Re: Parental depression, maternal antidepressant use during pregnancy, and risk of autism spectrum disorders: population based case-control study
To the Editor:
Rai and colleagues conducted a case-control study on the association between antidepressant use during pregnancy and autism spectrum disorders in offspring with great number of samples (1). Compared with the past case-control study (2), there is an advantage of using variable on intellectual disability for their sub-analysis.
In contrast, Hviid and colleagues described no significant association between maternal use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy and autism spectrum disorder in the offspring by a cohort study over one decade of follow-up (3). In their sub-analysis, a significant association between maternal use of SSRIs before pregnancy and autism spectrum disorder was observed. They analyzed the data with enough number of events with use of SSRIs during pregnancy. I think that the quality of information on the use of SSRIs and diagnostic procedure of autism spectrum disorder are superior to those by Rai and colleagues.
Andrade reported the statistical problems of the above-quoted two case-control studies (4). Namely, they were summarized into type II error by the lack of statistical power and type I error by the lack of adequate adjustment by confounders. Although there are some limitations in a case-control study by Rai and colleagues, intellectual disability seems important to affect the relationship between antidepressant use during pregnancy and autism spectrum disorders in offspring. So I strongly recommend using "intellectual disability" as a key variable for cohort studies in the future.
1 Rai D, Lee BK, Dalman C, Golding J, Lewis G, Magnusson C. Parental depression, maternal antidepressant use during pregnancy, and risk of autism spectrum disorders: population based case-control study. BMJ 2013;346:f2059.
2 Croen LA, Grether JK, Yoshida CK, Odouli R, Hendrick V. Antidepressant use during pregnancy and childhood autism spectrum disorders. Arch Gen Psychiatry 2011;68:1104-12.
3 Hviid A, Melbye M, Pasternak B. Use of selective serotonin reuptake inhibitors during pregnancy and risk of autism. N Engl J Med 2013;369:2406-15.
4 Andrade C. Antidepressant use in pregnancy and risk of autism spectrum disorders: a critical examination of the evidence. J Clin Psychiatry 2013;74:940-1.
Competing interests: No competing interests