Patients on Enzyme Replacement Therapy May Be Prone to Psychiatric Disorders, Study Suggests

Patients on Enzyme Replacement Therapy May Be Prone to Psychiatric Disorders, Study Suggests

Gaucher disease patients on enzyme replacement therapy may be prone to psychiatric disorders, according to an Egyptian team of researchers.

Their study, “Psychiatric manifestations in Egyptian Gaucher patients on enzyme replacement therapy,” was published in the Journal of Psychosomatic Research.

To date, there are few studies focused on Gaucher’s mental manifestations, but limited evidence suggests the occurrence of mood disorders or schizophrenia together with Gaucher disease in Ashkenazi Jews.

Mutations in the GBA gene — the underlying cause of Gaucher disease — also have been linked to psychiatric symptoms, like depression, in both Parkinson’s disease and dementia with Lewy bodies.

Management therapies for Gaucher disease currently includes enzyme replacement therapy (ERT), which is given as an injection into the vein. However, ERT is not able to treat the mental manifestations of the metabolic disorder because it does not cross the blood-brain barrier.

“With the absence of disease-specific therapies, a better understanding of psychiatric manifestations can assist GD [Gaucher disease] patients, families and treating physicians in their struggle of living with such a chronic illness. Such symptoms have a major impact on patients’ independence, caregiver burden, and mortality,” the investigators said.

To assess the impact of psychological manifestations of Gaucher, researchers at Ain Shams University in Cairo evaluated the occurrence of psychiatric disorders in an Egyptian sample of people with the disease. These individuals were on the same regimen of enzyme replacement therapy.

The patients’ psychiatric symptoms were assessed through the application of a short, structured clinical interview that enabled the diagnosis of psychiatric disorders. The team also looked for associations between the participants’ Gaucher-related medical history and the time they started taking ERT.

Of the 22 participants — 11 women and 11 men, some of whom were teenagers — 13 were diagnosed with Gaucher disease type 1, which is the non-neurological form of the disorder. The remaining nine had Gaucher disease type 3, which has brain involvement, but not as severe as seen in Gaucher type 2.

Results revealed that 41% of patients had psychiatric manifestations — “with the most common being depression followed by generalized anxiety disorder,” the researchers said. Surprisingly, none of the participants were receiving psychiatric treatment.

Compared to those without neurological symptoms, patients’ psychiatric symptoms were not related to the age of presentation, gender, family history of psychiatric disorders, intelligence quotient (IQ), or the brain’s bioelectric activity.

Genetic testing showed that, despite having a non-neurological form of the disease, individuals with Gaucher type 1 still made up 45.5% of the sample with psychiatric disorders.

When comparing patients with and without psychiatric manifestations, no statistically significant differences were found in GBA enzyme activity at the time of diagnosis, age of start of ERT, disease severity, type of Gaucher disease, or the mutation in the GBA gene.

“Specialty multidisciplinary care centres that focus on integrating medical and psychosocial care for individuals living with metabolic disorders and their families is an unmet need,” the investigators said.

“The current results suggest that GD patients are susceptible to psychiatric disorders. However, these results need to be replicated on a wider scale. These findings are of ultimate importance, considering the lack of integrated services addressing both the medical and psychological aspects of inborn errors of metabolism in many countries,” the team concluded.