Stressful Work Trajectories and Depressive Symptoms in Middle-Aged Couples: Moderating Effect of Marital Warmth

Abstract

Objectives: The present study investigated the decade-long actor and partner infleunces between husbands’ and wives’ trajectories of stressful work conditions (SWCs) and their depressive symptoms while also considering the moderation of these influences by spousal warmth. Methods: Participants were 330 middle-aged dual-earner couples from the Iowa Midlife Transitions Project. Husbands and wives reported on own SWCs and reported on parenter’s warmth in the years of 1991, 1992, and 1994. Depressive symptoms for husbands and wives were measured by the SCL-90-R in 1994 and 2001. Structural equation models, growth curves, and longitudinal data were used to perform our analyses. Results: For husbands and wives, trajectories of SWCs over early middle years (1991-1994) contributed to depressive symptoms in 1994. Notably, for husbands and wives, the severity (level) of SWCs in 1991 had a persistent influence on depressive symptoms a decade later (2001). For husbands, under conditions of wives’ low warmth, SWCs exerted a relatively strong influence on their depressive symptoms. However, under conditions of high warmth from wives, most of these influences were greatly diminished. Discussion: Results from the current study indicate that contextual life experiences can have a persistent health influences over the life course.

Keywords

families life course social support employment depression

Husbands and wives experience increasing marital and parental responsibilities during their middle years, in addition to caring for aging parents and encountering numerous transitional life events (Lachman & James 1997). These family responsibilities combined with the increasing health risk and decline in some cognitive functions associated with advancing age (Bumpass & Acqulino, 1995; Lachman, 2003; Taylor & Lynch, 2004) may make them more susceptible to the detrimental health impact of stressful work conditions (SWCs; Wickrama, Kwag, Lorenz, Conger, & Surjadi, 2010). Moreover, the current middle-aged baby boom cohort emerges from a historical context in which they have experienced tough competition for high-quality work positions, organizational restructuring of the workplace, and corporate downsizing in the United States (Elder & O’ Rand, 1995; Moen & Wethington, 1999). In particular, rural areas, from which the study population is drawn, experienced the “farm crisis” of the 1980s, where chronically low prices displaced rural farmers from their lifelong careers as they searched for available work. Without acquiring new work skills, members of this cohort were susceptible to adverse changes in work conditions (Lorenz, Elder, Bao, Wickrama, & Conger, 2000).

In the current study, depressive symptoms are utilized as a proxy for poor mental health because research indicates that, in many ways, they are a cornerstone of psychopathology. For instance, individuals with depressive symptoms frequently report other internalizing symptoms, such as anxiety and somatization, and experience symptom continuity into later years (Keenan, Feng, Hipwell, & Klostermann, 2009; Merikangas & Avenevoli, 2002; Ollendick, Shortt, & Sander, 2005; Wu, Schimmele, & Chappell, 2012). Depressive symptoms are also relevant for studies, such as our own, examining interindividual associations between husbands’ and wives’ because depressive symptoms are associated with individuals’ ability to function successfully in both marital and parental roles (Marks, 1977; Rakow et al., 2011).

However, little research has investigated the influence of individual trajectories of SWCs on the mental health outcomes of middle-aged husbands and wives. To understand the lasting effects of SWCs in the context of individuals’ advancing age from early to late middle years, we draw on both the life course perspective (Alwin & Wray, 2005; Glymour, Ertel, & Berkman, 2009) and the life span perspective (Lerner, Dowling, & Anderson, 2002). Both perspectives move beyond age-specific development to recognize the continuity across interrelated life stages in explaining mental health outcomes (Fuller-Iglesias, Smith, & Antonucci, 2009). The life course perspective contends that contextual life experiences such as SWCs will have persistent health influences over the life course. The life span perspective complements this life course premise by incorporating associated individual-level processes. That is, we will explain the long-term mental health consequences of SWCs from early to late middle years using individual trajectories of SWCs, which can be considered as exogenous influence, and related intraindividual endogenous processes.

Furthermore, most previous studies have examined the influence of work characteristics on individual’s mental health (actor effects) and less attention has been devoted to dyadic associations over time, including crossover influences (partner effects) from one partner’s work characteristics to their partner’s mental health and contemporaneous associations between husbands and wives. Enduring relationships, such as long-term marriages, foster linked lives between partners, which can lead to dyadic (crossover) influences between husbands and wives. As shown in Figure 1, we will specifically investigate the decade-long mental health influences stemming from SWCs utilizing a dyadic analytical framework that incorporates assessments of both husbands’ and wives’ SWCs trajectories and the progression of mental health across middle adulthood.

Figure 1.

A model depicting longitudinal associations and transactional partner influences between stressful work trajectories and depressive symptoms.

While it is known that these hypothesized associations can be contextualized by the social context an individual experiences (Proulx, Buehler, & Helms, 2009), little is known about their enduring marital context, in particular, as a potential contextual moderator. Both life course and life span perspectives recognize the importance of social relations with advancing age in relation to health outcomes. Linked lives, such as through marriage, enhances social relationships (e.g., spousal support), which may accumulate through lifelong experiences (Elder, 1998). Consistent with the life span perspective, aspects of an individual’s social relationships, such as spousal support, can also be conceptualized as an individual characteristic that shape individual processes. Positive family and marital relationships help individuals feel competent in their ability to cope with stressful situations and buffer the adverse influence of stress on health outcomes. We will examine how hypothesized associations involving SWCs and depressive symptoms vary depending on each spouse’s warmth toward their partner (contextual moderation).

SWCs and Depressive Symptoms

SWCs have been associated with numerous health problems including negative physical and mental health risks with advancing age (Bonde, 2008; Mezuk, Bohnert, Ratliff, & Zivin, 2011; Ollendick et al., 2005; Stansfield & Candy, 2006). As previously noted, SWCs may be particularly salient for long-married, middle-aged working parents with marital and parental role commitments. In addition, research suggests that midlife is a sensitive developmental period during which mental and physical health problems proliferate and accumulate resulting in increased health heterogeneity (Lachman & James, 1997; Wickrama et al., 2010). Within the theoretical alliance of life course and life span, we will draw from several micro-level theories and previous empirical evidence to elaborate individual-level processes involving SWCs and depressive symptoms.

Stress appraisal theory (Lazarus, 1999) contends that when an individual is exposed to a stressor, he or she subjectively appraises its threat and stressfulness and assess available resources to manage the stressor. This intraindividual process often leads to negative feelings, such as fear and worry. The stress process theory (Pearlin, Schieman, Fazio, & Meersman, 2005) posits that stressful work experiences contribute to depressive symptoms directly and indirectly (Figure 1). Exposure to chronic stressful conditions may repeatedly and consistently evoke negative emotions, which in turn contribute to elevated levels of depressive symptoms. Furthermore, the negative effects of SWCs in part stem from the fear, uncertainty, powerlessness, and helplessness that result from constant worry (De Witte, 2005; Nella, Panagopoulou, Galanis, Montgomery, & Benos, 2015). Excessive worry due to chronic or increasingly stressful work can lead to above average levels of negative emotions (Culpepper, 2009).

Examples of a particularly stressful working condition include having demanding, but unstable, work without being offered adequate rewards or promotion prospects (Siegrist, 1996). Thus, drawing from work-stress research, we developed a composite measure capturing several dimensions of SWCs, including work demand (e.g., work load; Story & Repetti, 2006), lack of reward and opportunities (Siegrist, 1996), ambiguity or uncertainty about future (e.g., work insecurity; Breaugh & Colihan, 1994), and work-relationship problems (e.g., arguments with a supervisor; Gilbreath & Karimi, 2012).

An examination of individual trajectories of SWCs over time will allow us to elucidate individual-level processes; in that, depressive symptoms of an individual are dynamically related to intraindividual changes in SWCs. In other words, not only the level of SWCs (i.e., severity) but also changes in SWCs over the middle years are expected to uniquely contribute to subsequent mental health outcomes (Wickrama, Lorenz, O’Neal, & Lee, 2016). For example, the mental health process of an individual already exposed to SWCs who experiences a sharp increase in SWCs from “moderate” to “very high” is qualitatively different from the mental health process of an individual who experiences the same amount of increase in SWCs from “zero” to “moderate” over the same period of time. Although these individual trajectories of SWC have the same amount of change they have important differences, specifically the ultimate level of SWCs experienced (very high compared with moderate). These two courses of development may have unique mental health consequences. That is, depressive symptoms may not correspond simply to chronically high levels of SWCs (i.e., severity), which can be approximated by the initial trajectory levels; instead, depressive symptoms may also be related to change (i.e., nature and the amount of growth/decline) in SWCs (Wickrama et al., 2016). Although it is important to understand this intraindividual process involving relative contributions of different growth parameters of SWCs to subsequent mental health risk (Rueter, Scaramella, Wallace, & Conger, 1999; Wickrama, Conger, Wallace, & Elder, 2003), traditional analytical methods are not sensitive enough to distinguish between unique contributions of different growth dimensions (i.e., level and rate of change) of SWCs to subsequent mental health risk.

Possible Indirect Influences of SWCs on Mental Health

Although not shown in Figure 1 and not tested explicitly in the current study, previous studies suggest that indirect influences account for the impact of stressful work experiences on depressive symptoms. These indirect influences are largely attributed to the erosion of personal resources, such as self-regulation, self-esteem, or mastery. For instance, some have shown that the erosion of resources can contribute to the failures in other life domains such as marriage (spillover hypothesis; Greenhaus & Beutell, 1985; Marks, 1977; Stevens, Kiger, & Riley, 2006), which may have subsequent mental health consequences. In the present study, we will examine the total association (both direct and indirect) between trajectories of SWCs and depressive symptoms over the middle years of life. Studies have suggested that depleted psychological resources, such as self-esteem, influenced by SWCs, directly foster depressive symptoms (Whisman & Kwon, 1993; Wickrama, Mancini, Kwag, & Kwon, 2012) through rumination (Orth, Robins, & Roberts, 2008). Rumination on negative aspects of self is closely associated with depression (Nolen-Hoeksema, 2000).

Crossover Influences: Partner Effects

As previously noted, linked lives are generally thought to foster crossover influences between husbands and wives in enduring marriages. Crossover occurs when one person’s experiences affect their partner’s well-being (Westman, 2001). As such, one spouse’s SWCs may operate as a stressor for their partner and, consequently, generate depressive feelings for the partner through emotional contagion (partner effect; Westman, 2001). Research suggests that, SWCs inflict negative moods through spillover and crossover processes (Devine, Connors, Sobal, & Bisogni, 2003; Van Emmerik & Jawahar, 2006; Westman, 2001) as SWCs may spillover to family and increase negative moods at home (Van Emmerik, & Jawahar, 2006) and also increase negative moods for the spouse (one spouse’s negative feelings may play a role in their partner’s subsequent development of negative feelings (partner effect; Westman, 2001).

Furthermore, although some daily dairy studies have established the transmission of emotions between spouses (Larson & Almeida, 1999), less work has identified the crossover, or emotion transmission, between partners stemming from an external stressor and continuing over a decade. These long-term crossover influences from SWCs to mental health influences on middle-aged husbands and wives may stem from different enduring mechanisms compared with short-term influences, which are generally the focus of daily dairy studies. Thus, as shown in Figure 1, in a dyadic framework, we assess both long-term actor and partner effects involving SWCs, elevated depressive symptoms, and the progression of depressive symptoms over time.

Progression of Depressive Symptoms Over Middle Years

Research suggests that individuals who suffer from depressive symptoms are at risk of subsequent depressive symptoms at later life stages. Early high levels of depressive symptoms are the best known predictor of later depression (Keenan et al., 2009). As previously noted, midlife is a sensitive developmental period which is dense in life events (or nonevents) and circumstances related to multiple roles involving work (e.g., promotions or lack thereof), aging parents (parental care), children (educations and occupational attainment/failures) and marriage (marital disruptions, divorce). Furthermore, the incidence of chronic disease and physical impairment increases with advancing age (Lorenz, Elder, Bao, Wickrama & Conger, 2000; Martikainen, Stansfeld, Hemingway, & Marmot, 1999; Ryff, Singer, & Palmersheim, 2004; Siegler, 1997), which may accelerate and compound mental health risk contributing to adverse intraindividual psychological process resulting in the continuity of depressive symptoms with advancing age.

Moderation of Spousal Warmth

Husbands and wives of enduring marriages may have varying sensitivity to social relationship (e.g., spousal support), but these relationships may also be shaped by personal characteristics and lifelong experiences (Elder, 1998). A central aspect to social relationships, particularly with advancing age, is spousal warmth or support (Glass, de Leon, Bassuk, & Berkman, 2006). Regarding spousal warmth toward one’s partner, Lorenz, Conger, Montague, and Wickrama (1993) found that the expression of warmth (expressing love, care, and affection) by one spouse protected their partner from the detrimental mental health impact of family economic stress. More recently, spouses’ emotional support behaviors were shown to moderate the association between spouses’ hostile behavior and their partners’ depressive symptoms (Proulx et al., 2009). In a similar vein, we expect that loving, caring, and affectionate behavior by one’s spouse may directly counteract the mental health risk stemming from the individual’s SWCs. This is consistent with psychophysiological research showing that psychosocial resources preemptively decrease stress reactivity by reducing the initial emotional stress response (Eisenberger, Taylor, Gable, Hilmert, & Lieberman, 2007).

Furthermore, consistent with interdependence theory (Kelley & Thibaut, 1978) and emotional investment perspective (Berscheid, 1983), couples who are emotionally invested in one another, as reflected by spousal warmth, show higher levels effective marital functioning (Berscheid, Snyder, & Omoto, 1989; Knobloch & Solomon, 2004). We contend that these closely associated marital attributes, including spousal warmth, support, and effective marital functioning, may operate as psychosocial resources for husbands and wives as they seek to effectively cope with stressful work experiences. That is, we expect that spousal warmth may buffer husbands and wives from the negative mental health effects of SWCs (Lorenz et al., 1993).

The Model

As depicted in Figure 1, our model begins with estimating individual trajectories of SWCs during respondents’ early middle years (average age of husbands and wives was 40 and 42, respectively) as characterized by the level of SWCs and change in SWCs over time (from 1991 to 1994). Our essential thesis is that their trajectories of perceived SWCs (both initial level and rate of change) will contribute to poor mental health that progresses over their middle years (from 1994 to 2001). This examination of trajectories allows for an estimation of the sample’s average initial level of SWCs (in 1991) and the average slope (i.e., rate of change) in SWCs over time (from 1991 to 1994). In addition, such an examination estimates the interindividual variability around these sample averages. For example, at the first measurement occasion in 1991, we expect that individuals differ in their level of SWCs. Furthermore, the stressfulness of work may decrease over time for some and increase over time for others. These variations in the rate of change create interindividual variability in the slope of SWCs over time. This variation in the rate of change can be modeled as a determinant of subsequent mental health outcomes (Wickrama, Beiser, & Kaspar, 2002).

We hypothesize the following:

Hypothesis 1: For husbands and wives in their early middle years (i.e., early 40s), the initial level and rate of change in SWCs (1991-1994) will influence their own depressive symptoms in 1994.

Hypothesis 2: For husbands and wives in their early middle years (i.e., early 40s), the initial level and rate of change in SWCs (1991-1994) will influence their own depressive symptoms in later middle adulthood (2001) directly and indirectly through depressive symptoms in 1994 (i.e., progression or continuity).

Hypothesis 3: The growth factors (i.e., the level and change) of SWCs for husbands and wives will be correlated contemporaneously as will their depressive symptoms in both 1994 and 2001.

Hypothesis 4: Longitudinal crossover will be present between husbands’ and wives’ SWCs and depressive symptoms in early (1991) and later (2001) middle adulthood; such that, each spouse’s SWCs will influence their partner’s subsequent depressive symptoms. Similarly, each spouse’s depressive symptoms in 1994 will influence their partner’s depressive symptoms in 2001.

Hypothesis 5: Spousal warmth toward the partner will moderate the association between each spouse’s SWCs and his or her own depressive symptoms outcomes.

We discuss these hypothesized associations in the paragraphs that follow.

Method

Participants and Procedures

The data utilized are from a subsample of 330 dual-earner husbands and wives who participated in the larger Iowa Midlife Transitions Project (MTP). These men and women were originally part of the Iowa Youth and Families Project (IYFP) in 1989, 1990, 1991, 1992, and 1994, and then continued on to participate in the MTP in 2001. For both projects, trained field interviewers visited the families in their homes. During the visit, a trained interviewer asked each family member to complete a detailed questionnaire about family life, work, finances, friends, and mental and physical health status. Family members completed the questionnaires independently so that they could not see one another’s answers. The full IYFP (1989-1994) sample included 451 families from eight counties in Iowa (see Conger & Elder, 1994), at the start of the MTP (2001), 370 families continued to participate in the project. The attrition rate for the combined sample was 11% across the 12-year period (1989-2001). Out of the 370 complete cases in 2001, 330 couples comprised consistently employed husbands and wives. Thus, we tested our model with a sample of 330 dual-earner couples who provided complete data on the items assessed in the current study in 2001.

The site for the research was determined by interest in rural economic stress (i.e., the farm crisis) and well-being. Because many of the outcomes and processes considered in the overall study were concerned with children’s development, families selected to participate had to have at least two children. Eligible families were identified through contacts with the public and private schools within the eight counties. Of the eligible families, 78% agreed to participate. At the first wave of IYFP data collection in 1989, about 96% of the husbands and 78% of the wives were employed. Median yearly family income in 1989 was US$33,240 (ranged from US$0 to US$259,000). In terms of occupational status, the men in this sample included craftsmen, foremen, and farmers (38.4%); professionals, managers, owners, and officials (23.8%); operatives and kindred workers (16.6%); sales workers, clerical, service workers, private household workers, and military service (14.4%); laborers (3.3%); and other (3.5%). Nineteen percent of the wives were homemakers. Occupations for the employed women included sales workers, clerical, service workers, and private household workers (46.1%); professionals, managers, owners, and officials (23.7%); operatives and kindred workers (4.2%); craftsmen, foremen, and farmers (2.9%); laborers (0.7%); and other (3.4%). In 1989, husbands and wives were generally in their early middle years; the average ages of husbands and wives were 40 and 38 years, respectively, with a range from 32 to 57 for husbands and 29 to 53 for wives). On average, the couples had been married for 17 years and had three children from their marriage together. The median age of the youngest child was 10. In 1989, the average number of years of education for husbands and wives was 13.68 and 13.54, respectively. Because there were very few minorities in the rural area studied, all families in the sample were White. This study used full information maximum likelihood (FIML), available in AMOSs software, to test the hypotheses using all available data. We further tested the model with and without the inclusion of the missing cases and found no significant differences in the results.

Measures

SWCs

Eight items captured perceived SWCs across multiple dimensions, including work insecurity, work stress, inadequacy of reward/income, lack of opportunities for advancement, and conflict with the supervisor. These specific dimensions were selected for inclusion based on previous research establishing their detrimental additive impact on various well-being indicators. Husbands and wives completed these items in 1991, 1992, and 1994. These items include, “I have a lot of conflict with my supervisor,” “I am always concerned I might lose this job,” “This job provides good job security,” “People at work ignore my feelings about things,” “There is a lot of stress and tension in this job,” “I have too many hours to work,” and “My job provides a good income.” The items were rated using a 7-point Likert-type scale (1 = never, 7 = always) and reverse scored, when necessary, so that higher scores indicated more SWCs. Mean scores were computed separately for husbands and wives at each of the three time points. The internal consistencies for perceived SWCs were .72 and .70 for husbands and wives in 1991, .71 and .70 in 1992, and .70 and .69 in 1994. Reports in 1991, 1992, and 1994 were used as repeated measures to estimate trajectories of SWCs for husbands and wives.

Depressive symptoms

In 1994 and again in 2001 using the SCL-90-R depression scale (Derogatis, 1983), participants were asked to assess their level of distress (1 = not at all to 5 = extremely) during the previous week. Computing an average across the 13 specific symptoms (e.g., feeling down, loss of sexual interest or pleasure, crying easily, and feeling no interest in things) yielded an index of depressive symptoms with higher scores indicating more depressive symptoms. The internal consistencies for scores of depressive symptoms were .90 and .91 for husbands and wives, respectively, in 1994 and .88 and .89 for husbands and wives in 2001.

Spousal warmth

In 1991, 1992, and 1994, 10 items were used to capture spousal reports of expressions of warmth from their partners during interactions in the month preceding survey completion. Sample items include how often in the past year their spouse: “Let you know she/he really cares about you,” “Acted loving and affectionate toward you,” and “Told you she/he loves you.” The items were rated using a 7-point Likert-type scale (1 = always, 7 = never) and reverse scored with higher scores indicating greater warmth. Mean scores were then computed for husbands and wives separately for each data collection time point. Using these scores, a mean was then computed across the three time points for husbands and wives separately creating two mean scores (i.e., cumulative warmth expressed by husbands and wives). These overall means of spouses’ reports of their partner’s warm behaviors were used as the moderating variables in the analyses. The internal consistencies for the six initial warm interaction scales (i.e., husbands’ and wives’ reports from 1991, 1992, and 1994) ranged from .85 to .88.

Analyses

A series of models were tested within a structural equation modeling (SEM) framework (AMOS 23, Arbuckle, 2014). First, to investigate the severity and change in SWCs over the early middle years, we tested univariate growth curves for SWCs of husbands and wives. Second, to test Hypotheses 1 to 4, we analyzed associated growth curves for husbands and wives predicting subsequent depressive symptoms including contemporaneous and longitudinal associations between husbands and wives as well as transactional associations between spouses. Third, we tested Hypothesis 5, the contextual moderation by the perceived level of spousal warmth, by conducting separate (i.e., “stacked”) analyses to determine how associations within the model differ under conditions of low and high spousal warmth (median split).

We used a range of indices to evaluate model fit including the chi-square statistic. When the chi-square divided by the degrees of freedom is below 3.0, the model is thought to fit the data well (Carmines & McIver, 1981). In addition, we used the Comparative Fit Index (CFI) and the root mean square error of approximation (RMSEA) to evaluate the SEMs because these two indices are not directly related to the sample size. When the CFI value is close to or greater than .95 and the RMSEA value is close to or less than .06 this is evidence that the model fits the data well (Hu & Bentler, 1999).

Results

Correlations Among Study Variables

As presented in Table 1, correlations among the study variables indicated that husbands’ depressive symptoms in 1994 and 2001 were significantly correlated with husbands’ SWCs at all three time points (r ranged from .26 to .38, p < .01) suggesting that experiencing more SWCs was associated with experiencing more depressive symptoms. In addition, wives’ depressive symptoms in 1994 and 2001 were significantly correlated with wives’ SWCs at all three time points (r = .16-.24, p < .01). Husbands’ depressive symptoms in 1994 and 2001 were significantly correlated (r = .54, p < .001) as were wives’ depressive symptoms in 1994 and 2001 (r = .51, p < .001). Wives’ reports of husbands’ warmth were significantly correlated with wives’ SWCs at all three time points and depressive symptoms at both time points (r = .11-.24, p < .05), suggesting that wives who had husbands who expressed more warmth experienced fewer depressive symptoms and SWCs. Husbands’ reports of wives’ warmth were not significantly correlated with husbands’ SWCs, but were significantly correlated with husbands’ depressive symptoms in 1994 (r = .17, p < .05).

Table 1.

Univariate and Bivariate Statistics for Study Variables.

	SWCs 1991	SWCs 1992	SWCs 1994	Dep. Sym. 1994	Dep. Sym. 2001	Warmth 91-94
1. SWCs 1991	.10	.62***	.13*	.24***	.20***	−.18**
2. SWCs 1992	.70***	.13*	.13***	.24***	.19***	−.11*
3. SWCs 1994	.56***	.67***	.06	.16***	.09	−.11*
4. Dep. Sym. 1994	.26***	.34***	.38**	.09	.51***	−.24**
5. Dep. Sym. 2001	.26***	.32***	.27**	.54**	.16**	−.21**
6. Warmth 91-94	−.02	−.04	−.02	−.17**	−.11	.45**
M—Husband (wife)	2.60 (2.50)	2.67 (2.57)	2.58 (2.62)	1.35 (1.59)	1.43 (1.53)	9.78 (.9.74)
SD—Husband (wife)	0.50 (0.48)	0.53 (0.48)	0.52 (0.54)	0.43 (0.59)	0.47 (0.52)	0.93 (1.05)

Note. Husband correlations are below the diagonal. Wife correlations are above the diagonal. Within-spouse correlations are shown on the diagonal. SWCs = stressful work condition; Dep. Sym. = depressive symptoms.

p < .05. **p < .01. ***p < .001.

Univariate Growth Curves of SWCs

Before estimating our hypothesized model, univariate linear growth curves of SWCs were estimated for husbands and wives separately using repeated measures in 1991, 1992, and 1994. Overall, respondents were relatively neutral on items assessing their level of SWCs with a mean of approximately 2.50 on a 5-point scale. Both linear growth curves of SWCs showed an adequate fit with the data (CFI was greater than .92). Across the sample, there was no average increase or decrease in SWCs for wives and husbands over time (mean slope of .01 and –.01, respectively). However, there was statistically significant variation for husbands and wives in both the initial level (.16 and .25, respectively, for wives and husbands, p < .05) and the rate of change or slope (.13 and .03, respectively, for wives and husbands, p < .05) of SWCs. These results suggested that experiences of SWCs varied across the sample. Furthermore, SWCs may have decreased for some and increased for others, creating interindividual variability in the change in SWCs over time for both husbands and wives. In these growth curves, the initial level and rate of change in SWCs were not significantly associated with each other for either husbands or wives.

Testing the Hypothesized Model

The results from our hypothesized model are presented in Figure 2. The initial level and rate of change in SWCs were generally of consequence for husbands’ and wives’ experience of depressive symptoms in 1994 (for the level and slope, b = .43 and .93 for husbands, and .44 and .15 for wives, p < .05). Growth factors for husbands’ SWCs were not associated with wives’ corresponding growth factors. For both husbands and wives, their initial level of SWCs predicted their depressive symptoms 10 years later in 2001 after controlling for depressive symptoms in 1994 (b = .16 and .10, respectively, p < .05). These findings represent the cumulative effect of early SWCs on depressive symptoms over the middle years. There was moderate continuity in reported depressive symptoms from 1994 to 2001 (b = .47 and .44 for husbands and wives, respectively), and husbands’ depressive symptoms were cross-sectionally associated with those of wives both in both 1994 and 2001 (.04 and .02, respectively, p < .05), suggesting contemporaneous dependency between husbands and wives, or a crossover influence between husbands and wives. However, there was a lack of evidence for longitudinal crossover associations between spouses (i.e., partner effects) involving growth factors of SWCs or depressive symptoms. The only statistically significant longitudinal crossover influence found was from wives’ depressive symptoms in 1994 to husbands’ depressive symptoms in 2001. The model explained 32% and 27% of the variance in husbands’ and wives’ depressive symptoms in 2001. The model fit indices suggested that this model fit the data well, χ²(df) = 63.17 (26) p = .05, CFI = .95, RMSEA = .06.

Figure 2.

Trajectories of SWCs in early middle years and the progression of depressive symptoms in middle-aged husbands and wives.

Testing Moderating Effects

Next, the moderating effects of husbands’ and wives’ reports of spousal warmth were assessed. Because, for both husbands and wives, the influence of the initial level of work stress (in 1991) showed consistent, intraindividual influences on depressives symptoms in 1994 and 2001 and given the somewhat limited sample size, we tested simplified models including husbands’ and wives’ SWCs in 1991 and depressive symptoms in 1994 and 2001 for low and high spousal warmth groups (median split; see Figure 3). The moderation hypothesis was supported for husbands. That is, under conditions of low warmth (average of 1991, 1992, and 1994 husbands’ reports of wives’ expressed warmth), husbands’ SWCs in 1991 exerted a relatively strong effect on their depressive symptoms in 1994 and 2001 (b = .33 and .17, respectively, p < .05). However, under conditions of high spousal warmth, the observed influences of SWCs on depressive symptoms in 1994 and 2001 were notably smaller (b = .13 and .06, p > .10; see Panel A of Figure 3). A multigroup comparison using equality constraints indicated the difference in these regression coefficients was statistically significant. In addition, although wives’ depressive symptoms in 1994 were related to husbands’ depressive symptoms in 2001 (b = .20, p < .05) under conditions of low warmth, under conditions of high warmth this association was not present (b = .02, p > .10). As shown in Panel B of Figure 3, moderating influences were not found for warmth expressed by husbands on the association between wives’ SWCs in 1991 and their depressive symptoms in 1994 and 2001. The continuity in depressive symptoms from 1994 to 2001 for both husbands and wives was not moderated by spousal warmth.

Figure 3.

Moderation effect of spousal warmth on the mental health influence of SWCs.

Discussion

Roles as spouses, children of aging parents, and parents to adolescents may lead to increasing family role responsibilities for middle-aged husbands and wives, which can make them more susceptible to the detrimental health impact of SWCs (Lachman & James, 1997; Wickrama et al., 2010). Most previous studies have examined intraindividual health effects (actor effects) of individual factors, such as psychological characteristics and personality traits, and less attention has been devoted to long-term influences of extrafamilial factors on mental health in middle adulthood. In the present study, we examined the decade-long actor and partner influences between husbands’ and wives’ trajectories of SWCs and their depressive symptoms across their middle years using a dyadic analytical framework. We also examined how these depressive symptoms progress with advancing age and the contextual moderation of these influences under varying levels of spousal warmth. To understand this complex web of influences with advancing age, we drew from both the life course (Alwin & Wray, 2005; Glymour et al., 2009) and the life span perspectives (Lerner et al., 2002). Both of these perspectives recognize the role of continuity across interrelated life stages in explaining mental health outcomes (Fuller-Iglesias et al., 2009).

Consistent with these perspectives, results from the current study indicate that contextual life experiences can have a persistent health influences over the life course. More specifically, this intraindividual process was identified for trajectories of SWCs. Thus, the life course notion of “contextual life experiences” was complemented by the life span focus on individual-level processes when explaining mental health outcomes for this sample of middle adults with advancing age. The results provided a deeper understanding about the intraindividual process that connects SWCs to husbands’ and wives’ depressive symptoms. Both the level and rate of change in SWCs in the early middle years (1991-1994) contributed to depressive symptoms in 1994. Furthermore, depressive symptoms generally continued over the middle years with moderate stabilities (coefficients greater than .40) from 1994 to 2001. This continuity operated largely through intraindividual continuities, although there was some evidence of crossover influences, primarily for contemporaneous (i.e., cross-sectional) associations between husbands and wives during the middle years.

For both husbands and wives, the level and change in SWCs in the early middle years (1991-1994) showed proximal influences on depressive symptoms in 1994. Thus, the development of depressive symptoms may not correspond simply to experiencing a large number of SWCs (i.e., severity), which can be approximated by the initial trajectory level. Rather, depressive symptoms corresponded to the individual’s rate of change (incline or decline) in SWCs for both wives and husbands. These findings suggest that both the severity and the deterioration, or recovery, of SWCs uniquely contribute to depressive symptoms over time. We believe that these associations may largely be attributed to intraindividual spillover of work stress to the family roles of middle-aged husbands and wives; however, these specific mechanisms were not tested in the current study. Future studies should elucidate these mediating spillover processes linking SWCs and poor mental health. More importantly, the initial levels of trajectories of SWCs exerted a long-term influence on depressive symptoms in 2001 after controlling for individuals’ previous levels of depressive symptoms in 1994. These long-term influences are evidence for the accumulating mental health impact of stressful experiences over the middle years (Willson, Shuey, & Elder, 2007).

Interestingly, regardless of the enduring marriages experienced by the current sample respondents, which is evidence for their “linked lives,” the results did not provide evidence of longitudinal crossover influences involving husbands’ and wives’ SWCs and their depressive symptoms in 1994 and in 2001. This suggests that the direct longitudinal influences of SWCs in these middle-aged husbands and wives are largely intraindividual. It appears that husbands’ SWCs are not a direct stressor for wives and vice versa. However, the statistically significant associations between husbands’ and wives’ depressive symptoms in 1994 indicate contemporaneous crossover influences. Future studies should further elucidate these dependencies.

The results also demonstrated the progression of depressive symptoms for both husbands and wives over the middle years with advancing age. Experiencing depressive symptoms in the early middle years was a risk factor for subsequent depressive symptoms for both husbands and wives (Keenan et al., 2009). Moreover, the results showed a crossover influence from wives to husbands over time. For example, wives who experienced higher levels of depressive symptoms in 1994 generally had husbands who reported more depressive symptoms in 2001, not vice versa. The progression of depressive symptoms in husbands and wives, in turn, may have an adverse influence on their marital and parental role performances resulting in poor outcomes for multiple family members (Conger, Conger, & Martin, 2010). Furthermore, it may also be that husbands and wives self-select marriage partners with similar levels of depressive symptoms. Thus, individuals with more depressive symptoms may select partners with similarly high levels of depressive symptoms.

More importantly, the present study tested the moderating effect of spousal warmth on the associations between SWCs and depressive symptoms for husbands and wives. We posited that caring, loving, and affectionate behaviors by one spouse toward their partner (i.e., expressions of warmth) may buffer partners from the adverse mental health consequences of SWCs. Within the tested moderation models, results suggest that, for husbands, wives’ warmth plays an important buffering role in the effects of SWCs (assessed in 1991) on subsequent depressive symptoms (assessed in both 1994 and 2001). For husbands with a spouse who exhibited high levels of warmth, most of the mental health effects of SWCs were greatly diminished compared with the mental health effects for those receiving low levels of warmth. These results suggest that loving, caring, and affectionate behaviors of wives can protect husbands form adverse health effects that often stem from a stressful environment (Lachman & Weaver, 1998). It seems that psychosocial resources preemptively moderate stress reactivity by reducing the initial emotional stress response for husbands (Eisenberger et al., 2007). It is important to note that the association between wives’ SWCs and their own depressive symptoms was not moderated by husbands’ expression of spousal warmth (as reported by wives). Husbands’ warmth may not be an effective resource for coping with SWCs for wives. Perhaps, husbands’ provision of other forms of support (e.g., instrumental and financial support) is more beneficial than expressions of warmth for reducing the detrimental impact of SWCs, particularly for dual-earner couples. This is in line with research on the division of labor within marital relationships, which has emphasized the various types of labor performed by couples and their differential effects, including emotion work (including social support and providing warmth), child care tasks, and household management work (both inside and outside; e.g., laundry and maintaining the yard, respectively; Erickson, 1993; Newkirk, Perry-Jenkings, & Sayer, 2017). Consequently, future research should further investigate both this gendered moderating influence of spousal warmth and consider potential moderating influences of other types of household labor.

There are several limitations to the current study that should be noted. The first limitation is related to the generalizability of the results. The sample comprised only European American dual-earner couples that lived in areas of rural Iowa during the farm crisis of the 1980s. Future studies testing similar models with a more diverse population are needed. For instance, future samples should include multiple ethnicities, greater variation in length of marriage, and other geographic locations. Because of our focus on the moderation by spousal warmth in dual-earner families, nonmarried adults in the larger study were not included in the sample. Thus, from the current findings, it is unclear whether the detrimental mental health impact of SWCs varies across parent, married single-earner, and married dual-earner families. In addition, except for spousal warmth, which was reported by the spouses, other measures were self-reported, which may be associated with self-report biases. Also, the time interval between available repeated measures of depressive symptoms was 7 years. This relatively long measurement interval did not allow for an exploration of the intricacies of change in depressive symptoms during the middle years. Finally, although psychophysiological research suggests that chronic work stress exerts psychological, physiological, and behavioral consequences, the present study focused exclusively on psychological consequences.

Despite these limitations, the present study contributes to the enhancement of knowledge about long-term influences of dual-earner couples’ SWCs and associated dyadic influences between husbands and wives. The results suggest that both the severity and change in SWCs in the early middle years can have powerful implications for husbands’ and wives’ depressive symptoms over their middle years. These findings have strong implications for workplace environments given the relatively chronic nature of depressive symptoms and the trend for aging individuals to continue to work longer than in the past (Mermin, Johnson, & Murphy, 2007). Furthermore, the experience of depressive symptoms influences an individual’s ability to work (Lerner et al., 2010), and recent reports suggest that depression has an estimated cost of between US$36.6 and US$51.5 billion annually in the United States due to lower work performance and absences (Kessler et al., 2006; Stewart, Ricci, Chee, Hahn, & Morganstein, 2003).

Thus, improvements to treatment, increased availability of treatment, and a better understanding of treatment for aging populations may all greatly benefit this population, the entities for whom they work, and the overall economy. For these reasons, national- and state-level policies aimed at improving the conditions and the quality of occupations are important and necessary. Furthermore, these results highlight the importance of spousal warmth behavior, particularly wives’ warmth, in alleviating the negative effects of SWCs on depressive symptoms. These results are important for future interventions and current clinicians to consider as they work to promote affectionate, loving, and caring behavior within couples as a way to protect from the detrimental mental health consequences of SWCs.

Footnotes

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by the U.S. Department of Health and Human Services, National Institutes of Health, National Institute of Mental Health (AG043599).

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