Brainstem Serotonin in Sudden Infant Death Syndrome—Reply

In Reply: Dr Mage and Mr Kollander express concern over the generalizability of our study results and whether they apply beyond the small cohort sampled. Our sample consisted of all consecutive autopsies of unexpected infant deaths in San Diego from 2004 through 2008 for which a study technician was available and the postmortem interval was less than 30 hours to ensure stability of the neurochemical measurements. The study diagnoses for all of the cases were made in a uniform fashion based on standardized death scene evaluations and autopsies. The question is then whether SIDS or non-SIDS control cases in San Diego are different from those elsewhere. Some SIDS risk factors were not representative, in particular the high prevalence of Hispanic ethnicity and lower prevalence of African American race in our population. However, the key question is whether there is reason to believe that levels of serotonin in the brainstems of SIDS or non-SIDS infants in San Diego would be different than in infants elsewhere. We do not have any reason to believe this is the case, although future confirmation by other groups is needed.