Dr. Roger T. Webb, at the University of Manchester in England, and associates obtained data regarding singleton births, infant mortality, and adult psychiatric hospitalizations from national registries in Denmark. They identified all cases of SIDS in the post-neonatal period between 1973 and 1998, and reported their findings in the Archives of General Psychiatry for November.
For a parental history of psychiatric hospitalization, for either fathers or mothers, the risk of SIDS was roughly doubled compared with the general population (relative risk 2.3 for each), the authors report. If both parents had been hospitalized, the relative risk was 6.9.
Among specific disorders, the greatest risk was associated with inpatient treatment for substance abuse, especially among mothers (maternal RR = 5.0; paternal RR = 2.5).
For affective disorders, corresponding RRs were 1.7 and 2.1.
Contrary to prior findings, schizophrenia-like disorders were no more liable to raise risk of SIDS than any other psychiatric disorders: RR 2.0 among women and 1.8 among men.
"When treating severe adult psychiatric illnesses, it is important to identify patients who already have or will soon have infants in their care," Dr. Webb's group writes. "To help raise parental awareness of modifiable risk factors, these especially vulnerable infants may be better protected if infants' pediatricians are informed of parents' mental illnesses."
Arch Gen Psychiatry 2007;64:1323-1330.
Reviewed by Ramaz Mitaishvili, MD