Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers

Masayuki Tatemichi; Tadashi Nakano; Katsutoshi Tanaka; Takeshi Hayashi; Takeshi Nawa; Toshiaki Miyamoto; Hisanori Hiro; Minoru Sugita

doi:10.1136/jech.2003.018127

Responses

Research report

Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers

Compose a Response to This Article

Compose Response

Title *

Author Information

Contributors
First Name and Middle Initial * First or given name, e.g. 'Peter'. Last Name * Your last, or family, name, e.g. 'MacMoody'. Email Address * Your email address, e.g. higgs-boson@gmail.com Occupation * Your role and/or occupation, e.g. 'Orthopedic Surgeon'. Affiliation * Your organization or institution (if applicable), e.g. 'Royal Free Hospital'.

Statement of Competing Interests

Competing interests? *

Yes

Please describe the competing interests

PLEASE NOTE:

A rapid response is a moderated but not peer reviewed online response to a published article in a BMJ journal; it will not receive a DOI and will not be indexed unless it is also republished as a Letter, Correspondence or as other content. Find out more about rapid responses.
We intend to post all responses which are approved by the Editor, within 14 days (BMJ Journals) or 24 hours (The BMJ), however timeframes cannot be guaranteed. Responses must comply with our requirements and should contribute substantially to the topic, but it is at our absolute discretion whether we publish a response, and we reserve the right to edit or remove responses before and after publication and also republish some or all in other BMJ publications, including third party local editions in other countries and languages
Our requirements are stated in our rapid response terms and conditions and must be read. These include ensuring that: i) you do not include any illustrative content including tables and graphs, ii) you do not include any information that includes specifics about any patients,iii) you do not include any original data, unless it has already been published in a peer reviewed journal and you have included a reference, iv) your response is lawful, not defamatory, original and accurate, v) you declare any competing interests, vi) you understand that your name and other personal details set out in our rapid response terms and conditions will be published with any responses we publish and vii) you understand that once a response is published, we may continue to publish your response and/or edit or remove it in the future.
By submitting this rapid response you are agreeing to our terms and conditions for rapid responses and understand that your personal data will be processed in accordance with those terms and our privacy notice.

I agree to and have read the terms and conditions for rapid responses and BMJ Privacy Notice *

CAPTCHA

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Vertical Tabs

Other responses

Jump to comment:

Glaucoma from PC usage
Michael -
Published on: 27 April 2016
Re: The incidence of glaucoma in Japanese workers is comparable to a white population
Pradeep G Paul
Published on: 27 April 2016
Computers and glaucoma
John Mulock-Houwer
Published on: 27 April 2016
Author's reply
Masayuki Tatemichi
Published on: 27 April 2016
The incidence of glaucoma in Japanese workers is comparable to a white population
Pieter Gouws
Published on: 27 April 2016

Published on: 27 April 2016
Glaucoma from PC usage
- Michael -, Video Editor
Dear Editor
As a PC user this article interests me greatly, as I have noticed my eyesight deteriorating since working 11 hour a day shifts in front of 4 monitors and sometimes also using the computer again after work at home.
From a lay man's perspective I would like to know more about how different types of screen affect the eyes, and indeed whether the problem may stem simply from levels of artificial...
Show More

Dear Editor
As a PC user this article interests me greatly, as I have noticed my eyesight deteriorating since working 11 hour a day shifts in front of 4 monitors and sometimes also using the computer again after work at home.
From a lay man's perspective I would like to know more about how different types of screen affect the eyes, and indeed whether the problem may stem simply from levels of artificial light (which are greater when staring at a monitor). Often the combination of artificial light levels from room/office lights as well as the computer screens themselves contribute to a worsening state of vision in my own eyes. This could be tiredness of the eyes in addition to the above, however in natural daylight the same cannot be said, except perhaps if using a computer screen out of doors under sunlight (this I have not tried).
Anyway, any further study or pointers to further study would be much appreciated as I worry that the correlation here combined with my own experience may mean that I should change my lifestyle in order to avoid glaucoma or blindness in later life. I am currently already nearsighted +1.25.
Thanks Michael
Show Less

Conflict of Interest:
None declared.
- Back to top
Published on: 27 April 2016
Re: The incidence of glaucoma in Japanese workers is comparable to a white population
- Pradeep G Paul, Epidemiologist
- Other Contributors:
  21 Pycrofts Garden Road, Nungambakkam, Chennai - 600006.
Dear Editor,
This is in response to the response letter from Pieter Gouws, Ophthalmologist Glaucoma Fellow, Toronto Western Hospital, Toronto, Canada. "The incidence of glaucoma in Japanese workers is comparable to a white population" for the manuscript "Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers."
Pieter i...
Show More

Dear Editor,
This is in response to the response letter from Pieter Gouws, Ophthalmologist Glaucoma Fellow, Toronto Western Hospital, Toronto, Canada. "The incidence of glaucoma in Japanese workers is comparable to a white population" for the manuscript "Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers."
Pieter in his letter had stated that the incidence of glaucoma in Japanese workers is comparable to a white population. I doubt if Pieter has mispelt incidence, since Glaucoma is a chronic irreversible condition, prevalence will make more sense rather than incidence. I understand that Pieter is trying to compare the frequency across the two population, in order to be clear to the reader I suggest Pieter's statement would sound better if stated like this "The Prevalence of glaucoma among Japanese workers are comparable to a white population". This is just another incidence where 'prevalence' and 'incidence' are often used inappropriately.
Thank you
Pradeep.
Reference
1. Friedman GD.Medical usage and abusage: "prevalence" and "incidence". Ann Intern Med. 1976 Apr;84(4):502-4.
Show Less

Conflict of Interest:
None declared.
- Back to top
Published on: 27 April 2016
Computers and glaucoma
- John Mulock-Houwer, Retired Engineer
Dear Editor
As my father, A W Mulock Houwer, was a professor of ophtalmology, I have always been interested in engineering associated with medical (particularly eye) afflictions. Therefore I would like to ask if there was any reference to the type of display used with the computers in Tatemichi et als study.[1] I realise that liquid crystal displays and plasma displays have only been in use for a short perio...
Show More

Dear Editor
As my father, A W Mulock Houwer, was a professor of ophtalmology, I have always been interested in engineering associated with medical (particularly eye) afflictions. Therefore I would like to ask if there was any reference to the type of display used with the computers in Tatemichi et als study.[1] I realise that liquid crystal displays and plasma displays have only been in use for a short period of time, but it has already been seized on by unscrupulous dealers, who tell computer users that it is very important that they change over to the dearer flat screen displays to safeguard their eyesight. With my limited medical training it is difficult to evaluate whether the glaucoma threat is due to any radiation from the computer screen, or from the constant distance of focus for the operator. In the last case it would, of course, be immaterial what type of screen was in use.
References
1. Tatemichi M, Nakano T, Tanaka K, Hayashi T, Nawa T, Miyamoto T, Hiro H, Sugita M. Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers. J Epidemiol Community Health 2004; 58: 1021-1027.
Show Less

Conflict of Interest:
None declared.
- Back to top
Published on: 27 April 2016
Author's reply
- Masayuki Tatemichi
Dear Editor
Ever since the publication of our study,[1] we have been overwhelmed with literally hundreds of inquiries, mostly on the safety of PCs in visual health. As Gouws pointed out correctly, many were misled after heavy coverage by lay media to think we had proven the harmful effect of PC use on the eyes.[2]
In retrospect, we realise the importance of using a very clear language in the manuscript...
Show More

Dear Editor
Ever since the publication of our study,[1] we have been overwhelmed with literally hundreds of inquiries, mostly on the safety of PCs in visual health. As Gouws pointed out correctly, many were misled after heavy coverage by lay media to think we had proven the harmful effect of PC use on the eyes.[2]
In retrospect, we realise the importance of using a very clear language in the manuscript, making it understandable to those without a solid background in epidemiology. We wrongfully assumed that no one would misinterpret the cross-sectional findings as the proof of causation. We would like to take this opportunity to clarify our position.
* What we found: a positive association between the heavy PC users and visual field abnormalities, only among those with refractive errors. Similar association was not seen among those without refractive errors.
*We do not know whether: heavy PC use will cause or hasten the development of glaucoma, as the study we ran was not designed to test the cause-effect relationship; heavy PC use will heighten the risk of glaucoma through worsening of myopia, a known risk factor for glaucoma, as our study was not designed to test this hypothesis.
Many questioned whether our findings were unique to Japanese ethnicity who have somewhat different prevalence of glaucoma subtypes. We are tempted to address various possibilities about the potential of sampling bias, but only by speculation, without any evidence in our hands.
Since our study was hypothesis generating in nature, rather than hypothesis testing, we now need to ask many more questions in order to promote the better visual health among PC users. We would like to invite all interested parties to join force and investigate this issue.
References
1. Tatemichi M, Nakano T, Tanaka K, Hayashi T, Nawa T, Miyamoto T, Hiro H, Sugita M. Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers. J Epidemiol Community Health 2004; 58: 1021-1027.
2. Gouws P. The incidence of glaucoma in Japanese workers is comparable to a white population [electronic response to Tatemichi M, Nakano T, Tanaka K, Hayashi T, Nawa T, Miyamoto T, Hiro H, Sugita M. Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers] jech.com 2004 URL direct link to eLetter
Show Less

Conflict of Interest:
None declared.
- Back to top
Published on: 27 April 2016
The incidence of glaucoma in Japanese workers is comparable to a white population
- Pieter Gouws, Ophthalmologist
Dear Editor
I congratulate the Tatemichi et al on an interesting study.[1] However, as this paper has been widely sited in the general press, I would like to point out that this study does not show that heavy computer use causes glaucoma as suggested by the international press agencies.
The prevalence of open angle glaucoma is well known from various epidemiological studies and ranges from 1-3% in...
Show More

Dear Editor
I congratulate the Tatemichi et al on an interesting study.[1] However, as this paper has been widely sited in the general press, I would like to point out that this study does not show that heavy computer use causes glaucoma as suggested by the international press agencies.
The prevalence of open angle glaucoma is well known from various epidemiological studies and ranges from 1-3% in white populations to 10% in African Americans and up to 15% in African Caribbeans.[2-12]
In this cohort of 9124 (8602+522) Japanese workers, only 315 of workers with abnormal visual fields consented to ophthalmological examination and 210 (66.67%) of those were felt to have suspect glaucomatous discs. If this percentage were to be taken as the same for the 207 workers excluded, that would give a total of 348 (210 + 138). This would give an incidence of glaucoma of 3.8% in this group of workers!
Even if the entire excluded group were taken as positive, this still gives an incidence of glaucoma of 4.6% (210+207/9124 x %) for this group. In addition, this study shows that not all the workers with suspect glaucomatous optic discs had glaucoma suggesting an incidence of glaucoma in this population of approximately 3%, which corresponds to the incidence in a general white population! Furthermore, myopia is thought to be a significant risk factor for the development of glaucoma[13-15] and 96.4% of the “glaucoma” group in this study were found to have a myopic prescription.
References
1. Tatemichi M, Nakano T, Tanaka K, Hayashi T, Nawa T, Miyamoto T, Hiro H, Sugita M. Possible association between heavy computer users and glaucomatous visual field abnormalities: a cross sectional study in Japanese workers. J Epidemiol Community Health 2004; 58: 1021-1027
2. Kahn HA, Milton RC. Alternative definitions of open-angle glaucoma: effect on prevalence and associations in the Framingham Eye Study. Arch Ophthalmol. 1980;98:2172-2177.
3. Bengtsson B. The prevalence of glaucoma. Br J Ophthalmol. 1981;65:46-49.
4. Tielsch JM, Sommer A, Katz J, Royall RM, Quigley HA, Javitt J. Racial variations in the prevalence of primary open-angle glaucoma: the Baltimore Eye Survey. JAMA. 1991;266:369-374.
5. Ringvold A, Blika S, Elsas T, et al. The Middle-Norway eye- screening study, II: prevalence of simple and capsular glaucoma. Acta Ophthalmol (Copenh). 1991;69:273-280
6. Klein B, Klein R, Sponsel WE, et al. Prevalence of glaucoma: the Beaver Dam Eye Study. Ophthalmology. 1992;99:1499-1504.
7. Dielemans I, Vingerling JR, Wolfs RCW, Hofman A, Grobbee DE, de Jong PT. The prevalence of primary open-angle glaucoma in a population- based study in the Netherlands. Ophthalmology. 1994;101:1851-1855.
8. Leske MC, Connell AMS, Schachat AP, Hyman L for the Barbados Eye Study Group. The Barbados Eye Study: prevalence of open-angle glaucoma. Arch Ophthalmol. 1994;112:821-829
9. Mitchell P, Smith W, Attebo K, Healey PR. Prevalence of open-angle glaucoma in Australia: the Blue Mountains Eye Study. Ophthalmology. 1996;103:1661-1669.
10. Leske MC, Ederer F, Podgor M. Estimating incidence from age- specific prevalence in glaucoma. Am J Epidemiol. 1981;113:606-613
11. Podgor MJ, Leske MC, Ederer F. Incidence estimates for lens changes, macular changes, open-angle glaucoma, and diabetic retinopathy. Am J Epidemiol. 1983;118:206-212
12. Quigley HA, Vitale S. Models of open-angle glaucoma prevalence and incidence in the United States. Invest Ophthalmol Vis Sci. 1997;38:83- 91.
13. Ponte F, Giuffre G, Giammanco R, Dardononi G. Risk factors of ocular hypertension and glaucoma: the Casteldaccia Eye Study. Doc Ophthalmol. 1994;85:203-210.
14. Mitchell P, Hourihan F, Sandbach J, Wang JJ. The relationship between glaucoma and myopia: the Blue Mountains Eye Study. Ophthalmology. 1999;106:2010-2015.
15. Perkins ES, Phelps CD. Open angle glaucoma, ocular hypertension, low-tension glaucoma, and refraction. Arch Ophthalmol. 1982;100:1464-1467
Show Less

Conflict of Interest:
None declared.
- Back to top

Main menu

Plain text

PLEASE NOTE:

Vertical Tabs

Other responses

Jump to comment:

Log in using your username and password

Main menu

Log in using your username and password

You are here

Plain text

PLEASE NOTE:

Vertical Tabs

Other responses

Jump to comment:

Read the full text or download the PDF:

Log in using your username and password