Psychiatric and cognitive profile in Anderson-Fabry patients: a preliminary study

Consensus recommendations for the treatment and management of patients with Fabry disease on migalastat: a modified Delphi study

Objective

Fabry disease is a progressive disorder caused by deficiency of the α-galactosidase A enzyme (α-Gal A), leading to multisystemic organ damage with heterogenous clinical presentation. The addition of the oral chaperone therapy migalastat to the available treatment options for Fabry disease is not yet universally reflected in all treatment guidelines. These consensus recommendations are intended to provide guidance for the treatment and monitoring of patients with Fabry disease receiving migalastat.

Methods

A modified Delphi process was conducted to determine consensus on treatment decisions and monitoring of patients with Fabry disease receiving migalastat. The multidisciplinary panel comprised 14 expert physicians across nine specialties and two patients with Fabry disease. Two rounds of Delphi surveys were completed and recommendations on the use of biomarkers, multidisciplinary monitoring, and treatment decisions were generated based on statements that reached consensus.

Results

The expert panel reached consensus agreement on 49 of 54 statements, including 16 that reached consensus in round 1. Statements that reached consensus agreement are summarized in recommendations for migalastat treatment and monitoring, including baseline and follow-up assessments and frequency. All patients with Fabry disease and an amenable mutation may initiate migalastat treatment if they have evidence of Fabry-related symptoms and/or organ involvement. Treatment decisions should include holistic assessment of the patient, considering clinical symptoms and organ involvement as well as patient-reported outcomes and patient preference. The reliability of α-Gal A and globotriaosylsphingosine as pharmacodynamic response biomarkers remains unclear.

Conclusion

These recommendations build on previously published guidelines to highlight the importance of holistic, multidisciplinary monitoring for patients with Fabry disease receiving migalastat, in addition to shared decision-making regarding treatments and monitoring throughout the patient journey. GRAPHICAL ABSTRACT.

Fabry Disease and Central Nervous System Involvement: From Big to Small, from Brain to Synapse

Fabry disease (FD) is an X-linked lysosomal storage disorder (LSD) secondary to mutations in the GLA gene that causes dysfunctional activity of lysosomal hydrolase α-galactosidase A and results in the accumulation of globotriaosylceramide (Gb3) and globotriaosylsphingosine (lyso-Gb3). The endothelial accumulation of these substrates results in injury to multiple organs, mainly the kidney, heart, brain and peripheral nervous system. The literature on FD and central nervous system involvement is scarce when focusing on alterations beyond cerebrovascular disease and is nearly absent in regard to synaptic dysfunction. In spite of that, reports have provided evidence for the CNS’ clinical implications in FD, including Parkinson’s disease, neuropsychiatric disorders and executive dysfunction. We aim to review these topics based on the current available scientific literature.

Neuropsychiatric Symptoms and Their Association With Sex, Age, and Enzyme Replacement Therapy in Fabry Disease: A Systematic Review

Patients suffering from Fabry disease (FD) have an increased risk of developing neuropsychiatric symptoms (NPS), mostly impairment in cognitive performance and depression. Single cases of psychosis have been reported, however, their association with FD can be coincidental. Furthermore, deficits in social functioning and adaptation as well as specific coping styles in FD patients were observed. Recent studies focused on a longitudinal course of the disease and identified risk factors associated with specific NPS. Since 2001, enzyme replacement therapy (ERT) has been available and in preliminary studies seems to improve cognitive impairment and adaptive skills. In this systematic review, we analyze the available literature on the NPS in FD and investigate if there are any differences in their distribution between males and females, children/adolescents and adults, and individuals treated with ERT and untreated. We discuss the role of the psychological, environmental, and molecular alterations and their correlation to psychiatric manifestations in FD. Finally, we would like to increase awareness of the spectrum of NPS in FD.

First manifestation of Fabry's disease by psychotic episode associated with thalamic ischemic stroke - case report and review of literature

Fabry's disease is a X-linked inherited multisystem disorder with deficient activity of the lysosomal enzyme α-galactosidase which neuropsychiatric manifestations comprise mainly small fiber neuropathy, cerebral microangiopathy, and depression. This report describes a patient in who psychotic symptoms were associated with a thalamic ischemic stroke and the first manifestation of Fabry's disease. Reviewing the current literature and the hitherto reported cases of psychosis in Fabry's disease, the inclusion of psychiatric exploration and screening in the routine examination of patients with Fabry's disease as well as a brain MRI on initial diagnosis of Fabry's disease should be considered.

Attention Deficits and ADHD Symptoms in Adults with Fabry Disease-A Pilot Investigation

The present pilot study examines subjective reported symptoms of attention-deficit/hyperactivity (AD/H) in adults with Fabry disease (FD) in comparison with existing normative control data. Existing data from 69 adults with FD via the Achenbach System of Empirically Based Assessment Adult Self-Report questionnaire were analyzed. The results demonstrated a higher prevalence of AD/H symptoms in adults with FD than in the general United States population, with a roughly equal endorsement of Inattention/Attention Deficit symptoms (AD), Hyperactivity-Impulsivity (H-I) symptoms, and Combined Inattention/hyperactivity-impulsivity (C) symptoms. No gender differences were observed. While all subjects endorsing H-I symptoms fell into the symptomatic range on the AD/H scale, only two-thirds of subjects endorsing AD did so. This suggests that attention difficulties with FD are not solely explained by ADHD. Adults with FD who endorsed the AD, H-I, and C symptoms were also more likely to report mean adaptive functioning difficulties. These findings support the growing literature regarding attention difficulties in adults with FD, as well as suggesting a previously unrecognized risk of AD/H symptoms. Future research involving the objective assessment of ADHD in adults with FD is recommended. When serving adults with FD clinically, healthcare professionals should address multiple areas of care, including physical, psychological, and cognitive arenas.

A long-term neuropsychological evaluation in Fabry disease

Fabry disease (FD) is a X-linked multi-systemic metabolic disorder with mainly renal, cardiac and neurological dysfunction. The neuropsychological impact is still unclear, with previous study results ranging from disturbance of speed of information processing and executive functions to a normal cognitive profile. The aim of our study was to gain further insight into the neuropsychological involvement of FD. Patients with genetically proven FD were enrolled at the Ghent University Hospital by their treating neurologist. We evaluated the cognitive status of each patient by a thorough neuropsychological test battery and these exact same neuropsychological assessments were repeated after a follow-up period of 2-4 years and at a second follow-up moment 1-4 years after the first follow-up. Thirteen patients with FD were included (8 female) with mean age of 41.5 years (SD ± 13.9) at baseline. All patients had normal neuropsychological test results on the subtests included in the cognitive battery at baseline, according to age-, gender- and education matched normative data. At the first follow-up moment (2-4 years after baseline), six patients were included (3 male), mean age 45.3 years. At the second follow-up (1-4 years after first follow-up), four patients (2 male) were included, with mean age 45 years. Both at the first and second follow-up moments, all patients obtained normal scores on the subtests. The cognitive functioning appeared to be in the normal range at baseline and did not decline over a follow-up period of 3-8 years, suggesting that cognition in FD patients may be well-preserved in time.

Fabry disease: GLA deletion alters a canonical splice site in a family with neuropsychiatric manifestations

Fabry disease (FD) is a rare X-linked glycosphingolipidosis caused by mutations in GLA, a gene responsible for encoding α-galactosidase A, an enzyme required for degradation of glycosphingolipids, mainly globotriaosylceramide (Gb3) in all cells of the body. FD patients present a broad spectrum of clinical phenotype and many symptoms are shared with other diseases, making diagnosis challenging. Here we describe a novel GLA variant located in the 5' splice site of the intron 3, in four members of a family with neuropsychiatric symptoms. Analysis of the RNA showed the variant promotes alteration of the wild type donor site, affecting splicing and producing two aberrant transcripts. The functional characterization showed absence of enzymatic activity in cells expressing both transcripts, confirming their pathogenicity. The family presents mild signs of FD, as angiokeratoma, cornea verticillata, acroparesthesia, tinnitus, vertigo, as well as accumulation of plasma lyso-Gb3 and urinary Gb3. Interestingly, the man and two women present psychiatric symptoms, as depression or schizophrenia. Although psychiatric illnesses, especially depression, are frequently reported in patients with FD and studies have shown that the hippocampus is an affected brain structure in these patients, it is not clear whether the Gb3 accumulation in the brain is responsible for these symptoms or they are secondary. Therefore, new studies are needed to understand whether the accumulation of Gb3 could produce neuronal alterations leading to psychiatric symptoms.

European expert consensus statement on therapeutic goals in Fabry disease

BACKGROUND

Fabry disease, an inherited lysosomal storage disorder, causes multi-organ pathology resulting in substantial morbidity and a reduced life expectancy. Although Fabry disease is an X-linked disorder, both genders may be affected, but generally to a lesser extent in females. The disease spectrum ranges from classic early-onset disease to non-classic later-onset phenotypes, with complications occurring in multiple organs or being confined to a single organ system depending on the stage of the disease. The impact of therapy depends upon patient- and disease-specific factors and timing of initiation.

METHODS

A European panel of experts collaborated to develop a set of organ-specific therapeutic goals for Fabry disease, based on evidence identified in a recent systematic literature review and consensus opinion.

RESULTS

A series of organ-specific treatment goals were developed. For each organ system, optimal treatment strategies accounted for inter-patient differences in disease severity, natural history, and treatment responses as well as the negative burden of therapy and the importance of multidisciplinary care. The consensus therapeutic goals and proposed patient management algorithm take into account the need for early disease-specific therapy to delay or slow the progression of disease as well as non-specific adjunctive therapies that prevent or treat the effects of organ damage on quality of life and long-term prognosis.

CONCLUSIONS

These consensus recommendations help advance Fabry disease management by considering the balance between anticipated clinical benefits and potential therapy-related challenges in order to facilitate individualized treatment, optimize patient care and improve quality of life.

Cognitive Impairments and Subjective Cognitive Complaints in Fabry Disease: A Nationwide Study and Review of the Literature

Fabry disease is a rare progressive X-linked lysosomal storage disorder which leads to neuropathic pain, organ dysfunction and cerebral pathology. Few studies have investigated cognitive impairment in Fabry disease and these previous studies are difficult to compare due to heterogeneous methodological designs and small cohorts. The objective was to investigate the frequency of cognitive impairment in the Danish nationwide cohort of Fabry patients. Further, we examined if subjective cognitive complaints were associated with objective cognitive performances in this patient group. Neuropsychological tests (17 measures) and evaluation of subjective complaints with the Perceived Deficits Questionnaire (PDQ) were applied in 41 of 63 patients. According to an a priori definition, 12 patients (29.3%) were cognitively impaired. Tests tapping psychomotor speed, attention and executive functions had the highest frequency of impairment. In general, disease related variables as Mainz Severity Score Index, enzyme activity and years since onset and depression did not have a significant impact on the categorisation of patients as being cognitively impaired or non-impaired. Thus, cognitive impairment in Fabry disease does not seem to occur solely by having symptoms for many years or by having high disease burden. However, impaired neuropsychological test results were significantly more common in patients with cerebrovascular disease. Only three patients had scores in the abnormal range of the PDQ scale and subjective perceptions of cognition were not associated with cognitive performances. The levels of subjective cognitive complaints were generally very low in the studied patients demonstrating that the absence of subjective cognitive complaints does not exclude the presence of objective cognitive problems.

The Psychosocial Impact of Fabry Disease on Pediatric Patients

Fabry disease (FD) is a multisystemic disease that has previously been reported to result in poorer quality of life and psychosocial functioning in impacted adults. However, prior to the current study, limited data were available on the impact of FD in children and adolescents. Therefore, the present study examined the differences of quality of life, psychosocial functioning, and depression in children with FD as compared with a healthy sample. Results indicated that children with FD were experiencing poorer quality of life than their healthy counterparts. Notably, results consistently identified adolescents with FD as more heavily impacted than younger children, although not to the same degree as adults with FD as reported in previous studies. Therefore, adolescence may be a critical point in the development of individuals with FD during which effective multidisciplinary interventions could be utilized to prevent poor quality of life and psychosocial functioning in adulthood.

The neurocognitive impact of Fabry disease on pediatric patients

Fabry disease (FD) is an X-linked lysosomal storage disorder that results in progressive multisystemic organ complications. Several studies have examined neurocognitive impairments in adults; however, there is a paucity of research examining neurocognitive functioning in children with FD. This is the first exploratory study to examine the neurocognitive functioning of pediatric patients with FD and to evaluate the effects of enzyme replacement therapy (ERT) on neurocognitive functioning within this population. Families attending a national conference with at least one child with FD and one parent affected by FD comprised the sample (n = 48; 24 pediatric patients, 24 parents). Pediatric participants (10 males, 14 females) between the ages of 6 and 18 years and their parent(s) were involved in the study. Data from a demographic questionnaire and two neurocognitive self-report and parent-report measures were analyzed. Parent reports of neurocognitive functioning were also compared to a sample of children with and without head injury and to a sample of children who had undergone liver transplant (LT). Children with FD had poorer cognitive and executive functioning than healthy peers, and were comparable to children with head injury and LT. In addition, children using ERT had higher scores on measures of overall cognitive functioning, as well as fewer problems with attention/working memory and executive functioning. Results of this study suggest that children with FD may exhibit poorer cognitive and executive functioning relative to healthy peers. The use of ERT may mitigate the negative impact of FD on neurocognitive functioning in pediatric patients.

Cognitive function in adults aging with fabry disease: a case-control feasibility study using telephone-based assessments

We examined the feasibility of recruiting US adults ≥45 years old with Fabry disease (FD) for telephone assessments of cognitive functioning. A case-control design matched each FD participant on age, sex, race, and education to four participants from a population-based study. Fifty-four participants with FD age 46-72 years were matched to 216 controls. Standardized cognitive assessments, quality of life (QOL), and medical histories were obtained by phone, supplemented by objective indices of comorbidities. Normalized scores on six cognitive tasks were calculated. On the individual tasks, scores on list recall and semantic fluency were significantly lower among FD participants (p-values < 0.05), while scores on the other four tasks did not differ. After averaging each participant's normalized scores to form a cognitive composite, we examined group differences in composite scores, before and after adjusting for multiple covariates using generalized estimating equations. The composite scores of FD cases were marginally lower than controls before covariate adjustments (p = 0.08). QOL and mental health variables substantially attenuated this finding (p = 0.75), highlighting the influence of these factors on cognition in FD. Additional adjustment for cardiovascular comorbidities, kidney function, and stroke had negligible impact, despite higher prevalence in the FD sample. Telephone-based cognitive assessment methods are feasible among adults with FD, affording access to a geographically dispersed sample. Although decrements in discrete cognitive domains were observed, the overall cognitive function of older adults with FD was equivalent to that of well-matched controls before and after accounting for multiple confounding variables.

Cognitive and psychological functioning in Fabry disease

Fabry disease is an X-linked lysosomal storage disorder which can result in renal, cardiac, and cerebrovascular disease. Patients are at increased risk of stroke and neuroimaging studies note cerebrovascular pathology. This study provides a cognitive profile of a cohort of individuals with Fabry disease and investigates the impact of pain, age, renal, cardiac, and cerebrovascular functioning on cognition and psychological functioning. Seventeen Fabry patients (12 males) with ages ranging 25 to 60 years (M = 46.6+11.8), and 15 age-matched healthy controls (M = 46.2+12.7) were administered a comprehensive neuropsychological battery. Fabry males demonstrated slower speed of information processing, reduced performance on measures of executive functions (verbal generation, reasoning, problem solving, perseveration), were more likely to show clinically significant reductions, and were more likely to report symptoms of anxiety and depression. Conversely, Fabry females performed at a similar level to controls. Correlational analyses indicated a link between cognitive and clinical measures of disease severity.

Inherited leukoencephalopathies with clinical onset in middle and old age

The currently widespread use of neuroimaging has led neurologists to often face the problem of the differential diagnosis of white matter diseases. There are various forms of leukoencephalopathies (vascular, inflammatory and immunomediated, infectious, metabolic, neoplastic) and sometimes white matter lesions are expression of a genetic disease. While many inherited leukoencephalopathies fall in the child neurologist's interest, others may have a delayed or even a typical onset in the middle or old age. This field is rapidly growing and, in the last few years, many new inherited white matter diseases have been described and genetically defined. A non-delayed recognition of middle and old age inherited leukoencephalopathies appears important to avoid unnecessary tests and therapies in the patient and to possibly anticipate the diagnosis in relatives. The aim of this review is to provide a guide to direct the diagnostic process when facing a patient with a suspicion of an inherited form of leukoencephalopathy and with clinical onset in middle or old age. Based on a MEDLINE search from 1990 to 2013, we identified 24 middle and old age onset inherited leukoencephalopathies and reviewed in this relation the most recent findings focusing on their differential diagnosis. We provide summary tables to use as a check list of clinical and neuroimaging findings that are most commonly associated with these forms of leukoencephalopathies. When present, we reported specific characteristics of single diseases. Several genetic diseases may be suspected in patients with middle or old age and white matter abnormalities. In only few instances, pathognomonic clinical or associated neuroimaging features help identifying a specific disease. Therefore, a comprehensive knowledge of the characteristics of these inherited white matter diseases appears important to improve the diagnostic work-up, optimize the choice of genetic tests, increase the number of diagnosed patients, and stimulate the research interest in this field.

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.

The neuropsychiatry of inborn errors of metabolism

A number of metabolic disorders that affect the central nervous system can present in childhood, adolescence or adulthood as a phenocopy of a major psychiatric syndrome such as psychosis, depression, anxiety or mania. An understanding and awareness of secondary syndromes in metabolic disorders is of great importance as it can lead to the early diagnosis of such disorders. Many of these metabolic disorders are progressive and may have illness-modifying treatments available. Earlier diagnosis may prevent or delay damage to the central nervous system and allow for the institution of appropriate treatment and family and genetic counselling. Metabolic disorders appear to result in neuropsychiatric illness either through disruption of late neurodevelopmental processes (metachromatic leukodystrophy, adrenoleukodystrophy, GM2 gangliosidosis, Niemann-Pick type C, cerebrotendinous xanthomatosis, neuronal ceroid lipofuscinosis, and alpha mannosidosis) or via chronic or acute disruption of excitatory/inhibitory or monoaminergic neurotransmitter systems (acute intermittent porphyria, maple syrup urine disease, urea cycle disorders, phenylketonuria and disorders of homocysteine metabolism). In this manuscript we review the evidence for neuropsychiatric illness in major metabolic disorders and discuss the possible models for how these disorders result in psychiatric symptoms. Treatment considerations are discussed, including treatment resistance, the increased propensity for side-effects and the possibility of some treatments worsening the underlying disorder.

Fabry disease

Fabry disease (FD) is a progressive, X-linked inherited disorder of glycosphingolipid metabolism due to deficient or absent lysosomal α-galactosidase A activity. FD is pan-ethnic and the reported annual incidence of 1 in 100,000 may underestimate the true prevalence of the disease. Classically affected hemizygous males, with no residual α-galactosidase A activity may display all the characteristic neurological (pain), cutaneous (angiokeratoma), renal (proteinuria, kidney failure), cardiovascular (cardiomyopathy, arrhythmia), cochleo-vestibular and cerebrovascular (transient ischemic attacks, strokes) signs of the disease while heterozygous females have symptoms ranging from very mild to severe. Deficient activity of lysosomal α-galactosidase A results in progressive accumulation of globotriaosylceramide within lysosomes, believed to trigger a cascade of cellular events. Demonstration of marked α-galactosidase A deficiency is the definitive method for the diagnosis of hemizygous males. Enzyme analysis may occasionnally help to detect heterozygotes but is often inconclusive due to random X-chromosomal inactivation so that molecular testing (genotyping) of females is mandatory. In childhood, other possible causes of pain such as rheumatoid arthritis and 'growing pains' must be ruled out. In adulthood, multiple sclerosis is sometimes considered. Prenatal diagnosis, available by determination of enzyme activity or DNA testing in chorionic villi or cultured amniotic cells is, for ethical reasons, only considered in male fetuses. Pre-implantation diagnosis is possible. The existence of atypical variants and the availability of a specific therapy singularly complicate genetic counseling. A disease-specific therapeutic option - enzyme replacement therapy using recombinant human α-galactosidase A - has been recently introduced and its long term outcome is currently still being investigated. Conventional management consists of pain relief with analgesic drugs, nephroprotection (angiotensin converting enzyme inhibitors and angiotensin receptors blockers) and antiarrhythmic agents, whereas dialysis or renal transplantation are available for patients experiencing end-stage renal failure. With age, progressive damage to vital organ systems develops and at some point, organs may start to fail in functioning. End-stage renal disease and life-threatening cardiovascular or cerebrovascular complications limit life-expectancy of untreated males and females with reductions of 20 and 10 years, respectively, as compared to the general population. While there is increasing evidence that long-term enzyme therapy can halt disease progression, the importance of adjunctive therapies should be emphasized and the possibility of developing an oral therapy drives research forward into active site specific chaperones.