The imperative to screen for obstructive sleep apnoea in people with schizophrenia

Hubbeling et al. (2017) argue that a screening tool specific to people prescribed antipsychotic medication is required to overcome the challenges associated with screening for obstructive sleep apnoea (OSA) in people with schizophrenia. They also assert that routine screening should not be undertaken due to the known metabolic issues affecting this patient group and the limited evidence of continuous positive airway pressure (CPAP) improving cardiovascular function. The idea of ignoring a treatable, often iatrogenic condition solely because most patients would score high on routine screening measures should be an anathema to psychiatrists. It contradicts the recent Royal Australian and New Zealand College of Psychiatrist’s Clinical Practice Guideline for Schizophrenia that states ‘(r)egular screening and intervention for cardiometabolic problems in people with Schizophrenia should be mandatory, from the first episode of psychosis’ and its emphasis on the ‘imperative to assess for OSA by questioning about daytime somnolence, snoring and breathing pauses’ (Galletly et al., 2016). Identifying and treating OSA have the potential to reduce daytime somnolence and improve physical quality of life in a population already sedated with antipsychotics and with high levels of co-morbid physical illness (Galletly et al., 2016).

There has been limited research examining the relationship between OSA and schizophrenia, and an absence of research looking at the value of screening in this population. The non-availability of such evidence should not be used to infer such screening is not relevant. Myles et al. (2016) present a strong argument for both screening and further research in this area.

From our clinical experience, we support the call for screening for OSA in patients with schizophrenia (Myles et al., 2017). A nurse-led initiative at one of our community care units (CCU) screened 16 residents, not already using CPAP, for OSA using the STOP-BANG questionnaire (Chung et al., 2012). The screening was driven by feedback from a service user on clozapine commenced on CPAP for OSA who reported a subjective benefit in mood, anxiety and alertness. Most of these residents were male (14/16) and diagnosed with schizophrenia or a related psychotic disorder (13/16). The average age of the group was 36 years, and the median body mass index was 29 (range: 19.3–61.4) kg/m².

Screening identified nine high-risk service users, eight of whom had a diagnosis of schizophrenia or a related psychotic disorder. All of the high-risk service users were overweight, with a neck circumference of >40 cm and suffering from morning somnolence. Additionally, four of these people had been observed snoring loudly by unit staff. Two completed polysomnography at a bulk billing private clinic, and both were diagnosed with OSA; one was commenced on CPAP, and the other is awaiting a fitting for CPAP. The consumer commenced on CPAP reported significantly reduced napping and daytime somnolence. Four of the remaining patients have declined polysomnography, two are awaiting polysomnography coordination, and one is awaiting guardian consent.

While our sample is small, screening showed that over half of service users in our CCU had a level of high risk. Although uptake was low, all who had polysomnography had their presumptive diagnosis of OSA confirmed and those commenced on CPAP found benefit. The perfect is the enemy of the good, and as such, we should screen our service users now with existing tools such as the STOP-BANG, rather than waiting for the ideal OSA screening tool. Additionally, increased provision of home polysomnography may improve access to diagnostic testing for people with OSA (Myles et al., 2017). Not offering or arranging screening for a common medical condition in a patient group at elevated risk due to iatrogenic effects of treatment limits patient choice and risks further marginalisation and social exclusion.

See Letter by Hubbeling et al., 51: 294–295.