Is light therapy a potential treatment modality in Parkinson’s disease?
You can find out more about NPF's National Medical Director, Dr. Michael S. Okun, by also visiting the NPF Center of Excellence, University of Florida Center for Movement Disorders & Neurorestoration. Dr. Okun is also the author of the Amazon #1 Parkinson's Best Seller 10 Secrets to a Happier Life.
Recent research has indicated that there may be unexplored symptomatic benefits by using light therapy to treat Parkinson’s disease patients. This “light” approach is particularly appealing in Parkinson’s disease because patients commonly suffer from excessive daytime sleepiness, fatigue, sleep disorders, as well as depression—and all have been reported to potentially improve. In this month’s What’s Hot Column, we explore the scientific underpinnings of the brain’s natural sleep-wake cycle; called the circadian rhythm. The scientific term circadian rhythm is derived from the Latin words circa which means approximately, and diem which means day. The human sleep wake cycle has this been referred to as a circadian rhythm as it occurs everyday. Melatonin has been heavily implicated in the human sleep-wake cycle, and we will review both melantonin and light therapy, as potential symptomatic approaches for Parkinson’s disease.
Many investigators have focused on melatonin as an important chemical in the human sleep-wake circadian rhythm. Melatonin is manufactured in the center of the brain in a structure called the pineal gland. René Descartes referred to the pineal gland as the “seat of the soul.” Melatonin from the pineal gland can trigger sleepiness, and can also lower body temperature. The manufacture of melantonin is disrupted by exposure to light. Researchers have postulated that by intervening in the melatonin pathways by exposing people to bright light could have a therapeutic benefit.
Videnovic and colleagues at the National Parkinson Foundation Center of Excellence in Northwestern University recently explored blood melatonin tests sampled over 24 hours. The tests were designed to uncover some of the mysteries of fatigue, and the sleep-wake disturbances in Parkinson’s disease. The researchers studied twenty Parkinson’s patients and twenty control patients without Parkinson’s. Melatonin blood levels were checked every thirty minutes for twenty-four straight hours. Parkinson’s patients were observed not to secrete melatonin in a normal pattern. Parkinson’s disease patients in the study who suffered from excessive daytime sleepiness or fatigue had more dysfunction in the patterns of melatonin than those without excessive daytime sleepiness or fatigue. How long you had Parkinson’s disease, how severe your motor symptoms were, and what medications you were taking, were not related to the circadian rhythm. The author’s postulated that sleep-wake circadian function could be improved by timed exposure to bright light, and also potentially by exercise. There have been several other small studies that have also suggested Parkinson’s disease motor, as well as non-motor symptoms, may improve with light therapy.
In May 2014, at the 66th Annual Meeting of the American Academy of Neurology (AAN), Videnovic and colleagues presented another study on the preliminary results of light therapy for excessive daytime sleepiness or fatigue. There were thirty patients included with an average duration of disease of approximately seven years. The study intervention was bright light therapy (5000 lux) or dim red-light therapy (300 lux) delivered for two hours a day for fourteen days. The results did not reveal a difference between the groups, however a closer look at the scores in this small study revealed that the Epworth Excessive Sleepiness Scale improved by 2.3 points in the dim red light group, and 4.3 points in the bright light therapy group. Though these results were not robust, they suggested, at least the possibility, that light therapy could be optimized for better results in Parkinson’s disease. Some researchers have suggested that better penetrance of light therapy could be delivered through other techniques including deep brain electrodes, but this remains highly investigational and has only been attempted in animals.
If melatonin release is blocked by exposure to light, and exposing patients to light may improve Parkinson’s disease symptoms, why would patients intentionally take melatonin? Melatonin (N-acetyl-5-methoxy-tryptamine) is also an antioxidant. Neurodegenerative disorders such as Parkinson’s disease have been linked to oxidative damage and free radical generation, and some people believe that melatonin may help in blocking neurodegeneration. There are however no human studies to support the notion that melatonin slows or blocks neurodegeneration. Some patients also use melatonin for sleep issues, though again there are no large well-controlled studies to support this notion, and in many cases reports have surfaced that melatonin replacement may actually worsen sleep in Parkinson’s disease. I have personally listened to several patients who have tried melatonin, and reported worsening in sleep. If you decide to try melatonin (which is over the counter) for sleep, you should do it under the guidance of a physician. Until more data is published, we cannot make a recommendation as to the usefulness of melatonin replacement for sleep issues.
The bottom line is that there is accumulating evidence that melatonin is important to sleep and to excessive daytime sleepiness in Parkinson’s disease. Melatonin can possibly be powerfully modulated by light therapy and also possibly by exercise. Melatonin pills may not be the answer for many patients with Parkinson’s disease and could potentially worsen symptoms. More research will be needed to clarify how shining a light on Parkinson’s disease may provide a new option for patients, especially those with excessive daytime sleepiness.
1: Videnovic A, Noble C, Reid KJ, Peng J, Turek FW, Marconi A, Rademaker AW, Simuni T, Zadikoff C, Zee PC. Circadian melatonin rhythm and excessive daytime sleepiness in Parkinson disease. JAMA Neurol. 2014 Apr;71(4):463-9. doi: 10.1001/jamaneurol.2013.6239. PubMed PMID: 24566763.
2: Bolitho SJ, Naismith SL, Rajaratnam SM, Grunstein RR, Hodges JR, Terpening Z, Rogers N, Lewis SJ. Disturbances in melatonin secretion and circadian sleep-wake regulation in Parkinson disease. Sleep Med. 2014 Mar;15(3):342-7. doi: 10.1016/j.sleep.2013.10.016. Epub 2014 Jan 21. PubMed PMID: 24529544.
3: Cardinali DP, Pagano ES, Scacchi Bernasconi PA, Reynoso R, Scacchi P. Melatonin and mitochondrial dysfunction in the central nervous system. Horm Behav. 2013 Feb;63(2):322-30. doi: 10.1016/j.yhbeh.2012.02.020. Epub 2012 Feb 25. Review. PubMed PMID: 22391273.
4: Ortiz GG, Benítez-King GA, Rosales-Corral SA, Pacheco-Moisés FP,Velázquez-Brizuela IE. Cellular and biochemical actions of melatonin which protect against free radicals: role in neurodegenerative disorders. Curr Neuropharmacol. 2008 Sep;6(3):203-14. doi: 10.2174/157015908785777201. PubMed PMID: 19506721; PubMed Central PMCID: PMC2687933.
Posted: 6/2/2014 1:07:27 PM by
Browse current and archived What's Hot in PD? articles, the National Parkinson Foundation's monthly blog for people with Parkinson's written by our National Medical Director, Dr. Michael S. Okun.
Deep Brain Stimulation for Parkinson’s Disease: NPF Congratulates Mahlon DeLong and Alim-Louis Benabid and Looks to a Bright Future in Human Neural-Network Modulation
Everything You Need to Know About Medical Marijuana and Parkinson’s Disease
The End for Levodopa Phobia: New Study Shows Sinemet is a Safe Initial Therapy for Treatment of Parkinson's Disease
Is light therapy a potential treatment modality in Parkinson’s disease?
How does the most common genetic cause of Parkinson’s Disease (LRRK2) cause Parkinson’s disease and could it be used to help develop a better therapy?
An Update on DAT Scanning for Parkinson’s Disease Diagnosis
Could Northera (Droxidopa) Be an Alternative Treatment for Low Blood Pressure and Passing Out Symptoms?
The Dream of a Pill Free Existence and the Continuous Dopaminergic Pump for the Treatment of Parkinson's Disease
Should I take Inosine to Raise my Uric Acid Levels and Treat my Parkinson’s Disease?
Could Fungus and Mold be an Important Contributor to Parkinson’s Disease?
Pimavanserin and the Hope for a Better Drug for Hallucinations and Psychosis in Parkinson’s Disease
Halting of the Creatine Study
The Importance of Identifying and Treating Caregiver Strain
Putting Parkinson’s Disease Information into the Palm of Your Hand: Parkinson’s Enters the Smartphon
What Parkinson’s Disease Patients Need to Know about H. Pylori Gastrointestinal Infections
A2A Receptor Antagonists and Parkinson’s Disease Treatment
Another Setback for Trophic Factor Treatment in Parkinson's Disease
IPX066 and What Patients Really Want in New Carbidopa/Levodopa (Sinemet) Formulations
The Weather Forecast for Parkinson’s Disease Calls for Worldwide Economic Storm
Defeating the Barriers to Implementing Exercise Regimens in Parkinson’s Disease Patients
When should you start medication therapy for Parkinson’s disease?
Neurologist Care Reduces Hospitalizations in Parkinson's Disease
A Victory in Court for Parkinson's Disease Patients who Require Ongoing Rehabilitative Therapies
Given the recent FDA announcement about Mirapex (pramipexole), should I be worried about dopamine agonists?
What about the new Parkinson’s Disease Vaccine? What should I know?
Caffeine as a Potential Treatment for Parkinson’s Disease
Time to Consider GPi DBS for Parkinson’s Disease: A Shift in the Practice of Patient Selection for DBS
A New Treatment for Parkinson’s Disease-Related Constipation
Too Many Pills: Improving Delivery Systems for Parkinson’s Disease Drugs
Measuring Quality and Assessing Depression in Parkinson's Disease
Watch out for Unexpected Obstacles if You Use a Cueing Strategy to Break Freezing of Gait in Parkinson’s Disease
Pill Color, Generic Medications and Insurance Issues: Important Medication-Related Tips for the Parkinson’s Disease Patient
Are Blood Tests for Parkinson’s Disease on the Horizon?
Placing Stem Cells in Animal Models of Parkinson’s Disease: Another Important Step
Important News for the Parkinson’s Disease Community: More Evidence that Sinemet and Madopar are Not Toxic and do Not Accelerate Disease Progression
The Case for All Parkinson’s Disease Patients to be Co-managed by a Primary Care-Neurologist Team
Scientists say Research on Brain Proteins Involved in Parkinson’s Disease is “Shaping” Up
Who Actually Takes Care of Most of the Parkinson’s Patients Worldwide: The Need for Education and the Parkinson’s Toolkit
If you are Dizzy or Passing Out, it could be Your Parkinson’s Disease or Parkinson’s Disease Medications
How Will Group Visits for Parkinson’s Disease Fit into the Future of Parkinson’s Disease Care?
Why Patients Should be Wary of Chelation Therapy for Parkinson’s Disease
Opening the Door to Gene Therapy in Parkinson’s Disease: The Need for Refinement of the Technology and Approach
Does it Matter if I Can’t Get Brand Sinemet?
Should I get a DaTscan or PET scan to confirm my diagnosis of Parkinson’s disease?
A Critical Reappraisal of the Worst Drugs in Parkinson’s Disease
Environmental Risks for PD: Manganese, Welding, Mining, and Parkinsonism
Calling for the FDA to Revise the Eight Sinemet a Day Rule
Dry Cleaning Solvents and Potential Environmental Risks for Developing Parkinson’s Disease
Maintaining the Balance: Why Parkinson’s Disease Patients Need to Understand Drug Recalls, Withdrawals, and Safety Alerts
Shining a Light on Parkinson’s Disease: Optogenetics Has a Bright Future in Research
Poor Medication Management of Parkinson's Disease During Hospital Admissions: Patients and Families Can Improve Their Hospital-Based Management
Why Are Patches and Continuous Release Technology a Big Deal to Parkinson's?
Is the PD SURG Trial Another Surge Forward for DBS Therapy?
Cycling in PD in Those Who Can’t Walk: Is it Possible?
New iPS Stem Cells for PD: What Does it Mean?
Time for Comprehensive Care Networks for PD
Is Parkinson's Disease a Prion Disease?
Parkinson's Disease Linked to Gaucher's Disease
Brain Cells Keep Time Stamps: Implications for Parkinson's Disease Therapies
Is it Safe to Have an MRI with a DBS in Place?
Take Care of Your Bones as They Are Affected in Parkinson's Disease (Even in Men)
Is it Time to Start Paying Attention to Pain Symptoms in Parkinson's Disease Patients?
Glutathione Fails to Demonstrate Significant Improvement in PD Symptoms
Keeping an Eye on Trials Important to the Parkinson's Disease Patient
Increased Risk of Melanoma in Parkinson's Disease
Finally a DBS Expert Consensus Statement Aimed at Their True Customers: The Patients
Pesticides and Environmental Exposure in Parkinson's disease: Should We Stay Away From the Stink Truck?
Is Exercise Effective Treatment and Protection Against PD?
Why are Transplant Trials Struggling to Succeed in the Treatment of PD?
Are Monoamine Oxidase Inhibitors Disease Modifying or Neuroprotective in PD?
Update on Gene Therapy for Parkinson's Disease