Determinants of altered quality of life in patients with sleep-related breathing disorders. E. Sforza, J.P. Janssens, T. Rochat, V. Ibanez. #ERS Journals Ltd 2003. ABSTRACT: Recent reports have suggested that altered quality of life and well-being are reported by patients with sleep-related breathing disorders (SRBD). There seems to be no data available in the literature on factors underlying these behavioural consequences. In this study, health-related quality of life (HRQL) scores were examined in SRBD patients in order to establish which factors are implicated in these disturbances.The study group consisted of 130 patients: 49 snorers and 81 patients with obstructive sleep apnoea. The Medical Outcome Survey Short Form-36 questionnaire was administered the morning after the sleep study and scores for the eight dimension scores were obtained. Patient9s data were compared to normative sex-and age-matched data.In comparison with normal values, scores for all HRQL dimensions were decreased in SRBD patients, with a greater impact on subscores for "vitality", "physical role", "social functioning", "mental health" and "role emotional" dimensions. While impairment in physical function was mostly influenced by sleep stage and obesity, subjective daytime sleepiness mainly affected the other dimensions.The authors conclude that the altered health-related quality of life of sleep-related breathing disorder patients is a multifactorial phenomenon depending on the interaction of sleep stages, daytime sleepiness and obesity, with no significant contribution of sleep fragmentation, hypoxaemia and apnoea recurrence. Sleep-related breathing disorders (SRBD) are common disorders, which affect o2-4% of the general population and are characterised by repetitive pharyngeal collapse during sleep, inducing sleep fragmentation and nocturnal hypoxaemia. These two factors have been suggested as causal factors of the excessive daytime sleepiness and neuropsychological and cognitive disturbances affecting the daytime functioning of these patients. Several studies have demonstrated that a large number of patients with SRBD may also have altered health-related quality of life (HRQL) scores, using either generic questionnaires, such as the Nottingham Health Profile [1,2] or the Medical Outcome Survey Short Form (SF)-36 [3], or disease-specific questionnaires, such as the Calgary Sleep Apnea Quality of Life [4,5]. These all showed impairment more frequently in vitality and social functioning [6]. Despite the frequent association between SRBD and altered daily functioning and well-being [7,8], and the importance of altered quality of life in SRBD [6], no data are available in the literature concerning the mechanisms underlying these psychological disturbances. This could be due, at least in part, to the fact that quality of life scores are not routinely used by clinicians to detect the impact of the sleep disorder on the well-being of their patients [9] and also to the difficulty in defining which parameters better reflect a clinically meaning...