette smoking and raised intraocular pressure in males”


Jasmita Satapathy 
 Department of Ophthalmology, IMS and SUM Hospital, Bhubaneswar, Odisha, India

Correspondence Address:
Dr Jasmita Satapathy
Department of Ophthalmology, IMS and SUM Hospital, Bhubaneswar - 751 003, Odisha
India




How to cite this article:
Satapathy J. Comment on “correlation between cigarette smoking and raised intraocular pressure in males”.Indian J Health Sci Biomed Res 2022;15:186-186


How to cite this URL:
Satapathy J. Comment on “correlation between cigarette smoking and raised intraocular pressure in males”. Indian J Health Sci Biomed Res [serial online] 2022 [cited 2022 Aug 13 ];15:186-186
Available from: https://www.ijournalhs.org/text.asp?2022/15/2/186/345822


Full Text



Dear Editor,

It was interesting reading the article entitled, “Correlation between cigarette smoking and raised intraocular pressure (IOP) in males.”[1] I congratulate the authors for the important analysis. However, I have few important observations and suggestions to make regarding the study design.

Firstly, to find the correlation between smoking and IOP, it would have been better to divide the groups as smokers (Group A) and nonsmokers (Group B) and then comparing mean IOP between two groups. However, the authors have made two groups as Group A (those with raised IOP irrespective of visual field defect and optic neuropathy) and Group B (those with normal IOP and without any ocular signs and symptoms). By doing so, it could so happen that you might not get a good number of patients with history of smoking in either group or in Group A, which in turn might interfere in proper data analysis.

Second, potential confounders need to be dealt with during study design as they can lead to erroneous conclusions.[2] Confounding variables are those that may compete with the exposure of interest in explaining the outcome of a study.[2] Hypertension is a true confounder here which is predictive of the outcome (raised IOP) even in the absence of the exposure (cigarette smoking). It would have been better if hypertension is included in exclusion criteria. Although it is possible to have residual confounding by the factors that are unknown and cannot be measured, the true confounders have to be taken care of to avoid bias.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Mukherji S, Karmakar S, Dasgupta S. Correlation between cigarette smoking and raised intraocular pressure in males. Indian J Health Sci Biomed Res 2021;14:245-8.
2Skelly AC, Dettori JR, Brodt ED. Assessing bias: The importance of considering confounding. Evid Based Spine Care J 2012;3:9-12.