PHYSICAL ACTIVITY AND MENTAL HEALTH IN AUSTRALIAN ADULTS WITH PSYCHOLOGICAL DISTRESS

INTRODUCTION & AIMS Adults with mental health concerns face compounded barriers to physical activity engagement. We recently conducted a randomised controlled trial to determine whether a lifestyle intervention targeting PA and nutrition was non-inferior to psychotherapy in managing depression (the CALM non-inferiority trial). While we demonstrated non-inferiority, participants assigned to the lifestyle intervention demonstrated improvements in dietary adherence and intake but not self-reported activity measures. The aim of this sub-study was to analyse actigraphy-derived measures to identify whether objective changes occurred and determine whether these were associated with mental health. METHODS This study included a sub-set of 36 of the 70 participants assigned to the lifestyle therapy intervention from the larger trial (ACTRN12621000387820) who were recruited based on indicative depression (Distress Questionnaire Scale 8+). A Fitbit Charge-2 measured daily steps (n), distance travelled (km), floors climbed (n) and minutes in sedentary, light, moderate and vigorous activity. Questionnaires measured psychological distress (Kessler-10), anxiety (Generalised Anxiety Disorder scale-7) and depressive symptoms (Patient Health Questionnaire-9). Linear mixed models determined within-group change over time. Spearman rank correlation coefficients examined associations between change scores over 8-weeks. RESULTS From baseline to 8-week follow-up, floors climbed increased 38% (mean change [95%CI]: 2.8 [0.0, 5.5], P=0.047) and minutes sedentary increased 9% (66.9 [20.8, 133.0], P=0.004). We found no change in daily steps, distance travelled, or minutes spent lightly, moderately, or vigorously active. Reducing sedentary time was associated with reduced depressive symptoms (rs=0.350, P=0.043), similarly increasing time spent in vigorous activity was associated with reduced psychological distress (rs=0.346, P=0.045). CONCLUSION Changes in activity were mixed, however vigorous physical activity and reduced sedentary time were associated with improved mental health in adults with psychological distress participating in a lifestyle therapy intervention for depression. Future investigations should seek to quantify minimum changes required to benefit mental health in this vulnerable population.