Hot topics in Parkinson’s disease research from AAN Virtual 2022

Making the diagnosis

Significant overlap between the clinical features of Parkinson’s disease (PD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) can make diagnosis a challenge. Olszewska and colleagues¹ reported their novel Real-Time Quaking-induced Conversion (RT-QuIC) protocol that enables rapid detection of alpha-synuclein in cerebrospinal fluid using a minimally invasive cervical skin biopsy. Combining the results with serum neurofilament light chain measurement achieved 100% sensitivity/100% specificity in distinguishing MSA from PD and 100% sensitivity/93% specificity for MSA versus PD/PSP/healthy controls.

Combining the results achieved 100% sensitivity/100% specificity in distinguishing MSA from PD

Could smell therapy improve apathy?

In Alzheimer’s disease and mild cognitive impairment there appears to be an association between olfactory dysfunction and apathy, which share anatomical pathways, suggesting smell therapy as a potential therapeutic approach for apathy. Nunez and colleagues² were interested if there was a similar relationship in PD, using data from 486 patients with PD followed for 5 years in the Parkinson’s Progression Markers Initiative Study. They found no association between apathy and olfactory dysfunction, no difference in olfaction between patients with and without apathy, and no difference between patients with and without olfactory dysfunction in their time to develop apathy (all p>0.05). This highlights the clinical heterogeneity in neurodegenerative disorders.

They found no association between apathy and olfactory dysfunction

Training the mind and the gait

Shaji and colleagues³ were interested in the use of mindfulness-based interventions (MBI) for newly diagnosed patients with PD. They enrolled 25 patients for an 8-week program, with assessment using a number of measurement instruments at baseline, 8 weeks and 3 months. There was significant improvement in both motor and neuropsychiatric deficits, with increased mindfulness and emotional wellbeing and reduced stress. These were seen immediately following the MBI and maintained at 3-month follow-up.

Significant improvement in both motor and neuropsychiatric deficits

Gait training is an important part of rehabilitation for patients with PD. Amin et al.⁴ studied factors influencing the response to a 10-week gait training program in 19 patients. Greater improvements in gait speed in unadjusted and age-adjusted models were independently associated with better baseline memory performance and lower MDS-UPDRS Part III scores, but not with baseline executive function. The authors suggested that memory may be more important than other cognitive domains in effective gait rehabilitation, and degree of motor involvement will also influence the response.

Memory may be more important than other cognitive domains in effective gait rehabilitation

It’s a team game

Specialized physiotherapy (PT) reduces complications and healthcare costs for patients with PD. Talebi and colleagues⁵ looked at whether this was also true for specialized occupational therapy (OT) and speech and language therapy (SLT). Their retrospective observational study of 51,464 patients with PD used healthcare expenditure data from the Netherlands. The authors confirmed the inverse association between specialized PT and the incidence of complications and demonstrated this was also true for specialized OT. A similar trend for specialized SLT was not statistically significant.

Inverse association between specialized PT and OT and the incidence of complications