Light on nonmotor symptoms in Parkinson's disease patients: The impact on quality of life.

Non-motor symptoms of Parkinson's disease contribute substantially to a reduction in health-related quality of life for patients and carers. Whilst some non-motor symptoms are dopamine-responsive, current treatment options for many are limited and often unsatisfactory. We report on early observations of non-motor symptoms in seven Parkinson's disease patients treated with daily transcranial red and near infrared photobiomodulation, over periods ranging from six to thirty-four months. Six of seven patients used home-made devices, including bucket light hats with unpulsed 630 nm-850 nm LED strips, and/or a commercial helmet delivering 40Hz-pulsed sequential 670 nm and 810 nm light. One patient used a home-made 660nm intra-nasal device. Progress was assessed by the subjects themselves, their spouse and attending clinicians. A range of non-motor symptoms appeared to improve during photobiomodulation treatment, especially fatigue, sleep, apathy, mood, anxiety, concentration/attention, anhedonia and olfaction. There were also improvements in motor signs and in the "sense of self". Photobiomodulation was well-tolerated, with no adverse effects and high patient compliance. In summary, daily photobiomodulation helped elicited and maintain improvements in otherwise difficult to treat symptoms.