Sleep-disordered breathing in stable methadone programme patients: a pilotstudy

Aims. To explore the possibility that stable MMP patients have sleep-disord ered breathing (SDB) and abnormal sleep architecture defined by nocturnal s leep stages and sleep efficiency. Design. Observational. Setting. Regional Methadone Service and sleep disorders laboratory in a university affiliated hospital. Participants and measurements. Ten stable MMP patients and nine normal subjects were assessed clinically and with overnight polysomnography . Findings. There were no differences in age, sex and body mass index betwe en the groups. The methadone dose ranged between 50 and 120 mg/day. Six pat ients had central apnoea index (CAI) greater than 5, four had a CAI greater than 10 and three of these exhibited periodic breathing. No normal subject had central sleep apnoea. The patients had lower sleep efficiency (p<0.05) , less slow wave sleep (p<0.01), less rapid eye movement sleep (p<0.05) and more Stage 2 sleep (p<0.05) than controls. Conclusions. Stable MMP patient s have more sleep architecture abnormalities than controls and a higher pre valence of central sleep apnoea. Further studies are needed to confirm thes e findings, to delineate the mechanisms for the abnormalities and to assess whether the SDB is related to sudden death in stable MMP patients. We reco mmend that MMP patients have awake and sleep respiration assessed to identi fy those potentially at risk.