NEW YORK (Reuters Health) - Young children of mothers with chronic anxiety and depression are at increased risk of developing asthma, findings from a long-term, population-based study indicate.
Small studies have identified postpartum depression as a risk factor for asthma in children who are genetically predisposed to asthma, Dr. Anita L. Kozyrskyj, from the University of Manitoba in Winnipeg, and her associates note. Whether this is true for children who are not at high-risk for asthma, but who do have mothers with psychiatric illnesses other than postpartum depression is not known.
The investigators determined the prevalence of asthma at age 7 years among 13,907 children born in Manitoba in 1995, using medical records maintained by the Manitoba Health Services Insurance Plan. Maternal distress was established on the basis of physician visits, hospitalizations, or prescription medications for depression or anxiety.
The records showed that 2,625 children were exposed to maternal distress. Six percent were exposed during the first year; 5 percent had additional short-term exposures or at least one additional episode between year 1 and year 5; and 9 percent had long-term exposure, defined as episodes in year 1, year 1 to 5, and year 5 to year 7.
The prevalence of asthma in the children increased with the extent of exposure to their mother's psychiatric problems, from 7.0 percent among those exposed only during the first year, to 7.4 percent among those exposed to at least one further time; and 9.7 percent of those exposed long-term.
The association between asthma in the children and exposure during the first two time periods was not statistically significant, Kozyrskyj and colleagues report.
However, exposure to maternal distress for the longer period was independently associated with childhood asthma, even after other asthma risk factors were considered. The asthma risk increased by 25 percent in this group compared with the other two groups.
"Our population-based findings hint at obvious social, clinical, and public policy indications, particularly for new parents," Kozyrskyj and associates maintain. However, additional studies are required before recommendations can be made regarding the early intervention of children with mothers with depression or anxiety disorders to avoid the development of asthma.
SOURCE: American Journal of Respiratory and Critical Care Medicine, January 2008.
