Protective buffering as a mediator of depressive symptoms in women with fibromyalgia
Background/Framework: Fibromyalgia is a common chronic pain illness with a 6:1 female/male predisposition (Lawrence et al., 2008). In addition to daily pain, patients with fibromyalgia have three times the odds of experiencing an episode of major depression as the general population (Fuller-Thomson, Nimigon-Young, & Brennenstuhl, 2012). Drawing upon the developmental-contextual model of couples coping with chronic illness (Berg & Upchurch, 2007), we hypothesized that, in addition to chronic pain, interpersonal factors (relationship quality, social support, and protective buffering) would influence depressive symptoms in women with fibromyalgia.
Methods: Using structural equation modeling, we conducted a secondary analysis of data from 204 women with fibromyalgia in order to simultaneously model the mediation effect of protective buffering in the two relationships of interest–pain and depressive symptoms; relationship quality and depressive symptoms–using a partially latent structural regression model.
Results: The final model provided a good fit to the data (χ2 test of model fit = 12.38, p = .336; comparative fit index = .995; Tucker-Lewis index = .991; root mean square error of approximation = .025, 90% CI: .00, .08; χ2 (20) = 314.33, p < .0001; standardized root mean square residual = .041). Greater pain severity was related to more protective buffering (β = 0.45, p = .004, 95% CI = .14, .77), and more protective buffering was related to greater depressive symptoms (β = 0.71, p = .003, 95% CI = .24, 1.18). After accounting for the mediating effect of concealment, there remained a direct relationship between pain and depressive symptoms (β = 1.55, p < .001, 95% CI = .78, 2.32), but the indirect effect of pain through concealment on depressive symptoms was significant (β = .32, p = .04, 95% CI = .02, .62). Thus, protective buffering partially mediated the relationship between pain and depressive symptoms. Relationship quality was inversely related to protective buffering (β = -10.57, p < .001, 95% CI = -13.22, -7.92), and was not directly related to depressive symptoms (β = -4.43, p = .30, 95% CI = -12.76, 3.91). However, the indirect effect of relationship quality through concealment on depressive symptoms was significant (β = -7.47, p = .004, 95% CI = -12.53, -2.41). Thus, concealment fully mediated the influence of relationship quality on depressive symptoms. Additionally, higher levels of social support from friends was linked to greater relationship quality (β = .79, p < .001, 95% CI = .49, 1.13), and also inversely associated with depressive symptoms (β = -.54, p < .001, 95% CI = -.75, -.33).
Implications: These results add compelling evidence that interpersonal factors are influential on depressive symptoms. Nurses assessing for risk factors of depression among women with fibromyalgia should take into account the patients’ spousal relationship and other social support systems, as well as the patients’ method of communicating symptoms of their illness to the spouse (i.e. protective buffering).