A growing body of research is demonstrating concordance between mother and child diurnal cortisol production. In the context of maternal history of depression, intergenerational concordance of cortisol production could contribute to hypercortisolemia in children of depressed mothers, which has been shown to increase risk for MDD. The current study is the first to examine concordance in diurnal cortisol production between mothers with a history of depression and their never-depressed, but high-risk, children. We collected salivary cortisol across 2 days from mothers with (remitted; RMD) and without (CTL) a history of recurrent episodes of depression and their never-depressed daughters. As expected, RMD mothers and their daughters both exhibited higher cortisol production than did their CTL counterparts. Moreover, both across and within groups, mothers’ and daughters’ cortisol production were directly coupled. These findings suggest that there is an intergenerational concordance in cortisol dysregulation that may contribute to hypercortisolemia in girls at familial risk for depression.
In the United States alone, 10–15 million children under the age of 18 live with a depressed parent (England & Sim, 2009); approximately half of these children will develop depression by adulthood (Beardslee et al., 1998, Goodman et al., 2011 and Williamson et al., 2004). Indeed, parental depression is associated with a three- to five-fold increase in children's risk for developing a depressive episode. Moreover, compared with children of well parents who develop depression, children of depressed parents tend to have an earlier age of depression onset, longer episode duration, and greater functional impairment (Hammen et al., 2003 and Keller et al., 1986). Little is known, however, about mechanisms through which risk for major depressive disorder (MDD) is transmitted from parent to child (Fig. 1).
Demographic and clinical characteristics of the CTL and RMD mothers and the CTL and RSK daughters are presented in Table 1. There were no significant group differences in mothers’ age, t(110) = 1.61, p = .110, ethnicity, χ2(N = 111) = 0.14, p = .713, education, χ2(N = 111) = 2.49, p = .115, body mass index (BMI), t(100) = 0.98, p = .328, or percent taking oral contraceptives, χ2(N = 111) = 1.41, p = .236. There were also no significant group differences in daughters’ age, t(110) = 0.07, p = .942, ethnicity, χ2(N = 112) = 0.20, p = .654, Tanner stage, t(105) = 0.51, p = .611, menarche status, χ2(N = 97) = 0.27, p = .606, or BMI, t(83) = 1.32, p = .191. The RMD mothers obtained significantly higher scores on the BAI than did the CTL mothers, t(110) = 5.97, p < .001; however, the RSK and CTL daughters did not differ in their scores on the ASIC, t(109) = 1.17, p = .245. The RMD mothers obtained significantly higher scores on the BDI than did the CTL mothers, t(110) = 6.94, p < .001, and the RSK daughters obtained slightly but significantly higher scores on the CDI than did the CTL daughters, t(110) = 3.50, p = .001. Importantly, sample collection times did not differ as a function of group for mothers or daughters at any time point, ts(1 1 0) < 1.98, ps > .05. Mothers’ first and second cortisol samples were taken an average of 30 min earlier than their daughters’ samples, ps < .001, the timing of mothers’ afternoon samples did not significantly differ from their daughters’ sampling times, and mothers’ evening samples were taken an average of 8 min after her daughters, p = .041.
