1A significant proportion of United States (U.S.) Latinos (54%) reside in U.S.-Mexico border-states, with Mexican Immigrants and Mexican Americans (MI-MA) being the largest subgroup (PHC 2011). When compared to other border-states, California has the largest MI-MA population and largest percentage of non-citizen residents. Of the foreign-born MI in California, only 825,000 are naturalized citizens and nearly 3 million are non-citizens, with a large proportion living on or near the U.S.-Mexico border (CMHI 2010; USMBCC 2010). If current trends remain unchanged, populations in this region will continue growing at a faster rate than the population as a whole in both the U.S. and Mexico (USMBCC 2010).
2Immigration has been the recent focus of intense political debate, with a recurrent theme being the use of public services, including healthcare (Galarneau 2011). Although Latinos are the largest and fastest growing ethnic group in the U.S., they underutilize healthcare, with MI-MA living on the U.S.-Mexico border experiencing greatest disparities (USMBCC 2010, Vargas-Bustamante et al. 2009, Wallace, Gutierrez and Brown 2003). Widespread poverty, unemployment, low educational attainment, high uninsurance rates, a large undocumented population, inadequate public healthcare infrastructure, and a shortage of healthcare providers, are all factors limiting access to healthcare services along the US-Mexico border (USMBCC 2010).
3With the continued rise of healthcare costs, the U.S. Department of and Human Services has emphasized the use of prevention healthcare services among the vulnerable, particularly those with restricted access (HHS 2003). Access to prevention healthcare services in the U.S.-Mexico border may be particularly important given the high prevalence of preventable diseases among MI-MA in this area (USMBCC 2010). Rates for numerous infectious diseases and chronic health conditions including tuberculosis, diabetes, heart disease, obesity, and cervical cancer, are higher among Latinos (including MI-MA) in the U.S.-Mexico border when compared to Latinos on other U.S. areas (Anders 2013, USMBCC 2010). Increasing the use of preventive medical services (e.g., routine check-ups, health screens, immunizations) for MI-MA in this area may be important to facilitate early detection and treatment, which in turn may reduce morbidity and mortality rates, as well as healthcare spending (USMBCC 2010).
4New contribution. Research on the use of routine medical exams on the US-Mexico border among MI-MA varying in legal status is limited. Although the literature has addressed citizenship and authorized status as important determinants (Vargas-Bustamante et al. 2009; Vargas-Bustamante et al. 2010), this study is the first to explore the use of routine medical care (RMC) in this border population. Given existing disparities in the use of healthcare services along the U.S.-Mexico border(USMBCC 2010), the purpose of this study was to explore the association of specific factors (including legal status) and RMC use to better understand patterns of use among MI-MA in this border region.
5Conceptual model. The conceptual model utilized was a version of the Anderson model adapted for studying the homeless population called the Behavioral Model for Vulnerable Populations (Gelberg, Andersen and Leake 2000). Since part of the population in this study is transient, this adapted version of Anderson’s model was relevant (Parchman and Byrd 2001). This model emphasizes three overlapping domains likely to influence healthcare service use: predisposing (demographic and social structure characteristics including legal status); enabling (factors that facilitate/impede healthcare service use), and need, (health status characteristics).
6Design and sample. This cross-sectional study used data collected in 2009 for the San Diego Prevention Research Center (SDPRC) biannual community survey, which assessed various aspects of quality of life and health behaviors of Latinos living on the U.S-Mexico border. Multistage sampling methods were used to select participants. Two hundred census blocks from four high-density Latino communities were randomly selected. From these, 4,123 households were selected at random. To be eligible for participation, the household should have had at least one self-identified Latino adult (age ≥ 18) who lived in the house at least 4 or more days per week. Only one adult was interviewed per household. Nearly 42% of households were eligible, 27% were ineligible (no Latinos living in the household), and 31% were visited but of unknown eligibility (no access). The cooperation rate was 23%. Comparisons using neighborhood characteristics showed participating households were located in neighborhoods that on average, had a lower percentage of home ownership (27.5%) compared to neighborhoods in which households refused participation (31.7%; p ≤ 0.005).
7A total of 397 Latino adults completed the survey, including 392 participants who self-identified as MI-MA. Of these, five were missing data on the outcome of interest (use of RMC) and/or reported immigration legal status; thus, they were excluded from analyses. Results are based on the remaining 387 MI-MA.
8Data collection. Trained bilingual, bicultural research assistants conducted a single home visit for eligibility assessment and a face-to-face interview. Participants could complete the survey in English or Spanish. When available, valid translated versions of measures were used. For non-translated measures, a certified translator was used. As a final step to validation, the entire survey was reviewed and approved by a native Spanish speaker member of the research team. No compensation was provided for participation, and the study was approved by SDSU-UCSD Institutional Review Boards.
9Dependent Variable. RMC use was assessed using the question “About how long has it been since you last visited a doctor for a routine checkup [examen de rutina]? A routine checkup is a general physical exam [examen general de salud], not an exam for a specific injury, illness, or condition.” This question was modeled after the 2008 Behavioral Risk Factor Surveillance Survey (BRFSS)(CDC 2009), and it has been previously used as outcome variable to assess RMC use (Parchman and Byrd 2001). Based on the distribution of data, responses were collapsed into three categories denoting recency in RMC use: “recent” (<1 year), “delayed” (≥1 year, but < 5 years), and “limited” (≥ 5 years including never). Despite limited guidelines available, it has been suggested that annual RMC is useful to identify asymptomatic diseases early, obtain immunizations, and improve patient-physician relationships (Merenstein, Daumit and Powe 2006). Hence, “recent use” was used as the referent category.
10Predisposing factors. These included demographics (age, gender), social structure variables (marital status, education, household size) and immigration characteristics (years in U.S., acculturation, legal status). Demographic questions were modeled after the 2008 BRFSS and the U.S Census Bureau (CDC 2009; USCB 2009). Acculturation was assessed using the Bidimensional Acculturation Scale for Hispanics (BAS), which is a 12-item measure that produces two scores: Hispanic and Anglo domain (Marin and Gamba 1996). In this study, only the Anglo domain was used (continuous score ranging from 1-4), with higher scores denoting higher acculturation to the English language. The BAS has good psychometric properties, and works well with MI-MA (Marin and Gamba 1996). Legal status was assessed using questions from the 2007 Boston Metropolitan Immigrant Health & Legal Status Survey (BM-IHLSS). Three legal status categories were created (U.S. citizens, legal residents, and undocumented/temporary residents) (Marcelli, Holmes and Estrella 2009). Given the small sample size and consistent with previous studies, temporary residents (n=17) were combined with the undocumented (n=61) (Ortega et al. 2007). Temporary residents were similar in important demographic characteristics (age, gender, employment, insurance status, poverty level, marital status, and acculturation) when compared to the undocumented. Nevertheless, any bias that the temporary residents may have introduced to the undocumented category was expected to be positive resulting in more conservative comparisons (Ortega et al. 2007).
11Enabling factors. These were assessed using economic factors (poverty level, employment, insurance status, and cost as a barrier to healthcare service use), as well as residence stability (years at current residence), social network, dispositional trust (confianza), and perceived discrimination. Social network was assessed using two continuous variables from the Social Network Scale of the 2007 BM-IHLSS (Marcelli, Holmes and Estrella 2009). The first denoted size of a respondent’s immediate social network (up to 5 people), and the second measured instrumental social support. This, encompassed the concrete ways that people assist each other (e.g., number of times a person has helped you with transportation, family, financial, health, housing or some other problems during the past 12 months?). This scale has been previously used with Latinos (Marcelli, Holmes and Estrella 2009). Trust or confianza was assessed using the Trust Subscale of the Social Capital Assessment Tool (Subramanian, Kim and Kawachi 2002). This 7-item scale assesses how much an individual trusts a variety of groups that he/she interacts with. Responses ranged from 4=a lot to 1=not at all, and this scale has been previously used with Latinos (Marcelli, Holmes and Estrella 2009). Perceived discrimination was assessed using a dichotomous variable (Yes/No) based on responses to the question “within the past 30 days, have you felt emotionally upset, for example angry, sad, or frustrated, as a result of how you were treated based on your race?” (CDC 2009).
12Need factors. These were assessed using self-reported presence of a chronic illness (Yes/No), mental health status, and having crossed the border for medical reasons within the past month (Yes/No). Mental health status was assessed using the Patient Health Questionnaire-9 (PHQ-9) (Kroenke, Spitzer and Williams 2001). This 9-item scale uses a continuous score (range 1 to 27) to assess for symptoms of depression (1-4=minimal; 5-9=mild; 10-14=moderate; 15-19=moderately severe; 20-27=severe), and it is valid for use with Latinos (Merz et al. 2011).
13Proposed Statistical Analyses. Analyses were conducted using SPSS, Version 19.0. Descriptive statistics were generated for all study variables. Bivariate associations were examined between study variables and RMC use. For parsimony, only variables significantly associated (p ≤ .05) with the outcome of interest in bivariate analyses were included in multivariate models. Three multivariate logistic regressions were performed to determine the independent association between predisposing, enabling and need variables and RMC use. The first model tested the relevance of the aforementioned factors to recent versus limited RMC use, the second compared recent versus delayed use, and the third compared delayed versus limited use. In all models, sequential analyses were used to assess the relative contribution of predisposing (step 1), enabling (step 2), and need (step 3) characteristics to RMC use.
Table 1. Predisposing, enabling and need characteristics associated with RMC use.
Legend : 1Recent RMC = Use of routine medical care < 1 year ago. 2Delayed RMC = Use of routine medical care ≥ 1 year ago, but < 5 years. 3Limited RMC = Never used routine medical care or used it ≥ 5 years ago. 4Mean BAS score = Mean acculturation score as measured by the Anglo domain of the Bidirectional Acculturation Scale for Hispanics (BAS) (21). *p < .05; **p < .01; ***p < .001
Table 2. Sequential logistic regression to differentiate recent (< 1 year ago=0) versus limited (never or ≥ 5 years ago=1) use of RMC.
Legend : a Reference category: Citizens. *p < .05; **p < .01; ***p < .001
Table 3. Sequential logistic regression to differentiate recent (< 1 year ago=0) versus delayed (≥ 1 year, but < 5 years =1) use of RMC.
Legend : a Reference category: Citizens. *p < .05; **p < .01; ***p < .001
14Sample characteristics. Descriptive statistics are presented in Table 1. The sample was predominantly female with an age range of 18 to 89 years. The mean age was 44 years (SD=16.9). More than half had less than a high school education and were unemployed, and almost half lived in poverty. Fewer than half were uninsured, roughly a quarter noted that cost limited their healthcare service use in the past year, and more than a third reported having crossed the border to Mexico to seek medical services/medications within the past year. Most participants answered the survey in Spanish (89%) and were moderately acculturated based on language use. No significant differences in RMC use were observed between respondents who answered the survey in English versus Spanish (p = .11). Half of the participants were citizens (US born or naturalized), with the rest being permanent legal residents (31%) or undocumented/temporary residents (19%). Nearly half reported having a chronic health condition, but on average minimal symptoms of depression were reported (M=4.3, SD=4.7). Two-thirds reported having recent RMC use, 21% reported delayed use and 12% reported limited use. Undocumented immigrants reported the least use of recent RMC, with citizens reporting the most recent use. Undocumented immigrants reported the most limited use of RMC.
15Characteristics associated with RMC use. Results of multivariate analyses comparing recent versus limited use, and recent versus delayed use are presented in Tables 2 and 3 respectively. For parsimony, results from analysis comparing delayed versus limited use are not included in a table, but discussed in the results. All models exceeded the minimum number of cases needed for unbiased estimates (Vittinghoff and McCulloch 2007).
16In the model comparing recent versus limited RMC use, the model with the predisposing factors was statistically significant, 2 (6, N=211 = 28.37, p < .001), and accounted for 21.4% of the variance. After adding enabling characteristics, the model remained statistically significant accounting for 30.2% of the variance. The addition of need characteristics did not improve model fit. In the full model, being a man, having undocumented legal status versus citizenship, and having experienced cost as a barrier to the use of healthcare services were significantly associated with limited use of RMC when compared to recent use, after controlling for relevant covariates.
17In the model comparing recent versus delayed RMC use, the model with only predisposing factors was not significant, 2 (6, N=241= 9.85, p = 131), and accounted for little variance (5.8%). In the full model, the addition of enabling and need characteristics significantly improved model fit and increased the explained variance (21.3%). Being a man, being uninsured, having experienced cost as a barrier to the use of healthcare services, reporting more trust, and not having a chronic illness were significantly associated with delayed use of RMC when compared to recent use, after controlling for relevant covariates.
18In the model comparing delayed versus limited RMC use, the model with predisposing factors was statistically significant, 2 (6, N=98) = 14.01, p = .03), and accounted for 18.5% of the variance. In the full model, the subsequent addition of enabling and need factors increased the explained variance (23.6%). Being undocumented when compared to having citizenship was significantly associated with limited use of RMC when compared to delayed use. Specifically, those reporting undocumented status were 8.94 times more likely to report limited versus delayed use of RMC after controlling for relevant covariates (95% CI=1.70, 47.07, p = .01).
19This study identified factors, including immigration legal status, associated with the use of RMC among MI-MA on the California-Mexico border. When compared to national estimates for MI-MA in the U.S., participants in this study differed on several factors likely to influence the use of preventive healthcare services, including this sample being older, having lower educational attainment, higher unemployment and a higher percentage living in poverty (Motel and Patten 2012). This suggests that MI-MA living in this border region may face a significant number of barriers, which may preclude use of RMC in this community. Noteworthy is that this sample is predominately female; thus, the identified patterns of utilization mostly pertain to MI-MA women in this region.
20No studies with similar populations have assessed the use of RMC in a manner comparable to this study; thus, direct comparison of estimates was not possible. Nevertheless, when comparing healthcare service use by immigration legal status, this study showed patterns consistent with previous studies (Fuentes-Afflick and Hessol 2009). Specifically, citizens were more likely to report recent use of RMC, with the undocumented having the lowest utilization. Noteworthy is that in additional sensitivity analyses, naturalized citizens were more likely than U.S. born citizens to report recent use (data not shown). Although factors other than naturalization likely influence the use of preventive healthcare services, it is possible that legalization could facilitate access to resources (e.g., insurance) and development of skills (e.g., English proficiency) likely to increase access to preventive healthcare use. Longitudinal studies are needed to explore how changes in immigration legal status may influence access to resources and skills that facilitate the use of preventive healthcare services.
21Important predictors of the use of RMC were identified in this study. Consistent with previous studies, being undocumented was associated with limited use of RMC, even after controlling for economic factors and insurance (Berk et al. 2000). Previous studies have shown fear of deportation and limited English proficiency as barriers to the use of healthcare services among the undocumented (Berk et al. 2000; Berk and Schur, 2001). This concern may be prevalent given current ambivalence and uncertainty on immigration policies (Galarneau 2011). Noteworthy in this study is that undocumented status was relevant for distinguishing between those with recent versus limited RMC use, but not in differentiating between those with recent versus delayed use. This could suggest that once undocumented immigrants identify a source of care that is accessible and where they feel safe, immigration legal status may no longer impede the use of preventive services, but instead uninsurance and financial limitations may present greater barriers. This emphasizes the importance to continue providing support and funding to safety net providers, such as federally qualified healthcare centers, which provide accessible and affordable healthcare to marginalized immigrants (including the undocumented), who otherwise delay care until emergency services are necessary. Facilitating access to affordable and safe preventive healthcare through safety net providers, health fairs, and programs led by Community Health Workers (CHW), may be a viable way to prevent, identify and treat disease early among marginalized immigrants, which in turn may reduce the use of emergency care and related costs (D-Emilia and Suplee 2012).
22Previous studies with MI-MA have found insurance and cost to be strong predictors of preventive healthcare service use (Vargas-Bustamante et al. 2010; Parchman and Byrd 2001; Leybas-Amedia, Nuno and Garcia 2005). This study supports these findings. Differences in insurance status across MI-MA varying in immigration legal status may contribute to even greater within group disparities that may preclude the use of preventive healthcare services. Bivariate analysis in this study showed significant differences existed in insurance coverage by immigration legal status, with citizens more likely to be insured (70%) when compared to legal residents (58%) and the undocumented (25%). Chronic uninsurance is common and more prevalent among MI-MA when compared to other Latino subgroups (Vargas-Bustamante, Hai-Gang and Ortega 2009), and socio-economic factors, including economic disadvantage and transient lifestyles, provide the most common explanation for the disparity (Goldman, Smith and Sood 2005). The Patient Protection and Affordable Care Act (ACA) (HHS 2012), signed into law in 2010, is intended to expand access to health insurance coverage for the poor and uninsured in the US. Yet, the ACA specifically excludes undocumented immigrants from obtaining access to health insurance, even if they are willing to pay for their own health policy. It is estimated that after full implementation of the ACA, undocumented immigrants in California will account for almost half (41%) of the uninsured population in this state, and at least a third of the uninsured in others states with high concentration of undocumented immigrants (i.e., Arizona, Florida, North Carolina, Texas) (Wallace et al. 2013). Revisions to current health policies, including those at federal and state levels, as well as the development of new alternatives to facilitate access to health insurance for marginalized immigrants is needed to ameliorate the burden faced by safety-net providers in areas with high concentrations of uninsured undocumented immigrants. A potential alternative to consider is to allocate additional funding to support safety-net providers in high-density Mexican and Central-American immigrant communities, as well as provide undocumented immigrants with opportunities to purchase low cost health insurance, which should include the provision of specific prevention health screens. Also, allowing for binational insurance coverage that pays for high-cost services in Mexico, but provide coverage for primary care in the U.S. could be another way to facilitate access to insurance coverage for the undocumented population (Wallace et al. 2013).
23Another relevant finding in this study is that participants who reported having a chronic health condition were more likely to report recent rather than delayed RMC use. Awareness of a health condition may increase awareness of the need for having annual checkups to prevent worsening of symptoms. It is common among Latinos to seek or postpone medical care until symptoms are present, which are usually severe (Leybas-Amedia, Nuno and Garcia 2005). Early and clear diagnoses of illnesses, particularly for those that are asymptomatic, may be valuable to increase adherence to periodic use of RMC in this population. Given the high prevalence of chronic health conditions such as diabetes, heart disease and obesity, as well as high rates of preventable cancers in this population, it is important to develop contextually and culturally-sensitive campaigns to promote compliance with recommended health screenings in this population (USMBCC 2010).
24Several studies show trust in healthcare providers to be a predictor of healthcare service use (Larkey et al. 2001). However, this study is the first to explore trust or confianza as a general disposition associated with healthcare service use. In this study, respondents with higher levels of confianza were likely to delay RMC use when compared to those with recent use. Although this association may seem contradictory, it is possible that the association between confianza and preventive healthcare service use could be mediated by self-rated health and optimism. Previous research shows that individuals with a greater disposition to trust report higher levels of self-rated health and wellbeing (Kim, Sinco and Kieffer 2007; Mohseni and Lindstrom 2007; Molina, Zambrana and Aguirre-Molina 1994; Schwarzer 1994). In other words, individuals with a higher disposition to trust may be likely to have an over-optimistic view of their health and a reduced risk perception for illness, which may invalidate a need for periodic use of medical check-ups. The need for periodic medical check-ups may be further undermined by a tendency to use healthcare services mostly in the face of symptoms, rather than for prevention (Larkey et al. 2001). Another way in which confianza may contribute to delayed RMC use may be related to the cultural belief of fatalism, which emphasizes that events are predetermined by fate; thus, inevitable (Larkey et al. 2001; Molina, Zambrana and Aguirre-Molina 1994). A belief in predetermined fate may discount the importance of periodic RMC to ensure health. The role of trust and its association to perceived-health and use of RMC in this population is not well understood; thus, additional studies are needed.
25Limitations. This study has some limitations. First, source of care was not measured. Having a usual source of care is associated with increased utilization (Vargas-Bustamante et al. 2009; Vargas-Bustamante et al. 2010). Nevertheless, other important factors were identified (e.g., undocumented status, confianza). Second, this study relied on self-report and retrospective data, which may have led to over/under estimation of RMC timeframe. Third, disclosure of legal status is a sensitive matter; thus, some respondents, particularly the undocumented, may have misrepresented their legal status, which may result in more conservative estimates. Fourth, the question used to assess use of RMC may not adequately capture the use of less-traditional prevention healthcare services common among this population (e.g., homeopathic, complementary/alternative medicine). Future studies should consider assessing the use of less-traditional healthcare prevention services. Fifth, the 23% cooperation rate may reflect a self-selection bias. Nevertheless, this survey used multistage sampling to minimize threats to external validity, and as a result, the sample included adequate variation in the immigration status of participants. Also, this sample was predominately female; thus, this study may not adequately represent level of RMC use among MI-MA males in this region. A similar study with a larger sample of men is necessary to assess the generalization of study findings. Finally, these findings might not generalize to MI-MA living in non-border regions, as well as to other non-Mexican populations along the border and living in the U.S. Given the use of cross-sectional data, causality cannot be inferred.
26MI-MA living on the California-Mexico border are at significant risk for developing health problems; RMC use is suboptimal (USMBCC 2010). To improve use, outreach efforts should target MI-MA of lower socio-economic status, particularly the undocumented and uninsured. This may require the support of safety net providers, as well as events such as health fairs and periodic health screenings at shelter and federally qualified healthcare centers to facilitate access. In addition, disseminating information to the community in a way that is contextually and culturally sensitive about the importance of periodic healthcare services may be helpful, as well as advocating for the development of policies favoring access to affordable healthcare and insurance regardless of immigration legal status. All of the aforementioned recommendations require collaboration between community-based organizations, healthcare providers, researchers and those in charge of developing and influencing economic and public policy. Addressing the unique healthcare needs of MI-MA in the U.S.-Mexico border region is complex, but it is in the best interest of both nations to increase access to preventive healthcare services among the largest Latino subgroup in this region (CMHI 2010).
This research study was funded by the Centers for Disease Prevention and Control as the Core Research Project of the San Diego Prevention Research Center (U48 DP00036-03) and the Ford Diversity Pre-doctoral Fellowship.