Trio of studies herald new hope for people with schizophrenia
QCMHR’s Physical and Mental Health Research Stream ended 2021 on a high note having published three studies that may herald new treatment options and improved quality of life for people with schizophrenia.
Patients with schizophrenia die almost 20 years earlier than the general population mostly due to avoidable illnesses like diabetes and heart disease related to antipsychotic medications and lifestyle factors.
Physical and Mental Health Research Stream Leader, Professor Dan Siskind, who is also a psychiatrist at the Princess Alexandra Hospital, said the first of the three studies sought to determine rates of a severe, treatment-resistant form of schizophrenia by examining the clinical history of patients after they had their first episode of psychosis.
“Treatment-resistant schizophrenia (TRS) does not respond to first line antipsychotic therapy and is associated with high levels of functional impairment, healthcare usage, and poor quality of life,” Professor Siskind said.
“Our study was important for accurately quantifying rates of this condition to improve patients’ access to clozapine, a drug proven most effective for treating the condition.
“We ultimately found that one in three people will develop TRS.”
Having established rates of TRS, Professor Siskind and his team then set their sights on trialling a drug to prevent patients on clozapine from weight gain – an adverse side effect of clozapine use.
“There is limited evidence about interventions that can minimise weight gain associated with clozapine therapy, so this second study sought to determine whether a diabetes drug, known as metformin, can prevent weight gain or initiate weight loss in patients taking clozapine,” Professor Siskind said.
“While the study was prematurely closed due to COVID-19, the results were promising, showing that weight gain may be prevented in patients who commence clozapine and metformin simultaneously.”
The final study of the trio sought to refine how much clozapine patients should take to minimise psychotic symptoms and adverse side effects.
He said that Clozapine blood levels may be a more useful predictor of therapeutic response than the dose, and the study found that the window of 350-600 mg/L provided the best balance between improvement in psychotic symptoms and adverse effects of clozapine,” Professor Siskind said.
“This study has the potential to influence clozapine therapeutic drug monitoring to improve outcomes for people with treatment refractory schizophrenia.”
Overall, Professor Siskind said that the studies demonstrate the need to identify innovative treatments to improve the quality of life for people living with schizophrenia by meeting their physical and psychological health needs.
The Physical and Mental Health Research Stream will be leading three new clinical trials in 2022, all funded by competitive grants: the first will explore the role of the diabetes medication, semaglutide, for helping with weight loss among people on clozapine; the second will examine one of the compounds in marijuana, cannabidiol, for reducing psychotic symptoms in people who do not respond adequately to clozapine; and the third will evaluate the role of a comprehensive medical assessment for people with severe mental illness to better treat physical health comorbidity.
The studies were published in the British Journal of Psychiatry (study 1), Therapeutic Advances in Psychopharmacology (study 2) and Acta Psychiatrica Scandinavica (study 3).