Caffeine for Excessive Daytime Somnolence in Parkinson's Disease

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00459420
Recruitment Status : Completed
First Posted : April 12, 2007
Last Update Posted : April 16, 2015
Canadian Institutes of Health Research (CIHR)
University of Toronto
Information provided by (Responsible Party):
Ron Postuma, McGill University Health Center

Brief Summary:
Many patients with Parkinson's disease (PD) have sleep problems, including excessive sleepiness during the day. This is probably due to degeneration of sleep-regulating areas in the brain. At present, the only treatment for sleepiness in PD is modafinil, which is expensive and only partially effective. There is another potential treatment for sleepiness that is used worldwide, is inexpensive, well tolerated and safe - namely, caffeine. There have also been suggestions that caffeine may slow the progression of degeneration in PD, since coffee non-drinkers are at higher risk of developing PD. PD patients, even with severe sleepiness often do not use caffeine. It is unclear whether this is because their PD makes their sleepiness unresponsive to caffeine, because they cannot tolerate it, or whether this reflects their lifelong habit of non-use. This proposal outlines a trial in which patients with excessive sleepiness will be given caffeine or placebo (no therapy) in a blinded fashion. In this way, the effect of caffeine on sleepiness and motor symptoms can be directly analyzed. In addition, these findings can be used to test the tolerability of caffeine, to help plan a larger-scale study testing whether caffeine can slow the progression of PD

Condition or disease Intervention/treatment Phase
Parkinson's Disease Excessive Daytime Somnolence Drug: Caffeine 100-200 mg BID Drug: placebo Phase 2 Phase 3

Detailed Description:

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by motor disability and many disabling non-motor symptoms. Excessive daytime somnolence (EDS) is found in up to 50% of patients with PD, and can cause considerable impairment of quality of life. At present, the only proven treatment for EDS in PD is modafinil, an alerting agent with an unknown mechanism of action. However, modafinil is only moderately effective and is very expensive. Caffeine is a very well tolerated and inexpensive alerting agent that is used worldwide, but very few patients with PD use it as therapy for EDS. It is unclear whether this is because it does not help EDS in PD, has side effects, or simply has not been considered because of lifelong patterns of non-use.

If caffeine can be demonstrated as an effective agent for EDS in PD, it will likely become the first-line agent for EDS. This will result in considerable cost savings for patients and health care payers, as well as potentially helping those who cannot tolerate, do not respond to, or cannot afford modafinil.

Another compelling question of interest to patients with PD is whether caffeine may be neuroprotective. Despite intensive research, no treatment has been found that can slow the progression of neurodegeneration in PD. Recently numerous epidemiologic studies have linked lifelong use of caffeine to a lower risk of PD. Although the mechanism for this finding is unclear, supporting evidence from animal models suggests that a true neuroprotective benefit of caffeine is a strong possibility. Alternatively, caffeine could have a benefit on motor manifestations of PD, which would prevent diagnosis of PD. Any finding of a symptomatic benefit of caffeine on motor manifestations of PD will have obvious and important implications for treatment of persons affected with PD and for planning of neuroprotective trials. Any finding of a neuroprotective benefit of caffeine will almost certainly result in its immediate widespread use in PD, with profound implications for patient care.

The present proposal is for a double blind randomized placebo controlled crossover trial that will answer three important questions in PD: is caffeine useful for the treatment of EDS in patients with PD? does caffeine have any symptomatic effect on the motor manifestations of PD? and, does caffeine have an acceptable tolerability and side effect profile that will allow planning of an eventual neuroprotective trial? Patients with PD who have EDS with an Epworth sleepiness scale of >10 will be randomized to caffeine therapy (100 mg twice per day for three weeks, then 200 mg twice per day for three weeks) or placebo. A final assessment will be performed after a 4-week washout. A total of 52 patients will be randomized over a two-year period. The primary outcome measure will be the change in Epworth sleepiness scale between patients receiving caffeine versus placebo. Secondary outcome measures will include other sleep scales, tolerability measures, and measures of motor function and overall quality of life. After tests to assess normal distribution, analysis will be with two-sample t-test.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 58 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Caffeine for Excessive Daytime Somnolence in Parkinson's Disease
Study Start Date : April 2007
Actual Primary Completion Date : July 2011
Actual Study Completion Date : July 2011

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Placebo Comparator: Placebo Drug: placebo

Experimental: Caffeine Drug: Caffeine 100-200 mg BID
Caffeine 100 mg BID for three weeks, then 200 mg BID for three weeks, then 100 mg BID for 1 week, then placebo

Primary Outcome Measures :
  1. Change in Epworth Sleepiness Scale [ Time Frame: 3 weeks ]

Secondary Outcome Measures :
  1. Unified Parkinson Disease Rating Scale [ Time Frame: 3 weeks ]
  2. Clinical Global Impression of Change [ Time Frame: 3 weeks ]
  3. Pittsburgh Sleep Quality Index [ Time Frame: 3 weeks ]
  4. Fatigue Severity Scale [ Time Frame: 3 weeks ]
  5. Stanford Sleep Scale [ Time Frame: 3 weeks ]
  6. PDQ-39 [ Time Frame: 3 weeks ]
  7. SF-36 [ Time Frame: 3 weeks ]
  8. Tolerability of Caffeine [ Time Frame: 3 weeks ]
  9. Beck Depression Inventory [ Time Frame: 3 weeks ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • A diagnosis of idiopathic PD
  • Excessive daytime somnolence (defined as an Epworth sleepiness scale score of >10).

Exclusion Criteria:

  • Estimated daily caffeine intake of more than 200 mg per day
  • Active peptic ulcer disease
  • Supraventricular cardiac arrhythmia (such as atrial fibrillation or atrial flutter)
  • Uncontrolled hypertension - defined as systolic bp >170 or diastolic bp >110 on two consecutive readings
  • EDS is caused by sleep apnea, restless legs syndrome, narcolepsy, shift work, or sleep promoting agents.
  • Current use of prescribed alerting agents such as modafinil and methylphenidate
  • Pre-menopausal women who are not using effective methods of birth control
  • Dementia, defined as MMSE <24/30 and ADL impairment secondary to cognitive loss, or inability to understand consent process
  • Depression, as defined by a Beck Depression Inventory score of >15.
  • Changes to antiparkinsonian medication in the last 3 months, or changes to antiparkinsonian medication are anticipated during the study protocol.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00459420

Canada, Ontario
Toronto Western Hospital
Toronto, Ontario, Canada
Canada, Quebec
Montreal General Hospital
Montreal, Quebec, Canada, H3G 1A4
Sponsors and Collaborators
Ron Postuma
Canadian Institutes of Health Research (CIHR)
University of Toronto
Principal Investigator: Ron Postuma, MD, MSc Montreal General Hospital

Responsible Party: Ron Postuma, Neurologist, McGill University Health Center Identifier: NCT00459420     History of Changes
Other Study ID Numbers: GEN-06-68
First Posted: April 12, 2007    Key Record Dates
Last Update Posted: April 16, 2015
Last Verified: April 2015

Keywords provided by Ron Postuma, McGill University Health Center:
Parkinson's disease
Excessive Daytime Somnolence

Additional relevant MeSH terms:
Parkinson Disease
Parkinsonian Disorders
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases
Central Nervous System Stimulants
Physiological Effects of Drugs
Phosphodiesterase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Purinergic P1 Receptor Antagonists
Purinergic Antagonists
Purinergic Agents
Neurotransmitter Agents