Gestational diabetes mellitus (GDM) is characterized by increased insulin resistance and carries perinatal and long-term risks for the mother and her offspring. There is a link between perinatal depression or anxiety and GDM. Mental health problems are associated with higher insulin resistance and could explain the underlying association between GDM and depression or anxiety symptoms. We investigated the trajectories and associations between symptoms of mental health and well-being with insulin resistance and metabolic health in women with GDM.
This study included the control group (n = 106) of a randomized controlled trial in women with GDM that were followed-up during pregnancy and up to 1-year postpartum. We measured symptoms of mental health (Edinburgh Postnatal Depression Scale (EPDS), Anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A), well-being (The World Health Organization Well-Being Index (WHO-5)) and metabolic health, including insulin resistance variables (HOMA-insulin resistance (IR) and Matsuda Index of insulin sensitivity) as well as weight during pregnancy and in the postpartum.
Participants' pre pregnancy weight and BMI were 69.7 kg ± 16.1 and 25.9 kg/m ² ± 5.5 respectively. HOMA-IR was higher during pregnancy compared to 6-8 weeks postpartum and increased between 6-8 weeks and 1-year postpartum (all p < 0.05). Matsuda index decreased between 6-8 weeks and 1-year postpartum (p < 0.001). EPDS scores decreased between pregnancy and both 6-8 weeks and 1-year postpartum (all p < 0.05). HADS-A scores did not change between pregnancy and the postpartum. WHO-5 scores improved significantly from pregnancy and both 6-8 weeks and 1-year postpartum (p < 0.001). Correlation coefficients within outcome at the three different time points were high for metabolic measures and ranged between 0.94 and 0.96 for weight, from 0.77 to 0.89 for HOMA-IR and 0.64 for the Matsuda index (all p < 0.001). Mental health and well-being variables were moderately correlated in all three time points including r = 0.36-0.55 for the EPDS (p < 0.001), r = 0.58 for HADS (p < 0.001), and r = 0.43-0.52 for the WHO-5 (p < 0.01). After adjustment for age and pre-pregnancy BMI, Matsuda index was negatively associated with EPDS scores and positively associated to WHO-5 scores at 6-8 weeks postpartum. No other association between insulin resistance and mental health or well-being outcomes were found.
While insulin resistance fluctuated with values being lowest in the early postpartum and increasing thereafter, both depression and well-being scores decreased between pregnancy and the postpartum and did not change in the postpartum period. Intraindividual variability was larger for mental health and well-being than for metabolic health outcomes at different time points, indicating a higher plasticity for mental health and well-being outcomes that could be acted upon. We found only few associations between mental health and well-being and metabolic health outcomes.