چرخش خاکستری ابر صورتی: تقلیل عاطفه مثبت نشانه های افسردگی پس از زایمان را پیش بینی می کند

Objective Maladaptive response styles to negative affect have been shown to be associated with prospective (postpartum) depression. Whether maladaptive styles to positive affect are also critically involved is understudied, even though anhedonia (a correlate of low positive affectivity) is a cardinal symptom of depression. The present study is the first to investigate the predictive value of cognitive response styles to both negative (depressive rumination) and positive affect (dampening) for postpartum depressive symptoms. Methods During the third trimester of pregnancy, 210 women completed self-report instruments assessing depression (symptom severity and current and/or past episodes) and scales gauging the presence of depressive rumination and dampening. Of these women, 187 were retained for postpartum follow-up, with depressive symptoms being reassessed at 12 (n = 171) and 24 (n = 176) weeks after delivery. Results Regression analyses showed that higher levels of dampening of positive affect during pregnancy predicted higher levels of depressive symptoms at 12 and 24 weeks postpartum, irrespective of initial symptom severity, past history of depression and levels of rumination to negative affect. Prepartum trait levels of rumination, however, did not predict postpartum symptomatology when controlled for baseline symptoms and history of major depressive episode(s). Conclusions The results of this investigation suggest that the way women cognitively respond to positive affect contributes perhaps even more to the development of postpartum depression than maladaptive response styles to negative affect.

Postpartum depression refers to a major depressive episode following childbirth [1] and affects as many as 7.1% of women in the first three months postpartum [2]. Given this high prevalence and the well-documented negative consequences of postpartum depression for both mother and child [1], many studies have been conducted to explore potential risk factors for this distressing condition. The greater part of this research typically looked into potential predisposing demographic factors and the pregnancy itself, whereas the role of cognitive risk factors was largely neglected [3] despite their being central to influential theories in the larger depression literature. For example, past research has shown that depressive rumination, a dysfunctional cognitive response style to negative or depressed affect, is critically linked to depression. Depressive rumination has been defined as a cognitive dwelling on one's sad or depressed feelings and the possible causes and consequences of these feelings [4]. “Why do I always feel like this?”, “Where did it all go wrong?” and “Will I ever feel better again?” are characteristic examples of ruminative thoughts. This typical response style to negative affect has been consistently shown to contribute to the development and maintenance of depressive symptoms and clinical episodes [5] and [6]. Thus, the more people respond to negative, sad or depressed feelings with such ruminative thinking, the more likely it is that these feelings will be prolonged, deepened and possibly progress to a (new) full-blown clinical depressive episode. Recent studies have provided preliminary evidence suggesting that depressive rumination may also play a role in the development of postpartum depression. For instance, in a group of pregnant women at risk of depression, rumination predicted prospective increases in depressive symptoms over a 3-month follow-up in those with poor social functioning [7]. It should be noted, however, that in only 41.6% (n = 26) of cases the follow-up was conducted after delivery. In another study, assessing depressive rumination during the third trimester of pregnancy in 101 women, found that it was not predictive of short-term depressive responses (baseline to 1-month postpartum), but that it did predict longer-term symptom changes (baseline to 2-months postpartum) [3]. In a final study prepartum rumination did not predict postpartum depressive symptoms five weeks after childbirth [8]. Considering all the above, depressive rumination during pregnancy is taken to be predictive of higher levels of postpartum depressive symptoms, which is in line with the general literature documenting a predictive association between rumination and depression. Arguably, postpartum symptoms may be limited to longer-term reactions (≥ 2 months postpartum) [3], while appearing less relevant in the immediate postpartum period [3] and [8]. Also, the handful of studies conducted so far are limited by their relatively small sample sizes (N < = 100) as well as by the fact that none of the studies took prior history of clinical depression into account. This latter omission is not without importance, since (a) prior history of clinical depression is a well-known risk factor for future depression, including postpartum depression [1] and [9], and (b) cognitive risk factors such as depressive rumination are often elevated in people with a history of depression [10]. Accordingly, before one can draw firm conclusions regarding the predictive value of any hypothesised risk factor, in this case a ruminative response style to negative or depressed affect, prior depression needs to be controlled for. Furthermore, recent research has made clear that focusing on how people respond to negative affect (e.g. by engaging in depressive rumination) may only tell us half the story of disrupted or maladaptive emotion regulation underlying depression. Depression is not only characterised by an increase in negative affect but also by a decrease in positive affect or a diminished ability to respond to positive affect, a construct related to anhedonia. Anhedonia is a central symptom of clinical depression, and refers to the inability to enjoy activities that the individual previously experienced as pleasurable and fun. Therefore, one could reasonably expect that depressed individuals and those vulnerable to depression also respond differently to positive affect, just as they differ from healthy individuals in how they cognitively deal with negative feelings. There is some preliminary evidence to suggest that this might indeed be the case, in that symptoms of depression appear to be associated with what is called a dampening cognitive response style to positive emotion. “I probably don't deserve this”, “Ah well, these good feelings won't last, you'll see”, “I shouldn't forget that there have been times that I wasn't so lucky”, are some examples of dampening thoughts people may resort to when feeling (particularly) happy [11]. Dampening basically comes down to effortful cognitive attempts to downregulate positive feelings which prevents an individual from fully enjoying or benefiting from pleasant experiences. Results of cross-sectional studies have shown that higher levels of dampening predict higher levels of concurrent depressive symptoms in students above and beyond depressive rumination [11], [12] and [13], as well as in children [14]. In another cross-sectional study students with clinically significant levels of depressive symptomatology self-reported significantly higher levels of dampening than the controls [15]. Also in students, lifetime history of depressive symptoms was found to be positively associated with higher dampening scores [16]. Finally, in a series of three cross-sectional studies, it was confirmed that the phenomenon was related to depressive symptoms in students, while they additionally showed that also clinically depressed adults reported higher levels of dampening than never-depressed controls [17]. Importantly, preliminary data furthermore indicate that the positive association between dampening and depression also holds prospectively. In two student samples our research group [18] found that increased levels of dampening responses predicted higher levels of depressive symptoms at follow-up while controlling for baseline depressive symptomatology and depressive rumination; but there is one nonreplication in children [14]. It was our conclusion that these preliminary results indicate that dampening responses to positive affect add useful information above and beyond ruminative responses to negative affect in explaining both concurrent and prospective symptoms of depression [18]. Still, the vast amount of studies documenting a robust positive association between (ruminative) responses to negative affect and depression stands in sharp contrast to the relatively few studies that have investigated and documented a link between (dampening) responses to positive affect and depression. It has been rightly noted [18] that such an asymmetry is to some extent understandable since depression is typically labelled as a disorder of elevated negative affect; yet anhedonia, a correlate of low positive affect, is of course the other cardinal symptom of depression. There is a clear need for more studies examining the involvement of maladaptive regulation of positive affect in explaining the development and persistence of depressive symptoms in other than student populations as the assessment of such response styles in at-risk and clinical populations may tell us the other half of the story of affect regulation deficits underlying depression in general and postpartum depression in particular. We do not know of any study that has looked at this side of the story, even though inadequate responses to positive emotions can be expected to play a (key) role especially in postpartum depression since pregnancy and giving birth are typically accompanied by a mixture of both negative and positive events and feelings. We want to stress that the current study aims to examine the predictive value of a certain response style (i.e. dampening) to positive affect for postpartum depressive symptomatology and not of low positive affect. The latter has been investigated in previous studies, showing that positive affect was predictive of fewer cases of postpartum depression [19] and [20] and less depressive symptomatology in the three months postpartum [19]. The present study hence aims to examine the predictive value of cognitive response styles to both negative and positive affect for prospective postpartum symptoms of depression. More specifically, using multiple regression analyses and by controlling for baseline depressive symptoms and prior history of major depression, we investigated whether depressive rumination and dampening predict postpartum depressive symptomatology.

The aim of the current study was to examine the predictive value of two cognitive regulatory styles of affect for postpartum depressive symptoms, depressive rumination and dampening. Documented extensively, depressive rumination is a maladaptive response style to negative/depressed affect known to elicit and aggravate (symptoms of) depression [5]. Dampening is maladaptive in that it renders people less or incapable of fully enjoying or benefiting from positive experiences, but its association with depression is far less well documented as depression research has only recently been directed to positive affect regulation. Still, there are preliminary findings suggesting that a dampening response style to positive affect goes hand in hand with depressive symptoms [13], [15], [17] and [18] and that it may even predict prospective levels of depression [18]. A first observation we made in our current prediction study was that depressive symptoms during pregnancy and a past history of major depressive episode(s) independently predicted postpartum depressive symptoms at 12 and at 24 weeks following childbirth, which result is in line with other robust findings in the postpartum depression literature showing that both factors are modest to strong predictors of postpartum depression [1]. Our second observation was that, once controlled for baseline prepartum depressive symptoms and prior history of major depressive episode(s), prepartum trait levels of depressive rumination did not predict postpartum symptomatology. This is in contrast with the vast amount of studies that did show depressive rumination to be involved in the development and maintenance of (non-postpartum) depression. However, the majority of these studies did not control for past history of major depression and our findings accordingly make clear that these earlier results need to be interpreted with caution. We also strongly suggest that future studies examining the role of depressive rumination in the development of (postpartum) depression assess lifetime history of depression as this variable may (largely) account for a possible positive association. The third and most salient finding of our study was that a dampening response to positive affect significantly predicted postpartum depressive symptoms both after 12 and after 24 weeks of delivery.4 Note that this was true when baseline prepartum symptoms, prior history of major depressive episodes – two well-established predictors – and depressive rumination were taken into account. To our knowledge, ours is the first study to demonstrate that dampening of positive affect prospectively predicts postpartum depressive symptoms and also the first to show that this holds true independently of a past history of major depression. The fact that a dysfunctional response style to negative affect depressive rumination was not predictive of postpartum depression symptoms furthermore strengthens the idea that the way people cognitively respond to positive feelings is at least as and in some cases even more important than the way they respond to negative feelings in explaining a vulnerability to depression. Up till now there is a marked and, as our results suggest, unjustified imbalance in depression research attention to negative versus positive emotion and the associated cognitive response styles. Finally, studies like the present one are sorely needed if we want to critically improve our understanding of mechanisms underlying positive emotion deficits such as anhedonia in major depression [17]. This is especially important given that anhedonia is typically associated with poorer outcome in depression [31], with existing therapies appearing inadequate in treating anhedonia satisfactorily [32]. In terms of clinical implications, our results demonstrate that in the prognosis (e.g. screening), prevention and treatment of (postpartum) depression, the regulation of positive emotion (maladaptive dampening in particular) needs to be considered alongside regulation of negative emotion. Results like ours suggest that “treatment approaches should be oriented to address elevated negativity and blunted positivity in a more even-handed fashion” [32, p. 327]. Based on our findings, reducing dampening might then be an important focus in treatment. One may, for instance, think of training at-risk or depressed individuals to become more aware of their dampening cognitions and offering them skills that will enable them to disengage from these habitual dysfunctional cognitive routines. Mindfulness-based techniques might be effective here [17]. Challenging positive metacognitive beliefs with respect to dampening may be another therapeutic avenue to explore in this respect. It is our clinical experience that depressed patients, including those suffering from postpartum depression, sometimes indicate that they deliberately or consciously downtone their positive feelings because they believe that by doing so they can protect themselves from negative outcomes (e.g. “It is best not to enjoy this moment too much, or I run the risk of feeling far worse when these positive feelings have faded. So I'd better temper my feelings of joy now”). Such seemingly positive beliefs about (the protective benefits of) modifying positive feelings may (partially) explain why this depressotypic thinking style is maintained in analogy to how positive beliefs about depressive rumination are thought to maintain ruminative thinking [33]. These erroneous metacognitive beliefs can then, for example, be challenged through metacognitive therapy [34]. However, future research will first need to empirically test to what extent metacognitive beliefs play a role in the development and maintenance of dampening responses to positive emotions, as has been done for beliefs about adverse responses to negative emotions. The main limitation of the present study is that we exclusively relied on self-report inventories for both our independent variables, the central emotion regulation styles, and postpartum depression, the dependent variable. Response biases (e.g. social desirability) and shared method variance may hence possibly have affected the reliability and validity of our results. Ideally, future studies along this line will also include other more objective measures such as an interview-based or clinician-rated assessment of depression symptoms and diagnosis. Also, we did not collect information on variables such as sleep or general health parameters that could function as moderators of some of the effects that we observed. It will also be important for future research to establish whether our findings generalise to more clinical samples and to other populations in terms of race and ethnicity. With respect to the latter, for example, research indicates that cultural differences exist in (the expression or moderation of) positive affect and, relatedly, the prevalence of anhedonia [35]. Notwithstanding these drawbacks, compared to previous cognitive emotion regulation research (especially in the area of postpartum depression), our study has clear strengths, most notably its relatively large sample size and the inclusion of prior history of depression, adding to the relevance of our findings.