Asian-American elders’ health and physician use: An examination of social determinants and lifespan influences ()
1. INTRODUCTION
1.1. Background
Racial and ethnic minority groups in the United States are growing rapidly. Though often overlooked, Asian Americans are no exception to this unprecedented growth. By 2050, the Asian American population is projected to grow by 213% to 33.4 million people and will represent about 8% of the total US population [1]. Asian immigrants to the United States pose a unique public health challenge given the ethnic diversity within the Asian race and the varied experiences that shape their lives in America. Additionally, as a racial group affected by migration, Asian Americans face cultural challenges to health equity that compound the effects of social determinants of health. Despite rapid population growth, relatively little health research has focused on Asian Americans [2,3]. In order to address the needs of this growing population, further research must investigate the unique health circumstances of Asian Americans and how the considerable diversity within the population impacts health outcomes.
This study focuses on health and physician use among Asian American elders in comparison to Whites, looking at how the aging process affects social determinants of health differently. In addition to age and ethnic background, broader structural and intermediary determinants such as socioeconomic status, psychosocial, and environmental factors likely affect Asian Americans health status. Therefore, this study combines data from the 2005 and 2007 California Health Interview Survey (CHIS) to determine health disparities by ethnic group and then apply a model of social determinants of health to analyze differences.
1.2. Theoretical Framework
Many researchers have documented the relationship between social determinants and health inequities. The Commission on Social Determinants of Health (CSDH) model uses structural and intermediary determinants to explain health inequities [4]. Structural determinants include factors related to socioeconomic status and the broader social opportunity structures that determine access to health care. Social inequities, such as discrimination in the healthcare system, language barriers, and limited access to health care may contribute to higher rates of morbidity and mortality, specifically among racial and ethnic minority groups in the US Intermediary determinants of health include biological and psychosocial factors. Solar and Irwin additionally list access to health care as a major intermediary determinant that is linked with health equity [4]. Health systems are particularly important when thinking about access to care and social participation as these differ by ethnic group and age; for instance, the needs of an older immigrant population may differ from those of a mainstream audience because of various socioeconomic circumstances and cultural beliefs [5].
1.2.1. Physician Use
Receiving care from a physician is one mechanism to improve health [3]. Certainly, many older Asian Americans regularly visit physicians [6], but research with Asian American samples has identified multiple barriers to service utilization, including language difficulties, a fragmented healthcare system, lack of insurance, and lack of knowledge about existing resources [7-9].
1.2.2. Health Equity
The literature on the health of Asian Americans has focused on pan-Asian analyses as well as group-specific studies. Zahran et al. [10] found that Asians/Pacific Islanders reported better health status; fewer physical, mental, and overall unhealthy days; and fewer activity limitation days compared with non-Hispanic Caucasians, Hispanics, American Indians/Alaskan Natives, and nonHispanic African Americans. Yet for specific health conditions, such as diabetes and other chronic illnesses, Asian Americans are at increased risk of morbidity [11- 13].
Although Asian Americans are categorized as one race, there is great diversity in health outcomes among Asian ethnic groups [14-16] in the United States. In his review of Asian health, Dhooper described the health and access-to-care challenges that Asian Americans face. Notably, the foreign-born face access-to-care barriers associated with limited English proficiency, lack of insurance, and low levels of education [17]. Not surprisingly, selfreporting of poor health has been associated with an increased incidence of chronic health conditions and disease. In Sohn’s study of older Korean adults, 69% reported being in poor health, 33% lacked insurance, and 31% had not seen a physician in the past 12 months [18].
1.2.3. Purpose
The widely varying immigration experiences of diverse Asian ethnic groups continue to influence the health statuses of older adults [5]. The life course perspective may be helpful in understanding the differential impact of life experiences, historical events, transitions, and developmental trajectories across the life span of Asian Americans [19] because it posits that individual aging experiences are differentiated by sociohistorical factors, opportunity structures, and life events [20,21]. In particular, the life course perspective provides an overarching framework to explain variations in the aging process [21,22], wherein the differential experiences of particular Asian ethnic groups and the effects of aging are related to physician use and health equity.
While the literature has documented health inequities throughout the lifespan, little research has examined how the aging process differentiates health outcomes in later life among Asian Americans. To address this knowledge gap, this study applies the CSDH model to examine the health and physician utilization use of older Asian immigrants. In particular, this study seeks to address the following questions:
1) How does the health of older Asian Americans compare to that of non-Hispanic Whites?
2) To what extent are there differences in health and physician use between Asian ethnic groups and nonHispanic Whites?
3) What are the joint effects between age and ethnicity on the health and physician use of older Asian American immigrants?
2. METHODS
2.1. Data Collection
This study used publicly available data derived from the 2005 and 2007 versions of the California Health Interview Survey (CHIS). Conducted by the Center for Health Policy Research at UCLA, the CHIS is a cross-sectional study of California residents’ health and access to care. The CHIS is a random-digit-dial telephone survey that uses a two-stage sampling procedure. More Asian Americans live in California than in any other state, and combining two CHIS years enables this study to have the statistical power to focus on interethnic differences among older Asian American adults. The survey instrument was translated into a number of Asian languages, including Cantonese, Mandarin, Korean, Vietnamese, and Khmer. The overall response rates were consistent with other health surveys, ranging from 27% in 2005 to 21.1% in 2007 [23,24].
2.2. Participants
For the purposes of this study, only Asian and White respondents over the age of 65 at the time of the surveys were included in the sample. Respondents who selfidentified as Asian were included in this study if they were Chinese, Filipino, Korean, or Vietnamese. A total of 1340 adults responded to the 2005 CHIS, while 2085 responded to the 2007 CHIS. The local IRB approved the protocols for this study.
2.3. Measures
2.3.1. Dependent Variables
General health. Respondents to the CHIS were asked: “Would you say that in general your health is excellent, very good, good, fair, or poor?” The item was used as an ordinal variable.
Physician use. One item on the CHIS was used to measure physician utilization. Respondents were asked, “How many times have you seen the doctor in the past 12 months?” The responses to the item were dichotomized such that any contact with a physician in the past 12 months was coded as “yes.”
2.3.2. Independent Variables
Race/ethnicity was used as the independent variable. The variable was categorized as Chinese, Filipino, Korean, or Vietnamese. Non-Hispanic Whites were the reference group.
2.3.3. Covariates
2.3.3.1. Structural Determinants Based on the CSDH framework, age, gender, marital status, English proficiency, and educational attainment were used as structural determinants of health. Marital status was categorized into three groups: divorced/separated/widowed and never married, with married as the reference group. English proficiency, a continuous variable in this study, was measured by a single item: “How well do you speak English?” Responses ranged from well to not well, with only English as the reference. Educational attainment (less than high school, high school graduate, and some college), insurance status, and poverty level, as defined in the CHIS, were used as economic controls. Respondents were also asked to indicate how many years they had been in the United States (less than 15 years, or 15 years or more).
2.3.3.2. Intermediary Determinants The CSDH framework conceptualizes health and psychosocial factors as intermediary determinants of health. Accordingly, diagnosis of diabetes or cardiovascular disease, and mental health distress were used as the intermediary determinants. Mental health distress was measured using the K-6 scale. The six-item inventory assesses the prevalence of negative feelings in the past 30 days by asking the following questions: 1) “How often during the past 30 days did you feel nervous—would you say all of the time, most of the time, some of the time, a little of the time, or none of the time?” 2) “During the past 30 day, about how often did you feel hopeless?” 3) “During the past 30 days, about how often did you feel restless or fidgety?” 4) “How often did you feel so depressed that nothing could cheer you up?” 5) “During the past 30 days, about how often did you feel that everything was an effort?” 6) “During the past 30 days, about how often did you feel worthless?” Responses to the six items were summed to obtain a composite score (range = 0 to 24) that was used as a covariate. The Cronbach’s coefficient alpha for the six items was 0.84.
2.4. Analyses
Univariate analyses were used to develop a basic understanding of the factors that affect health and physician use among older Asian American and non-Hispanic Whites. Additionally, bivariate analyses were used to examine associations among the variables. Separate logistic regression models were tested for physician use and overall health. All analyses applied replicate weights to account for complex sampling and were conducted using SAS 9.2 software [25].
3. RESULTS
Table 1 provides an overview of the sociodemographic characteristics of the study sample. A greater percentage of the respondents were female (58%) and married (58%). Among the Asian ethnic group, Chinese respondents (16.8%) were the largest subgroup, followed by Filipinos (13%) and much smaller percentages of Korean and Vietnamese adults. Only 34% of respondents reported that they spoke English well, despite nearly 40% indicating some form of college education and a substantial 88% having lived in the United States for 15 or more years. A resounding majority of the sample indicated having health insurance (97.69%) and having seen a doctor in the last 12 months (88%). Finally, 71% of the adults in this sample self-identified as being in good health.