Remaining visual field and preserved subjective visual functioning prevent mental distress in patients with visual field defects

Background: Patients with visual field defects after visual pathway lesion may experience reduced vision-related quality of life (vrQoL). It has not been clarified how vrQoL impairments contribute to vision-related mental distress.

Methods: One hundred and eight subjects with visual field defects caused by optic neuropathies (age M = 57.6; SD = 13.7 years) answered the National Eye Institute Visual-Functioning Questionnaire 39 (NEI-VFQ) for vrQoL and the SF-12 Short Form Health Survey for health-related quality of life. A 10 item composite of NEI-VFQ “visual functioning” and 5 items of “mental-health symptoms due to vision problems” were subjected to Rasch analysis. The test battery comprised static and High Resolution Perimetry (HRP). Regression and path analysis were used to investigate associations between QoL, mental distress, and perimetry results.

Results: A higher level of “visual functioning” was associated with monocular impairment and a larger remaining visual field compared to binocular impairment. Subjective “visual functioning” but not visual field parameters predicted “mental-health symptoms due to vision problems” which was the only variable associated with the SF-12 mental component score. The SF-12 physical component score was less strongly associated with “mental-health symptoms due to vision problems.” Here, reaction time in HRP and mean threshold in perimetry were additional significant variables. Path analysis revealed a significant path from remaining visual field via visual functioning on mental health.

Conclusion: Subjective consequences of visual impairments in everyday life impact mental health rather than “objective” visual function loss as measured by perimetry. Since a higher extent of vrQoL was related to lower levels of mental distress, the maintenance of vrQoL could reduce and prevent mental distress due to vision problems. Patients with persisting visual field defects may benefit from neuropsychological rehabilitation and supportive therapies.

Depression in the elderly with visual impairment and its association with quality of life

Background

Visual impairment is more prevalent in the elderly and depression is common in this population. Although many studies have investigated depression or quality of life (QOL) in older adults with visual impairment, few have looked at the association between these two concepts for this population. The aim of this systematized review was to describe the association between depression and QOL in older adults with visual impairment.

Methods

A search was done using multiple electronic databases for studies addressing the relationship between QOL and depression in elders with visual impairment. The concept of QOL was divided into two different approaches, ie, QOL as achievement and QOL as subjective well-being. Comparison of QOL scores between participants with and without depression (Cohen’s d) and correlations between depression and QOL (Pearson’s r) were examined.

Results

Thirteen studies reported in 18 articles were included in the review. Nearly all of the studies revealed that better QOL was moderately to strongly correlated with less severe depressive symptoms (r = 0.22–0.68 for QOL as achievement; r = 0.68 and 0.72 for QOL as subjective well-being). Effect sizes for the QOL differences between the groups with and without depression ranged from small to large (d = 0.17 to 0.95 for QOL as achievement; no data for QOL as subjective well-being).

Conclusion

Additional studies are necessary to pinpoint further the determinants and mediators of this relationship. Considering the high prevalence rate of depression in this community and its disabling effects on QOL, interventions to prevent and treat depression are essential. More efforts are needed in clinical settings to train health care practitioners to identify depressed elders with visual impairment and provide appropriate treatment.

Development and validation of the 21-item children's vision for living scale (CVLS) by Rasch analysis

BACKGROUND

The aim was to develop and validate an instrument called the 'Children's Vision for Living Scale' (CVLS) for the assessment of vision-related quality of life in Saudi Arabian children with and without amblyopia.

METHODS

A 43-item child self-report questionnaire was initially developed based on interviews with children with amblyopia, their parents and eye-care professionals, and a literature review. Following a process that involved the removal of redundant items, 28 items remained and were piloted on children aged five to 12 years with and without amblyopia (n = 48 amblyopic, n = 53 non-amblyopic) living in Saudi Arabia. Rasch analysis was applied to determine whether the 28-item questionnaire fitted the Rasch model. Rasch analysis was used to assess the validity and reliability of the questionnaire. Principal components analysis (PCA) was used to check dimensionality. A 21-item questionnaire resulting from this process was administered in children with (n = 81) and without (n = 82) amblyopia in Saudi Arabia for further validation.

RESULTS

The final 21-item questionnaire had good validity and reliability as demonstrated by person separation of 2.02, person reliability of 0.80 (mean square and standard deviation: infit = 1.01 ± 0.39; outfit = 1.01 ± 0.40) and item reliability of 0.93 (item infit range = 1.33 to 0.78; item outfit range = 0.78 to 1.30). The mean difference between person and item scores of 0.33 ± 0.53 logits (scale range, 2 to -2) indicates that the items are well targeted to the populations. The PCA (dimensionality measures) shows the percentage of variance explained by measures equal to 26.4 per cent (modelled 26.9 per cent) and an eigenvalue of the first contrast of 2.5, which demonstrated good stability.

CONCLUSION

The 21-item CVLS is a valid uni-dimensional child self-report instrument for the assessment of the impact of amblyopia on vision-related quality of life in children with and without amblyopia living in Saudi Arabia.

Visual outcome and impact on quality of life after surgeries differ in children operated for unilateral and bilateral cataract (Pune study 2011)

Background:

We compared vision and quality of life (VQL) of children aged 5-15 years and operated for unilateral and bilateral cataract between 2008 and 2010 in western India.

Materials and Methods:

In this cohort study, ophthalmologists assessed vision, anterior and posterior segment of eyes with cataract. Children completed a functional vision questionnaire (LVP-FVQ). Follow up at 6 months after surgery included the best corrected visual acuity (BCVA), FVQ and eye assessment. The improvement of BCVA and quality of life were compared in group of unilateral and bilateral cataract.

Result:

A total of 20 (70%) bilateral and 7 (39%) unilateral cataract were operated within 1 month of detection. All 48 eyes with bilateral cataract were congenital and 12 (67%) unilateral cataract were traumatic. Among bilateral group, 27 eyes [56.2% (95% confidence interval (CI) 44.4-72.2)] and in unilateral group 11 eyes [61.1% (95% CI 38.6-83.6)] had vision ≥ 20/60 at 6 months follow up. The visual gain was significantly higher in children who were operated between 1 month and 1 year of detection (adjusted Odds ratio (OR) = 15.6 P = 0.03). Positive impact on VQL in bilateral group was noted in 50%, 27%, and 13% children for subscale of distant vision, near vision, and field of vision, respectively. There was positive impact in these subscales among children with unilateral cataract. Thirty percent eyes with bilateral cataract and 22% of eyes with unilateral cataract improved their vision. Surgery within 1 month of cataract was significant predictor of improved vision (OR = 16.6 P = 0.02).

Conclusion:

Vision and VQL improved in children with unilateral and bilateral cataract. However, it was better 6 months following surgery in children with bilateral cataract than in children with unilateral cataract.

Re-evaluating a vision-related quality of life questionnaire with item response theory (IRT) and differential item functioning (DIF) analyses

BACKGROUND

For the Low Vision Quality Of Life questionnaire (LVQOL) it is unknown whether the psychometric properties are satisfactory when an item response theory (IRT) perspective is considered. This study evaluates some essential psychometric properties of the LVQOL questionnaire in an IRT model, and investigates differential item functioning (DIF).

METHODS

Cross-sectional data were used from an observational study among visually-impaired patients (n = 296). Calibration was performed for every dimension of the LVQOL in the graded response model. Item goodness-of-fit was assessed with the S-X(2)-test. DIF was assessed on relevant background variables (i.e. age, gender, visual acuity, eye condition, rehabilitation type and administration type) with likelihood-ratio tests for DIF. The magnitude of DIF was interpreted by assessing the largest difference in expected scores between subgroups. Measurement precision was assessed by presenting test information curves; reliability with the index of subject separation.

RESULTS

All items of the LVQOL dimensions fitted the model. There was significant DIF on several items. For two items the maximum difference between expected scores exceeded one point, and DIF was found on multiple relevant background variables. Item 1 'Vision in general' from the "Adjustment" dimension and item 24 'Using tools' from the "Reading and fine work" dimension were removed. Test information was highest for the "Reading and fine work" dimension. Indices for subject separation ranged from 0.83 to 0.94.

CONCLUSIONS

The items of the LVQOL showed satisfactory item fit to the graded response model; however, two items were removed because of DIF. The adapted LVQOL with 21 items is DIF-free and therefore seems highly appropriate for use in heterogeneous populations of visually impaired patients.