Purpose: To investigate symptom patterns and evaluate the relationship between patient characteristics and symptom severity before and after treatment for symptomatic children with convergence insufficiency (CI).
Methods: In a randomized clinical trial, the convergence insufficiency symptom survey was administered pre- and posttreatment to 221 children aged 9 to <18 years with symptomatic CI. Frequency of symptom type was determined at baseline, mean change in performance-related vs. eye-related symptoms for treatment responders was compared, and the relationship between patient characteristics and symptom severity at baseline for the entire cohort and after treatment for those who responded to treatment was determined.
Results: At baseline, the score for performance-related symptoms was greater than that for eye-related symptoms (mean response of 2.3 vs. 1.8, p < 0.001) regardless of age, sex, race/ethnicity, or presence of parent-reported Attention Deficit Hyperactivity Disorder (ADHD). Symptom severity increased with age for both the overall and eye-related subscale scores (p = 0.048, p = 0.022, respectively). Children with parent-reported ADHD were more symptomatic (p = 0.005) than those without parent-reported ADHD because of a higher performance-related score (p < 0.001). A significant and equal improvement (p < 0.01) for the performance- and eye-related symptoms was found in treatment responders. Girls had significantly lower performance-related symptoms than boys (p = 0.014), and black children reported less eye-related symptoms than white children (p = 0.022). Children without parent-reported ADHD had significantly less symptoms overall and less eye-related symptoms than children with parent-reported ADHD (p = 0.019, p = 0.011, respectively).
Conclusions: Because of a high frequency of both performance- and eye-related symptoms, clinicians should perform a targeted history that addresses both types of symptoms to help identify children with symptomatic CI. Future study regarding the relationship of CI and symptoms and their potential influence on ADHD, reading performance, and attention is warranted.
Trial registration: ClinicalTrials.gov NCT00338611.