Physical Activity and Eating Behaviour Changes in Patients with Obstructive Sleep Apnea Syndrome

University dissertation from Uppsala : Acta Universitatis Upsaliensis

Abstract: This thesis aimed at developing and evaluating a tailored behavioural sleep medicine intervention for enhanced physical activity and healthy eating in patients with obstructive sleep apnea syndrome (OSAS) and overweight.Participants with moderate or severe OSAS (apnea-hypopnea index ?15) and obesity (Studies I-II) or overweight (Studies III-IV), treated with continuous positive airway pressure (CPAP) (Studies I-II) or admitted to CPAP treatment (Studies III-IV), were recruited from the sleep clinic at Uppsala University Hospital, Sweden. Semi-structured individual interviews were analysed using qualitative content analysis (Study I). Data on moderate-to-vigorous physical activity (MVPA) and sedentary time were collected with three measurement methods and analysed regarding the level of measurement agreement (Study II). Potential disease-related and psychological correlates for the amount of MVPA, daily steps and sedentary time were explored using multiple linear regression (Study III). Physical activity and eating behaviour changes were examined after a six month behaviour change trial (Study IV). A tailored behavioural sleep medicine intervention targeting physical activity and healthy eating in combination with first- time CPAP treatment was compared with CPAP treatment and advice on the association between weight and OSAS.According to participants’ conceptions, a strong incentive is needed for a change in physical activity and bodily symptoms, external circumstances and thoughts and feelings influence physical activity engagement (Study I). Compared with accelerometry, the participants overestimated the level of MVPA and underestimated sedentary time when using self-reports (Study II). The participants spent 11 hours 45 minutes (71.6% of waking hours) while sedentary. Fear of movement contributed to the variation in steps and sedentary time. Body mass index was positively correlated to MVPA (Study III). The experimental group increased intake of fruit and fish and reduced more weight and waist circumference compared with controls. There were no changes in physical activity (Study IV).The novel tailored behavioural sleep medicine intervention combined with first-time CPAP facilitated eating behaviour change, with subsequent effects on anthropometrics, but it had no effects on physical activity and sedentary time. Fear of movement may be a salient determinant of sedentary time, which has to be further explored in this population. The results confirm sedentary being a construct necessary to separate from the lower end of a physical activity continuum and highlight the need of developing interventions targeting sedentary behaviours specifically.