Andrew Howard Evans

Background: Reducing nigrostriatal iron overload reduces neuronal loss in Parkinson's disease (PD) models. Objective: Examine the safety and efficacy of deferiprone in reducing motor disability progression in dopaminergic-treated and treatment-naïve patients with early-stage PD. Methods: Two phase II, multicenter studies, SKY and EMBARK, enrolled patients diagnosed with early PD (<3 years from screening). In SKY, patients on stable dopaminergic therapy were randomized 1:1 to one of four dosage (or placebo-matching) cohorts (300, 600, 900, 1200 mg twice daily [BID]) for 9 months. EMBARK enrolled patients on stable dopaminergic therapy or treatment-naïve patients and received 15 mg/kg BID. For both studies, the primary outcome was the change from baseline to month 9 in motor examination score (Movement Disorder Society-Unified Parkinson's Disease Rating Scale [MDS-UPDRS] Part III). ClinicalTrials.gov: NCT02728843; ANZCTR: ACTRN12617001578392. Results: Overall, 140 patients were randomized in SKY (28 per cohort). Thirty-six patients enrolled in EMBARK (27 dopaminergic-treated; 9 treatment-naïve). In the SKY study, all doses showed the same worsening as the placebo group, with the exception of the 600 mg dose, which was associated with non-significant reductions in MDS-UPDRS Part III least-squares mean (LSM) between baseline and 9 months (−2–8 points versus placebo). In EMBARK, LSM (SE) changes from baseline in MDS-UPDRS Part III were nonsignificant (–1.6 [1.7]) and significant (8.3 [3.9]) for dopaminergic-treated and treatment-naïve patients, respectively, the latter indicating disease worsening. Adverse events possibly related to deferiprone were reported in 35.7%–88.9% across all deferiprone groups vs. 42.9% for placebo. Conclusions: SKY and EMBARK studies indicate that deferiprone combined with L-dopa does not provide significant motor function benefit, while the absence of L-dopa treatment worsens symptoms.

INTRODUCTION Many patients with neurodegenerative disorders (ND) face diagnostic delay and misdiagnosis. We investigated blood and cerebrospinal fluid (CSF) neurofilament light chain (NfL) to distinguish ND from primary psychiatric disorders (ND), a common challenge in clinical settings. METHODS Plasma and CSF NfL levels were measured and compared between groups, adjusting for age, sex, weight. RESULTS 337 participants included: 136 ND, 77 PPD, 124 Controls. Plasma NfL was 2.5 fold elevated in ND compared to PPD and had strong diagnostic performance (area under the curve, AUC 0.86, 81%/85% specificity/sensitivity) that was comparable to CSF NfL (2 fold elevated, AUC 0.89, 95%/71% specificity/sensitivity). Diagnostic performance was especially strong in younger people (40-CONCLUSIONS This study adds important evidence for a simple blood-based biomarker to assist as a screening test for neurodegeneration and distinction from PPD, in clinical settings.

Background Levodopa remains the mainstay of treatment of Parkinson’s disease, however, over time motor fluctuations and levodopa-induced dyskinesia develop, requiring add-on therapies to control emerging symptoms. To date, however, there is no clear consensus in Australia, or elsewhere, at which dose of levodopa that add-on therapies should be considered. Objectives The purpose of this study was to examine the treatment patterns of patients with Parkinson’s disease in Australia, with particular focus on levodopa doses at the time of first add-on. Methods This was a retrospective, observational, non-interventional study of patients with Parkinson’s disease within the Australian Department of Human Services Pharmaceutical Benefits Scheme (PBS) 10% sample. Data on all reimbursed prescriptions (both general and concession), prescriber type and item code were extracted for patients who were dispensed at least three PBS reimbursed prescriptions for levodopa in the previous 12 months prescription from 1 January 2007 to 31 December 2021. Results 154 850 unique patients were included, of whom 42 330 (27%) commenced add-on therapy during the period. In the 12 months prior to add-on therapy, levodopa doses ranged from 100 mg/day to 1000 mg/day. The majority of patients were prescribed add-on therapy by a neurologist and approximately 40% of patients were prescribed levodopa doses of 600 mg/day or more prior to the first add-on therapy being initiated. Conclusions A large proportion of patients in Australia are managed with levodopa monotherapy doses that are considered high and many of these patients may benefit from the addition of add-on therapy to their regimen.

Parkinson’s disease (PD) is a chronic and progressive age-related neurodegenerative disease affecting up to 3% of the global population over 65 years of age. Currently, the underlying physiological aetiology of PD is unknown. However, the diagnosed disorder shares many common non-motor symptoms associated with ageing-related neurodegenerative disease progression, such as neuroinflammation, microglial activation, neuronal mitochondrial impairment, and chronic autonomic nervous system dysfunction. Clinical PD has been linked to many interrelated biological and molecular processes, such as escalating proinflammatory immune responses, mitochondrial impairment, lower adenosine triphosphate (ATP) availability, increasing release of neurotoxic reactive oxygen species (ROS), impaired blood brain barrier integrity, chronic activation of microglia, and damage to dopaminergic neurons consistently associated with motor and cognitive decline. Prodromal PD has also been associated with orthostatic hypotension and many other age-related impairments, such as sleep disruption, impaired gut microbiome, and constipation. Thus, this review aimed to present evidence linking mitochondrial dysfunction, including elevated oxidative stress, ROS, and impaired cellular energy production, with the overactivation and escalation of a microglial-mediated proinflammatory immune response as naturally occurring and damaging interlinked bidirectional and self-perpetuating cycles that share common pathological processes in ageing and PD. We propose that both chronic inflammation, microglial activation, and neuronal mitochondrial impairment should be considered as concurrently influencing each other along a continuum rather than as separate and isolated linear metabolic events that affect specific aspects of neural processing and brain function.

Objective: People with neuropsychiatric symptoms often experience delay in accurate diagnosis. Although cerebrospinal fluid neurofilament light (CSF NfL) shows promise in distinguishing neurodegenerative disorders (ND) from psychiatric disorders (PSY), its accuracy in a diagnostically challenging cohort longitudinally is unknown.Methods: We collected longitudinal diagnostic information (mean = 36 months) from patients assessed at a neuropsychiatry service, categorising diagnoses as ND/mild cognitive impairment/other neurological disorders (ND/MCI/other) and PSY. We pre-specified NfL > 582 pg/mL as indicative of ND/MCI/other.Results: Diagnostic category changed from initial to final diagnosis for 23% (49/212) of patients. NfL predicted the final diagnostic category for 92% (22/24) of these and predicted final diagnostic category overall (ND/MCI/other vs. PSY) in 88% (187/212), compared to 77% (163/212) with clinical assessment alone.Conclusions: CSF NfL improved diagnostic accuracy, with potential to have led to earlier, accurate diagnosis in a real-world setting using a pre-specified cut-off, adding weight to translation of NfL into clinical practice.

Background: Distinguishing a dementia syndrome from a primary psychiatric disease in younger patients can be challenging and may lead to diagnostic change over time. The aim of this study was to examine diagnostic stability in a cohort of patients with younger‐onset neurocognitive disorders.Method: We retrospectively reviewed records of patients that were admitted to our unit between 2000 and 2019, were followed‐up for ≥12 months and received a diagnosis of young onset dementia at any time point. Initial diagnosis included Alzheimer disease (AD)‐type dementia (n= 30), frontotemporal dementia (FTD) syndromes (n=44), vascular dementia (VaD, n=7), mild cognitive impairment (MCI, n= 10), primary psychiatric diseases (n=6) and other conditions such as Lewy Body Dementia (n=30).Result: In a total of n=127 patients, 49 (39%) changed their initial diagnoses during follow‐up. Behavioural variant FTD (bvFTD) was the least stable diagnosis, followed by dementia not otherwise specified and MCI. Compared to patients with a stable diagnosis, those who changed exhibited: a higher cognitive score at baseline, a longer follow‐up period, greater delay to final diagnosis, and no family history of dementia. Patients switching from a neurodegenerative to a psychiatric diagnosis more likely had a long psychiatric history, while those changing from a psychiatric to a neurodegenerative diagnosis had a recent manifestation of psychiatric symptoms.Conclusion: Misdiagnosis in younger patients with neurocognitive disorders is not uncommon, especially in cases of behavioural variant FTD. Late‐onset psychiatric symptoms may be the harbinger to a neurodegenerative disease. Close follow‐up and monitoring of these patients are necessary.

Chronic graft‐versus‐host disease (cGVHD) complicating allogeneic haemopoietic stem cell transplantation rarely involves the nervous system; oromandibular parafunction has not been previously reported. We describe five patients with cGVHD, presenting with bruxism, limitation of mouth opening, jaw locking, pain and masseter hypertrophy. Pathophysiological mechanisms are discussed. Targeted botulinum toxin injections were an effective treatment with minimal side‐effects.