Understanding general and specific connections between psychopathology and marital distress: A model based approach

A substantial body of research now supports the association between marital distress and psychopathology (Whisman, 2007; Whisman & Bruce, 1999; Whisman, Uebelacker, Tolejko, Chatav, & McKelvie, 2006b; Whisman, Uebelacker, & Weinstock, 2004). For instance, there is a robust and well-replicated association between marital discord and major depression; a meta-analysis of 26 cross-sectional studies found an effect size of .42 for women and .37 for men (Whisman & Uebelacker, 2003). Low levels of marital satisfaction have also been linked with anxiety disorders (Markowitz, Weissman, Ouellette, Lish, & Klerman, 1989; McLeod, 1994), alcohol use disorders (Homish & Leonard, 2007; Leonard & Eiden, 2007; Whisman, Uebelacker, & Bruce, 2006a), drug use disorders (Fals-Stewart, Birchler, & O'Farrell, 1999; Homish, Leonard, & Cornelius, 2008; Newcomb, 1994), and personality disorders (South, Turkheimer, & Oltmanns, 2008; Whisman & Schonbrun, 2009). Of note, even though many different clinical disorders show substantial rates of comorbidity (Brown, Campbell, Lehman, Grisham, & Mancill, 2001; Dolan-Sewell, Krueger, & Shea, 2001; Kessler, Chiu, Demler, & Walters, 2005b), or non-random overlap that cannot be explained by chance alone (Lilienfeld, Waldman, & Israel, 1994), research examining associations between marital distress and psychopathology rarely addresses how comorbidity might affect these links. In one exception, Whisman (1999) used the National Comorbidity Survey sample to compare associations between 13 different disorders and marital dissatisfaction, both before and after covarying for presence of other disorders. Without covarying for comorbidity, marital discord was related to 7 of 12 specific disorders for women and 3 of 13 disorders for men; only depression and PTSD (for women) and dysthymia (for men) were significantly associated with marital distress after partialling out other disorders. Similarly, the association between anxiety and marital distress is lessened (Whisman, et al., 2004) or non-significant (Uebelacker & Whisman, 2006) when depressive symptoms are included in the model. South and colleagues (2008) found support for significant associations between marital adjustment and overall levels of personality disorder (PD) symptoms, but few unique associations with symptoms of specific PDs, possibly because they partialled out all other PD symptoms when examining each disorder individually. Thus, while the literature on comorbidity and marital satisfaction is somewhat more limited, it suggests that comorbidity is an important factor in understanding how mental disorders are connected to marital distress. The present study builds on this prior research by examining the specificity and generality of relations between marital distress and different types of mental disorders. Instead of attempting to covary the effects of clinical disorders to examine unique associations, we utilize Structural Equation Modeling (SEM), which has the advantage of minimizing the impact of bias due to unreliability and thus reducing Type I error rate (Zinbarg, Suzuki, Uliaszek, & Lewis, 2010b). We frame our research in light of a dimensional-spectrum model of clinical disorders (Kendler, Prescott, Myers, & Neale, 2003; Krueger, 1999; Krueger & Markon, 2006). A spectrum model explains the high levels of comorbidity among different mental disorders as a function of the way disorders are empirically connected. With regard to common mental disorders, phenotypic and behavior genetic research supports the existence of two latent dimensions: an Internalizing (INT) factor, which subsumes two lower-order factors of Distress (major depression, generalized anxiety) and Fear (phobias, panic attack); and a latent Externalizing (EXT) factor indicated by substance use disorders, conduct disorder, and adult antisocial behavior (Griffith, et al., 2010; Hettema, Neale, Myers, Prescott, & Kendler, 2006; Kendler, et al., 2003; Krueger, 1999; Krueger, Caspi, Moffitt, & Silva, 1998; Krueger, et al., 2002; Prenoveau, et al., 2010; South & Krueger, 2008; Vollebergh, et al., 2001). Given this model, in which different types of clinical disorders are understood as being linked to shared underlying temperamental antecedents (Clark, 2005; Zinbarg, et al., 2010a), a potentially useful analysis would consider and model both general and specific connections between mental disorders and marital distress. Marital distress is certainly a correlate of specific forms of psychopathology (Beach, Katz, Kim, & Brody, 2003; Overbeek, et al., 2006; Whisman, 2007; Whisman & Bruce, 1999; Whisman, et al., 2006a). Low levels of marital satisfaction have also been linked to broader classes of disorders, including mood, anxiety, and substance use disorders (Whisman, 1999, Whisman, 2007). In a recent study, Humbad and colleagues (2010) found that both individual externalizing syndromes (i.e., conduct disorder, antisocial behavior, substance use) and a composite of these various syndromes were negatively related to marital adjustment, suggesting that externalizing psychopathology per se is an individual vulnerability to marital distress. Left unanswered in that study was the question of whether marital dysfunction was attributable to whatever is shared in common between externalizing disorders, or if each syndrome has unique and specific effects on the marital relationship after accounting for overall levels of externalizing pathology. Thus, we do not yet know if marital discord is linked to the general INT and EXT domains, the residual aspects of certain forms of INT and EXT psychopathology, or a combination of both general and specific relations. Figure 1 presents a simplified model of the full set of associations estimated in the current study. Our first research question is whether common forms of psychopathology, which have individually been linked to martial distress previously, can be modeled as higher order factors which are associated with marital adjustment. As shown, observed indicators X, Y, and Z (e.g., depression, anxiety, social phobia) may be related to marital distress through latent factors of psychopathology. Figure 1 Simplified model outlining pathways between latent factors representing wives' and husbands' psychopathology and marital distress. Marital distress factors were comprised of subscales from the Dyadic Adjustment Scale, represented here as observed indicators ... Also shown in Figure 1, there are paths from the psychopathology factors for both husbands and wives to both self- and spouse's marital adjustment factor. Kenny and colleagues (Kenny, 1996; Snjiders & Kenny, 1999) have articulated the distinction between actor effects and partner effects. An actor effect is the influence of the target's own behavior on their own satisfaction (e.g., wife's depression affecting her own satisfaction), while the partner effect is the influence of one's spouse on own satisfaction (e.g., husband's depression affecting wife's rating of satisfaction). Most research in this area has focused only on actor effects, whether in large community epidemiologic research (e.g., Whisman, 1999) or treatment samples in which the patient often reports lower levels of marital satisfaction (e.g., Fals-Stewart, et al., 1999). By incorporating measures of self- and spouse-report of psychopathology and marital distress, it is possible to estimate directly the importance of spouse's mental health on one's own marital satisfaction, as well as statistically covarying for the fact that couples are often correlated on level of psychopathology (i.e., assortative mating is present for many clinical disorders; Galbaud du Fort, Boothroyd, Bland, Newman, & Kakuma, 2002; Butterworth & Rodgers, 2006; Low, Cui, & Merikangas, 2007). Empirical work to date has found support for actor effects of anxiety (Whisman, et al., 2004), actor and partner effects of depression (Whisman & Uebelacker, 2009; Whisman, et al., 2004), and actor and partner effects of personality disorder symptoms (South, et al., 2008) on marital satisfaction. Our second research question was to estimate actor effects between wives' and husbands' own level of INT/EXT psychopathology and own marital distress (AW and AH in Figure 1), as well as wives' and husbands' own psychopathology and spouses' marital distress (PW and PH in Figure 1). Also directly estimated were the associations between wives' and husbands' marital distress (rMD) and assortative mating for the latent psychopathology factors (rP). Finally, Figure 1 also includes a pathway from the marital distress factor to the residual variance of a psychopathology indicator, an example of understanding the connections between specific aspects of psychopathology and the latent construct of marital adjustment. Previous work has examined associations between more narrow-band forms of psychopathology and marital distress while covarying out comorbid disorders; however, there has been no work to date to examine whether there are associations between marital adjustment and whatever is unique to different types of psychopathology after accounting for the broader spectrums that link these disorders together. Finding significant associations between an overall marital adjustment factor and the residual variances of the clinical disorders subsumed by our latent INT and EXT factors (i.e., the residual correlation, rR, found in Figure 1) would provide tentative evidence of specificity in the transactions between psychopathology and the marital relationship. Conversely, the lack of such associations would suggest that marital distress in the presence of psychopathology may be a function of the impairment caused by the temperament and/or behaviors at the core of the internalizing and externalizing spectrums.