Severity of diabetic retinopathy and health-related quality of life: the Los Angeles Latino Eye Study

Abstract

Objective: To assess the impact of diabetic retinopathy (DR) and its severity on health-related quality of life (HRQOL) in a population-based sample of Latinos with type 2 diabetes mellitus (DM).

Design: Cross-sectional population-based study, the Los Angeles Latino Eye Study (LALES).

Participants: We included 1064 LALES participants with DM.

Methods: We measured HRQOL by the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the Medical Outcomes Study 12-item Short Form Health Survey (SF-12). We assessed DR by masked standardized grading of stereoscopic photographs from 7 standard fields. Severity of DR in eyes was graded using a modified Airlie House classification. The severity scores from each eye were then concatenated to create a single per person grade ranging from 1 (no DR in either eye) to 15 (bilateral PDR). Multiple linear regression analyses were performed to determine the independent relationship between severity of DR and HRQOL after adjusting for covariates.

Main outcome measures: Scores on the NEI-VFQ-25 and SF-12.

Results: More severe DR was associated with worse HRQOL scores on all of the NEI-VFQ-25 and SF-12 subscales (P<0.05). Individuals with DR from grade 2 (minimum nonproliferative diabetic retinopathy [NPDR]) through grade 8 (unilateral moderate NPDR) show a modest decline in HRQOL. However, the decline becomes significantly steeper between steps 8 (unilateral moderate NPDR) and 9-15 (bilateral moderate NPDR to bilateral PDR). The domains with the most significant impact were for vision-related daily activities, dependency, and mental health.

Conclusions: Greater severity of DR was associated with lower general and vision-specific HRQOL. Persons with bilateral moderate NPDR had the most substantial decrease in quality of life compared with those with less severe DR. The prevention of incident DR and, more important, its progression from unilateral to bilateral NPDR is likely to have a positive impact on a person's HRQOL and should be considered an important goal in management of individuals with DM.

Figure 1

Relationship between National Eye Institute-Visual Function Questionnaire-25 (NEI-VFQ25) driving difficulty subscale and composite score and severity of diabetic retinopathy (DR) based on the concatenated scale with a locally weighted regression plot (LOWESS). Early Treatment Diabetic Retinopathy Study (ETDRS) scores correspond to the following clinical severity levels: No DR (levels 10 through 13; unilateral or bilateral nonproliferative DR (NPDR; levels 14 through 53); unilateral or bilateral proliferative DR (PDR; levels 60 through 85). DR Severity Concantenated scale step 9 (43/43) corresponds to bilateral moderate NPDR. The NEIVFQ25 scores have been adjusted for covariates.

Figure 2

Relationship between Short Form 12 (SF-12) physical and mental health component subscale scores and severity of diabetic retinopathy (DR) based on the concantenated scale with a locally weighted regression plot (LOWESS). Early Treatment Diabetic Retinopathy Study (ETDRS) scores correspond to the following clinical severity levels: No DR (levels 10 through 13; unilateral or bilateral nonproliferative DR (NPDR; levels 14 through 53); unilateral or bilateral proliferative DR (PDR; levels 60 through 85). DR Severity Concantenated scale step 9 (43/43) corresponds to bilateral moderate NPDR. The SF12 scores have been adjusted for covariates.