Question
Please read the following abstract (adapted from O'Reilly EJ, Mirzaei F, Forman MR, Ascherio A. Diethylstilbestrol exposure in utero and depression in women. Am J Epidemiol. 2010;171(8):876-82) and answer the corresponding questions:
Background: Diethylstilbestrol (DES) is an estrogenic endocrine disruptor with long-term health effects, possibly including depression, following exposure in utero.
Methods: The association between in utero DES exposure and depression was assessed among participants in the Nurses' Health Study II who were followed from 1995 to 2005.
Results: 76,240 women were eligible for inclusion in this study. DES exposure was reported by 1,612 (2.2%) women. Incident depression (first use of antidepressants among women who also reported depressive symptoms) during follow-up was reported by 19.7% of women exposed to DES and 15.9% of women unexposed to DES (OR = 1.41, 95% CI: 1.22, 1.63).
Conclusions: These results suggest that the neurophysiologic effects of in utero exposure to DES could lead to an increased risk of depression in adult life.
What is the study design? What is the study population?
Interpret “OR = 1.41.” Are these exposure odds or disease odds? Why?
What would have been a more appropriate relative measure for the investigators to calculate given the type of data collected?
Under what conditions does the Odds Ratio approximate this measure?
Source: 250A problem bank week 5
