Abstract IA30: Modeling of socioeconomic wellbeing, follow-up care communication, stress appraisal, coping, and physical functioning among Chinese and non-Hispanic white breast cancer survivors

Background: Minority and immigrant cancer survivors have poorer physical functioning than non-Hispanic Whites (NHWs) and US-born survivors. However, little research has taken a cultural perspective to understand whether there are different stress and coping processes among different cultural groups, which lead to different physical functioning outcomes. Chinese culture is oriented by collectivism, emphasizing interdependence, which induces different cancer concerns from NHWs' concerns. First, Chinese survivors are more likely to express worry about the burden of their disease on their families due to cancer-associated threats (e.g., losing productivity and negating family wellbeing and economic security), whereas NHWs more often express concerns about the loss of independence. These concerns (perceived severity) about family and independence are likely heightened when survivors lack medical and social capital to obtain care in terms of socioeconomic wellbeing, consequently lowering their sense of control of the illness. Emotional stress is negatively related to physical health. This negative relationship is likely to be stronger among Chinese than NHWs because the former has poorer socioeconomic wellbeing plus feels guilty for burdening their families. Second, Chinese culture places value on physician authority over patient autonomy. Chinese survivors usually manifest their respect to physicians through compliance--less expression of their medical needs and requests of resolving their symptoms--consequently making their physical problems unresolved and becoming less satisfied with communication with physicians. Hence, it is likely that communication with physicians is particularly likely to affect health of Chinese cancer survivors. Very little research has examined whether socioeconomic wellbeing and follow-up care communication influence cancer survivors' stress appraisals (i.e. perceived severity and control), coping, and physical functioning, and whether these relationships vary by cultural groups.

Objectives: Guided by the transactional model of stress-coping and vulnerability model, we tested the hypothesis that the impact of socioeconomic wellbeing and follow-up care communication on physical functioning is mediated by stress appraisal and coping variables in both groups, and that this pathway is more robust for Chinese survivors compared with NHWs.

Methods: We enrolled Chinese and NHW breast cancer survivors from California's 2008-2011 cancer registry data. They were aged 21 and older, diagnosed with primary breast cancer at stage 0-III, had completed primary treatment for 1-5 years, and had no recurrence. A total of 436 survivors (220 Chinese and 216 NHWs) completed an hour-long cross-sectional survey assessment via telephone. We interviewed Chinese survivors in their preferred languages; 77% of them were interviewed in Mandarin or Cantonese. Self-reported physical functioning was measured by the short form of patient reported outcomes measurement information system (PROMIS). Independent variables including socioeconomic well-being, communication with follow-up care physicians, stress appraisal, and engagement and disengagement coping were assessed. Counts of patients' self-reported side effects from breast cancer treatment and comorbid conditions were also assessed. Descriptive analysis was conducted to examine factors explaining the physical functioning outcome. Path analysis was run to test the hypothesis of mediation for each ethnic group. Standardized path coefficients were reported. Higher comparative fit index (CFI ≥.95) and lower root mean-square error of approximation (RMSEA <.06) indicated a good model fit to the data. A Wald test was run to test invariance among paths between the two ethnic models.

Results: Chinese survivors, mainly low-acculturated, have lower physical functioning than NHW survivors after controlling for comorbidity, cancer stage, and time since diagnosis (p=.01). Chinese survivors also had poorer socioeconomic wellbeing, follow-up care communication, higher perceived severity, and lower perceived control over breast cancer care than NHWs (all p<.05). Regardless of ethnicity, physical functioning was directly related to comorbidity, treatment side effects, and socioeconomic wellbeing (p<.05). Different from NHW survivors, Chinese survivors' perceived control was directly related to physical functioning (standardized path coefficients=.19, p<.01), after adjusting for covariates. In the Chinese path model (CFI=.95, and RMSEA=.05 with 90% CI=0.00, 0.09), follow-up care communication was not directly related to physical functioning, but it was directly related to perceived control which in turn predicted physician functioning (p<.05). Perceived control was also a mediator of the association of side effects and socioeconomic well-being with physical functioning (both p<.05). In contrast, follow-up care communication in the NHW model (CFI=.98 and RMSEA=.05 with 90% CI: 0.00, 0.07) was not significantly related to perceived control and physical functioning. There were no significant mediation effects found in the NHW model. Disengagement and engagement coping were not significantly related to physical functioning for both Chinese and NHW groups. Moreover, most of the regression paths for the two groups were invariant with the exception of the relationship between socioeconomic wellbeing and engagement coping.

Conclusion: Our study provided evidence that socioeconomic wellbeing affects physical functioning across ethnic groups. The ability to afford care and having access to quality care is essential to physical wellbeing. The results also supported our hypothesis that the quality of communication with follow-up care physicians is more salient to Chinese survivors' perceived control over breast cancer care, which directly explains their physical functioning. These findings are consistent with our prior qualitative findings that Chinese immigrants felt more insecure about their financial stability to afford care, perceived greater negative impact on their families' wellbeing, and were less assertive to ask physicians to treat their symptoms than NHWs. These emotional and communication vulnerabilities, taken together with their lack of cultural and linguistic resources for accessing care, significantly weaken Chinese's evaluation of control. Poor socioeconomic wellbeing and communication are likely to contribute to higher numbers of self-reported side effects and comorbidity, all of which explain individual variation in physical wellbeing. In short, the pathways we identified have gone beyond a conventional stress-coping model to explain ethnic differences in physical functioning. Indeed, they have advanced our understanding of survivorship care needs and issues among cancer survivors from different cultural backgrounds. Asian Americans are the fastest growing population in the US and their breast cancer incidence rates are steadily increasing. A culturally comprehensive mechanism to guide intervention approaches will be essential to effectively reduce health disparities experienced by this growing survivor population.

Citation Format: Judy Huei-yu Wang, Rena J. Pasick, Scarlett Lin Gomez, Jeanne S. Mandelblatt, Roger L. Brown, Laura Allen, Yulia Chentsova, Ellen Huang, Marc D. Schwartz. Modeling of socioeconomic wellbeing, follow-up care communication, stress appraisal, coping, and physical functioning among Chinese and non-Hispanic white breast cancer survivors. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr IA30.