Abstract
Purpose:
We have previously reported that 95% of non-diplopic adult strabismus patients have subnormal health-related quality of life (HRQOL), particularly in the psychosocial domain. The present study evaluated whether there is a threshold of deviation magnitude below which psychosocial strabismus-specific HRQOL is largely unaffected.
Methods:
110 patients with non-diplopic strabismus completed the AS-20 questionnaire, a previously validated patient-derived instrument. Postoperative patients were included only if they were more than 1 year from surgery and had a residual deviation. Intermittent strabismus was excluded. Magnitude was defined as the largest of the simultaneous prism cover tests at distance or near fixation (or Krimsky when required). Multiple regression was used to assess whether magnitude and/or direction of deviation (eso, n=50, exo, n=52, hyper, n=8, hypo, n=6,) was predictive of HRQOL score within the Self-Perception and Interactions subscales of the AS-20. Spearman rank correlations, polynomial regression, and visual inspection of scatterplots were used to assess the relationship between magnitude and AS-20 score for each direction of deviation.
Results:
Overall regression analysis of magnitude and direction indicated that there were weak linear relationships between increasing magnitude of deviation and decreasing Self-Perception (r-sq=0.1992, p=0.0001) and Interaction (r-sq= 0.1425, p=0.001) subscale scores. Nevertheless, there was a great deal of individual variability, with small deviations sometimes associated with poor Self-Perception scores and poor Interaction scores. Overall, esotropia had less impact than exotropia. Polynomial regression did not improve the fit and there was no threshold under which HRQOL was largely unaffected. When considering esotropia and exotropia separately, Spearman rank correlations revealed a trend of reduced HRQOL with increasing deviation on both subscales (r= -0.28 to -0.39, p<0.05 for all), but individual variability was very high.
Conclusions:
Across a large cohort of strabismus patients there was an indication of decreasing HRQOL with increasing magnitude of deviation, but individual variability was marked and there was no threshold of deviation under which psychosocial scores were largely unaffected. Small-angle non-diplopic strabismus is often associated with poor psychosocial HRQOL.
Keywords: 722 strabismus •
669 quality of life •
515 esotropia and exotropia