ارتباط بین دوسوگرایی در ابراز هیجانی و علایم افسردگی در بین بازماندگان سرطان پستان چینی

Abstract Objective Ambivalence over emotional expression (AEE) is the conflict between wanting to express emotion yet fearing the consequences of such expression. Recent literature reveals a close link between AEE and depressive symptoms among college students. Although cancer survivors experience intense emotions, few studies have examined the relationship between AEE and depressive symptoms and the underlying mechanisms among cancer survivors. Furthermore, relevant research is absent among Asians, whose culture discourages emotional expression. The present study investigated AEE's associations with depressive symptoms in Asian breast cancer survivors, and examined intrusive thoughts as a mediator. Intrusive thoughts are repetitive and unwanted thoughts about stressful events. We hypothesized that AEE would increase intrusive thoughts which in turn would increase depressive symptoms.

Introduction Breast cancer is the most common cancer in women worldwide. It is estimated that more than 1.6 million new cases of breast cancer occurred among women worldwide in 2010 [1]. Having experienced a serious illness like breast cancer, survivors often face emotional and social problems following cancer diagnosis and treatment [2], [3] and [4]. A review suggests that the prevalence of clinically significant depressive symptoms in cancer patients and survivors exceeds that of the general population [5]. Because cancer diagnoses and treatments often elicit strong emotional responses, and these emotions often accompany cancer survivors' years after treatment, how individuals cope with these emotions may influence their adjustment. For example, a recent prospective study with a nationally representative U.S. sample over a 12-year follow-up found that emotion suppression increases risk of earlier death, including death from cancer [6]. The Asian American breast cancer rate has been the nation's fastest growing [7], however few studies have investigated emotion suppression among Asian American cancer survivors. In Western cultures, open emotional expression tends to be expected [8]. In many Asian cultures, there is a norm of suppressing emotions and concealing private thoughts to avoid damaging harmony with others [9]. Given the different cultural norms, it is imperative to provide empirical evidence on whether it would be beneficial to encourage emotional expression, and how to design interventions to reduce distress among Asian cancer survivors. Among the Asian American populations, Chinese represent a less acculturated immigrant population compared to other Asian ethnic groups such as Japanese and Filipino [7]. Thus, they may be at higher risk of added psychological distress given their immigrant status. The first goal of the present study was to examine whether depressive symptoms were linked with Ambivalence over Emotional Expression (AEE) among Chinese American breast cancer survivors. Healthy Asian Americans have been found to experience more AEE compared to Caucasians [10], which indicates the importance of examining emotion expression/suppression among Asians cancer survivors. AEE is defined as an individual's inner conflict concerning the desire to express emotions yet failing to do so [11]. A number of previous studies have found that higher levels of AEE are associated with significantly higher levels of depressive symptoms in various populations including college students, rheumatoid arthritis patients, and the general population [11], [12], [13], [14], [15] and [16]. There has only been one study investigating the AEE construct in cancer patients. Porter and colleagues studied AEE's associations with pain and quality of life among gastrointestinal cancer patients [17]. They found that patients who were high in AEE engaged in more pain catastrophizing and reported poorer quality of life. Accordingly, it was hypothesized that AEE was positively associated with depressive symptoms among cancer survivors. The second goal of the study was to investigate the mechanisms underlying the link between AEE and depressive symptoms. Pennebaker [18] has proposed that the lack of emotional expression coupled with the desire to express will lead to obsessive thoughts related to the inhibited feelings or event. Cancer survivors commonly report experiencing significant amounts of intrusive thoughts relevant to cancer [19]. Intrusive thoughts are defined by Horowitz [20] as repetitive and unwanted thoughts about stressful events. These thoughts arise when information about traumatic or stressful events is present, and cannot be fully assimilated into an individual's preexisting schemas. Horowitz [21] has argued that intrusive thoughts subside once the individual modifies the preexisting schemas to fully assimilate or accommodate the new information. Successful assimilation (i.e., changing the appraised meaning of the stressful event to make it consistent with preexisting schemas) and accommodation (i.e., modifying preexisting schemas to adjust them to the appraised meaning of the stressful event) of the new information help the individual restore feelings of security. This process may depend on repeated exposure to the traumatic stimuli, reappraisal of the stressors, and the modification of preexisting schemas. Talking about stress and relevant emotions may expose individuals to the trauma, and offer an opportunity to re-evaluate the stressors, and facilitate the assimilation or accommodation of the new information. By being ambivalent about expressing emotions regarding the stressful event, individuals might not be aware of the source of distress which impedes the cognitive processing that is necessary for the assimilation or accommodation to take place. In other words, ambivalence over emotional expression may take away the opportunity for intrusive thoughts to become resolved. Furthermore, inhibition of feelings may also promote unwanted thoughts [22]. Intrusive thoughts are theorized to play a critical role in the development or maintenance of negative emotions [23]. Several studies have shown that intrusive thoughts are positively associated with depressive symptoms [23] and [24]. While there is currently no direct evidence supporting the link between AEE, intrusive thoughts, and depressive symptoms, some research has shown that cancer patients with lower levels of emotional expressivity experienced higher levels of distress caused by their intrusive thoughts [25]. Emotional expression allows the individual opportunities to process the event again as well as the emotions that come with it, which reduces the detrimental impact of intrusive thoughts. This evidence provides further support for the links between AEE, intrusive thoughts, and depressive symptoms. We hypothesized that intrusive thoughts may mediate AEE's positive associations with depressive symptoms. As noted, the goal of the present study is to investigate AEE's associations with depressive symptoms in Chinese American breast cancer survivors, and to examine underlying mechanisms. We propose the following hypotheses: 1. AEE would be positively associated with depressive symptoms and intrusive thoughts. 2. Intrusive thoughts would mediate the relationship between AEE and depressive symptoms.

Results Sample characteristics are shown in Table 1. Descriptive statistics of major variables and Pearson correlation matrix among the major variables are presented in Table 2. All measures demonstrated good internal consistency; alpha coefficients ranged from .81 to .94. Age was correlated with intrusive thoughts. Stage at diagnosis was correlated with depressive symptoms and intrusive thoughts. All the other demographic and cancer-related characteristics (e.g., education) were unrelated to AEE, intrusive thoughts, or depressive symptoms. Thus, only age and stage at diagnosis were controlled as covariates in the following analyses. Table 1. Characteristics of participants (N = 118). N (frequency%)/mean (SD) Demographic variables Age (years) 54.65 (8.61) Marital status Married 85 (72%) Single/separated/divorced/windowed 33 (28%) Education level Middle school or below 19 (16.1%) High school 35 (29.7%) Associate degree 32 (27.1%) College degree or above 32 (27.1%) Employment Full-time employed 34 (28.8%) Part-time employed 17 (14.4%) Unemployed or housewives 55 (46.7%) Retired 9 (7.6%) Others 3 (2.5%) Average annual household income Less than $15,000 38 (32.2%) $15,000–$45,000 28 (23.7%) $45,000–$75,000 21 (17.8%) More than $75,000 19 (16.1%) Unknown 12 (10.2%) Cancer- and treatment-related variables Years since diagnosis 1.35 (1.09) Stage at diagnosis Stage 0 15 (12.8%) Stage I 35 (29.9%) Stage II 49 (41.9%) Stage III 18 (15.4%) Treatment Surgery 111 (94.1%) Radiotherapy 44 (37.3%) Hormone therapy 81 (68.7%) Chemotherapy 76 (64.4%) Table options Table 2. Means, standard deviations, and correlations among major variables. Mean SD (1) (2) (3) (4) (5) 1. Age 54.65 8.61 – 2. Stage at diagnosis 1.60 0.90 − .01 – 3. AEE 1.96 0.90 − .15 .03 – 4. Depressive symptoms 0.75 0.78 − .15 .33*** .45*** – 5. Intrusive thoughts 10.81 7.59 − .19* .19* .44*** .56*** – Notes. *p < .05, **p < .01, ***p < .001. Table options Regression analysis was conducted with depressive symptoms as a dependent variable. Age and stage at diagnosis were entered in Block 1 as covariates. AEE was entered in Block 2 as an independent variable. In Block 1, stage at diagnosis was positively associated with depressive symptoms (β = .32, p < .01), and explained 13% of the variance in depressive symptoms. In Block 2, as hypothesized, a higher level of AEE was associated with a higher level of depressive symptoms (β = .45, p < .001) and explained 20% of the variance in depressive symptoms. The mediating role of intrusive thoughts in the relationship between AEE and depressive symptoms was tested with path analysis. Because the zero-order correlation analyses showed that age and stage at diagnosis were correlated with intrusive thoughts and depressive symptoms, and age and stage at diagnosis were also included in the hypothesized model (Fig. 1). Path analyses revealed the hypothesized mediation model fit well, NFI = .97, CFI = 1.00, GFI = .99, SRMR = .05. AEE had a positive association with depressive symptoms (β = .27, p < .001). AEE also had a positive association with intrusive thoughts (β = .42, p < .001), which had a positive association with depressive symptoms (β = .40, p < .001). That is, AEE was positively associated with depressive symptoms both directly (t = 3.57, p < .001) and indirectly through intrusive thoughts (z = 2.20, p < .05). The results suggested that intrusive thoughts partially mediated the relationship between AEE and depressive symptoms. Mediation analysis for depressive symptoms among Chinese breast cancer ... Fig. 1. Mediation analysis for depressive symptoms among Chinese breast cancer survivors. Notes. Stage at diagnosis was included as a covariate for intrusive thoughts (β = .18, p < .05) and depressive symptoms (β = .25, p < .001), and age was a covariate for intrusive thoughts (β = .13, ns). Stage at diagnosis and age were not included in the figure for clarity. *p < .05, **p < .01, ***p < .001.