Twelve people in South Australia volunteered to participate in a study on the effect of near-infrared light on people with Parkinson’s disease.
Dr Liebert presented the findings of a preliminary analysis of the data to the study participants, their families and members of Parkinson’s South Australia on Tuesday 9 September 2019.
The lead researcher was Dr Ann Liebert, University of Sydney, and her team included Dr Brian Bicknell, Australian Catholic University, Sharon Tilley, principal physiotherapist, Prof John Mitrofanis, University of Sydney and Prof Liisa Laakso, Griffith University. The study was supported by Parkinson’s South Australia.
The participants were separated into two groups of six:
Group A – started the 12-week treatment program straight away
Group B – had to wait 12 weeks, and then started their own 12-week program.
All participants were tested in a range of areas, using standardised testing methods and questionnaires. The testing covered:
- movement or motor symptoms
- non-movement or non-motor symptoms
- cognitive function
- a range of different laboratory tests
As well, the partners or carers were asked for their observations over the study period.
Each person was tested before starting and then retested at different intervals. This has generated a lot of data.
Each participant in each group, when treated with near-infrared light, started with a “full dose”, then over the 12 week period, the dose was gradually reduced. All bar one* of the participants then had a one week washout period followed by more testing.
All 12 participants are continuing light treatment and will be re-tested at 6 and 12 months. So there’s more data still to come.
- Each person experienced improvements in PD symptoms.
- Each person responded in a different time frame – some people made improvements very quickly, but others were slower to notice changes.
- Each person had a different ability to perceive changes within themselves. Improvements had been made in all participants, but a number of participants didn’t notice the improvements until these gains started to disappear when the dose was dropped.
- Non-movement symptoms were especially improved by red light. Two people regained their sense of smell, and two more were increasingly sure that their sense of smell had improved. Sleep improved in many, as did mood, speech articulation, voice quality, constipation, diarrhoea and pain.
Data awaiting analysis
There is still a lot of data to be analysed and is expected to be completed by later this year. This data includes:
- The observations made by carers
- Handwriting analysis – to assess fine motor skills
- Laboratory test results
- The full re-testing data
- The use of different light sources and locations (LED lights and laser lights on head, back of neck and on the abdomen).
Sydney clinical trial
The South Australian study has given valuable input to the design of Dr Liebert’s forthcoming Sydney trial, with protocol changes including:
- There will be no reduction in the red light dose over the 12 week treatment period
- The battery of tests will be expanded to include the sense of smell.
- The use of the Well Red Coronet trans-cranial light device.
Dr Liebert’s conclusions thus far
While we have to wait for the final and very detailed results, Dr Liebert concluded her presentation saying that:
- Use of red and near-infrared lights is showing itself to be a safe treatment.
- Evidence from this and other studies shows that red and near-infrared light improves a range of motor and non-motor Parkinson’s disease symptoms.
- The use of red and near infrared lights should be considered an adjunct to medication and exercise programs for people with Parkinson’s disease.
* The Group A participant who didn’t completely stop after the 12 week period continued to use lights – his symptoms had improved significantly, and he didn’t want to go back to how he had been. The results of another Group A participant were made difficult to interpret because of the effects of an unexpected and unrelated illness.