Data may link autism, vaccine

AUTISM UPDATE An alternative view of autism—its epidemiology, causes and treatment—was presented at Autism 2001: Place For New Medical Discoveries in Quebec City. The conference, under the honourary chairmanship of Dr. Victor Goldbloom, a pediatrician and former Quebec government minister, was organized by Autisme Québec et Chaudière-Appalaches in collaboration with Autisme et troubles envahissants du développement Montréal (ATEDM), two non-profit autism education and advocacy groups. Sponsors were the Quebec Ministry of Health and Social Services, and the Ministry of Research, Science and Techology, the Quebec Office of the Handicapped and Heritage Canada. Medical Post staff writer Susannah Benady files these reports.

Timing of MMR vaccination, autism outbreak questioned

By Susannah Benady May 8, 2001

QUEBEC CITY – Speakers at the conference here maintained statistics show a demonstrable link between an "explosion" in autism cases and introduction of the measles-mumps-rubella vaccine, even though California researchers contend the start of the upward swing predates the MMR vaccine.
   Physicians monitoring autism said the explosion could not be explained away by better diagnosis. The fact that the start of the increase did not coincide exactly with the date of introduction of the MMR did not exonerate the vaccine, they said.
   The number of children with autism and related developmental disorders has been rising at an alarming rate in many countries, including the U.K., the U.S. and Canada, said Dr. Bernard Rimland, director of the Autism Research Institute in San Diego, Calif.
   The U.K. reports a rate of one in 250 and the most recent figures from the U.S. Centres for Disease Control and Prevention show a rate as high as one in 150 for boys in the U.S.
   California, which maintains the world's most systematic database on autism and other developmental disabilities, reports an almost 10-fold increase in the prevalence of autism over a 20-year period, said Dr. Rimland.
   The number of autism cases being diagnosed in California since the introduction of the fouth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) tripled, to almost 2,000 cases in 1999 from 633 cases in 1994.
   There has been no corresponding increase in mental retardation, epilepsy or cerebral palsy, Dr. Rimland said.
   He criticized a recent paper in the Journal of the American Medical Association by physicians from the California department of health services concluding that the increase in autism predated the MMR vaccine. He offered a contrary interpretation as he presented a graph summarizing the California figures and statistics from a study done in North London (see page 21).
   The graph shows a jump in the California figures starting in 1977. The MMR vaccine was not introduced until 1979. Similarly, the increase in North London began a decade later, according to the graph, with numbers rising from 1984. The vaccine was not introduced there until 1987.
   However, Dr. Rimland said the graph shows the children's year of birth, not year of diagnosis, so the increase would inevitably have to predate the introduction of the vaccine.
   Also, he said the JAMA authors had not taken into account that when the vaccine was introduced it was given to older children as well as those under age two.
   Additionally, said Dr. Rimland, the authors did not account for the fact that the number ofvaccines being given to children generally doubled between 1980 and 1999.
   "This fact alone could be making them more susceptible to the MMR trigger," he said.
   Dr. Ed Yazbak, a Boston pediatric infectious disease specialist and former professor at Brown University, now conducting independent studies into autism, dismissed any suggestion that the increase in the statistics could be due to changes in the way the disorder is diagnosed.
   "It is the same individuals making the diagnosis according to the DSM-IV, which has very clear and strict criteria, as it was seven years ago when that standard was introduced," he said.
   "If it was to do with methods of diagnosis, we should have seen the huge increase in 1994, not now."