Do glycaemic treatment targets affect the perinatal mental health status of women with gestational diabetes? - Data from the TARGET Trial.

BACKGROUND: Gestational diabetes mellitus is associated with perinatal mental disorders. Effective management may reduce this risk, but there is little evidence on effects of different glycaemic treatment targets. We assessed whether tight glycaemic treatment targets compared with less-tight targets reduce the risk of poor mental health outcomes in women with gestational diabetes. METHODS: This was a secondary analysis of data from women who consented to complete perinatal mental health questionnaires as participants in the TARGET Trial, a stepped-wedge cluster randomized trial in 10 hospitals in New Zealand. All hospitals initially used less tight glycaemic targets for management of gestational diabetes and were sequentially randomized, in clusters of two at 4-monthly intervals, to using tighter glycaemic targets. Data were collected from 414 participants on anxiety (6-item Spielberger State Anxiety scale), depression (Edinburgh Postnatal Depression Scale), and health-related quality of life (36-Item Short-Form General Health Survey) at the time of diagnosis (baseline), 36 weeks of gestation, and 6 months postpartum. The primary outcome was composite poor mental health (any of anxiety, vulnerability to depression, or poor mental health-related quality of life). Generalized linear mixed models were used to determine the main treatment effect with 95% confidence intervals using an intention-to-treat approach. RESULTS: We found no differences between randomised glycaemic target groups in the primary outcome at 36 weeks' (relative risk (RR): 1.07; 95% confidence interval 0.58, 1.95) and 6 months postpartum (RR: 1.03; 0.58, 1.81). There were similarly no differences in the components of the primary outcome at 36 weeks' [anxiety (RR: 0.85; 0.44, 1.62), vulnerability to depression (RR: 1.10; 0.43, 2.83), or poor mental health-related quality of life (RR: 1.05; 0.50, 2.20)] or at 6 months postpartum [anxiety (RR:1.21; 0.59, 2.48), vulnerability to depression (RR:1.41; 0.53, 3.79), poor mental health-related quality of life (RR: 1.11; 0.59, 2.08)]. CONCLUSION: We found no evidence that adoption of tighter glycaemic treatment targets in women with gestational diabetes alters their mental health status at 36 weeks' gestation and at 6 months postpartum. TRIAL REGISTRATION: The Australian New Zealand Clinical Trials Registry (ANZCTR). ACTRN12615000282583 (ANZCTR-Registration). Date of registration: 25 March 2015.