Immigrant status and increased risk of heart failure: the role of hypertension and life-style risk factors.

Abstract

Studies from Sweden have reported association between immigrant status and incidence of cardiovascular diseases. The nature of this relationship is unclear. We investigated the relationship between immigrant status and risk of heart failure (HF) hospitalization in a population-based cohort, and to what extent this is mediated by hypertension and life-style risk factors. We also explored whether immigrant status was related to case-fatality after HF.
26,559 subjects without history of myocardial infarction (MI), stroke or HF from the community-based Malmö Diet and Cancer (MDC) cohort underwent a baseline examination during 1991-1996. Incidence of HF hospitalizations was monitored during a mean follow-up of 15 years.
3,129 (11.8%) subjects were born outside Sweden. During follow-up, 764 subjects were hospitalized with HF as primary diagnosis, of whom 166 had an MI before or concurrent with the HF. After adjustment for potential confounding factors, the hazard ratios (HR) for foreign-born were 1.37 (95% CI: 1.08-1.73, p = 0.009) compared to native Swedes, for HF without previous MI. The results were similar in a secondary analysis without censoring at incident MI. There was a significant interaction (p < 0.001) between immigrant status and waist circumference (WC), and the increased HF risk was limited to immigrants with high WC. Although not significant foreign-born tended to have lower one-month and one-year mortality after HF.
Immigrant status was associated with long-term risk of HF hospitalization, independently of hypertension and several life-style risk factors. A significant interaction between WC and immigrant status on incident HF was observed.

Full text

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RESEARCH ARTICLE Open Access
Immigrant status and increased risk of heart
failure: the role of hypertension and life-style
risk factors
Yan Borné1*, Gunnar Engström1, Birgitta Essén2and Bo Hedblad1
Abstract
Background: Studies from Sweden have reported association between immigrant status and incidence of
cardiovascular diseases. The nature of this relationship is unclear. We investigated the relationship between
immigrant status and risk of heart failure (HF) hospitalization in a population-based cohort, and to what extent this
is mediated by hypertension and life-style risk factors. We also explored whether immigrant status was related to
case-fatality after HF.
Methods: 26,559 subjects without history of myocardial infarction (MI), stroke or HF from the community-based
Malmö Diet and Cancer (MDC) cohort underwent a baseline examination during 1991-1996. Incidence of HF
hospitalizations was monitored during a mean follow-up of 15 years.
Results: 3,129 (11.8%) subjects were born outside Sweden. During follow-up, 764 subjects were hospitalized with
HF as primary diagnosis, of whom 166 had an MI before or concurrent with the HF. After adjustment for potential
confounding factors, the hazard ratios (HR) for foreign-born were 1.37 (95% CI: 1.08-1.73, p = 0.009) compared to
native Swedes, for HF without previous MI. The results were similar in a secondary analysis without censoring at
incident MI. There was a significant interaction (p < 0.001) between immigrant status and waist circumference
(WC), and the increased HF risk was limited to immigrants with high WC. Although not significant foreign-born
tended to have lower one-month and one-year mortality after HF.
Conclusions: Immigrant status was associated with long-term risk of HF hospitalization, independently of
hypertension and several life-style risk factors. A significant interaction between WC and immigrant status on
incident HF was observed.
Keywords: Immigrant status, heart failure, risk factors, cohort study, case-fatality, epidemiology
Background
Heart failure (HF) is one of the leading causes for mor-
bidity and mortality, particularly in the elderly. Hyper-
tension and myocardial infarction (MI) are the main
causes of HF in the general population [1-5]. Other
important risk factors that have been associated with
incidence of HF include age, male sex, overweight, dia-
betes, smoking, physical inactivity, alcohol consumption,
inflammatory and socioeconomic factors [2,6-13].
It has repeatedly been shown that immigrants in Swe-
den have higher risk of coronary heart disease and
stroke compared to Swedish-born subjects [14-17]. In a
previous study of the entire population of Malmö, Swe-
den, we found substantial differences in risk of HF hos-
pitalization among foreign-born subjects [18]. In that
study, increased incidence of HF hospitalizations was
found in immigrants from Finland, Former Yugoslavia
and Hungary. However, it is still unclear to what extent
the increased risk in these groups could be explained by
major biological and lifestyle risk factors for HF, e.g.,
hypertension, overweight, and smoking.
Thus, the purpose of the present study was to further
explore the association of immigration status and risk of
* Correspondence: Yan.Borne@med.lu.se
1Department of Clinical Sciences, Cardiovascular Epidemiology, Skåne
University Hospital, Lund University, 20502 Malmö, Sweden
Full list of author information is available at the end of the article
Borné et al. BMC Cardiovascular Disorders 2012, 12:20
http://www.biomedcentral.com/1471-2261/12/20
© 2012 Borné et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons
Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited.

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HF hospitalization in an urban population-based cohort
and to what extent the relationship is explained by con-
ventional cardiovascular risk factors. We also explored
whether immigrant status was related to case-fatality
(e.g. 1-month and 1-year, respectively) after HF.
Methods
Study population
The Malmö Diet and Cancer (MDC) cohort is a pro-
spective cohort study from the city of Malmö in south-
ern Sweden. Sample characteristics, data collection and
clinical definitions for MDC have been described pre-
viously [19-21]. Briefly, 28,449 men (n = 11,246, born
1923-1945) and women (n = 17,203, born 1923-1950)
attended a baseline examination between March 1991
and September 1996. Participants underwent sampling
of peripheral venous blood, measurement of blood pres-
sure and anthropometric measures and filled out a self-
administered questionnaire.
Subjects with history of cardiovascular events (coronary
events or stroke, n = 970 subjects) or HF (n = 46 subjects)
at the baseline examination were excluded. In addition, sub-
jects were also excluded due to missing information on
blood pressure (BP), waist circumference (WC), smoking
habits, alcohol consumption, physical activity, leukocyte
counts, educational level, marital status and country of
birth. Thus, the final study population in the analysis con-
sisted of 26,559 (10,227, 38.5% men and 16,332, 61.5%
women) subjects, aged 45-73 years. The study was approved
by the ethical committee at Lund University Lund, Sweden,
and all participants provided informed consent.
Measurements and definitions
Information on current use of BP lowering, lipid-lower-
ing or anti-diabetic medications, smoking habits, alcohol
consumption, leisure time physical activity, educational
level, marital status and country of birth were obtained
from a self-administered questionnaire [20]. WC (in cm)
was measured midway between the lowest rib margin
and iliac crest in the standing position without clothing.
WC was stratified into normal WC and high WC (≥ 94
cm for men and ≥ 80 cm for women) [22]. Blood pres-
sure was measured using a mercury-column sphygmo-
manometer after 10 minutes of rest in the supine
position. Hypertension was defined as blood pressure
equal or above 140/90 mm Hg or current use of blood
pressure-lowering medication. Leukocyte concentrations
were analysed consecutively in fresh heparinized blood.
Diabetes mellitus was defined as fasting whole blood
glucose level greater than 109 mg/dL (e.g. 6.0 mmol/L),
self-reported physician’s diagnosis of diabetes, or use of
antidiabetic medications. Subjects were categorized into
current smokers (i.e., those who smoked regularly or
occasionally) or non-smokers (i.e., former smokers and
never smokers). High alcohol consumption was defined
as > 40 gram alcohol per day for men and > 30 g/day
for women. Leisure time physical activity was grouped
as lowest quartile or other. As previously described edu-
cational level was defined as low education (up to grade
9) and high (> 9 years) [23]. Marital status was categor-
ized into married or unmarried. Immigrant status was
grouped as Swedish-born and foreign- born. We were
unable to study immigrants from individual countries of
birth due to limited numbers of HF cases.
Ascertainment of cardiovascular events and HF
The Swedish Hospital Discharge Register (SHDR) was
used for case retrieval. Validation study has shown that
a primary diagnosis of HF in the SHDR has a validity of
95% [24]. The corresponding figure for MI is 94% [25].
HF was defined as International Classification of Dis-
eases- 8threvision (ICD-8) code 427.00, 427.10 and
428.99; 428 (ICD-9); and I50, I11 (ICD-10) as the pri-
mary diagnosis [24]. Non-fatal MI was defined as 410
(ICD-8 and 9) or I21 (ICD-10) [25]. Information on
mortality was obtained through the Swedish Cause of
Death Register. All subjects were followed from the
baseline examination until a first diagnosis of HF, emi-
gration from Sweden, death or December 31st, 2008,
whichever came first.
Statistical analysis
Cox proportional hazards regression was used to exam-
ine the association between selected immigrant status
and risk of HF hospitalization in the MDC cohort.
Hazard ratios (HR), with 95% confidence interval (CI)
were calculated. Age and sex were included as covariates
in the basic model. Secondly, we also adjusted for systo-
lic BP, use of BP-lowering medication, lipid-lowering
medication, diabetes mellitus, WC, current smoking,
high alcohol consumption, low physical activity and leu-
kocyte counts. Possible interactions between immigrant
status and age, sex and cardiovascular risk factors on
incidence of HF were explored by introducing interac-
tion terms in the multivariate model. The primary ana-
lysis was performed with censoring at first nonfatal MI
during follow-up, i.e., cases with MI prior to HF were
not counted. Secondary analysis included all HF incident
cases, regardless of MI. Two-sided p values < 0.05 were
considered significant. The Kaplan-Meier curve was
used to illustrate incidence of hospitalization due to HF
in relation to immigrant status and waist circumference.
Case-fatality rates were calculated as the proportion of
those with a HF hospitalization that died within 1-
month and 1-year, respectively. Cox proportional
hazards regression was used and adjusted for age, sex
and year of HF event. All analyses were performed using
PASW version 18 (SPSS Inc., Chicago, Illinois).
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Results
Overall, mean age (± standard deviation) at baseline was
58 ± 7.6 years and 61.5% were women. A total of 23,430
subjects were born in Sweden and 3,129 (11.8%) were
born outside Sweden. Of those born outside Sweden,
the majority came from Denmark (10.5%), Former
Yugoslavia (8.3%), Finland (7.6%), Germany (8.8%),
Poland (5.0%) and Hungary (4.3%). Baseline characteris-
tics of Swedish- born and foreign- born in relation to
conventional cardiovascular risk factors (WC, leukocyte
count, systolic BP, use of BP-lowering and lipid-lowering
medication, diabetes mellitus, current smoking, high
alcohol consumption, low physical activity) and socioe-
conomic factors (educational level, marital status) are
presented in Table 1. Foreign-born subjects were
younger, more often current smokers, diabetics, high
alcohol consumers, and had more often low physical
activity than those born in Sweden. During a mean fol-
low-up of 15 years, a total of 764 individuals (325 men
and 273 women) were hospitalized with HF as primary
diagnosis. Of them, 166 (96 men and 70 women) had an
incident MI before or concurrent with HF hospitaliza-
tion during follow-up. The latter group was censored at
the time of the infarction in the primary analysis.
Risk of HF hospitalizations in relation to immigrant status
The overall analysis showed higher risk of HF hospitali-
zation for foreign-born compared to Swedish- born.
Adjusted for age and sex, foreign- born had a signifi-
cantly higher risk for HF (HR: 1.44; 95% CI, 1.14-1.82)
compared to Swedish-born. This increased risk
remained (HR: 1.37; 1.08-1.73) after adjustment for
other possible confounders, Table 2. If cases with MI
before or concurrent with HF hospitalization (n = 166)
were included in the analysis, the risk for HF hospitali-
zation among foreign-born (HR: 1.24; 1.01-1.54) was
only marginally changed, Table 2.
In the final model, age and male sex, increased WC,
leukocyte count, systolic BP, use of BP-lowering medica-
tion, diabetes, smoking, high alcohol consumption, low
physical activity, low educational level were indepen-
dently associated with an increased risk for HF, Table 2.
Interaction between immigrant status and other risk
factors on incidence of HF
Interaction terms between covariates were added in the
final Cox’s proportional hazards model with adjustment
for possible confounders. There was a statistically signif-
icant interaction between immigrant status and WC (p
< 0.001) on incidence of HF. There were no other sig-
nificant interactions between immigrant status and risk
factors.
To further explore the interaction between country of
birth and WC, WC was stratified into normal and high
WC in men and women, respectively [22], Table 3 and
Figure 1. After stratification for WC, a significant higher
risk of HF was only observed in foreign-born with high
WC (HR: 2.11; 95% CI, 1.62-2.76), while foreign-born
with normal WC had similar risk (HR: 1.17; 0.85-1.60)
as compared to Swedish natives with normal WC.
Table 1 Characteristics of subjects in the Malmö diet and cancer (MDC) cohort in relation to immigration status, at the
baseline examination 1991-1996
MDC (N = 26,559)Swedish-born
(n = 23,430)
Foreign-born
(n = 3,129)
P value
Mean age (years)58.2 ± 7.656.9 ± 7.2< 0.001
Men (%) 38.439.1< 0.001
Waist circumference (cm) 84 ± 15 85 ± 10< 0.001
SBP (mmHg) 141 ± 20140 ± 20 < 0.001
DBP (mmHg)
Leukocytes (109/L)
86 ± 10 85 ± 130.426
6.4 ± 2.2 6.5 ± 3.50.183
Hypertension (%) 40.538.6 < 0.001
Use of BP-lowering medications (%)*41.140.1< 0.001
Use of lipid-lower medications (%)2.42.10.279
Diabetes (%) 2.8 3.3< 0.001
Current smoker (%)27.9 31.0 < 0.001
High alcohol consumption (%)4.2 5.20.015
Low physical activity (%)24.5 28.4< 0.001
Low educational level (%) 42.135.3< 0.001
Married (%)65.7 62.3 < 0.001
All other values are mean ± SD, unless otherwise stated. * Use of blood pressure (BP)-lowering medications is calculated as proportions of hypertensives in each
group (n = 9488 and n = 1207, respectively).
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Case fatality
Thirty-two (4.2%) subjects died within 1-month after the
HF hospitalization and 95 (18.9%) had died one year
after the HF. After adjustment for age, sex and year of
the HF hospitalization, the immigrants group tended to
have lower one-month and one-year mortality (HR:
0.20; 95% CI: 0.03-1.44, p = 0.109 and HR: 0.47; 0.22-
1.01, p = 0.053, respectively).
Discussion
The present population-based cohort study shows that
being foreign-born is associated with significantly higher
risk for HF hospitalization, independent of several biolo-
gical, lifestyle and socioeconomic risk factors. The
results are in line with prior studies on immigration sta-
tus and cardiovascular disease (CVD) in Sweden
[14,16,18]. However, the present results also show that
the increased risk among immigrants is modified by the
presence of other risk factors. There was a significant
interaction between WC and immigrant status on risk
of HF hospitalizations, and the increased incidence was
mainly observed in those with high WC.
One possible explanation for the increased risk of HF
hospitalization in foreign-born compared to Swedish-
born might be influences from their country of birth.
Compared to 15.6% being foreign-born in whole Malmö
[18], the proportion of foreign-born in the MDC cohort
were 11.8% of all study subjects. This group mainly
came from Denmark, Former Yugoslavia, Finland, Ger-
many, Poland and Hungary. The majority of these coun-
tries have higher incidence of CVD compared to
Sweden [26,27]. Since most cases of HF are caused by
hypertension or CHD, the high CVD risk in their coun-
try of origin might partly explain the increased risk of
hospitalization due to HF. It has often been suggested
that socioeconomic differences could explain the high
morbidity in immigrant groups. Studies have shown that
residential areas in Malmö with high proportion of
immigrants and low socioeconomic status have high
incidence of CVD [28,29]. However, the immigrants in
this cohort study had higher education levels than those
born in Sweden and the present results remained signifi-
cant also after adjustments for education and marital
status. Socioeconomic differences therefore seem to be
Table 2 Final multivariate model for first hospitalization due to heart failure in the MDC cohort
INCIDENT HF WITHOUT PRIOR MI
HR† (95% Cl)
p value ALL INCIDENT HF
HR† (95% Cl)
p value
Foreign-born (yes vs no)
1.37 (1.08-1.73) 0.009 1.24 (1.01-1.54) 0.045
Age (per 1 year)
1.11 (1.09-1.12) < 0.0011.11 (1.09-1.12) < 0.001
Male sex (yes vs no)
1.71 (1.44-2.03)< 0.001 1.68 (1.45-1.95)< 0.001
Waist circumference (per 5 cm)
1.03 (1.02-1.04) < 0.0011.03 (1.02-1.04) < 0.001
Systolic blood pressure (per 10 mm Hg)
Leukocyte count (per 109/L)
1.13 (1.09-1.18) < 0.001 1.15 (1.11-1.20) < 0.001
1.02 (1.01-1.03)0.005 1.02 (1.01-1.03)0.001
Use of BP-lowering medications (yes vs no)
2.02 (1.69-2.41) < 0.0012.03 (1.74-2.37) < 0.001
Use of lipid-lowering medications (yes vs no)
1.10 (0.73-1.63)0.6581.43 (1.06-1.94)0.021
Diabetes mellitus (yes vs no)
2.78 (2.12-3.65) < 0.0012.80 (2.22-3.54)< 0.001
Smoking (yes vs no)
1.94 (1.63-2.32)< 0.0012.11 (1.81-2.46) < 0.001
High alcohol consumption (yes vs no)
1.53 (1.10-2.14)0.0121.40 (1.03-1.91)0.032
Low physical activity (yes vs no)
1.27 (1.07-1.52) 0.0081.26 (1.07-1.47) 0.004
Unmarried (yes vs no)
1.21 (1.02-1.44)0.0281.15 (0.98-1.34)0.081
Low educational level (yes vs no)
1.18 (1.00-1.39)0.0501.23 (1.06-1.42)0.005
Hazard ratio (HR)† in the final model. Cl, confidence interval.
Table 3 Interaction between immigration status and waist circumference (WC) on incidence of HF in the MDC cohort
INCIDENT HF WITHOUT PRIOR MI
HR† (95% Cl)
ALL INCIDENT HF
HR† (95% Cl)
Interaction term Immigrant status*WC
P < 0.001
P < 0.001
Swedish-born with normal WC (reference)11
Swedish- born with high WC1.67 (1.38-2.02)1.71 (1.45-2.03)
Foreign- born with normal WC1.17 (0.85-1.60)1.06 (0.79-1.42)
Foreign- born with high WC 2.62 (1.87-3.67)2.45 (1.80-3.34)
Hazard ratio HR† adjusted for age, sex, civil status, education level, smoking habits, alcohol consumption, physical activities, BP-lowering medication, lipid-
lowering medication, systolic BP, leukocyte count and diabetes mellitus. Cl, confidence interval.
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an insufficient explanation for the increased incidence of
HF hospitalizations in foreign-born.
In the present study, a wide range of biological and
life-style risk factors were independently associated with
risk for HF. The increased HF risk for foreign-born still
remained after adjustment for these risk factors. There
was a significant interaction between immigrant status
and WC on incidence of HF, which showed that the
highest risk for HF was limited to foreign-born with
high WC. As a heterogeneous group there are substan-
tial differences among immigrants to Sweden by country
of origin [30,31]. A previous cross-sectional study, based
on the MDC cohort, found that women born in Hun-
gary, Poland and Germany had higher WHR compared
to Swedish-born women, after taking age, height, smok-
ing, physical activity, occupation and percentage of body
fat into account [31]. In men, WHR was increased in
participants from Yugoslavia, Germany and Finland [31].
In that study length of residence in Sweden was found
inversely associated with central adiposity in immigrants
and it was concluded that immigrants may be at higher
risk of obesity-related comorbidities [31].
Several studies have shown that increased abdominal
adiposity is strongly associated with cardiovascular risks
[10,32,33]. Inadequate exercise, over-intake of food or
alcohol, metabolic imbalance and genetic abnormalities
could cause high WC. The high WC influence known
risk factors, e.g., dyslipidemia, hypertension, glucose
intolerance, inflammation markers [13,34,35], that
increase risk of developing HF.
Foreign-born tended to have lower mortality after HF
compared to Swedish- born, but the difference did not
reach statistical significance. This might be explained by
the so-called “obesity paradox”, since the foreign-born
had higher WC than Swedish-born and overweight and
high WC paradoxically have been associated with
improved outcome among HF patients [36,37]. It has
been reported that immigrants and native Swedish HF
patients are quite similar in terms of symptoms, health
care seeking, the distress level, physical function, emo-
tional state and self care [38,39]. More immigrants than
Swedes are referred to HF clinic after discharge for fol-
low-ups [40], which could reduce mortality in this
group.
Strength and limitation
The study used large numbers of subjects with a long
follow-up period and identified large numbers of HF
events [19,21]. The cardiovascular endpoints were
retrieved from national registers, and studies have
showed high case validity for HF and MI in the register
data [24,25].
A main limitation of the present study is lack of infor-
mation on type and cause of HF. Previous studies have
demonstrated that immigrants to Sweden have an
increased incidence of CVD [16,17]. However, we can
only speculate whether the increased risk of hospitaliza-
tions due to HF among immigrants in the present study
was related to a reduced or normal ejection fraction. In
addition, we were unable to include HF patients who
only were treated as out-patients. The total incidence of
HF is therefore underestimated and we cannot make
any conclusion about less severe cases which often are
treated as out-patients. The 40.8% participation rate in
the MDC study questions the representativity of the
population [41]. It was shown that non-participants had
higher mortality rate than participants in the MDC
cohort. However, there was no substantial difference
when comparing baseline characteristics of subjects in
the MDC study to a survey study from the Malmö city
with participation rate of 75% [41]. Another short-com-
ing is that we were unable to study immigrants by coun-
try of origin due to limited number of HF events,
however in a previous study based on the whole Malmö
city population we found an increased incidence of HF
hospitalizations in immigrants from Finland, Former
Yugoslavia and Hungary [18].
The MDC study required participants to be able to
speak Swedish language. One question is whether this
group of immigrants is representative to all immigrants
in the city. Among all subjects aged 45-73 years in the
whole Malmö population, foreign- born had a signifi-
cantly higher risk for HF (HR: 1.27; 95% CL, 1.17-1.38)
compared to Swedish-born after adjustment for age and
sex. The corresponding HR in the MDC cohort was
1.44 (95% CI; 1.14-1.82), and we therefore believe that
the results can be generalized.
The choice of risk factors variables in the multivariate
model can influence the results since adjustments for
risk factors that are mediators in the causal pathway will
Figure 1 Heart failure hospitalization free survival in relation
to immigration status and high/normal waist circumference.
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underestimate of the relation, while leaving out genuine
confounders will overestimate the result. The variables
used for adjustments in the study, e.g., age, sex, smok-
ing, hypertension, diabetes, abdominal obesity, alcohol
consumption and physical activity are well known cardi-
ovascular risk factors [2,4,5,9,10,12,42,43]. Educational
level is a widely used measure of socioeconomic circum-
stances in epidemiologic studies, and is considered to be
related to health outcome by its influence on lifestyle
behaviors and value [44]. Low educational level has
been reported to associate with higher cardiovascular
risk [45,46]. Marital status has been found associated
with HF [7,47].
The lack of follow-up data regarding anthropometric
measures and other risk factors in the present study is
another issue to be discussed. It is possible that biologi-
cal factors, e.g., blood pressure and WC changed during
the follow-up. However, this is usually a slow process
and one study found that adipose tissue distribution is
stable through the lifespan [48]. Some subjects might
change the status in terms of smoking, physical activity,
alcohol consumption and marriage. It is unknown
whether change of risk factors during the follow-up
could be differential between immigrants and native
Swedes.
Conclusions
In conclusion, immigrant status is associated with long-
term risk of HF hospitalization, independently of hyper-
tension and several life-style risk factors. A significant
interaction between WC and immigrant status on inci-
dent HF was observed.
Acknowledgements
This work and the Malmö Diet and Cancer study was supported by grants
from the Swedish Cancer Society, the Swedish Research Council (Dnr 2011-
3891), the Swedish Heart and Lung Foundation, the faculty of medicine,
Uppsala University and Lund University, the Malmö city Council and by
funds from the Region Skåne, Skåne University Hospital, Malmö and
Lundströms Foundation.
Author details
1Department of Clinical Sciences, Cardiovascular Epidemiology, Skåne
University Hospital, Lund University, 20502 Malmö, Sweden.2Department of
Women’s and Children’s Health, International Maternal and Child Health
(IMCH), Uppsala University, 751 85 Uppsala, Sweden.
Authors’ contributions
YB, GE and BH constructed the concept and design of the project; YB
performed the analysis and drafted the manuscript; YB, GE, BE and BH
participated in the analysis and interpretation of data and revised the
manuscript critically. All authors approved the final manuscript to be
published.
Competing interests
Gunnar Engström is employed as senior epidemiologist by AstraZeneca R&D.
Received: 7 December 2011 Accepted: 26 March 2012
Published: 26 March 2012
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Pre-publication history
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Cite this article as: Borné et al.: Immigrant status and increased risk of
heart failure: the role of hypertension and life-style risk factors. BMC
Cardiovascular Disorders 2012 12:20.
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