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Mitochondrial DNA haplogroup T is associated with coronary artery disease and diabetic retinopathy: a case control study
- Barbara Kofler1Email author,
- Edith E Mueller1,
- Waltraud Eder1,
- Olaf Stanger2,
- Richard Maier3,
- Martin Weger3,
- Anton Haas3,
- Robert Winker4,
- Otto Schmut3,
- Bernhard Paulweber5,
- Bernhard Iglseder6,
- Wilfried Renner7,
- Martina Wiesbauer1,
- Irene Aigner2,
- Danijela Santic1,
- Franz A Zimmermann1,
- Johannes A Mayr1 and
- Wolfgang Sperl1
© Kofler et al; licensee BioMed Central Ltd. 2009
Received: 01 October 2008
Accepted: 21 April 2009
Published: 21 April 2009
There is strong and consistent evidence that oxidative stress is crucially involved in the development of atherosclerotic vascular disease. Overproduction of reactive oxygen species (ROS) in mitochondria is an unifying mechanism that underlies micro- and macrovascular atherosclerotic disease. Given the central role of mitochondria in energy and ROS production, mitochondrial DNA (mtDNA) is an obvious candidate for genetic susceptibility studies on atherosclerotic processes. We therefore examined the association between mtDNA haplogroups and coronary artery disease (CAD) as well as diabetic retinopathy.
This study of Middle European Caucasians included patients with angiographically documented CAD (n = 487), subjects with type 2 diabetes mellitus with (n = 149) or without (n = 78) diabetic retinopathy and control subjects without clinical manifestations of atherosclerotic disease (n = 1527). MtDNA haplotyping was performed using multiplex PCR and subsequent multiplex primer extension analysis for determination of the major European haplogroups. Haplogroup frequencies of patients were compared to those of control subjects without clinical manifestations of atherosclerotic disease.
Haplogroup T was significantly more prevalent among patients with CAD than among control subjects (14.8% vs 8.3%; p = 0.002). In patients with type 2 diabetes, the presence of diabetic retinopathy was also significantly associated with a higher prevalence of haplogroup T (12.1% vs 5.1%; p = 0.046).
Our data indicate that the mtDNA haplogroup T is associated with CAD and diabetic retinopathy in Middle European Caucasian populations.
Mitochondria are the primary source of endogenous reactive oxygen species (ROS), generated through oxidative phosphorylation (OXPHOS) as a by-product of ATP synthesis. It is a generally accepted principle that in normal cells, ROS form a regular part of diverse redox signalling pathways, whereas in many types of chronic and cardiovascular diseases, ROS production exceeds antioxidant capacity with damaging effects on cell function and structure . Therefore, mitochondrial dysfunction has been implicated in the pathogenesis of several diseases characterised by free radical-induced damage. Given the central role of mitochondria in energy and ROS production, mitochondrial DNA (mtDNA) is an obvious candidate for genetic susceptibility studies on atherosclerotic processes. The extranuclear mitochondrial genome is highly polymorphic and this variation could contribute to the range of complex traits in energy metabolism. Four of the enzymatic complexes that constitute the oxidative phosphorylation system (OXPHOS) are partially encoded by the mtDNA. Rare pathogenic mutations of the mtDNA, that either impair mitochondrial protein synthesis or impair proteins encoded by the mtDNA have been associated with more than 70 human diseases .
During evolution, a number of mutations have accumulated in the mtDNA . Mutations acquired during evolution have subdivided the human population into a number of discrete, region specific, mitochondrial clades or haplogroups. MtDNA haplogroups are defined on the basis of specific single nucleotide polymorphisms (SNPs) scattered throughout the mitochondrial genome. In populations of European ancestry, nine such haplogroups with frequencies of at least 1% have been described . Emerging evidence suggests that different mtDNA haplogroups are associated with subtle differences in OXPHOS capacity and the generation of ROS [5, 6]. Recent evidence suggests that mtDNA haplogroups have functional consequences, being linked to longevity , sperm motility , certain types of cancer  and affecting the risk of individuals developing specific late-onset neurodegenerative diseases .
Diabetic retinopathy is caused by alterations in the retinal microvasculature leading to breakdown of the blood-retina barrier and pathological angiogenesis  and is one of the primary causes of visual loss worldwide . Diabetic retinopathy and CAD are two vascular complications of type 2 diabetes mellitus, representing examples of microangiopathy and macroangiopathy, respectively. Retinopathy is also an early and frequent sign of other vascular complications and is strongly associated with the development of CAD [12, 13]. This indicates that CAD and diabetic retinopathy share common risk factors and pathological mechanisms, such as diabetes and inflammation, which both exhibit increased ROS production [14, 15].
It has been shown that oxidative stress due to disturbance in the balance between production of ROS and antioxidant defence plays a vital role in the pathogenesis of coronary atherosclerosis and its complications .
We aimed to investigate the association of mtDNA haplogroups with CAD as well as diabetic retinopathy.
Patients and control subjects
Characteristics of the study populations.
Patients with heart disease
Patients with diabetes
Valvular Heart Disease
n = 1527
n = 487
n = 111
n = 78
n = 149
Mean (SD*) age (years)
Mean (SD*) BMI† (kg/m2)
History of myocardial infarction (%)
Diagnosis of diabetes (%)
Former smoker (%)
Current smoker (%)
Patients with heart diseases (n = 598) were recruited in Salzburg and Graz. Four hundred and eighty-seven individuals had angiographically documented CAD with at least one of the main coronary arteries showing ≥ 50% stenosis. CAD was angiographically excluded in 111 patients with valvular heart disease.
The study population of patients with diabetes (n = 227) was recruited at the University Hospital of Graz and consisted of patients with (n = 149) and without diabetic retinopathy (n = 78). Presence and severity of diabetic retinopathy were assessed by fundus examination. Diabetic retinopathy was graded according to the modified "Early Treatment Diabetic Retinopathy Study" (ETDRS) retinopathy scale as no apparent retinopathy, non-proliferative, and proliferative diabetic retinopathy.
The control population consisted of 1527 unrelated individuals as previously described in detail . Briefly, the cohort comprised 988 men between 39 and 66 years of age and 539 women between 39 and 67 years of age who were recruited in the Salzburg Atherosclerosis Prevention Program (SAPHIR) . Exclusion criteria for participation in this study were a history of CAD, heart failure, cerebrovascular disease, peripheral vascular disease, haemodynamically relevant heart valve disease, chronic disease (of liver or kidney, autoimmune disorders, malignant cancer, haematologic disorders, endocrinopathies, diabetes mellitus) and morbid obesity. Laboratory methods have been described previously . The haplogroup frequency in 1172 individuals of the control cohort was reported . The study was approved by the Ethics Committee of the Medical Association of Salzburg.
Venous blood was collected in 5 ml EDTA tubes; total DNA was isolated with a Nucleospin Blood Kit (Macherey-Nagel) and stored at 4°C. A hierarchical system for mtDNA haplogrouping that combines multiplex PCR amplifications, multiplex single-base primer extensions, and capillary-based electrophoretic separation for analysing ten haplogroup-diagnostic mitochondrial SNPs (mtSNPs) was used to determine the haplogroup distribution of the most common European haplogroups H, U, J, T, K, I, V, W and X, as described previously . Haplogroups that could not be assigned to one of the nine major European haplogroups by the SNP combination were designated as "others". From the 2387 subjects investigated, genotyping failed in 0.21% of the samples (n = 5). PCR amplification failed due to degradation of DNA in 1.26% of samples (n = 30).
Frequencies of all mitochondrial haplogroups in CAD patients and in controls were tested for independency using Pearson chi-square statistics and Fisher's exact test as appropriate. Similarly, frequencies of mitochondrial haplogroups were compared between patients with heart disease other than CAD and controls. For further analysis only low frequency haplogroups (K, W, V, I, X) were excluded from further analyses. Age and gender adjusted odds ratios and 95% confidence intervals were then calculated to express the strength of the associations between the haplogroups and phenotypes. The following variables were also considered as potential confounders and tested in logistic regression models: hypertension (yes/no), body mass index (BMI), and smoking (never, former smoker, current smoker). Covariates that had a significance level of less than 0.1 were retained to create the best-fitting model based on Akaike's information criterion. If one category of an independent variable had a significance of 0.1 or less, all parts of the categorical variable were retained in the best-fitting model. P-values were corrected for multiple comparison by Bonferroni analysis (required significance level = 0.05/number of comparisons), leading to a new required significance level of <0.008 [number of comparisons = 6 (3 × 2) for 3 haplogroups compared to haplogroup H and to two diseases (CAD and Valvular Heart Disease)].
The same methods as described above were applied to calculate associations between mitochondrial haplogroups and the presence of retinopathy among patients with diabetes. Sex-adjusted odds ratios and 95% confidence intervals were then tested for the potential confounding effect of age at onset of diabetes (years), duration of diabetes (months), levels of HbA1c (%) measured at the time of recruitment, medication (insulin, oral antidiabetics), history of myocardial infarction (yes/no), and hypertension (yes/no). The best-fitting model was created in the same manner as for the heart disease population. P-values were corrected for multiple comparison by Bonferroni analysis (required significance level = 0.05/number of comparisons), leading to a new required significance level of <0.017 (number of comparisons = 3 for 3 haplogroups compared to haplogroup H).
All analyses were performed using SPSS 15.0 student version (SPSS GmbH Software, 80339 Munich, Germany) and Stata/SE 10.0 (Stata Corporation, College Station, TX, USA).
Frequencies (%) of mitochondrial haplogroups in cases and controls.
Patients with heart diseases
Patients with diabetes
Valvular Heart Disease
n = 1527
n = 487
n = 111
n = 78
n = 149
Odds ratios (OR) and 95% confidence intervals (CI) for the association between mitochondrial haplogroup and CAD and Valvular Heart Disease, respectively.
OR* (95% CI)
aOR† (95% CI)
Coronary artery disease
Valvular Heart disease
Odds ratios (OR) and 95% confidence intervals (CI) for the association between mitochondrial haplogroup and retinopathy in patients with diabetes (n = 179).
OR* (95% CI)
aOR† (95% CI)
Our data show an association of mtDNA haplogroup T with coronary artery disease and diabetic retinopathy. Mitochondrial dysfunction has been implicated in the pathogenesis of several diseases characterised by free radical-induced damage [19–21]. Genetic association of specific mtDNA haplogroups has been demonstrated with aging and multifactorial age-related diseases like Alzheimer's disease, multiple sclerosis and cancer . Although the precise mechanisms underlying the associations of mtDNA haplogroups with multifactorial age-related diseases including CAD and diabetic retinopathy remain speculative, haplogroup-specific differences in free radical production during OXPHOS may be one such mechanism. Thus, presence of haplogroup T might be associated with increased oxidative stress or increased susceptibility to oxidative stress. Individuals carrying haplogroup T might be more vulnerable to oxidative damage than carriers of other haplogroups.
While intracellular ROS serve mainly for host defence against infectious agents, redox-sensitive signal transduction, and other cellular processes, the extracellular release of ROS may damage surrounding tissues, potentially promoting inflammatory processes [23, 24]. ROS are involved in aging and many diseases such as atherosclerosis, cancer, diabetes mellitus, neurological degeneration, and tumor invasion. There is strong evidence that inflammation also plays a major role in the etiology and progression of diabetic retinopathy . Inflammation is an integral part not only of CAD but also of other complex diseases like multiple sclerosis, where an association of mtDNA haplogroups has been reported . Enhanced formation of ROS may affect four fundamental mechanisms that contribute to atherogenesis, namely: oxidation of low density lipoprotein (LDL), endothelial dysfunction, vascular smooth muscle cell growth, and monocyte migration . Interestingly, we did not find an association of haplogroup T to markers of inflammation like C-reactive protein (CRP) and LDL (data not shown).
Previous exact analysis of specific differences in the mtDNA haplogroups revealed that haplogroup T is generally associated with a number of polymorphisms in the non-coding control region (16126, 16294), mitochondrial ribosomal RNAs (709, 1888), mitochondrial transfer RNAs (10463, 15928), several SNPs not changing amino acids in the corresponding proteins, and a polymorphism at position 4917 leading to a change of asparagin to aspartate in the ND2 protein . All these SNPs could contribute to altered OXPHOS performance and ROS production. This hypothesis was substantiated by Ruiz-Pesini et al., who have shown that sperm cells of individuals with haplogroup T have a lower activity of respiratory chain complexes than sperm cells with haplogroup H . In contrast, another study was not able to demonstrate bioenergetic differences of isogenetic cell lines representing haplogroup H and T . Unfortunately alteration of ROS production in these cell lines with different haplogroups has not been reported. We assume that the differences in ROS production among the haplogroups are subtle, requiring both time and interactions with other genetic and environmental factors before pathological manifestation. In accordance with previous studies, we found no association between mtDNA haplogroups and type 2 diabetes mellitus when all patients with diabetes (with and without retinopathy) were included . Epidemiological studies in Japan showed an association of a mtDNA variation (position 5178, haplogroup N9b) with myocardial infarction [29, 30]. We did not investigate the mtDNA variant located at position 5178, which is an indicator for Asian haplogroup D and the N9b haplogroup, because these variations are not prevalent in European Caucasians. Our data, however, support the concept that mtDNA variability is associated with vascular diseases.
A recent study from Denmark found no association of mtDNA haplogroups with ischemic cardiovascular disease, cancer, infectious diseases, longevity and mortality in a general population of northern European descent . The study was perspective, included a large number of individuals with a long follow up. No major association to a wide variety of diseases was observed, although there is a vast literature on the association of mtDNA haplogroups with several diseases available. One explanation could be the different geographical distribution of mtDNA haplogroups. Therefore, our study on a middle European population can not be directly compared with the Danish study. Furthermore, Benn et al. investigated cases with myocardial infarction or symptoms considered characteristic of angina pectoris whereas in our study we included patients with angiographically documented CAD (i.e. ≥ 50% stenosis of at least one of the major epicadial vessels) – a criteria consistently used in the literature defining clinically relevant CAD [32, 33].
We assume that a certain percentage of our control subjects will develop CAD and/or diabetes. This might have led to an underestimation of the effects we observed in the present study. If these persons could have been excluded, then one could expect that the prevalence of haplogroup T would have been even lower than was observed in the present control cohort; this in turn would increase the statistical significance of our findings. When we performed statistical analysis of CAD patients with a similar mean of age as controls, we found that there was an even larger difference in frequencies of haplogroup T between cases and controls (data not shown). We can not exclude that other unknown and unmeasured confounding factors are present.
In the present study, mitochondrial haplogroup T is significantly associated with the presence of CAD and diabetic retinopathy, indicating that the presence of haplogroup T contributes to the risk of developing both CAD and diabetic retinopathy. The association between vascular disease and haplogroup variation of mtDNA, as demonstrated in the present study, should stimulate further investigation on their biological effects as well as on their relations to chronic diseases.
We thank Eva Schwaiger, Katharina Hammerl and Gabriele Kronberger for technical assistance.
The project was supported by the "Medizinische Forschungsgesellschaft Salzburg" and by a grant of the "Kamillo-Eisner Stiftung" to B. Paulweber.
- Gutierrez J, Ballinger SW, Darley-Usmar VM, Landar A: Free radicals, mitochondria, and oxidized lipids: the emerging role in signal transduction in vascular cells. Circ Res. 2006, 99: 924-932. 10.1161/01.RES.0000248212.86638.e9.View ArticlePubMedGoogle Scholar
- DiMauro S, Schon EA: Mitochondrial respiratory-chain diseases. N Engl J Med. 2003, 348: 2656-2668. 10.1056/NEJMra022567.View ArticlePubMedGoogle Scholar
- Wallace DC: A mitochondrial paradigm of metabolic and degenerative diseases, aging, and cancer: a dawn for evolutionary medicine. Annu Rev Genet. 2005, 39: 359-407. 10.1146/annurev.genet.39.110304.095751.View ArticlePubMedPubMed CentralGoogle Scholar
- Torroni A, Petrozzi M, D'Urbano L, Sellitto D, Zeviani M, Carrara F, Carducci C, Leuzzi V, Carelli V, Barboni P, De Negri A, Scozzari R: Haplotype and phylogenetic analyses suggest that one European-specific mtDNA background plays a role in the expression of Leber hereditary optic neuropathy by increasing the penetrance of the primary mutations 11778 and 14484. Am J Hum Genet. 1997, 60: 1107-1121.PubMedPubMed CentralGoogle Scholar
- Ruiz-Pesini E, Lapena AC, Diez-Sanchez C, Perez-Martos A, Montoya J, Alvarez E, Diaz M, Urries A, Montoro L, Lopez-Perez MJ, Enriquez JA: Human mtDNA haplogroups associated with high or reduced spermatozoa motility. Am J Hum Genet. 2000, 67: 682-696. 10.1086/303040.View ArticlePubMedPubMed CentralGoogle Scholar
- Esposito LA, Melov S, Panov A, Cottrell BA, Wallace DC: Mitochondrial disease in mouse results in increased oxidative stress. Proc Natl Acad Sci USA. 1999, 96: 4820-4825. 10.1073/pnas.96.9.4820.View ArticlePubMedPubMed CentralGoogle Scholar
- Rose G, Passarino G, Carrieri G, Altomare K, Greco V, Bertolini S, Bonafe M, Franceschi C, De Benedictis G: Paradoxes in longevity: sequence analysis of mtDNA haplogroup J in centenarians. Eur J Hum Genet. 2001, 9: 701-707. 10.1038/sj.ejhg.5200703.View ArticlePubMedGoogle Scholar
- Darvishi K, Sharma S, Bhat AK, Rai E, Bamezai RN: Mitochondrial DNA G10398A polymorphism imparts maternal Haplogroup N a risk for breast and esophageal cancer. Cancer Lett. 2007, 249: 249-255. 10.1016/j.canlet.2006.09.005.View ArticlePubMedGoogle Scholar
- Pyle A, Foltynie T, Tiangyou W, Lambert C, Keers SM, Allcock LM, Davison J, Lewis SJ, Perry RH, Barker R, Burn DJ, Chinnery PF: Mitochondrial DNA haplogroup cluster UKJT reduces the risk of PD. Ann Neurol. 2005, 57: 564-567. 10.1002/ana.20417.View ArticlePubMedGoogle Scholar
- Aiello LP, Avery RL, Arrigg PG, Keyt BA, Jampel HD, Shah ST, Pasquale LR, Thieme H, Iwamoto MA, Park JE, et al: Vascular endothelial growth factor in ocular fluid of patients with diabetic retinopathy and other retinal disorders. N Engl J Med. 1994, 331: 1480-1487. 10.1056/NEJM199412013312203.View ArticlePubMedGoogle Scholar
- Aiello LP, Gardner TW, King GL, Blankenship G, Cavallerano JD, Ferris FL, Klein R: Diabetic retinopathy. Diabetes Care. 1998, 21: 143-156.View ArticlePubMedGoogle Scholar
- Norgaz T, Hobikoglu G, Aksu H, Guveli A, Aksoy S, Ozer O, Bolca O, Narin A: Retinopathy is related to the angiographically detected severity and extent of coronary artery disease in patients with type 2 diabetes mellitus. Int Heart J. 2005, 46: 639-646. 10.1536/ihj.46.639.View ArticlePubMedGoogle Scholar
- Wong TY, Klein R, Sharrett AR, Manolio TA, Hubbard LD, Marino EK, Kuller L, Burke G, Tracy RP, Polak JF, Gottdiener JS, Siscovick DS: The prevalence and risk factors of retinal microvascular abnormalities in older persons: The Cardiovascular Health Study. Ophthalmology. 2003, 110: 658-666. 10.1016/S0161-6420(02)01931-0.View ArticlePubMedGoogle Scholar
- Brownlee M: The pathobiology of diabetic complications: a unifying mechanism. Diabetes. 2005, 54: 1615-1625. 10.2337/diabetes.54.6.1615.View ArticlePubMedGoogle Scholar
- Madamanchi NR, Runge MS: Mitochondrial dysfunction in atherosclerosis. Circ Res. 2007, 100: 460-473. 10.1161/01.RES.0000258450.44413.96.View ArticlePubMedGoogle Scholar
- Weitgasser R, Galvan G, Malaimare L, Derflinger I, Hedegger M, Lang J, Iglseder B, Ladurner G, Paulweber B: Cholesteryl ester transfer protein TaqIB polymorphism and its relation to parameters of the insulin resistance syndrome in an Austrian cohort. Biomed Pharmacother. 2004, 58: 619-627. 10.1016/j.biopha.2004.09.010.View ArticlePubMedGoogle Scholar
- Wiesbauer M, Meierhofer D, Mayr JA, Sperl W, Paulweber B, Kofler B: Multiplex primer extension analysis for rapid detection of major European mitochondrial haplogroups. Electrophoresis. 2006, 27: 3864-3868. 10.1002/elps.200600086.View ArticlePubMedGoogle Scholar
- Malyarchuk BA, Grzybowski T, Derenko MV, Czarny J, Drobnic K, Miscicka-Sliwka D: Mitochondrial DNA variability in Bosnians and Slovenians. Ann Hum Genet. 2003, 67: 412-425. 10.1046/j.1469-1809.2003.00042.x.View ArticlePubMedGoogle Scholar
- Monsalve M, Borniquel S, Valle I, Lamas S: Mitochondrial dysfunction in human pathologies. Front Biosci. 2007, 12: 1131-1153. 10.2741/2132.View ArticlePubMedGoogle Scholar
- Tan AL, Forbes JM, Cooper ME: AGE, RAGE, and ROS in diabetic nephropathy. Semin Nephrol. 2007, 27: 130-143. 10.1016/j.semnephrol.2007.01.006.View ArticlePubMedGoogle Scholar
- Schleicher E, Friess U: Oxidative stress, AGE, and atherosclerosis. Kidney Int Suppl. 2007, S17-26. 10.1038/sj.ki.5002382.Google Scholar
- Raule N, Sevini F, Santoro A, Altilia S, Franceschi C: Association studies on human mitochondrial DNA: methodological aspects and results in the most common age-related diseases. Mitochondrion. 2007, 7: 29-38. 10.1016/j.mito.2006.11.013.View ArticlePubMedGoogle Scholar
- Duval C, Cantero AV, Auge N, Mabile L, Thiers JC, Negre-Salvayre A, Salvayre R: Proliferation and wound healing of vascular cells trigger the generation of extracellular reactive oxygen species and LDL oxidation. Free Radic Biol Med. 2003, 35: 1589-1598. 10.1016/j.freeradbiomed.2003.09.008.View ArticlePubMedGoogle Scholar
- Kopprasch S, Pietzsch J, Graessler J: Validation of different chemilumigenic substrates for detecting extracellular generation of reactive oxygen species by phagocytes and endothelial cells. Luminescence. 2003, 18: 268-273. 10.1002/bio.737.View ArticlePubMedGoogle Scholar
- Kalman B: Role of mitochondria in multiple sclerosis. Curr Neurol Neurosci Rep. 2006, 6: 244-252. 10.1007/s11910-006-0012-0.View ArticlePubMedGoogle Scholar
- Pike DA: Phylogenetic networks for human mtDNA haplogroup T. J of Genetic Genealogy. 2006, 2: 1-11.Google Scholar
- Amo T, Yadava N, Oh R, Nicholls DG, Brand MD: Experimental assessment of bioenergetic differences caused by the common European mitochondrial DNA haplogroups H and T. Gene. 2008, 411: 69-76. 10.1016/j.gene.2008.01.007.View ArticlePubMedPubMed CentralGoogle Scholar
- Chinnery PF, Mowbray C, Patel SK, Elson JL, Sampson M, Hitman GA, McCarthy MI, Hattersley AT, Walker M: Mitochondrial DNA haplogroups and type 2 diabetes: a study of 897 cases and 1010 controls. J Med Genet. 2007, 44: e80-10.1136/jmg.2007.048876.View ArticlePubMedPubMed CentralGoogle Scholar
- Takagi K, Yamada Y, Gong JS, Sone T, Yokota M, Tanaka M: Association of a 5178C-->A (Leu237Met) polymorphism in the mitochondrial DNA with a low prevalence of myocardial infarction in Japanese individuals. Atherosclerosis. 2004, 175: 281-286. 10.1016/j.atherosclerosis.2004.03.008.View ArticlePubMedGoogle Scholar
- Nishigaki Y, Yamada Y, Fuku N, Matsuo H, Segawa T, Watanabe S, Kato K, Yokoi K, Yamaguchi S, Nozawa Y, Tanaka M: Mitochondrial haplogroup N9b is protective against myocardial infarction in Japanese males. Hum Genet. 2007, 120: 827-836. 10.1007/s00439-006-0269-z.View ArticlePubMedGoogle Scholar
- Benn M, Schwartz M, Nordestgaard BG, Tybjaerg-Hansen A: Mitochondrial haplogroups: ischemic cardiovascular disease, other diseases, mortality, and longevity in the general population. Circulation. 2008, 117: 2492-2501. 10.1161/CIRCULATIONAHA.107.756809.View ArticlePubMedGoogle Scholar
- Lenzen MJ, Boersma E, Bertrand ME, Maier W, Moris C, Piscione F, Sechtem U, Stahle E, Widimsky P, de Jaegere P, Scholte op Reimer WJ, Mercado N, Wijns W: Management and outcome of patients with established coronary artery disease: the Euro Heart Survey on coronary revascularization. Eur Heart J. 2005, 26: 1169-1179. 10.1093/eurheartj/ehi238.View ArticlePubMedGoogle Scholar
- Do D, West JA, Morise A, Atwood E, Froelicher V: A consensus approach to diagnosing coronary artery disease based on clinical and exercise test data. Chest. 1997, 111: 1742-1749. 10.1378/chest.111.6.1742.View ArticlePubMedGoogle Scholar
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2350/10/35/prepub
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