8 factors that make CPAP less effective

​​​​​​​A nationwide French study finds choice of mask, age and sex are all important
Clare Pain
Man wearing CPAP orofacial mask

Patients with obstructive sleep apnoea who opt for an oronasal rather than nasal mask to administer their CPAP treatment may be putting themselves at risk of treatment failure, French researchers say.

The study of nearly 12,300 adults with sleep apnoea using CPAP found that more than one-fifth (22%) had a residual apnoea-hypopnoea index (AHI) in excess of five events per hour on their first check-up after starting treatment.