The Prevalence of Symptoms of Scotopic Sensitivity Syndrome/Meares-Irlen Syndrome in Subjects Diagnosed with Chronic Fatigue Syndrome

Several diagnostic symptoms of the visual-perception disorder scotopic sensitivity syndrome (SSS), also known as Meares-Irlen syndrome, are remarkably similar to the visual-symptom manifestations reported by individuals with chronic fatigue syndrome (CFS). Previous research has shown that the incidence of SSS comorbidity in subjects diagnosed with CFS is exceptionally high. We surveyed the incidences of nine widely-recognised symptoms of SSS in 20 subjects who had previously been diagnosed with CFS by a medical practitioner. The prevalence of each SSS symptom in the CFS group was compared to a group of age and sex-matched controls (n0 46), and also to a second group comprised of individuals (n018) diagnosed with the SSS disorder itself. The prevalence of SSS symptoms in the CFS-diagnosed group (frequency: 0.50 - 0.85; m00.62) was significantly higher than that of the control group (frequency: 0.02 - 0.26; m0.09). In contrast, our data revealed a remarkable lack of significant variations between the CFS-diagnosed and SSS-diagnosed groups. The degree of symptom overlap between the CFS and SSS disorders may thus be far stronger than previously reported and the preliminary evidence further suggests that individuals with SSS may be at increased risk of developing chronic fatigue syndrome.