What Are Common Catalysts of Early Morning OFF Periods in Patients With Parkinson Disease?

Seven symptoms were identified as most predictive of early morning OFF periods (EMO) in patients with Parkinson disease, according to study findings published today in Translational Neurodegeneration.

Although OFF periods have the potential to affect quality of life (QOL) for both patients with PD (PwP) and their respective caregivers, study authors highlight the paucity of data examining EMO, particularly among Asian populations.

“Lack of awareness, limited consultation time, and insufficient communication between clinicians and patients often preclude timely recognition of EMO in routine clinical visits,” said the study authors.

Due to the financial and health impacts related to EMO, researchers noted the crucial need to form a convenient and pragmatic screening tool. They aimed to create a self-assessment instrument that characterizes clinical features of EMO in a Chinese population.

The study included 942 PwP admitted to 55 clinic centers for movement disorders across China from June 2018 to May 2019. Participants were examined via stepwise logistic regression analyses that determined potential risk factors and the most predictive symptoms of EMO.

Based on regression analyses, researchers constructed a 7-question scale for EMO screening. To examine diagnostic accuracy of the scale, researchers utilized the area under the receiver operative characteristic curve (AUROC). They also examined the scale for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the optimal cutoff point.

From the study cohort, EMO occurred in 49.2% of PwP across all disease stages. Notably, 7 symptoms were identified as most predictive of EMO:

• Bradykinesia or rigidity
• Excessive sweating or salivation
• Difficulty in turning on or getting out of bed
• Muscle cramp
• Fatigue or sleepiness
• Frozen state or freezing gait
• Tremor

The scale was found to be of good discrimination, according to the study authors, with a relatively high AUROC of 0.83 and relatively high sensitivity of 75.7%. The scale additionally exhibited a specificity of 77.5%, PPV of 76.5%, and NPV of 76.7%.

Researchers also examined potential independent risk factors that increased risk of EMO, which were found to be nonideal nighttime sleep, long PD duration, advanced Hoehn-Yahr stages, posture instability gait difficulty-dominant or mixed subtypes, and high levodopa dose. Of PwP experiencing EMO, 87% (odds ratio, 1.87; 95% CI, 1.07-3.32) were found to be at greater risk of experiencing functional dependency in daily living compared with those not experiencing EMO.

“Following successful external validation, this EMO scale is expected to facilitate earlier detection of EMO, allow timely therapy modification, enable optimal symptomatic control, [and] thereby contribute to all-day management and QOL improvement,” the study authors concluded.

Reference

Han C, Mao W, An J, et al. Early morning off in patients with Parkinson’s disease: a Chinese nationwide study and a 7-question screening scale. Transl Neurodegener. Published online July 6, 2020. doi:10.1186/s40035-020-00208-z