Purpose:
To investigate the prevalence of and risk factors for depression among participants with glaucoma and the predictive value of glaucoma for depression.
Methods:
This cross-sectional study included 6760 participants in the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2008, age ≥40 years, who reported a presence or absence of glaucoma. Demographic as well as health- and disease-related information was obtained by interview. Self-reported measures of vision and visual disability were ascertained via items from the Visual Function Questionnaire (VFQ-25). Participants underwent visual acuity examination, fundus photography, and visual field testing with screening frequency doubling technology (FDT N-30-5). The main outcome was presence of depression, as determined by a score ≥10 on the Patient Health Questionnaire-9 (PHQ-9).
Results:
Prevalence of depression among participants with and without glaucoma was 10.9% (SEM 2.2%) and 6.9% (SEM 0.62%), respectively. While the presence of glaucoma was significantly associated with depression after adjustment for demographic factors (OR 1.80, 95% CI 1.16 - 2.79), this association was not significant after adjustment for self-reported general health condition (OR 1.35, 95% CI 0.822-2.23). Objective measures of glaucoma severity were not found to be significant predictors for depression. However, self-reported measures of visual function including difficulty seeing despite glasses or contacts (P=0.008), time spent worrying about eyesight (P=.0053) and visual limitations impacting time spent on activities (P=0.0009) were significantly associated with depression.
Conclusions:
Glaucoma was not a significant predictor of depression after adjustment for general health condition. Among participants with glaucoma, self-reported measures of vision and visual disability were significant risk factors for depression, whereas objective measures of vision and glaucoma severity were not. Our study suggests that the impact of glaucoma on mental health is mediated by patients’ perceptions and subjective experiences of their illness rather than by conventional measures of glaucoma severity.
Keywords: clinical (human) or epidemiologic studies: risk factor assessment • quality of life