Nasal continuous positive airway pressure (CPAP) is the primary treatment for symptomatic patients with obstructive sleep apnoea-hypopnoea (OSAH). The best method for determining the optimal CPAP pressure is an ongoing subject of scrutiny. Both the American Academy of Sleep Medicine¹ and the American Thoracic Society² recommend supervised CPAP titration during overnight polysomnography, based on the premise that the early establishment of optimal CPAP pressure will improve compliance with treatment. However, a recent large multicentre study³ has challenged the validity of in-laboratory CPAP titration by showing that this approach has no advantage when compared with ambulatory methods. In this issue of Thorax, West and colleagues⁴ further advance the case for simpler methods of CPAP pressure determination in the home.

OSAH is a common condition for which there is often limited access to appropriate diagnostic testing.⁵ A number of strategies have been proposed to streamline the diagnosis and treatment of patients with OSAH. Predictive algorithms help to speed diagnosis and perhaps identify patients likely to respond to CPAP.^6,7 The widespread use of overnight home monitoring such as oximetry has improved access to diagnostic testing, and this approach is increasingly supported by published reports.^8,9 Several algorithm based approaches have been used with varying degrees of success to determine the optimal CPAP pressure.^3,10 Autotitrating CPAP machines have proved to be effective both in determining the effective pressure¹¹ and as a treatment modality.¹² Recent clinical …