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Associations of Presbyopia with Vision-Targeted Health-Related Quality of Life

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Associations of Presbyopia with Vision-Targeted Health-Related Quality of Life CLINICAL SCIENCES Associations of Presbyopia With Vision-Targeted Health-Related Quality of Life Peter J. McDonnell, MD; Paul Lee, MD, JD; Karen Spritzer; Anne S. Lindblad, PhD; Ron D. Hays, PhD Objective: To evaluate the associations of presbyopia in 7 of 13 subscales (PϽ.05). In those aged 45 years or and its correction, particularly monovision optical cor- older, correction of presbyopia with monovision was as- rection, with vision-targeted health-related quality of life. sociated with statistically significantly better scores on 3 subscales (expectations, dependence on correction, and Methods: The National Eye Institute Refractive Error appearance) compared with single-vision correction. One Quality of Life (NEI-RQL) Instrument was prospec- subscale (dependence on correction) showed worsen- tively self-administered by subjects from 6 medical cen- ing scores with increasing age without adjustment for need ters in the following age and correction categories: sub- or type of correction. Older persons with monovision cor- jects with emmetropia younger than 45 years (n=75), rection had significantly worse scores than younger sub- subjects with emmetropia aged 45 years or older (n=38), jects with emmetropia on all subscales except subopti- and subjects with ametropia aged 45 years or older with- mal correction and appearance. out monovision (n=486) or corrected with monovision (n=38). Differences in the 13 NEI-RQL Instrument sub- Conclusions: Presbyopia is associated with worse vision- scale scores among subjects in the 4 groups were exam- targeted health-related quality of life compared with ined. The age of 45 years or older was used as a surro- younger subjects with emmetropia. Monovision correc- gate for presbyopia. tion of presbyopia is related to some improvements in health-related quality of life, but it is still worse than that Results: A comparison of older (age Ն45 years) vs for younger subjects with emmetropia in several areas. younger (age Ͻ45 years) persons with emmetropia sug- gests that presbyopia was associated with reduced scores Arch Ophthalmol. 2003;121:1577-1581 HE FORM of optical correc- out needing to reach for reading glasses.1 tion chosen by a given in- As part of the surgical correction of re- dividual reflects his or her fractive error, monovision has been rec- lifestyle, including occupa- ommended for those patients who seek to From the Departments of tional and recreational minimize their future need for corrective Ophthalmology, University Tneeds. As such, patients active in sports lenses in any situation.2,3 of California, Irvine and outdoor activities that require excel- Not all patients are good candidates (Dr McDonnell), The lent distance visual acuity may desire op- for monovision, however, and not all will University of Southern timal distance correction, necessitating successfully adapt to it.4,5 The contact lens California, Los Angeles reading eyeglasses or bifocal contact lenses literature includes several studies of the (Dr McDonnell), and Duke University, Durham, NC for near vision if the patient is presby- likelihood of success with monovision. In (Dr Lee); Departments of opic. Presbyopia is believed to reflect a loss one review of published results on mono- 1 Medicine and Public Health, of accommodation due to stiffening of the vision, the mean success rate was 76% University of California, lens with age, a weakening of the ciliary (434 of 573 patients with successful mo- Los Angeles (Ms Spritzer muscle–lens zonule apparatus, or a com- novision); exclusion of contact lens– and Dr Hays); the EMMES bination of mechanisms. Subjects in the related intolerant individuals resulted in Corporation, Rockville, Md presbyopic age range of 45 years or older improvement in the success rate to 81%. (Dr Lindblad), and the RAND who read extensively for work and plea- Thus, a noteworthy percentage of pa- Corporation, Santa Monica, sure may value good uncorrected near vi- tients are not successfully corrected with Calif (Dr Hays). Dr McDonnell is now with the Wilmer sion above all else, and choose to be un- monovision. Ophthalmological Institute, dercorrected with their eyeglasses, contact Although many patients tolerate mo- Baltimore, Md. The authors lenses, or by surgery. Monovision is de- novision well, concerns exist regarding ad- have no relevant financial signed for presbyopic individuals who de- verse consequences of monovision, in- interest in this article. sire vision at both distance and near with- cluding difficulty in performing tasks that (REPRINTED) ARCH OPHTHALMOL / VOL 121, NOV 2003 WWW.ARCHOPHTHALMOL.COM 1577 ©2003 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/29/2021 require depth perception and good eye-hand coordina- metrical correction of vision with eyeglasses, contact lenses, or tion (eg, ball sports, surgical procedures, handling ma- by surgery in the age range of 45 years or older; 75 subjects with chinery, driving, and others). Monovision has been found emmetropia younger than 45 years; and 38 subjects with em- to produce either no change in binocular visual acuity metropia aged 45 years or older were recruited after signing an or a small to moderate change for both contact lens- institutional review board–approved consent statement. Age was 1,6 3 used as a surrogate for presbyopia. To be included in this study, induced or surgically created monovision. Contact lens– participants were required to be able to read English fluently as induced monovision reduces stereopsis; the magnitude a first or second language and to be able to complete a self- 7 of the reduction decreases with time. Monovision is re- administered questionnaire, the National Eye Institute Refrac- ported to cause no measurable change in peripheral vi- tive Error Quality of Life (NEI-RQL) Instrument.13 The partici- sual acuity or visual field width.8 Contrast sensitivity in- pants must have had a visual acuity of 20/32 or better (Ն75 letters) creases by the square root of 2 when the stimulus is viewed for near and far visual acuity in the worst eye with current cor- binocularly rather than monocularly. Thus, in the ab- rection, and they must have been using this current form and sence of monocular defocus the binocular contrast sen- magnitude of correction for at least 3 months. If the participant sitivity is about 42% greater than monocular contrast sen- had monovision, the eye corrected for near vision must have had sitivity. With increasing monocular defocus, the binocular a near visual acuity of 20/32 or better and the eye corrected for distance must have had a far visual acuity of 20/32 or better. Ex- contrast sensitivity decreases steadily and then falls be- clusionary criteria were as follows: chronic ocular disease or kera- low that of the monocular contrast sensitivity, showing toconjunctivitis sicca, diabetes mellitus, a neurological disease binocular inhibition. If the defocus is further increased that limits everyday activities, the inability to ascend a flight of (beyond a +2.5-diopter defocus), the binocular contrast stairs without assistance, and cognitive impairment (based on sensitivity reverts to the monocular sensitivity level, in- clinical judgment). dicating suppression of the defocused eye.9 Study findings of near task performance (such as card STATISTICAL METHODS filing and letter editing) demonstrate a 2% to 6% reduc- tion with contact lens-induced monovision.10 The suc- We used t tests to evaluate differences in mean scores on the 13 NEI-RQL Instrument subscales in 3 comparison groups of cess and safety of monovision correction in pilots re- Ն Ͻ 2 subjects; older (aged 45 years) vs younger (aged 45 years) mains a matter of controversy. Some authors claim subjects with emmetropia, older subjects with monovision vs success with monovision in pilot studies and 1 study re- older subjects with single-vision correction, and older sub- ports the excellent performance of military pilots ren- jects with monovision vs young subjects with emmetropia. In dered monocular.11 The opposite conclusion is offered the older subjects with monovision vs young subjects with em- by The National Transportation Safety Board’s investi- metropia groups, the magnitude of difference between groups gation of the October 19, 1996, Delta Airlines Flight 554 was evaluated using the effect size.14 This statistic, a ratio of nonfatal crash at La Guardia Airport, New York City, signal to noise, is calculated as the mean difference in scores which concluded that “the probable cause of this acci- between groups divided by the pooled standard deviation. Ac- 15 dent was the inability of the captain, because of his use cording to guidelines provided by Cohen, 0.2 represents a small of monovision contact lenses, to overcome his misper- difference, 0.5 a medium difference, and 0.8 a large difference. Analysis of variance was used to test for association of age with ception of the airplane’s position relative to the runway 12(pvii) the 13 subscale scores. Age groups in this analysis were de- during the visual portion of the approach.” fined as 50 years or younger, 51 to 60 years old, and 61 years The conflicting results and interpretations of spe- or older. Differences were considered statistically significant cialized vision testing in patients with monovision have at PՅ.05. All scores are given as the mean (SD). resulted in lingering uncertainty regarding the positive and negative aspects and the appropriate patient selec- RESULTS tion for this form of correction. This study represents the initial use of a survey to assess the effect of presbyopia Table 1 presents the distribution of the demographic on health-related quality of life and to compare mono- characteristics in the 4 groups of subjects. Work status vision, single-vision forms of optical correction, and sub- was balanced in the groups restricted to the ages of 45 jects with emmetropia. years or older. Several imbalances were observed. Older subjects with emetropia were more likely to have a high METHODS school diploma or less compared with the other 3 groups (32% vs Յ15%; PϽ.01) and to earn less than $50000 a ELIGIBILITY CRITERIA year compared with older subjects with ammetropia (58% vs 39%; PϽ.01).
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