Impact of vision loss on health-related quality of life in Trinidad and Tobago

Purpose: To determine whether distance vision impairment (VI) (Logarithm of the Minimum Angle of Resolution (LogMAR) >0.30), or near VI (NVI) (LogMAR 0.32 to 1.30 at 40cm with <0.30 at 3m) independently predict health-related quality of life (HRQoL), and to estimate societal impact. Design: The National Eye Survey of Trinidad and Tobago was a population-based, cross-sectional eye survey using multi-stage, cluster random sampling with probability-proportionate-to-size methods. Participants: Adults aged > 40 years. Methods: Responders rated general health level in the five dimensions (mobility, self-care, usual activities, pain/discomfort and anxiety/depression) of the EQ-5D 5-level instrument. Multivariable regression analysis with robust standard error estimation explored the relationship between utility score and presenting vision. Main Outcome Measures: Utility value and Quality Adjusted Life Year (QALY) loss by vision category. Results: 62.4% (2658/4263) adults completed the EQ-5D-5L. Mean age was 58.4 (SD 11.8, range 40 to 103) years and 56.3% were female. Blindness had the largest independent effect on utility coefficient, at -0.140 (95% CI -0.092 to -0.192), with mean utility value 0.727 (95% CI 0.671-0.784) and mean EQ-VAS score 69.9 (95% CI 62.0-77.8). Near VI was also independently associated with utility loss of -0.012 (95% CI -0.004 to -0.021). Independent predictors of utility<1.000 included female sex, older age, being uninsured, lower educational attainment, ethnicity, and multiple medical co-morbidities. A hypothetical person, experiencing onset of a stable vision state at 40 years, would be expected to accrue lifetime loss of 0.45 QALYs for near VI, 0.72 QALYs for mild VI, 1.64 QALYs for moderate VI, 3.30 QALYs for severe VI and 5.13 QALYs for blindness. VI caused 762.3 QALYs lost per 100,000 population per year, of which 36.5% were attributed to near VI, exceeding the equivalent QALY loss from stroke (307 QALYs), depression (284 QALYs), and arthritis (522 QALYs). 91% (694.9/762.3) of the VI-related QALY loss was potentially avoidable. Conclusions: This is the first population-based survey to identify that both distance and near VI independently reduce HRQoL. The estimated QALY loss highlights the societal importance of efforts to address all degrees of avoidable VI.