|LETTER TO THE EDITOR
|Year : 2022 | Volume
| Issue : 2 | Page : 186
Comment on “correlation between cigarette smoking and raised intraocular pressure in males”
Department of Ophthalmology, IMS and SUM Hospital, Bhubaneswar, Odisha, India
|Date of Submission||08-Jun-2021|
|Date of Acceptance||08-Feb-2022|
|Date of Web Publication||24-May-2022|
Dr Jasmita Satapathy
Department of Ophthalmology, IMS and SUM Hospital, Bhubaneswar - 751 003, Odisha
Source of Support: None, Conflict of Interest: None
|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
It was interesting reading the article entitled, “Correlation between cigarette smoking and raised intraocular pressure (IOP) in males.” 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. Confounding variables are those that may compete with the exposure of interest in explaining the outcome of a study. 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
Conflicts of interest
There are no conflicts of interest.
| References|| |
Mukherji 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. [Full text]
Skelly AC, Dettori JR, Brodt ED. Assessing bias: The importance of considering confounding. Evid Based Spine Care J 2012;3:9-12.