Do Mental Health Challenges Affect Exercise Tolerance In Adolescent Dysautonomia Patients?

Abstract

PURPOSE: Adolescents experience a myriad of symptoms due to transient dysfunction of the autonomic nervous system during puberty (Dysautonomia of Adolescence, DAOA). Symptoms can be debilitating and can impact mental health. Exercise intolerance is commonly reported. We sought to determine if mental health challenges are associated with reduced exercise tolerance in DAOA patients. METHODS: This is a retrospective chart review of all patients seen in a tertiary level DAOA clinic between January 2017 and November 2019. Exercise tolerance tests were performed on a treadmill using an institutional (BCCH) protocol. Patients were encouraged to exercise to volitional fatigue and aimed to achieve a heart rate (HR) >200 bpm. Treadmill time, supine HR, peak HR, and % predicted HR at peak exercise were recorded for all DAOA patients and compared to healthy controls. DAOA patients with documented mental health challenges and those being followed by psychiatry were reported. RESULTS: Ninety seven (67 female, 69%) DAOA patients were included and compared to 70 controls (37 female, 53%). Mean treadmill time was significantly lower (9.5 vs 15.0 minutes; p = 0.02), supine HR was higher (92 vs 76 bpm; p < 0.001), peak HR (188 vs 196 bpm; p < 0.001) was lower, and % predicted HR achieved (92% vs 97%; p = 0.002) was lower in DAOA patients compared to controls. Supine (SBP) (116 vs 111 mmHg; p = 0.94) and diastolic blood pressure (DBP) (71 vs 67 mmHg; p = 0.14) were similar between DAOA patients and controls. Forty three of 97 (44%) had documented mental health challenges. There were no differences in DAOA patients with or without mental health challenges in treadmill time (9.2 vs 9.6 minutes; p > 0.05), supine HR (93 vs 90; p > 0.05), peak HR (187 vs 189; p > 0.05), and % predicted HR (91% vs 92%; p > 0.05); both groups were different than controls (all p ≤ 0.006). Twenty-eight of 97 (29%) DAOA patients were seen by psychiatry. Treadmill time SBP, DBP, supine, peak, and % predicted HR were similar between those seen by psychiatry and those who were not (all p > 0.05). CONCLUSION: DAOA patients have impaired exercise tolerance compared to healthy adolescents. Those with and without mental health challenges had similar exercise tolerance. At this time, it appears that while exercise tolerance is impaired in DAOA patients, it is not associated with mental health challenges.