The impact of change in visual field on health-related quality of life the los angeles latino eye study

Abstract

Purpose: To assess the impact of change in visual field (VF) on change in health-related quality of life (HRQoL) at the population level.

Design: Prospective cohort study.

Participants: Three thousand one hundred seventy-five Los Angles Latino Eye Study participants.

Methods: Objective measures of VF and visual acuity and self-reported HRQoL were collected at baseline and at the 4-year follow-up. Analysis of covariance was used to evaluate mean differences in change of HRQoL across severity levels of change in VF and to test for effect modification by covariates.

Main outcome measures: General and vision-specific HRQoL.

Results: Of 3175 participants, 1430 (45%) showed a change in VF (≥1 decibel [dB]) and 1715 (54%) reported a clinically important change (≥5 points) in vision-specific HRQoL. Progressive worsening and improvement in the VF were associated with increasing losses and gains in vision-specific HRQoL for the composite score and 10 of its 11 subscales (all P(trend)<0.05). Losses in VF of more than 5 dB and gains of more than 3 dB were associated with clinically meaningful losses and gains in vision-specific HRQoL, respectively. Areas of vision-specific HRQoL most affected by greater losses in VF were driving, dependency, role-functioning, and mental health. The effect of change in VF (loss or gain) on mean change in vision-specific HRQoL varied by level of baseline vision loss (in VF, visual acuity, or both) and by change in visual acuity (all P(interaction)<0.05). Those with moderate or severe VF loss at baseline and with a more than 5 dB loss in VF during the study period had a mean loss of vision-specific HRQoL of 11.3 points, whereas those with no VF loss at baseline had a mean loss of 0.97 points. Similarly, with a more than 5 dB loss in VF and baseline visual acuity impairment (mild or severe), there was a loss in vision-specific HRQoL of 10.5 points, whereas with no visual acuity impairment at baseline, there was a loss of vision-specific HRQoL of 3.7 points.

Conclusions: Both losses and gains in VF produce clinically meaningful changes in vision-specific HRQoL. In the presence of pre-existing vision loss (VF and visual acuity), similar levels of VF change produce greater losses in QOL.

Figure 1

Locally weighted, least squares plot (LOWESS) depicting the relationship between change in visual field (mean deviation in decibels) and predicted change in vision-specific health related quality of life (HRQoL) in the better and worse seeing eye. Vision-specific HRQoL was measured using the National Eye Institute Visual Function Questionnaire-25 composite score (CS).

Figure 2

Proportion of individuals with a ≥ 5 point change in vision-specific health related quality of life (HRQoL) composite score (CS) across decreasing levels of change in visual field (mean deviation in decibel). Vision-specific HRQoL was measured using the National Eye Institute Visual Function Questionnaire-25 CS. A five-point change in vision-specific HRQoL was considered a minimal clinically important difference.

Figure 3

LOWESS plots depicting the relationship between change in vision-specific health related quality of life (HRQoL) across levels of mean change in visual field [Mean deviation (MD) expressed in decibels (dB)], by severity of impairment in baseline visual acuity (VAI). The figure shows that the effect of change in visual field on vision-specific HRQoL varies by levels of VAI (mild to severe vs. none). The crossing of lines suggests interaction between change in visual field and VAI on their effect in producing a change in vision-specific HRQoL. The intersection of the two broken lines (----) represents the point where there is no change in visual field and no change in vision-specific quality of life.