A Rank Order Evaluation Of Complaints In Patients Suspected Of Sleep Apnea Syndrome

摘要

In 1164 patients suspected of sleep apnea syndrome (SAS), the polysomnography confirmed SAS in 58.6%. The range-order analysis of their complaints evidenced that the average number of complaints was 3.7 and the more frequent complaints were placed earlier in the complaints list. According to their mean scores, there were four complaints places: 1) snoring; 2) insomnia, breathing arrest, gasping and excessive daytime somnolence (EDS); 3) headaches and nausea-vomiting, and 4) memory trouble and erectile dysfunctions. The total number of complaints was significantly correlated with both the apnea index and oxygen desaturation. Snoring, breathing arrest and total number of complaints were higher in patients with confirmed SAS, breathing arrest, EDS and insomnia scores in more severe forms of SAS while headache, erectile dysfunctions and nausea-vomiting scores in central SAS. Such a rank order evaluation of the complaints may be a useful tool for detecting SAS, and for predicting the SAS type and intensity. Introduction Sleep-related breathing disorders (SRBD) are encountered in-between 1 and 5% of the general population, snoring being the first risk factor for developing sleep apnea syndrome (SAS) (1). Untreated SRBD shows an increased risk of car accidents due to increased daytime somnolence and premature death due to cardiovascular complications. Patients with complaints possibly induced by SAS should be further evaluated since CPAP and other treatment lead to significant improvement. When is evaluation necessary? Among all the patients' complaints are those suggesting SRBD, which requires a further investigation? Loud snoring, breathing cessation or gasping during sleep observed by relatives, excessive daytime sleepiness (EDS), headache in the morning, non-refreshing sleep and nocturnal choking sensations in obstructive SAS (17) or EDS or insomnia in central SAS (2,3,18) are also well known signs indicating SAS. Numerous studies analyzed in a various ways their predictive value for SAS or their power to support a further sleep investigation (11,12,13,14,15,16). However, no study performed an analysis of these symptoms according to their place in the whole list of patients' complaints. That is why, in the present study we performed a ranked-order analysis for the predictive value for SAS of the main complaints in a very large population suspected from SAS, referred to a sleep center. Material and Methods Study subjectsThe study was performed on 1164 patients, referred to our Sleep Center for suspicion of SAS during the last 5 years (age>18 years - mean age 46.3±11.6y, range 18-81y, 88.7% male). Inclusion criteria were: age over 18 years, and a complete and correct completion of a questionnaire detailing their complaints and personal data.Study designWe tried to obtain some predictive evaluation from the patient's rank order complaints. The main assumption was that a complaint is more intense (more important for the patient or more disturbing) if it is between the first, and inverse, if a complaint is less important is between the last. Therefore, each complaint received a rank power, which was inverse related to the complaint rank from all the complaints. If a patient had five complaints and snoring was the first one recorded, then snoring received a rank power of 5. If it was the second, its rank power was 4, etc. In this kind of evaluation, if a patient had a single complaint, i.e. snoring, the complaint received a rank power of 1 as in the case of a patient with 8 complaints where the snoring was the last recorded complaint. To prevent the influence of the complaint number on this evaluation, we expressed the rank power in ratio between the complaint rank power and the total number of complaints (i.e. if a patient had five complaints and snoring was the first recorded, then snoring received a rank power of 5/5=1, if it was the second, its rank power was 4/5=0.8, etc.). The value varies between 0 (the complaint not present) to