Antidepressants in pregnancy: applying causal epidemiological methods to understand service-use outcomes in women and long-term neurodevelopmental outcomes in exposed children

Background

Antidepressants are commonly prescribed during pregnancy, despite a lack of evidence from randomised trials on the benefits or risks. Some studies have reported associations of antidepressants during pregnancy with adverse offspring neurodevelopment, but whether or not such associations are causal is unclear.

Objectives

To study the associations of antidepressants for depression in pregnancy with outcomes using multiple methods to strengthen causal inference.

Design

This was an observational cohort design using multiple methods to strengthen causal inference, including multivariable regression, propensity score matching, instrumental variable analysis, negative control exposures, comparison across indications and exposure discordant pregnancies analysis.

Setting

This took place in UK general practice.

Participants

Participants were pregnant women with depression.

Interventions

The interventions were initiation of antidepressants in pregnancy compared with no initiation, and continuation of antidepressants in pregnancy compared with discontinuation.

Main outcome measures

The maternal outcome measures were the use of primary care and secondary mental health services during pregnancy, and during four 6-month follow-up periods up to 24 months after pregnancy, and antidepressant prescription status 24 months following pregnancy. The child outcome measures were diagnosis of autism, diagnosis of attention deficit hyperactivity disorder and intellectual disability.

Data sources

UK Clinical Practice Research Datalink.

Results

Data on 80,103 pregnancies were used to study maternal primary care outcomes and were linked to 34,274 children with at least 4-year follow-up for neurodevelopmental outcomes. Women who initiated or continued antidepressants during pregnancy were more likely to have contact with primary and secondary health-care services during and after pregnancy and more likely to be prescribed an antidepressant 2 years following the end of pregnancy than women who did not initiate or continue antidepressants during pregnancy (odds ratioinitiation 2.16, 95% confidence interval 1.95 to 2.39; odds ratiocontinuation 2.40, 95% confidence interval 2.27 to 2.53). There was little evidence for any substantial association with autism (odds ratiomultivariableregression 1.10, 95% confidence interval 0.90 to 1.35; odds ratiopropensityscore 1.06, 95% confidence interval 0.84 to 1.32), attention deficit hyperactivity disorder (odds ratiomultivariableregression 1.02, 95% confidence interval 0.80 to 1.29; odds ratiopropensityscore 0.97, 95% confidence interval 0.75 to 1.25) or intellectual disability (odds ratiomultivariableregression 0.81, 95% confidence interval 0.55 to 1.19; odds ratiopropensityscore 0.89, 95% confidence interval 0.61 to 1.31) in children of women who continued antidepressants compared with those who discontinued antidepressants. There was inconsistent evidence of an association between initiation of antidepressants in pregnancy and diagnosis of autism in offspring (odds ratiomultivariableregression 1.23, 95% confidence interval 0.85 to 1.78; odds ratiopropensityscore 1.64, 95% confidence interval 1.01 to 2.66) but not attention deficit hyperactivity disorder or intellectual disability; however, but results were imprecise owing to smaller numbers.

Limitations

Several causal-inference analyses lacked precision owing to limited numbers. In addition, adherence to the prescribed treatment was not measured.

Conclusions

Women prescribed antidepressants during pregnancy had greater service use during and after pregnancy than those not prescribed antidepressants. The evidence against any substantial association with autism, attention deficit hyperactivity disorder or intellectual disability in the children of women who continued compared with those who discontinued antidepressants in pregnancy is reassuring. Potential association of initiation of antidepressants during pregnancy with offspring autism needs further investigation.

Future work

Further research on larger samples could increase the robustness and precision of these findings. These methods applied could be a template for future pharmaco-epidemiological investigation of other pregnancy-related prescribing safety concerns.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (15/80/19) and will be published in full in Health Technology Assessment; Vol. 27, No. 15. See the NIHR Journals Library website for further project information.

Decisions about the use of psychotropic medication during pregnancy: a qualitative study

OBJECTIVE

To understand the perspectives of women with severe mental illness concerning the use of psychotropic medicines while pregnant.

DESIGN

Interviews conducted by female peer researchers with personal experience of making or considering decisions about using psychotropic medicines in pregnancy, supported by professional researchers.

PARTICIPANTS

12 women who had had a baby in the past 5 years and had taken antipsychotics or mood-stabilisers for severe mental illness within the 12-month period immediately prior to that pregnancy. Recruitment to the study was via peer networks and the women interviewed came from different regions of England.

SETTING

Interviews were arranged in places where women felt comfortable and that accommodated their childcare needs including their home, local library and the research office.

RESULTS

The views expressed demonstrated complex attempts to engage with decision-making about the use of psychotropic medicines in pregnancy. In nearly all cases, the women expressed the view that healthcare professionals had access to limited information leaving women to rely on experiential and common sense evidence when making decisions about medicine taking during pregnancy.

CONCLUSIONS

The findings complement existing work using electronic health records by providing explanations for the discontinuation of psychotropic medicines in pregnancy. Further work is necessary to understand health professionals' perspectives on the provision of services and care to women with severe mental illness during pregnancy.

Update of strategies to translate evidence from cochrane musculoskeletal group systematic reviews for use by various audiences

For rheumatology research to have a real influence on health and well-being, evidence must be tailored to inform the decisions of various audiences. The Cochrane Musculoskeletal Group (CMSG), one of 53 groups of the not-for-profit international Cochrane Collaboration, prepares, maintains, and disseminates systematic reviews of treatments for musculoskeletal diseases. While systematic reviews provided by the CMSG fill a major gap in meeting the need for high-quality evidence syntheses, our work does not end at the completion of a review. The term "knowledge translation" (KT) refers to the activities involved in bringing research evidence to various audiences in a useful form so it can be used to support decision making and improve practices. Systematic reviews give careful consideration to research methods and analysis. Because the review is often long and detailed, the clinically relevant results may not be apparent or in the optimal form for use by patients and their healthcare practitioners. This paper describes 10 formats, many of them new, for ways that evidence from Cochrane Reviews can be translated with the intention of meeting the needs of various audiences, including patients and their families, practitioners, policy makers, the press, and members of the public (the "5 Ps"). Current and future knowledge tools include summary of findings tables, patient decision aids, plain language summaries, press releases, clinical scenarios in general medical journals, frequently asked questions (Cochrane Clinical Answers), podcasts, Twitter messages, Journal Club materials, and the use of storytelling and narratives to support continuing medical education. Future plans are outlined to explore ways of improving the influence and usefulness of systematic reviews by providing results in formats suitable to our varied audiences.

EFFECT OF EFFORT ON CHOICE: VALUE OF A SECONDARY REINFORCER

The present experiment tests the hypothesis that a secondary reinforcer associated with high effort would be preferred to the same secondary reinforcer with low effort. Preference was measured by (a) S's choice in a T-maze and (b) time spent in the presence of the secondary reinforcet. Each of 40 animals experienced both high and low effort conditions associated with either a vertical or a horizontal striped area. Half of the Ss experienced high effort with vertical and low effort with horizontal stripes. The other half experienced high effort with horizontal and low effort with vertical stripes. Results demonstrated that effort is effective in influencing the value of a secondary reinforcer.

RELATION OF CERTAIN PERSONALITY VARIABLES TO DECISION MAKING IN PERCEPTION

It was hypothesized that certain personality variables would be related to decision making in a guessing experiment. A stimulus set of 100 3- × 5-in. unlined filing cards, 75 of which contained circles and 25 of which were blank, was presented twice to each of 56 undergraduate Ss. The cards were in a random order and Ss were asked to guess whether a circle or a blank would be the forthcoming event. Their predictions on the second session's presentations were quantified in terms of the likelihood of false positive errors and hit rate over false alarm rate. Independently of the behavioral task, all Ss completed two personality inventories designed to assess need for approval and a dimension of internal vs external control of reinforcement. Scholastic Aptitude Test scores and Ss' estimates of the number of circles present in the stimulus set were incorporated as control variables. Results clearly show the effect of personality differences on guessing behavior. Subsequent related studies for psychophysics and judgmental responses were suggested.

PUNISHMENT BY NOISE IN AN ALTERNATIVE RESPONSE SITUATION

Operant responses of human subjects were conditioned according to a variable-interval schedule of positive reinforcement. A brief noise was delivered as punishment for each of the responses. The noise suppressed the punished responses more when an alternative unpunished response was concurrently available than when only a single punished response was available. This finding extends the generality of a previous study that had used a period of extinction rather than the brief noise as the punishing stimulus.