Cognitive dysfunction and depression in Fabry disease: a systematic review

Background Fabry disease, an X-linked lysosomal storage disorder, leads to multi-organ dysfunction, including cerebrovascular disease and psychological disorders. However, the prevalence and pattern of associated cognitive dysfunction is not well understood. Objectives To investigate whether there is reliable evidence for neuropsychological impairment in patients with Fabry disease and which cognitive domains are affected. To estimate the prevalence of and factors associated with depression in patients with Fabry disease. Method Qualitative systematic review of the literature of studies conducting neuropsychological assessment or measuring the prevalence of depression in adults with Fabry disease using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines where appropriate. Results There is some evidence for neuropsychological impairment in Fabry disease in executive functioning, information processing speed and attention, with preservation of: general intellectual functioning, memory, naming, perceptual functioning and global cognitive functioning. Prevalence rates of depression in Fabry disease ranged from 15 % to 62 %, with the largest study to date reporting a prevalence rate of 46 %. The most common factor associated with depression was neuropathic pain, both directly and indirectly by affecting social and adaptive functioning. Conclusion Our review suggests that Fabry disease may be associated with a characteristic pattern of cognitive deficits and a high prevalence of psychological disorders such as depression but highlights the limited available data. Exploring the nature of cognitive impairment in Fabry disease using standardised neuropsychological assessment, brain imaging and measures of depression is an important task for future research.