[Predictive factors in maintaining nocturnal continuous positive pressure in patients with sleep apnea syndrome]

A retrospective study was carried out on 347 case notes involving 303 men and 44 women who were suffering from a sleep apnea syndrome (SAS). The mean age was 57 plus or minus 10 years, and the diagnosis was made between 1982 and 1992. We have carried out the research to examine if there were clinical factors or factors related to respiratory function which would predict the acceptance in the short or long term and the correct observation in a daily time-table of nocturnal continuous positive pressure (PPC). The diagnosis of SAS was made using conventional polygraphy (35%), computerised cardiorespiratory recording 38%, or limited to transcutaneous saturation 27%. The mean number of respiratory nocturnal events in the three groups were respectively 48 plus or minus 25 per hour during sleep, and 45 plus or minus 23 and 51 plus or minus 20 per hour by the recording techniques. We have suggested a treatment by PPC in 235 patients: 86 patients refused at the outset (37%), 26 stopped secondarily (11%), and 108 (46%) continued until the end point 1992 with a mean duration of treatment of 24 (plus or minus 17), months and a mean duration of nocturnal usage of 6.2 (plus or minus 2.5) hours a mean level of positive pressure of 11 (plus or minus) 2) centimetres. The primary acceptance of PPC is significantly linked to the understanding of the patient of the functional signs (p less than 0.001) and of the severity of diurnal hypersomnolence (p less than 0.001). The acceptance in the long-term is linked in a weakly significant manner to the recognition by the patient of functional signs (p less than 0.04). None of the other 68 criteria used for assessing the severity of the patient and the SAS had any influence on the acceptance of PPC in short or long term. The compliance with a daily time-table is a weakly significant factor to the severity of the SAS judged by the number of nocturnal respiratory events (p less than 0.03).