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 needs.T 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

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©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% reduction 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). Fewer than half of the younger sub- Patients included in this study were individuals recruited from jects with emetropia were white (43%) compared with the practices of 6 medical centers (University of Alabama, Bir- 70% or more of the other 3 groups (PϽ.01). Females ac- mingham; University of California, San Francisco; Henry Ford counted for 79% of the older monovision group com- Hospital, Detroit, Mich; University of Texas Southwestern, pared with 56% of the older single-vision correction group Dallas; Naval Medical Center, San Diego, Calif; and University (PϽ.05). Hospitals of Cleveland, Cleveland, Ohio). At each institution the local institutional review board approved the enrollment of subjects. ASSOCIATION OF PRESBYOPIA Between June 1, 1999, and January 31, 2001, 38 subjects WITH THE NEI-RQL INSTRUMENT SCALES with ametropia (those with myopia and hyperopia) aged 45 years or older with monovision correction with contact lenses or by To assess the effect of presbyopia alone on vision- surgery; 486 subjects with myopia and hyperopia with sym- targeted quality of life, we compared the scores of younger

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Subjects With Emmetropia Subjects With Emmetropia Subjects With Monovision Subjects With Single-Vision Demographic Aged Ն45 y Aged Ͻ45 y Aged Ն45 y Correction Aged Ն45 y Characteristic (n = 38) (n = 75) (n = 38) (n = 486) Age, mean (range), y 54 (45-71) 32 (19-44) 55 (46-79) 56 (45-81) Female sex 63 68 79 56 Race White 71 43 84 75 African American 18 36 3 16 Asian 8 12 5 Hispanic 3 7 13 3 Other 3 1 Educational level High school diploma or less 32 15 13 15 Some college 24 49 45 29 Bachelor of arts degree 24 19 11 22 Postgraduate work 19 17 32 34 Annual income, $ Ͻ15 000 10 9 3 5 15 000-50 000 48 63 36 34 Ͼ50 000-100 000 26 22 36 37 Ͼ100 000 16 6 25 25 Work status (working full time) 71 87 74 67

*Data are given as percentage of subjects unless otherwise indicated.

(aged Ͻ45 years) subjects with emmetropia with those Table 2. Comparison of Older and Younger Subjects of older (aged Ն45 years) subjects with emmetropia not With Emmetropia* corrected with monovision. Table 2 presents the mean Age of Subjects With scores for each subscale by age group. The 38 subjects Emmetropia in the 45 years or older age group scored significantly worse (PϽ.05) on 7 of the 13 subscales (clarity of vi- NEI-RQL Younger sion, expectations, near vision, diurnal fluctuations, symp- Instrument Older (Ն45 y) (Ͻ45 y) t P toms, dependence on correction, and satisfaction with Subscale (n = 38) (n = 75) Value Value correction) compared with the 75 subjects in the younger Clarity of vision 86.90 (15.90) 93.32 (10.68) −2.24 .03 Ͻ age group. Comparison of mean scores among all sub- Expectations 53.95 (33.65) 90.54 (25.41) −5.90 .001 Near vision 81.52 (19.95) 95.89 (10.59) −4.15 Ͻ.001 jects, regardless of correction, in the age groups 50 years Far vision 89.61 (9.91) 91.95 (10.79) −1.12 .27 or younger, 51 to 60 years, and 61 years or older re- Diurnal fluctuation 76.86 (22.88) 87.44 (17.67) −2.71 .008 vealed that the scores of only 1 subscale (dependence on Activity limitation 93.97 (12.57) 96.59 (9.12) −1.14 .26 correction) worsened consistently with increasing age Glare 87.50 (18.61) 91.22 (17.40) −1.05 .30 (PϽ.001) (data not shown). Symptoms 78.95 (18.13) 86.15 (13.71) −2.15 .04 Dependence on 59.54 (27.17) 96.11 (14.17) −7.77 Ͻ.001 correction COMPARISON OF THE NEI-RQL INSTRUMENT Worry 73.36 (23.82) 77.36 (22.73) −0.87 .39 SCORES BETWEEN OLDER SUBJECTS Suboptimal 100.00 (0.00) 98.21 (7.76) 1.93 .06 WITH AMETROPIA WITH AND correction WITHOUT MONOVISION Appearance 81.98 (28.32) 88.97 (25.22) −1.31 .19 Satisfaction 82.11 (17.27) 93.14 (17.98) −3.09 .003 Table 3 presents the comparison of the mean scores Abbreviation: NEI-RQL, National Eye Institute Refractive Error Quality for the 13 subscales for 38 subjects aged 45 years or of Life. older corrected with monovision with the mean scores *Data are given as the mean (SD) scores unless otherwise indicated. of 486 participants aged 45 years or older with single- vision correction. Subjects with monovision correction scored statistically significantly higher then those sub- COMPARISON OF SUBJECTS WITH jects of similar age with single-vision correction on 3 of MONOVISION-CORRECTED PRESBYOPIA WITH the following NEI-RQL Instrument subscales: expecta- YOUNGER SUBJECTS WITH EMMETROPIA tions, dependence on correction, and appearance. These differences remained after adjustment for sex, race, edu- The NEI-RQL Instrument scores were significantly cational level, and annual income. Subjects with mono- worse for the 38 subjects with corrected monovision vision reported lower scores for clarity of vision (3 aged 45 years or older than for the 75 young subjects points), diurnal fluctuation (6 points), and glare (8 with nonmonovision emmetropia in all subscales points); however, the differences were not statistically except suboptimal correction and appearance as shown significant. in Table 4. Significant differences in mean scores

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©2003 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/29/2021 ranged from 49 for dependence on correction and 39 COMMENT for expectations to 6 or 7 for symptoms and activity limitation. Differences ranged between 9 and 23 for The NEI-RQL Instrument subscale scores indicate that the remaining subscales (clarity of vision, near vision, presbyopia is associated with substantial, negative ef- far vision, diurnal fluctuation, glare, worry, and fects on vision-targeted health-related quality of life. Mo- satisfaction). The magnitude of the difference is novision is one option for the correction of presbyopia reflected in the effect size (Table 4). Of the 11 subscales and can be achieved with contact lenses, keratorefrac- with statistically significant differences, 7 subscales tive surgery, or intraocular lenses in conjunction with showed large differences (clarity of vision, expectations, cataract extraction. Our data show that monovision is as- near vision, diurnal fluctuation, glare, dependence on sociated with a mix of positive and negative effects on correction, and satisfaction), 3 subscales showed differ- the health-related quality of life. Subjects with monovi- ences of medium magnitude (far vision, activity limita- sion have better expectations for their future vision, less tion, and worry), and 1 subscale showed a small dif- dependence on correction, and fewer problems with ap- ference (suboptimal correction).15 All differences pearance. These results have face validity, as these sub- remained statistically significant after adjustment for scales represent many of the concerns that subjects seek educational level, annual income, race, and sex. to address by pursuing monovision correction. The mean scores for the near and far vision subscales were not significantly different between the mo- Table 3. Comparison of Monovision and Single-Vision novision-corrected group and the single-vision correc- Forms of Correction in Subjects Aged 45 Years or Older tion group. The far vision subscale includes questions With Ametropia* about driving and other distance activities, suggesting that those with monovision correction were not limited in their NEI-RQL Subjects With Subjects With driving as a result of their correction. Instrument Monovision Single-Vision t P Subscale (n = 38) Correction (n = 486) Value Value Our study selected only subjects who had used their current form of vision correction for at least 3 months with- Clarity of vision 77.41 (18.10) 80.86 (19.38) −1.06 .29 out change. As a consequence, we selected for subjects who Expectations 51.97 (36.01) 37.86 (36.63) 2.29 .02 Near vision 80.48 (18.01) 77.20 (18.65) 1.05 .30 had undergone the adjustment to monovision and de- Far vision 82.85 (16.10) 80.16 (17.23) 0.93 .35 cided to continue with this form of correction. Also, we Diurnal fluctuation 66.34 (21.89) 71.94 (24.01) −1.39 .16 presumably selected for subjects without monovision who Activity limitation 89.53 (16.29) 85.83 (20.72) 1.07 .28 had either never tried monovision or tried it and failed to Glare 67.76 (32.31) 75.57 (26.90) −1.70 .09 adjust successfully to it, resulting in a return to single- Symptoms 79.91 (16.80) 79.40 (17.17) 0.18 .86 vision lenses. This self-selection is likely to be the expla- Dependence on 47.37 (35.49) 25.57 (28.41) 3.69 Ͻ.001 correction nation for the observed imbalances between groups in sex Worry 62.50 (26.95) 61.39 (25.68) 0.26 .80 and race distributions. Despite this self-selection and pre- Suboptimal 93.42 (15.03) 94.05 (16.91) −0.22 .82 sumed satisfaction of subjects with their current vision cor- correction rection, we were able to document some provocative dif- Appearance 87.98 (15.41) 79.15 (25.03) 3.18 .002 ferences in vision-targeted functioning and well-being. In Satisfaction 76.32 (17.92) 71.41 (23.29) 1.27 .21 future studies, the NEI-RQL Instrument should be administered to subjects prior to and after exposure to monovi- Abbreviation: NEI-RQL, National Eye Institute Refractive Error Quality of Life. sion correction to assess responsiveness of this instru- *Data are given as the mean (SD) scores unless otherwise indicated. ment to this change in correction.

Table 4. Comparison of Older Subjects With (Ն45 Years) Monovision vs Younger Subjects With (Ͻ45 Years) Emmetropia*

NEI-RQL Subjects With Monovision Younger Subjects With t P Instrument Subscale Aged Ն45 y (n = 38) Emetropia Aged Ͻ45 y (n = 75) Value Value ES† Clarity of vision 77.41 (18.10) 93.32 (10.68) −4.99 Ͻ.001 1.02 Expectations 51.97 (36.01) 90.54 (25.41) −5.89 Ͻ.001 1.12 Near vision 80.48 (18.01) 95.89 (10.59) −4.86 Ͻ.001 1.00 Far vision 82.85 (16.10) 91.95 (10.79) −3.14 .003 0.67 Diurnal fluctuation 66.34 (21.89) 87.44 (17.67) −5.51 Ͻ.001 0.98 Activity limitation 89.53 (16.29) 96.59 (9.12) −2.48 .017 0.57 Glare 67.76 (32.31) 91.22 (17.40) −4.17 .001 0.90 Symptoms 79.91 (16.80) 86.15 (13.71) −2.11 .04 0.41 Dependence on correction 47.37 (35.49) 96.11 (14.17) −8.14 Ͻ.001 1.48 Worry 62.50 (26.95) 77.36 (22.73) −3.07 .03 0.59 Suboptimal correction 93.42 (15.03) 98.21 (7.76) −1.84 .07 0.43 Appearance 87.89 (15.41) 88.97 (25.22) −0.27 .78 0.05 Satisfaction 76.32 (17.92) 93.14 (17.98) −4.65 Ͻ.001 0.86

Abbreviations: ES, effect size; NEI-RQL, National Eye Institute Refractive Error Quality of Life. *Data are given as the mean (SD) scores unless otherwise indicated. †The ES is a ratio of signal to noise calculated as numerator and denominator. The numerator is the difference and the denominator is the pooled SD. The boldfaced subscales and ESs indicated large ESs.

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©2003 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/29/2021 For many patients, contact lens fitting or surgery to limitations of monovision correction, multifocal intra- induce monovision can result in high levels of satisfac- ocular lenses, accommodating intraocular lenses, and tion, while other patients fail to adapt to this form of cor- other forms of correction of presbyopia with or without rection for a variety of reasons.4 Compared with full cor- myopia or hyperopia, and to patients seeking to under- rection of myopia or hyperopia to achieve maximal stand their options for correction of presbyopia. distance visual acuity in both eyes, which will result in dependence on corrective lenses for reading in most pa- Submitted for publication April 1, 2003; final revision re- tients older than 45 years, monovision seems to en- ceived June 9, 2003; accepted June 10, 2003. hance certain measures of vision-targeted health- This study was supported by contracts N01-EY6- related quality of life. Objective measurements of task 2112 (for the first 5 years of the contract) and N01- performance at near or distance (including landing jets) EY12113 (current contract) from the National Eye Insti- do not demonstrate significant decline of performance tute, National Institutes of Health, Bethesda, Md, with as a consequence of monovision.2,11 Whether there are additional support from the American Academy of Ophthal- some individuals or occupations for which monovision mology, San Francisco, Calif; Allergan Inc, Irvine; Bausch is at least relatively contraindicated cannot be deter- and Lomb–Contact Lens Division, Rochester, NY; Keravi- mined from our study. Although subjects with monovision Inc, Fremont, Calif; and the Visitec Company, Sara- sion reported lower scores for clarity of vision, diurnal sota, Fla. fluctuations, and glare, these differences were not sta- Corresponding author and reprints: Peter J. McDon- tistically significant. About 20% of individuals will not nell, MD, Wilmer Ophthalmological Institute, Maumenee tolerate a trial of monovision correction successfully1;it 727, 600 N Wolfe St, Baltimore, MD 21287 (e-mail: is usually possible to detect these individuals with a trial [email protected]). of soft lens wear for monovision. Our data make it clear that the highest scores are REFERENCES obtained with the NEI-RQL Instrument in young subjects with nonpresbyopic emmetropia. The significant dif- 1. Jain S, Arora I, Azar DT. Success of monovision in presbyopes: review of the ferences in mean scores between these subjects and those literature and potential applications to refractive surgery. Surv Ophthalmol. 1996; with monovision as the means of correction, most of 40:491-499. which are large, indicate that monovision correction does 2. Maguen E, Nesburn AB, Salz JJ. Bilateral photorefractive keratectomy with in- tentional unilateral undercorrection in an aircraft pilot. 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Report PB97-910403, NTSB/AAR-97/03, NYC97MA005. these subjects. 13. Hays RD, Lindblad A, Mangione C, et al. Psychometric properties of the National Eye Institute Refractive Error Quality of Life (NEI-RQL) Instrument. Ophthalmol- ogy. In press. CONCLUSION 14. Hays, RD, Anderson, RT, Revicki D. Assessing reliability and validity of mea- surement in clinical trials. In: Staquet M, Hays R, Fayers P, eds. Quality of Life Assessment in Clinical Trials: Methods and Practice. Oxford, England: Oxford The NEI-RQL Instrument may be helpful to clinicians University Press; 1998:169-182. and investigators seeking to understand the benefits and 15. Cohen J. A power primer. Psychol Bull. 1992;112:155-159.

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