Yikes! It’s bad enough taking medication that can have unpleasant side effects (even if I do seem to be very good at avoiding them thus far*), without considering brain surgery. Yet brain surgery is widely accepted as a treatment for later stage Parkinson’s. The main reason that I haven’t mentioned it thus far is that it isn’t relevant to my own experience. And it still isn’t; I’m not planning on surgery any time soon. But there is talk of DBS in early stage PD being a disease-modifying strategy…
I did meet a lady at the CPT meeting in London who told me that she had had DBS and that it worked wonders for her. She had no symptoms whatsoever, she said. She thought it was a marvellous treatment and that it should be promoted more. She was, it has to be said, a good advert for the procedure. But I don’t know what stage she would have been at when she went under the knife.
However, DBS is not usually performed during the early stages of the disease, probably in part because of the risks. Surgical techniques are improving all the time, and those risks are getting smaller, but they still exist. Why expose yourself to the risk of stroke or other brain damage when you’re mostly getting on fine?
But. Apparently, there is some suggestion that early recourse to DBS can slow the progression of the condition. No symptoms plus slower progression? Almost sounds like a win-win situation…
Researchers in Nashville, Tenessee have initialised a study on DBS in early stage PD. It’s early days (and so any protective effect is unlikely to be visible), but so far their subjects seem to be doing well. The abstract says:
Background Recent evidence suggests that deep brain stimulation of the subthalamic nucleus (STN-DBS) may have a disease modifying effect in early Parkinson’s disease (PD). A randomised, prospective study is underway to determine whether STN-DBS in early PD is safe and tolerable.
Conclusions The perioperative adverse events in this trial of subjects with early stage PD are comparable with those reported for STN-DBS in advanced PD. The active contact position used in early PD is not significantly different from that used in late stage disease. This is the first report of the operative experience from a randomised, surgical versus best medical therapy trial for the early treatment of PD.
“Deep brain stimulation in early stage Parkinson’s disease: operative experience from a prospective randomised clinical trial”
Elyne Kahn,Pierre-Francois D’Haese, Benoit Dawant, Laura Allen, Chris Kao, P David Charles, Peter Konrad.
Published in J Neurol Neurosurg Psychiatry 2012 Feb. Vol 18 (2); 164-170
That got me wondering about the “recent evidence” that suggests a “disease modifying effect”. I found a report (dating from March 2010) on the Michael J Fox Foundation’s Web site of a study by the same group that began in 2006. David Charles is quoted as saying:
“DBS has proven beneficial in the advanced stages of Parkinson’s, and we believe that if the therapy were applied very early, it might modify the disease progression and the development of disability. […] The big question — could DBS modify disease progression — can’t be answered until we do a large-scale trial.”
When I searched for further evidence, it all seemed to come bck to this one group. There was an “Illustrative Case” published online in September last year in which Charles et al concluded that, for the gentleman under discussion, there was an improvement:
Results: The subject showed a lower STN to substantia nigra ratio of neuronal activity than advanced PD patients, and higher firing rate than non-PD patients. The subject’s total UPDRS and UPDRS-III scores improved during the two-year follow-up, while his OFF UPDRS-III score and levodopa equivalent daily dose increased. Quality of life, verbal fluency, and verbal learning improved. He did not experience any serious adverse events.
“Deep Brain Stimulation for Early-Stage Parkinson’s Disease: An Illustrative Case”
Chandler E. Gill BS; Laura A. Allen BE; Peter E. Konrad MD, PhD; Thomas L. Davis MD; Mark J. Bliton PhD; Stuart G. Finder PhD; Michael G. Tramontana PhD; C. Chris Kao MD, PhD; Michael S. Remple PhD; Courtney H. Bradenham MD; P. David Charles MD
Published in Neuromodulation: Technology at the Neural Interface, Volume 14, Issue 6, pages 515–522, November/December 2011
I can’t help but wonder why these are the only people interested in applying the procedure at such an early stage. No doubt there is a financial element – this sort of procedure must be frighteningly expensive – and perhaps there is an ethical element (going back to the “if it isn’t all that broken yet, why try to fix it if you run the risk of breaking it even worse” idea alluded to above). But if there is that much promise… why aren’t we hearing more about it? It’s got a wonderfully media-friendly potential for controversy, too.
Maybe I just missed the coverage until now.
* The only side effect that I can recall having to a drug was being violently sick when I had the mild painkiller entonox (also known as gas and air) during labour for my first child. The second child arrived quite promptly once labour had started; we were discussing pain relief when she decided that enough was enough, she was coming out!