Integrated movement behaviours in children with chronic disease: an observational case-control study

The prevalence of chronic diseases has increased in children and adolescents and physical inactivity, sedentary lifestyle and obesity have been identified as risk factors for earlier onset of chronic disease. Times spent in 24-hour movement behaviours have become important public health concerns because of their potential to impact on an individual’s health. The concept of 24-hour movement behaviours - comprising physical activity (PA), sedentary behaviour and sleep - is relatively new and quantifying the various movement behaviours with confidence is still a challenge. The adequacy of levels of 24-hour movement behaviors in children with chronic disease is unknown as is whether there are systematic differences between children with chronic disease and their healthy peers. Aims: To examine the habitual amount of time spent in moderate to vigorous physical activity (MVPA) and sedentary time (ST) in children and adolescents with chronic disease and in children and adolescents with obesity; to compare measured MVPA against MVPA recommendations in children with chronic disease and their healthy peers and to investigate 24 hour-movement behaviours (PA, standing, sedentary and sleep behaviours – sleep; quantity and sleep quality) for 5-7 days in children with chronic childhood diseases and test whether there were differences between children with chronic disease and their healthy peers. In systematic literature reviews (Chapters III and IV): the literature searching was focused on four key elements: children and/or adolescents, MVPA, ST and/or SB, measured objectively by accelerometer, and common chronic disease (obesity, chronic cardiovascular disease, chronic respiratory disease, diabetes mellitus and malignancies). For each review, an extensive search was carried out in the five most relevant electronic databases: Medline, Cochrane library, EMBASE, SPORTDiscus and CINAHL from 2000. Study selection: Studies with accelerometer-measured MVPA and/or SB (at least 3 days and 6 hours/day) in children and adolescents (0-19 years) with cardiovascular disease, respiratory disease, diabetes, malignancy and obesity, studied while well and clinically stable. Study quality was assessed formally. Meta-analyses were planned for all outcomes. In the systematic review of MVPA and ST in children and adolescents with chronic disease, 25 studies were eligible, in four chronic disease categories: cardiovascular disease (7 studies), respiratory disease (7 studies), diabetes (8 studies), and malignancy (3 studies). Patient MVPA was generally below the recommended 60 min/day and ST was generally high regardless of the disease condition. Comparison with healthy controls suggested no marked differences. MVPA in children with chronic disease was not very much lower than in healthy control or comparison groups with the exception of children being treated for malignancy. In the systematic review of MVPA and ST in children and adolescents with obesity, 26 studies were eligible (n=14,739 participants; n=3523 with obesity); 6/26 studies involved children aged 0 to 10 years and 18/26 involved adolescents aged 10.1 to19 years. In the participants with obesity, time spent in MVPA was consistently below the recommended 60 min/day, and ST was generally high regardless of the participant’s age and sex. Comparison with controls suggested that the time spent in MVPA was significantly lower in children and adolescents with obesity, though differences were relatively small. There were no marked differences in ST between obese study participants and their non-obese peers. The primary data collection studies (Chapters V and VI) were based on an observational case-control study of 24-hour movement behaviours in children with common chronic diseases likely to disrupt these behaviours, and included 160 participants; 80 children with chronic disease; 20 with type 1 diabetes mellitus (T1DM), 20 with juvenile idiopathic arthritis (JIA), 20 with congenital heart disease (CHD), 20 with cystic fibrosis (CF). Patients were recruited from outpatient clinics at the Royal Hospital for Children, Glasgow. 80 healthy children were individually pair-matched for age, sex, and timing of measures. Habitual time spent in PA, standing, sedentary and sleep behaviours – sleep quantity – particularly sleep timing (sleep onset/offset), and sleep duration - and sleep quality) and step counts were all measured with the activPAL accelerometer/inclinometer over 7 days. Comparisons against recommendations were made and differences between the groups with chronic disease and controls examined. Mean time spent in PA and step counts per day were consistently lower in the children with chronic disease compared to healthy controls, reaching statistical significance only for the T1DM and CHD groups. Only 20/80 children with chronic disease and 29/80 controls met the daily step count recommendations. ST was consistently higher in children with chronic disease, though this reached significance only for the group with CF. Time spent asleep was slightly greater in the children with chronic disease, significant only for the group with JIA. Sleep disruption was consistently greater in those with chronic disease, reaching significance for groups with T1DM, CHD and CF. When data from the groups of children with chronic disease and controls were combined, permitting a comparison of 80 vs 80 children respectively in the primary data collection studies, differences between children with chronic disease and healthy controls were more obvious when the children with chronic disease were compared as a single group with their healthy controls. The most important finding was that there were significant differences between children with chronic disease and healthy controls for ST, standing, PA and sleep. Those with chronic disease had greater time spent sedentary with significantly lower number of sedentary breaks, less standing time with slightly longer sleep time than their healthy controls. Time spent in PA was significantly lower (in both PA time and steps counts) in children with chronic disease compared to healthy controls. The most obvious concerns in the present study arise from differences between patient and control groups with patient group showing greater ST, with consistently lower number of sitting bouts and lower PA levels than their healthy controls. However, differences between patient and control groups for the 24-h movement behaviours were generally quite small in the children studied and their biological significance of the differences is unclear. Finally, optimising levels of 24-hour movement behaviours should confer a number of benefits for child health, development, and wellbeing. There is a need for further research with a clinical focus on these behaviours in those with chronic disease