Abstract
Purpose: :
Over the last 15 years, a number of studies have suggested that visually impaired people may have a concomitant problem of sleep disturbance. Our own research has indicated the 50% of patients with Retinitis Pigmentosa (RP) and Stargardt’s Disease (SD) experience notable sleep disturbance (ARVO 2010, 2011). This study extends the range of diagnoses to include Age-related Macular Degeneration (AMD) and delves into more specific and subjective elements of sleep behavior and difficulties.
Methods: :
Patients with a diagnosis of RP (n=82), SD (n=13) and AMD (n=51) participated in this study. They were interviewed in-person or over the phone using three questionnaires; the Pittsburg Sleep Quality Index (PSQI), the Epworth Sleepiness Scale and the Brief General Health Assessment. The PSQI assessed 7 components of sleep: latency, duration, subjective quality, efficiency, disturbances, use of sleep medication and daytime dysfunction. The Epworth Sleepiness Scale was used to evaluate sleepiness during the day and the Brief General Health Assessment served to exclude patients with other disorders that may cause poor quality of sleep.
Results: :
As had previously been reported for patients with RP and SD, 50% of the patients with AMD had an overall score on the PSQI that indicated the presence of sleep disturbance. In terms of the 7 subscales of the PSQI, there was no significant difference in sleep latency, duration or daytime dysfunction among the three groups. Scores reflecting sleep quality showed that AMD patients are the best sleepers and RP patients are the worst, F(2,161) = 7.04, p<.01. RP patients also experience the most sleep disturbances while AMD patients suffer the least, F(2,161) = 6.22, p<.01. Habitual sleep efficiency was found to differ significantly among the three groups with RP being the most efficient and AMD being the least, F(2,161) = 3.58, p<.05. Stargardt’s patients were found to have the least sleep disturbances and used the least amount of sleep-related medication, F(2,161) = 5.52, p<.01. The Epworth Sleepiness Scale revealed that RP patients experienced the most daytime sleepiness while those with AMD felt least sleepy during the day.
Conclusions: :
These results suggest that sleep disturbances and habitual sleep efficiency have an influencing role on the poor overall sleep quality of over 50% of patients with retinal dystrophies and AMD. Eye-care and rehabilitation specialists should be aware of the high prevalence of poor sleep quality in patients with retinal disorders since this situation may have an important impact on communication issues such as alertness, comprehension and recall.
Keywords: low vision • quality of life