Serotonin Defects Said to Underlie SIDS

October 31, 2006

BOSTON -- The brain of babies who die of sudden infant death syndrome (SIDS) have multiple serotonin system defects, and this appears to pin down an underlying fatal susceptibility in these children, according to researchers here.

BOSTON, Oct. 31 -- The brain's serotonin system has multiple defects in babies who die of sudden infant death syndrome (SIDS), according to researchers here.

The finding appears to pin down the underlying vulnerability that makes some infants susceptible to SIDS when they encounter some outside stress, while others are not, reported David Paterson, Ph.D., of Boston Children's Hospital and Harvard Medical School, and colleagues, in the Nov. 1 issue of the Journal of the American Medical Association.

"We provide strong evidence that SIDS is a biological problem, and that the brainstem serotonin system is a good place to focus continued research efforts," Dr. Paterson said.

Dr. Paterson and colleagues examined tissue samples from the brainstems of 31 SIDS children who died in the San Diego area between 1997 and 2005, comparing them with samples from 10 infants who died of other acute causes in the same region and time period.

They found significant differences in the number and density of serotonergic neurons in the medulla oblongata, as well as in the density of one of the major serotonin receptors. Specifically, compared to controls, SIDS babies:

  • Had a significantly higher serotonergic neuron count, at P