Symptoms in Children with Intermittent Exotropia and Their Impact on Health-Related Quality of Life

Purpose: In childhood intermittent XT, the frequency and type of symptoms have not been rigorously studied. We aimed to identify specific symptoms in children with intermittent XT, their frequency, and effects on health-related quality of life (HRQOL). Methods: 35 children (5-13 years) with intermittent XT without previous surgery were enrolled in a prospective cohort study. Specific symptoms were identified from a previous study involving child and parent interviews and formulated as a 22-item symptom questionnaire. A frequency Likert-type rating scale was used and a response of "sometimes" or more was considered consistent with having the symptom. All 35 children, along with one parent for each child, also completed the patient-derived intermittent XT HRQOL questionnaire (IXTQ) with Child, Proxy, and Parent components. The frequency of symptoms was calculated, and the relationship between individual symptom question scores and Child, Proxy, and Parent HRQOL scores, was evaluated in multivariate linear regression analyses. Results: The mean number of specific symptoms was 7 (range 2 to 19). The most frequently reported were: rubbing the eye (29 [83%] of 35), problems with eyes in the sun, and the eyes feeling tired (each 22, 63%). Lower (worse) Child IXTQ HRQOL scores were associated with symptoms of difficulty focusing eyes (P=0.0007), double vision (P=0.007), eyes hurting (P=0.006), and problems with eyes in the sun (P=0.06). There were weak associations between Proxy IXTQ and Parent IXTQ scores and child symptoms. Overall, 7 symptom questions were associated with reduced HRQOL in multivariate models. Conclusion: Children with intermittent XT frequently experience symptoms, some of which impact the child's HRQOL. Formal assessment of symptoms may aid understanding of the effects of intermittent XT on an individual child, and could use just the 7 symptom questions associated with reduced HRQOL.