Impact of depressive symptoms on self-perceived severity of autonomic dysfunction in multiple system atrophy: relevance for patient-reported outcomes in clinical trials

Purpose: To assess the relationship between depressive symptoms and self-perceived severity of autonomic dysfunction in patients with multiple system atrophy (MSA). Methods: Cross-sectional evaluation of patients with MSA who underwent autonomic testing, Unified MSA Rating Scale (UMSARS)-1 and -2, rating of the presence and severity of depressive symptoms (Zung scale), quality of life (SF-36), body vigilance, anxiety (Spielberger’s anxiety scale), severity of autonomic dysfunction with the Composite Autonomic Symptoms Score (COMPASS-31), and severity of orthostatic hypotension (OH) symptoms with the Orthostatic Hypotension Questionnaire (OHQ). Results: Fifty-eight patients (32 women) with probable MSA (aged 61.8 ± 8.6 years; disease duration 4.3 ± 2.1 years) were studied. Forty patients (69%) had symptoms of depression in the Zung scale. Age, disease duration, and motor disability were similar in those with and without symptoms of depression. Despite a similar orthostatic blood pressure fall, the severity of orthostatic symptoms was higher in patients with symptoms of depression (p = 0.004). Depression scores were associated with higher burden of autonomic symptoms (R = 0.401, p = 0.02), specifically with the COMPASS-31 items related to orthostatic intolerance (R = 0.337, p = 0.045), and with the OHQ (R = 0.529; p < 0.001). A multivariable regression model including age, sex, UMSARS, and drop in systolic blood pressure upon head-up tilt as covariates showed that the burden of depressive symptoms was independently associated with the OHQ score: for every 1-unit increase in the Zung depression score, there was a 1.181-point increase in the total OHQ score. Conclusions: In patients with MSA, depressive symptoms worsen the perceived severity of autonomic symptoms in general and orthostatic hypotension in particular. Our findings have implications for clinical trial design.