Provision of professional interpreters and Heart School attendance for foreign-born compared with native-born myocardial infarction patients in Sweden

Graphical abstract


Introduction
Cardiovascular (CV) disease is a major cause of death worldwide and myocardial infarction (MI) is the most frequent acute CV disease [1,2].MI outcomes have improved during the last decades due to improvements in acute management, favorable lifestyle changes, and more effective primary and secondary preventive therapies [3,4].A majority of MI cases are attributed to modifiable risk factors which are largely preventable [3].Yet, the risk of recurrence remains high, and optimization of CV risk factors and lifestyle changes post-MI are of uttermost importance [5,6].Secondary prevention by cardiac rehabilitation (CR), including professional support to modify unfavorable lifestyles, improve drug adherence, provide patient education, and increase patient empowerment, has been shown to reduce the risk of recurrent CV events and death [4,7].Accordingly, international guidelines have repeatedly advocated the use of CR post-MI [8,9].In Sweden, Heart School (HS) is a core CR element providing interactive education on diet, exercise, smoking cessation, and health promotion in a group setting.Previous studies showed that attending HS was associated with a lower risk of recurrent CV events and favorable long-term prognosis [7,10,11].
Many developed countries have undergone demographic changes because of immigration and the influx of refugees [12,13].In Sweden, the proportion of foreign-born residents increased from 11.7 % in 2000 to 19.7 % in 2020 [14].Consequently, language has become an increasingly important potential healthcare barrier, especially in a context such as CR, in which verbal and written communication is the main tool for education to achieve necessary lifestyle changes, improve drug adherence, and increase patient empowerment.Previous studies from the United States and Canada have shown that patients with limited English proficiency (LEP) had fewer physician visits and were less likely to receive preventive services [15][16][17].In Denmark, CR core components were provided to a lesser degree to non-Danish-speaking patients without improvement over time [18,19].The use of professional interpreters has been suggested to bridge language barriers and improve outcomes in a wide range of patient populations [17,[20][21][22][23].To our knowledge, the use of professional interpreters has not been studied in MI patients and no previous study has assessed the association between the provision of professional interpreters and attendance to important CR elements in post-MI patients with limited majority language proficiency (the language predominantly spoken by healthcare professionals in the healthcare system that the patients attend).
The primary aim was to investigate HS attendance in foreign-born and native-born MI patients and the association between the provision of professional interpreters and HS attendance at CR follow-up visits.
A secondary aim was to evaluate treatment goal attainment based on HS attendance.

Methods
This was a sub-study to the Perfect Cardiac Rehabilitation (Perfect CR) study which has been previously described [24].Briefly, the Perfect CR study was observational, and it collected and merged organizational and patient-specific data into one database.Organizational variables were collected by a detailed questionnaire sent to all 78 CR centers in Sweden.These centers were actively reporting patient-level data to the Swedish Web-system for Enhancement and Development of Evidencebased care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART).The purpose of Perfect CR was to assess key elements of guidelines-recommended CR, including both structure and processes applied in the CR programs and their outcomes [24][25][26].The survey also gathered information on the routine provision of professional interpreters to non-Swedish-speaking patients during CR followup after MI.A professional interpreter is defined as someone who specializes in interpreting from one spoken language to another and facilitating communication between a foreign-born patient with low Swedish language proficiency and healthcare professionals.In Sweden, the information about patients' native language and the need for interpreters is registered in patient records.CR follow-up visits and professional interpreters are booked in advance.In this study, if professional interpreters were not provided by the CR centers, ad hoc interpreters such as family members and friends were allowed to interpret in certain centers.Ad hoc interpreters (family members and friends) were not the subject of this analysis.In this study, CR centers were defined as centers providing professional interpreters or not.
The study population consisted of all MI patients hospitalized in Sweden during the predefined study period reflected by the questionnaire (1st Nov. 2015 until 31st Oct. 2016) with a one-year follow-up.The inclusion criteria were: 1) type 1 MI diagnosis, 2) age between and 74 years, and 3) attending at least one of the two CR visits during the first year post-MI at which data is registered in SWEDEHEART.Patientspecific variables were retrieved from the SWEDEHEART registry and included baseline characteristics, in-hospital management, and followup including risk factor management, (Table 1, Table S1 and S2).The registry is regularly monitored by external monitors, with more than % agreement between registered information and medical records [27].Furthermore, census-based individual-level data including information about death, country of birth, marital status, employment, education level, and disposable income were retrieved from Statistics Sweden, which is the government agency responsible for providing official statistics [28].

Exposure and outcome definitions
In the primary analysis, HS attendance in foreign-born patients was compared with native-born (born in Sweden) patients.Secondly, the association between HS attendance (outcome) and the provision of professional interpreters at follow-up visits (exposure) was assessed.Finally, attainment of secondary prevention goals and HS attendance in foreign-born and native-born patients (exposure) was investigated: 1) LDL-cholesterol < 1.8 mmol (treatment goal during the study period), 2) systolic blood pressure < 140 mmHg, 3) attending physical trainingbased CR (supervised physical training at the hospital during the follow-up phase), and 4) smoking cessation.To achieve abstinence from smoking, current smokers were offered smoking cessation counseling by specially trained counselors.

Statistics
Continuous variables are presented as means with standard deviations (SD) and categorical variables as counts with percentages.Baseline and peri-procedural characteristics were compared based on whether the patient was native-born or not.The Kolmogorov-Smirnovś normality test was used to test whether data were normally distributed or not.The chi-square test was used for categorical variables and Student's T-test or Mann-Whitney U test (depending on if the variable had a normal distribution or not) for continuous variables.For HS attendance, logistic regression models presenting crude and adjusted odds ratios (OR) with 95 % confidence intervals (CI) were developed.Adjustments in the first model included age and sex; the second model added comorbidities, medications, and management variables (hypertension, smoking status, diabetes mellitus, previous MI (before index), previous revascularization, type of MI (ST-elevation MI [STEMI]/non-STEMI,) and discharge medications (aspirin, P2Y12-inhibitors, beta-blockers, angiotensin-converting enzyme [ACE] inhibitors, angiotensin receptor blockers [ARB], statins, and diabetes medications)).Finally, in the third model socioeconomic variables were added (disposable income, education level, and marital status).
For patient-related comparisons, native-born patients were the reference group, and for system-related comparisons, CR sites not offering professional interpreters were the reference group.
We performed two interaction tests: 1) country of birth (native-born or foreign-born) and the provision of professional interpreters on HS attendance.2) country of birth (native-born or foreign-born) and HS attendance on secondary prevention goals.
A p-value < 0.05 was considered statistically significant.All analyses were performed using the SPSS 29.0 statistical software package (SPSS Inc., Chicago, Illinois, USA).

Ethical approval and consent to participate
This study was carried out in accordance with the Declaration of Helsinki and it was approved by the Ethics Committee at Lund University (ethical permit number 2018-55).
Under Swedish legislation, patients included in the SWEDEHEART registry were informed, before inclusion, about their participation in the registry and the right to opt-out.
Stratified analysis based on HS attendance showed minor differences in baseline characteristics in foreign-born patients.In contrast, nativeborn patients attending HS were less likely to be smokers, to have hypertension, diabetes mellitus, or previous revascularization, and they were more likely to be married/cohabiting, and to have higher education and disposable income (Table S2).
Attending HS was associated with better attainment of all four secondary prevention goals in foreign-born as well as native-born patients.In foreign-born patients, HS attendance was associated with a higher proportion of patients achieving target levels of LDL cholesterol < 1.8 mmol/L (70.4 vs 64.3 %, p = 0.02), systolic blood pressure < 140 mmHg (91.0 vs 84.2 %, p < 0.001), attending physical training-based CR (71.2 vs 35.7 % p < 0.001), and smoking cessation after MI (68.3 vs 59.3 %, p < 0.001).In native-born patients, HS attendance was associated with    4).HS attenders had a higher participation rate in smoking cessation counselling compared with non-attenders, (32.9 vs 15.0 %, p < 0.001) in foreign-born and (23.1 vs 14.3 %, p < 0.001) in native-born patients (Table S3).

Discussion
This nationwide study assessing attendance to a fundamental part of CR in post-MI patients had three major findings.First, a significantly     lower proportion of foreign-born patients attended HS, compared with native-born.Second, routinely providing professional interpreters at the CR centers was associated with improved HS attendance among foreignborn, with no difference in native-born patients.The difference in effect of professional interpreters among foreign-born and native-born MI patients was supported by a significant interaction test.Third, attending HS was equally associated with better attainment of secondary prevention goals in foreign-born and native-born patients.Foreign-born patients were more likely to present at younger age, were more often male and had a more severe CV risk profile, with a higher prevalence of smoking, diabetes mellitus, previous MI and revascularization compared with native-born patients.These findings are congruent with previous studies, which have shown a different and more severe CV risk profile in foreign-born patients [29,30].
HS attendance was significantly lower among foreign-born compared with native-born patients.In English-speaking countries, previous studies have demonstrated that preventive services such as vaccination, disease screening, Pap tests, mammograms, and physician visits are underutilized among patients with LEP, which is in line with our results [15][16][17].The underutilization of preventive services among LEP patients has been attributed to socioeconomic factors, cultural aspects, and language barriers.In a Canadian study assessing the use of preventive services in English-proficient and LEP patients, the association between language and preventive services persisted despite adjustment for socioeconomic factors and cultural aspects, reflecting the importance of language barriers in contact with health care [15,16].This is congruent with our results, showing very little impact of adjustment for socioeconomic factors on the likelihood of HS attendance for foreign-born patients.In studies from Denmark, the role of language barriers has been suggested as the main reason for the incomplete provision of core components of CR to non-Danish-speaking MI patients.Furthermore, a lower uptake and a higher discontinuation of nonpharmacological prevention programs after MI (including physical training, dietary advice, and patient education) were reported in foreign-born compared with native-born patients, further supporting our results [18,19].Given the previously reported positive effects on outcome associated with CR, efforts should be made to increase HS attendance in all patients with a history of MI, especially those with several risk factors.In the present study, routinely providing professional interpreters at the CR centers was associated with higher attendance in HS among foreign-born but not among native-born patients.These results indicate that the provision of professional interpreters bridges the language barrier between the healthcare professionals and foreign-born patients and improves HS attendance.It could be suggested that CR centers routinely providing professional interpreters may have more resources and better performance in general.However, the lack of association between centers providing professional interpreter and HS attendance in native-born patients further strengthens the interpretation that the provision of professional interpreters is not just a proxy for a well-functioning site but impacts HS attendance per se in foreign-born patients.Importantly, adjustment of potential confounders such as age, sex, comorbidities, medications, management, and socioeconomic variables did not change the association.Our findings indicate that the provision of professional interpreters may in fact help to overcome language barriers and improve CR attendance Attending HS or a similar form of theoretically administered patient education after an MI has been associated with better attainment of secondary prevention goals and reduced CV event rates including allcause mortality [7,10,11].In a randomized trial, a relatively short structured educational programmes after MI was associated with lower risk of CV events [11].A meta-analysis investigating the length of patient education on attainment of secondary prevention goals, found that patient education was associated with better attainment of secondary prevention goals, irrespective of length of patient education [11].In accordance with previous findings, in our study, HS attendance was associated with better attainment of all four secondary prevention goals with no significant interaction between country of birth (native-born or foreign-born) and HS attendance on achievement of treatment goals.
To the best of our knowledge, the association between provision of professional interpreters and attendance to core components of CR (associated with attainment of secondary prevention goals) post-MI has not been studied previously.It is reasonable to believe that our findings are applicable to other areas of health care and that use of professional interpreters should be encouraged to improve care for patients with low proficiency in the majority language.Supporting this, in a wide range of patient populations, the provision of professional interpreters improved outcomes by reducing unnecessary interventions in obstetric patients, lowering the rate of readmissions, and reducing the length of hospital stay in internal medicine patients [17,[20][21][22].Analogous to MI patients, in a previous study on LEP patients with diabetes and poor glycemic control, switching to a language-concordant physician to bridge the language barriers showed significant improvement both in glycemic control and LDL-cholesterol levels.[23].Taken together, these studies further emphasize the role of language barriers in healthcare and support our findings suggesting improved care in foreign-born patients with routine provision of professional interpreters.

Strengths and limitations
The main strength of our study was the nationwide inclusion of all 78 active CR centers in Sweden with a 100 % response rate addressing the use of professional interpreters, combined with high-quality data from multiple registries for individual patients treated at these centers during the corresponding period.There are some important limitations to be mentioned.First, this was an observational study with inherent limitations including the possibility of unmeasured confounding.However, multivariable adjustment did not significantly change the observed associations.Second, in foreign-born patients, data on proficiency in the Swedish language was not available on the individual level.Also, the provision of professional interpreters was reported at the CR center level, not for individual patients.However, given the association observed for the whole foreign-born population, irrespective of individual needs, it is likely that the association would be even stronger for Results are presented as numbers (percentages).Abbreviations: CR, cardiac rehab; MI, myocardial infarction.
patients with the lowest proficiency in the Swedish language.

Conclusion
Foreign-born MI patients attended HS less often than native-born patients.Still, the provision of professional interpreters at follow-up visits at CR centers was associated with improved HS attendance among foreign-born patients.The association between HS attendance and attainment of secondary prevention goals was similar in the two groups.Therefore, the provision of professional interpreters appears to improve CR among foreign-born patients. Declarations.

Fig. 1 .
Fig. 1.Heart school attendance after a myocardial infarction based on country of birth and sites offering professional interpreters or not.Abbreviations: FB, foreignborn; PI, professional interpreter; NB, native-born.
as odds ratios (OR) and 95 % confidence interval (CI).Sites not offering professional interpreters are the reference group.Model 1 includes age and sex as covariables.Model 2 includes model 1 and comorbidities, medications, and management variables.Model 3 includes model 2 and socioeconomic variables.

Fig. 2A .
Fig. 2A.Odds ratios for participation in heart school for foreign-born patients at sites offering professional interpreters vs sites not offering professional interpreters.Model 1 includes age and sex as covariables.Model 2 includes model 1 and comorbidities, medications, and management variables.Model 3 includes model 2 and socioeconomic variables.

Fig. 2B .
Fig. 2B.Odds ratios for participation in heart school for native-born patients at sites offering professional interpreters vs sites not offering professional interpreters.Sites not offering professional interpreters are the reference group.Model 1 includes age and sex as covariables.Model 2 includes model 1 and comorbidities, medications, and management variables.Model 3 includes model 2 and socioeconomic variables.

Table 2
Heart School attendance in foreign-born patients.

Table 3
Heart School attendance and provision of professional interpreters.

Table 4
Attainment of secondary prevention goals in patients attending Heart School compared with patients not attending Heart School.