To determine if co-morbid PTSD affects prevalence and severity of motor, nonmotor, and neuropsychiatric symptoms and age of onset of Parkinson's disease (PD) in veterans.

PTSD has been shown to increase risk of future PD. However, there is little data regarding whether PTSD affects PD symptoms.

Retrospective chart review of 176 veterans with Parkinson’s disease at the Jesse Brown VA Hospital in Chicago, Illinois, between 2009-2019. We reviewed age of symptom onset and diagnosis, presence of PTSD, presence of 35 motor and nonmotor symptoms, and H&Y scale. 

PTSD was associated with greater burden of neuropsychiatric symptoms (3.8 reported symptoms in PTSD group vs 2.3 in non-PTSD group, p-value (p) <0.00001) and sleep disturbances (1.5 symptoms vs 1.1, p= 0.03), and lower burden of motor symptoms (3 symptoms vs 3.5, p= 0.02). PTSD was associated with increased probability of depression (78% vs 55%, p=0.004), anxiety (79% vs 53%, p=0.002), apathy (71% vs 46%, p=0.012), panic attacks (59% vs 29%, p=0.01), aggression (79% vs 46%, p=0.001), pain (84% vs 68%, p=0.049), and bipolar disorder (11% vs 1.6%, p=0.006). Additionally, PTSD diagnosis led to decreased probability of falls (60% vs 79%, p=0.02), postural instability (31% vs 54%, p=0.02), drooling (38% vs 60%, p=0.04), constipation (58% vs 78%, p=0.02), nocturia (70% vs 88%, p=0.03), and cough (24% vs 43%, p=0.04). PTSD did not influence H&Y scales or age of onset.

As anticipated, PTSD patients have a greater burden of neuropsychiatric symptoms compared to patients without PTSD.  Surprisingly, there was an association between PTSD and decreased falls, postural instability, and burden of motor symptoms, in contrast to existing data demonstrating worse motor symptoms in patients with depression and anxiety.  Our data suggests that PTSD may predispose towards a less severe motor phenotype of PD with more neuropsychiatric and sleep disordered symptoms and fewer autonomic symptoms.