January 30, 2008 – The risk of suffering a stroke after a visit to a chiropractor would not be higher than after a visit to the doctor or to the emergency room.
This is what a Canadian study indicates1 covering stroke records from 1993 to 2002 in the province of Ontario.
In recent years, studies have raised suspicions about the risk of having a stroke of a rare type – following a rupture of the vertebral artery as a result of manipulation of the neck vertebrae by the chiropractor.
According to the researchers, the probability of such an incident occurring would be in the order of 1 in 5.85 million.
In the nine baseline years, Ontario reported 818 cases of stroke attributable to a ruptured vertebral artery, 80% preceded by headache or neck pain. In the 30 days preceding their stroke, 4% of patients had visited a chiropractor, compared to 53% who had consulted a doctor (for the same reason) in an office or in the emergency room.
Results: Whether patients visited a doctor or underwent cervical manipulation by a chiropractor, the risk of stroke was similar. However, for some unexplained reason, this risk was higher among those under 45, regardless of whether they consulted a doctor or a chiropractor.
According to the authors, the study confirms the existence of an association between cervical manipulation and the risk of suffering a stroke, while specifying that this risk “is not excessive”.
They insist that the cause and effect link has not been demonstrated: the stroke resulting from a dissection of the vertebral artery being preceded by headaches or in the neck, it is not yet known whether these symptoms are precursors of stroke or if they are a consequence of it.
Martin LaSalle – PasseportSanté.net
1. Cassidy JD, Boyle E, et al. Risk of Vertebrobasilar Stroke and Chiropractic Care: Results of a Population-Based Case-Control and Case-Crossover Study, Spine, Flight. 33, No 4, â € œNeck Pain Task Force Supplementâ € ??, S176-S183, February 15, 2008.
