Optimizing Protein Patterns for Skeletal Muscle Preservation and Sleep in the Medical Management of Parkinson Disease

Status

Completed

Phases

Unknown

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05437640

Enrollment

Registered

2022-06-29

Start date

2022-10-01

Completion date

2024-11-25

Last updated

2026-06-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Parkinson Disease

Keywords

Parkinson Disease, Diet, Protein, Skeletal Muscle, Sleep

Brief summary

The purpose of this pilot study is to generate preliminary data on the impact of the dietary protein pattern on markers of skeletal muscle health and drug efficacy in Parkinson disease.

Detailed description

Parkinson's disease (PD) is a complex neurological disease that affects \ 6.1 million people worldwide - mostly older adults \>60 years. The most effective treatment for PD is dopaminergic therapy, particularly levodopa (Ldopa). People with PD have variable responses to Ldopa, including degrees of motor fluctuations (MF) throughout the day. The half-life of Ldopa is \ 1.5 h and therefore, dosage and timing are essential to mitigate MF. Ldopa is a large neutral amino acid (LNAA), and the bioavailability of Ldopa is compromised when simultaneously ingested with LNAA (e.g., leucine). Both Ldopa and LNAAs from food are absorbed through the same intestinal transporter, but LNAAs from food are preferentially absorbed by the enterocyte, limiting the bioavailability of Ldopa. Thus, the scientific community often recommends the protein-redistribution diet (PRD). With PRD, patients limit protein (\<10 g) at the desired time of medication efficacy (daytime) and meet their protein needs during the evening meal (\ 70+g). There are deleterious implications of the PRD for older adults with PD; consumption of \>30 g of protein, in a single meal, will not sufficiently increase muscle protein synthesis. Additionally, the impact of the PRD on skeletal muscle quality and function has not been determined, and it is unclear, based on prior studies, whether the PRD enhanced drug absorption. Therefore, the objective of this study is to address these gaps in knowledge. This study will quantify the effects of dietary protein pattern on skeletal muscle in PD; determine the effects of dietary protein pattern on sleep quality in PD. This study is an acute, 5-week, crossover intervention with PD participants randomly assigned to first adhere to either the PCD or PRD. Participants will receive diet prescriptions and meal plans for their respective diet, and outcome measures will be assessed at days 0, 14, 21, and 35.

Interventions

BEHAVIORALProtein Redistribution Diet

PD participants will be instructed by a Registered Dietitian to consume 10 grams or less of protein until their evening meal. They will then consume a high protein evening meal to meet their protein needs. They will receive one-on-one education and supportive materials to follow diet plan.

BEHAVIORALProtein Consistent Diet

PD participants will be instructed by a Registered Dietitian to consume 20-30 grams of protein per meal. They will receive one-on-one education and supportive materials to follow diet plan.

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

TREATMENT

Masking

SINGLE (Outcomes Assessor)

Masking description

Interpretation of blood biomarkers will be blinded to the intervention assignment.

Intervention model description

PD participants randomly assigned to first adhere to either the Protein Consistent Diet or Protein Redistribution Diet for 2 weeks. Participants will enter a 1-week washout period between the diets where they follow their typical diet and then follow the other diet prescription for 2 weeks.

Eligibility

Sex/Gender

ALL

Age

45 Years to 99 Years

Healthy volunteers

Inclusion criteria

* Clinical diagnosis of idiopathic PD for 5 or more years * 45 years or older * On a stable levodopa regimen for 3 or more months * Self-reported to experience motor fluctuations

Exclusion criteria

* Following a specific diet that would preclude participation * Renal disease * Deep brain stimulation * Known narcolepsy * Untreated sleep apnea * Any condition that, in the opinion of the investigator, will preclude the participant from successfully or safely completing study procedures

Design outcomes

Primary

Measure	Time frame	Description
Change in Markers of Skeletal Muscle Metabolism GDF15	Baseline to 5 weeks	Serum Growth Differentiation Factor 15 (GDF15)
Change in Markers of Skeletal Muscle Metabolism FGF21	Baseline to 5 weeks	Serum Fibroblast Growth Factor 21 (FGF21)
Change in Handgrip Strength	Baseline to 5 weeks	Handgrip strength assessed via digital dynamometer
Change in Sleep Efficiency	Baseline to 5 weeks	Sleep efficiency assessed via actigraphy
Change in Motor Symptoms	Baseline to 5 weeks	Motor symptoms assessed via the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part II. Part II ranges from 0-52 with higher scores indicating greater symptom severity.

Secondary

Measure	Time frame	Description
Change in Physical Activity	Baseline to 5 weeks	Physical activity assessed via actigraphy
Change in Total Parkinson Symptoms	Baseline to 5 weeks. Total score ranges from 0-260 with higher scores indicating greater symptom severity.	Parkinson-related symptoms assessed by total MDS-UPDRS score

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORChristine C Ferguson, PhD

University of Alabama at Birmingham

Participant flow

Participants by arm

Arm	Count
Total Participants All participants were scheduled to follow both dietary interventions. One participant withdrew during the washout phase. Enrolled n=12, final n=11	11
Total	11

Baseline characteristics

Characteristic	Total Participants
Age, Continuous	65 years
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	11 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants
Race (NIH/OMB) Asian	0 Participants
Race (NIH/OMB) Black or African American	0 Participants
Race (NIH/OMB) More than one race	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) White	11 Participants
Sex: Female, Male Female	4 Participants
Sex: Female, Male Male	7 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk
deaths Total, all-cause mortality	0 / 12	0 / 12
other Total, other adverse events	2 / 12	0 / 12
serious Total, serious adverse events	0 / 12	0 / 12