Involvement of growth differentiation factor 15 in paradoxical relationship between body mass index and mortality in patients with suspected or known coronary artery disease; The ANOX Study

Background

Obesity is a well-established risk factor for type 2 diabetes mellitus, hypertension and dyslipidemia, leading to coronary artery disease (CAD). Nevertheless, body mass index (BMI) is inversely associated with cardiovascular (CV) mortality in patients with cardiac disorders, termed “obesity paradox”. However, the underlying mechanism remains unclear.

Purpose

To clarify important factors involved in the pathogenesis of obesity paradox.

Methods

Using data from a multicenter, prospective cohort of 2,418 patients with suspected or known CAD enrolled in the ANOX study, we assessed the relationship between BMI at baseline and the incidence of CV death over 3 years, and investigated the involvement of several endocrine factors which were previously reported to have some roles in obesity and heart diseases, such as adiponectin, N-terminal pro-brain natriuretic peptide (NT-proBNP) and growth differentiation factor 15 (GDF-15), in the relationship between BMI and CV death.

Results

In Kaplan-Meier analyses, the lower quartiles of BMI and the higher quartiles of adiponectin levels were paradoxically associated with the higher cumulative incidence of CV death. To clarify the important factors involved in the paradoxical association between BMI or adiponectin and mortality, we first investigated independent determinants for BMI and adiponectin levels respectively, using multiple stepwise regression analyses among many clinical factors, and then narrow down the prognostic factors commonly associated with BMI and adiponectin, which were age, hemoglobin and NT-proBNP. Interestingly, circulating levels of GDF15 were significantly correlated with NT-proBNP levels, and the presence of anemia raised the gradient of the correlation line in a scatter plot (without anemia, r=0.139, p<0.0001; with anemia, r=0.228, p<0.0001). Moreover, the highest GDF15 quartile showed significantly lower BMI and higher adiponectin levels compared to the lower quartiles (p<0.001 and p<0.001, respectively, by Student t-test). In Cox proportional hazard models, hazard ratios (HRs) of BMI (per 1-unit increase) were 0.90 (95% confidence interval [CI], 0.85–0.96) for CV death. Additional adjustment for hemoglobin, NT-proBNP, adiponectin or GDF15 diminished the statistical significance (HR, 0.92 [95% CI, 0.87–0.99], 0.95 [0.89–1.01], 0.92 [0.87–0.99], or 0.93 [0.87–0.99], respectively).

Conclusions

The lower BMI and the higher adiponectin levels were paradoxically associated with the higher incidence of CV death in patients with CAD. This paradox may be mediated by cardiac endocrine factors induced by cardiac stresses, including GDF-15 in addition to natriuretic peptides.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Associations of soluble fms-like tyrosine kinase-1 with cardiovascular events and stroke in patients with atrial fibrillation and suspected or known coronary artery disease: the EXCEED-J study

Background

Atrial fibrillation (AF) increases the risk of stroke. Soluble fms-like tyrosine kinase-1 (sFlt-1), a vascular endothelial growth factor (VEGF) antagonist, has been suggested as a marker of endothelial dysfunction, which are associated with both AF and coronary artery disease (CAD). Recently, we demonstrated that sFlt-1 is independently associated with major adverse cardiovascular (CV) events (MACE) in patients with suspected or known CAD. However, the prognostic utility of sFlt-1 in patients with AF remains unknown.

Methods

Using data from a multicenter, prospective cohort of 3255 patients with suspected or known CAD, we investigated whether AF modifies the prognostic utility of sFlt-1. Heparin-free serum levels of sFlt-1, N-terminal pro-brain natriuretic peptide, high-sensitivity cardiac troponin-I, high-sensitivity C-reactive protein, cystatin C, neutrophil gelatinase-associated lipocalin, VEGF, and placental growth factor were measured in 324 patients with AF and 2931 patients without AF. The primary outcome was MACE defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke. The secondary outcomes were all-cause death, CV death, stroke, heart failure (HF) hospitalization, and coronary/peripheral artery revascularization. The biomarkers were natural log-transformed for use as continuous variables.

Results

After adjustment for potential clinical confounders including anticoagulant drug use, sFlt-1 was significantly associated with MACE (hazard ratio for 1 standard deviation increase [HR], 1.55; 95% confidence interval [CI], 1.14–2.08), CV death (HR, 1.68; 95% CI, 1.10–2.48), and stroke (HR, 1.89; 95% CI, 1.16–3.10), but not with all-cause death (HR, 1.32; 95% CI, 0.99–1.73), HF hospitalization (HR, 0.97; 95% CI, 0.73–1.25), or revascularization (HR, 0.99; 95% CI, 0.74–1.28) in patients with AF, whereas sFlt-1 was significantly associated with MACE (HR, 1.19; 95% CI, 1.02–1.37), all-cause death (HR, 1.19; 95% CI, 1.05–1.34), CV death (HR, 1.26; 95% CI, 1.03–1.48), and HF hospitalization (HR, 1.26; 95% CI, 1.11–1.42), but not with stroke (HR, 1.06; 95% CI, 0.81–1.33) or revascularization (HR, 1.01; 95% CI, 0.95–1.07) in patients without AF. Among other biomarkers, only VEGF was significantly associated with MACE (HR, 1.55; 95% CI, 1.02–2.44), and no biomarkers were significantly associated with CV death or stroke in patients with AF. sFlt-1 added incremental prognostic information for MACE (P=0.005 for net reclassification improvement [NRI], P=0.026 for integrated discrimination improvement [IDI]) and stroke (P=0.034 for NRI, P=0.018 for IDI), but not for CV death (P=0.021 for NRI, P=0.134 for IDI), to the model with potential clinical confounders in patients with AF.

Conclusions

sFlt-1 independently predicted MACE and stroke in patients with AF and suspected or known CAD. sFlt-1 may serve as a novel prognostic biomarker to stratify the risk of MACE and stroke in patients with AF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Health Labour Sciences Research Grant (2013-2014), AMED (2015-2017, Grant Number JP17ek0210008)

Serum amyloid A-low-density-lipoprotein complex and mortality in patients with suspected or known coronary artery disease: the ANOX study

Background

Serum amyloid A-low-density-lipoprotein (SAA-LDL) is a complex formed from the oxidative interaction between SAA and LDLs. A relatively small-scale study has shown that circulating SAA-LDL levels may serve as a prognostic marker in patients with stable coronary artery disease (CAD). However, the prognostic value of SAA-LDL should be confirmed in a larger-scale cohort study.

Methods

Using data from a multicenter, prospective cohort of 2416 patients with suspected or known CAD enrolled in the ANOX (Development of Novel Biomarkers Related to Angiogenesis or Oxidative Stress to Predict Cardiovascular Events) study, we assessed the prognostic value of serum levels of SAA-LDL. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke. Patients were followed up over 3 years.

Results

Stepwise regression analysis including baseline data on potential clinical confounders (i.e., age, sex, body mass index, hypertension, dyslipidemia, diabetes, current smoking, estimated glomerular filtration rate, the Gensini score, previous myocardial infarction, previous stroke, previous heart failure hospitalization, atrial fibrillation, malignancies, anemia, antihypertensive drug use, statin use, and aspirin use) and established cardiovascular biomarkers (i.e., N-terminal pro-brain natriuretic peptide, high-sensitivity cardiac troponin I [hs-cTnI], and high-sensitivity C-reactive protein [hs-CRP]) revealed that independent determinants of SAA-LDL levels were female sex, dyslipidemia, the Gensini score, absence of statin use, hs-cTnI, and hs-CRP. After adjusting for potential clinical confounders and established cardiovascular biomarkers, the highest quartile of SAA-LDL levels (vs. the lowest quartile) was significantly associated with the incidence of all-cause death (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.02–2.26), but not with that of cardiovascular death (HR, 1.11; 95% CI, 0.59–2.10) or MACE (HR, 1.57; 95% CI, 0.97–2.57). Stratified analyses revealed that this association was pronounced in patients with low hs-cTnI (<75th percentile) (HR, 1.85; 95% CI, 1.06–3.30) and in patients with low hs-CRP levels (≤1.0 mg/L) (HR, 2.30; 95% CI, 1.17–4.79).

Conclusions

Elevated SAA-LDL levels were independently associated with the risk of all-cause death in patients with suspected or known CAD. The SAA-LDL level appears to serve as a prognostic biomarker for risk stratification in relatively low-risk patients with low hs-cTnI (<75th percentile) or low hs-CRP (≤1.0 mg/L).

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Impact of atrial fibrillation on soluble fms-like tyrosine kinase-1 and cardiovascular events in patients with suspected or known coronary artery disease: the EXCEED-J study

Background

Soluble fms-like tyrosine kinase-1 (sFlt-1), a vascular endothelial growth factor (VEGF) antagonist, has been suggested as a marker of endothelial dysfunction. Circulating sFlt-1 levels are associated with adverse outcomes in patients with preeclampsia, chronic kidney disease, and heart failure. Atrial fibrillation (AF) and coronary artery disease (CAD) are both associated with endothelial dysfunction. However, whether sFlt-1 can predict cardiovascular (CV) events and whether AF modifies the relationship between sFlt-1 and CV events in patients with suspected or known CAD are unknown.

Methods

We performed a nationwide, multicenter, prospective cohort study to determine the prognostic value of sFlt-1 and other biomarkers in patients with suspected or known CAD undergoing elective angiography. Heparin-free fasting serum was collected from the peripheral vein to determine levels of sFlt-1, VEGF, placental growth factor, cystatin C, neutrophil gelatinase-associated lipocalin, N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin-I (hs-cTnI), and high-sensitivity C-reactive protein (hs-CRP). The primary outcome was 3-point major adverse CV events (3P-MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke. The secondary outcomes were all-cause death, CV death, and 5P-MACE defined as a composite of 3P-MACE, heart failure hospitalization, and coronary/peripheral artery revascularization.

Results

3311 patients were consecutively enrolled between Nov 2013 and May 2017. After excluding 56 ineligible patients, 3255 patients (324 AF and 2931 non-AF) were followed up over 3 years (follow-up rate, 99%). During the follow-up, 156 patients developed 3P-MACE, 215 died from any cause, 82 died from cardiovascular disease, and 1361 developed 5P-MACE. The sFlt-1 level was significantly higher in AF compared to non-AF patients (p<0.001). Stepwise regression analysis revealed that the sFlt-1 level was independently associated with AF. After adjusting for potential clinical confounders, serum levels of sFlt-1, NT-proBNP, hs-cTnI and cystatin C, but not other biomarkers, were significantly associated with 3P-MACE in the entire cohort. These associations were still significant in non-AF patients, whereas only the sFlt-1 level was significantly associated with 3P-MACE in AF patients. Serum levels of sFlt-1, but not other biomarkers, were also significantly associated with CV death in AF patients. Among the biomarkers, only the hs-CRP level was significantly associated with all-cause death, and no biomarker was significantly associated with 5P-MACE in AF patients. Furthermore, sFlt-1 provided an incremental prognostic information for 3P-MACE to the model with potential clinical confounders in AF, but not in non-AF patients.

Conclusions

Serum levels of sFlt-1 were significantly associated with 3P-MACE in patients with suspected or known CAD. This association was pronounced in AF patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The EXCEED-J study is supported by Health Labour Sciences Research Grant (2013-2014), AMED (2015-2017, Grant Number JP17ek0210008) and Grant-in-Aid for Clinical Research from the National Hospital Organization (2018-2020).

Influence of renal dysfunction on clinical outcomes in elderly patients with atrial fibrillation: a subanalysis of the phase 3, randomized, placebo-controlled ELDERCARE-AF trial

Background

Renal dysfunction is common in elderly patients with atrial fibrillation (AF) and is thought to be associated with increased risk of thromboembolic and bleeding events. Once-daily low-dose (15 mg) edoxaban was superior to placebo in preventing stroke or systemic embolic events (S/SEE) without significantly increasing major bleeding events in very elderly (≥80 years) non-valvular AF (NVAF) patients in whom standard oral anticoagulant therapy at approved doses was inappropriate (ELDERCARE-AF trial). Little is known about how renal dysfunction affects the effects of low-dose edoxaban in these patients.

Purpose

We used prespecified subgroup analysis to investigate the relation between renal function (assessed by creatinine clearance, CrCl) and the efficacy and safety of edoxaban in elderly NVAF patients.

Methods

ELDERCARE-AF patients were divided into 3 subgroups according to baseline CrCl: normal renal function/mild dysfunction (CrCl >50 mL/min), moderate renal dysfunction (CrCl ≥30 to ≤50 [“30–50”] mL/min) and severe renal dysfunction (CrCl ≥15 to <30 [“15–30”] mL/min). Primary efficacy and safety endpoints were annualized incidence of S/SEE and ISTH-defined major bleeding, respectively.

Results

Of 984 patients randomized to edoxaban 15 mg or placebo (each group N=492), 681 completed the trial. The 303 discontinuations were due to withdrawal of consent (n=158), death (n=135), or other causes (n=10). Discontinuation rate was the same in the edoxaban and placebo groups. S/SEE incidence in patients with CrCl >50, 30–50 and 15–30 mL/min was 2.0%, 1.3% and 3.5%, respectively, in edoxaban, and 4.4%, 4.6% and 9.7%, respectively, in placebo. In those with CrCl 30–50 and 15–30 mL/min, it was significantly lower in edoxaban than in placebo (adjusted hazard ratio [HR], 0.30 [95% CI, 0.10–0.91], p=0.03; and 0.33 [95% CI, 0.16–0.71], p<0.01, respectively). Incidence of major bleeding in patients with CrCl >50, 30–50 and 15–30 mL/min was 1.0%, 1.8% and 6.2%, respectively, in edoxaban, and 0.9%, 1.5% and 2.4%, respectively, in placebo. Incidence of major bleeding in those with CrCl 15–30 mL/min was higher in edoxaban but not significantly (adjusted HR, 2.53 [95% CI, 0.96–6.72], p=0.062). Incidence of gastrointestinal bleeding in patients with CrCl 15–30 mL/min was 4.3% in edoxaban and 1.6% in placebo (adjusted HR, 2.61 [95% CI, 0.79–8.68], p=0.12). Incidence of all-cause death in patients with CrCl >50, 30–50 and 15–30 mL/min was 5.8%, 6.8% and 15.2%, respectively, in edoxaban, and 7.0%, 6.3% and 15.5%, respectively, in placebo (no significant intergroup differences).

Conclusions

Incidence of S/SEE, major bleeding and all-cause death increased with declining renal function in elderly NVAF patients. Edoxaban 15 mg remained superior to placebo in preventing S/SEE, even in those with moderate to severe renal dysfunction. Incidence of major bleeding in patients with severe renal dysfunction was higher (non-significantly) with edoxaban than with placebo.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Daiichi-Sankyo Co., Ltd.

Impact of glucose tolerance status on the relationship between vascular endothelial growth factor D and mortality in patients with suspected coronary artery disease: a subanalysis of the ANOX study

Background

Vascular endothelial growth factor D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 and VEGFR-2. VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to coronary artery disease (CAD). We recently reported that serum levels of VEGF-D are independently associated with mortality in patients with suspected or known CAD. However, the impact of glucose tolerance status on the relationship between VEGF-D and mortality in patients with suspected CAD is unclear.

Methods

Serum VEGF-D levels were measured in 1,717 patients with suspected CAD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict CV events (ANOX) study, and followed up for 3 years. After excluding 67 patients with no HbA1c data, 1,650 patients were divided into 3 groups according to the glucose tolerance status: diabetes (DM, n=693), prediabetes (preDM, n=541) defined as an HbA1c of 5.7 to 6.4%, and normal glucose tolerance (NGT, n=416) defined as an HbA1c of 5.6% or less. The outcomes were total death, CV death, and major adverse CV events (MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 80 DM, 45 preDM, and 30 NGT patients died from any cause, 24 DM, 13 preDM, and 12 NGT died from CV disease, and 54 DM, 30 preDM, and 19 NGT developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with total death (hazard ratio [HR] for 1-SD increase, 1.28; 95% confidence interval [CI], 1.12–1.47), but not with CV death (HR, 1.20; 95% CI, 0.93–1.52) or MACE (HR, 1.23; 95% CI, 0.997–1.48) in DM; VEGF-D levels were not significantly associated with total death (HR, 0.97; 95% CI, 0.70–1.34), CV death (HR, 1.39; 95% CI, 0.92–2.11), or MACE (HR, 1.09; 95% CI, 0.74–1.50) in preDM; VEGF-D levels were not significantly associated with total death (HR, 1.34; 95% CI, 0.98–1.84), CV death (HR, 1.32; 95% CI, 0.78–2.13), or MACE (HR, 1.01; 95% CI, 0.66–1.46) in NGT. Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of total death (P=0.040 for continuous net reclassification improvement [NRI], P=0.007 for integrated discrimination improvement [IDI]), but not that of CV death or MACE in DM, while it did not significantly improved the prediction of total death, CV death, or MACE either in preDM or in NGT.

Conclusions

The VEGF-D level was independently associated with total death in DM, but not in preDM or in NGT. The relationship between VEGF-D and total mortality may depend on the presence of DM in patients with suspected CAD.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Impact of anemia on the relationship between vascular endothelial growth factor C and mortality in patients with suspected or known coronary artery disease: a subanalysis of the ANOX study

Background

The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular (CV) disease. Recently, we demonstrated that serum levels of vascular endothelial growth factor C (VEGF-C), a central player of lymphangiogenesis, are inversely and independently associated with the risk of all-cause mortality in patients with suspected or known coronary artery disease (CAD). However, the impact of anemia on the relationship between VEGF-C and mortality in those patients is unclear.

Methods

Serum VEGF-C levels were measured in 2,418 patients with suspected or known CAD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict CV events (ANOX) study, and followed up for 3 years. Anemia was defined as a hemoglobin level of less than 13 g/dL in men and <12 g/dL in women. Patients were divided into 2 groups according to the presence (anemic, n=882) or absence (non-anemic, n=1,536) of anemia. The primary outcome was all-cause death. The secondary outcomes were CV death, and major adverse CV events (MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 164 anemic and 90 non-anemic patients died from any cause, 64 anemic and 24 non-anemic patients died from CV disease, and 96 anemic and 69 non-anemic patients developed MACE. After adjustment for established risk factors, VEGF-C levels were significantly and inversely associated with all-cause death (hazard ratio [HR] for 1-SD increase, 0.71; 95% confidence interval [CI], 0.59–0.84), CV death (HR, 0.60; 95% CI, 0.44–0.79), and MACE (HR, 0.76; 95% CI, 0.60–0.95) in anemic, while VEGF-C levels were not significantly associated with all-cause death (HR, 0.87; 95% CI, 0.69–1.11), CV death (HR, 1.32; 95% CI, 0.85–1.93), or MACE (HR, 1.12; 95% CI, 0.87–1.42) in non-anemic patients. Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-C levels further improved the prediction of all-cause death (P<0.001 for continuous net reclassification improvement [NRI], P=0.006 for integrated discrimination improvement [IDI]) and CV death (P<0.001 for NRI, P=0.005 for IDI), but not that of MACE (P=0.021 for NRI, P=0.059 for IDI) in anemic, whereas the addition of VEGF-C levels did not improved the prediction of all-cause death (P=0.234 for NRI, P=0.415 for IDI), CV death (P=0.190 for NRI, P=0.392 for IDI) or MACE (P=0.897 for NRI, P=0.128 for IDI) in non-anemic patients.

Conclusions

The VEGF-C level was inversely and independently associated with all-cause and CV mortality in anemic, but not in non-anemic patients with suspected or known CAD. The inverse relationship between VEGF-C and mortality may depend on the presence of anemia.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Impact of chronic kidney disease on the relationship between vascular endothelial growth factor C and mortality in patients with suspected coronary artery disease: a subanalysis of the ANOX study

Background

The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular (CV) disease. Recently, we demonstrated that serum levels of vascular endothelial growth factor C (VEGF-C), a central player of lymphangiogenesis, are inversely and independently associated with the risk of all-cause mortality in patients with suspected or known coronary artery disease (CAD). However, the impact of chronic kidney disease (CKD) on the relationship between VEGF-C and mortality in patients with suspected CAD is unclear.

Methods

Serum VEGF-C levels were measured in 1,717 patients with suspected but no history of CAD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict CV events (ANOX) study, and followed up for 3 years. Patients were divided into 2 groups according to the presence (CKD, n=674) or absence (non-CKD, n=1,043) of CKD. The primary outcome was all-cause death. The secondary outcomes were CV death, and major adverse CV events (MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 95 CKD and 66 non-CKD patients died from any cause, 37 CKD and 13 non-CKD died from CV disease, and 61 CKD and 43 non-CKD developed MACE. After adjustment for established risk factors, VEGF-C levels were significantly and inversely associated with all-cause death (hazard ratio [HR] for 1-SD increase, 0.72; 95% confidence interval [CI], 0.57–0.90) and CV death (HR, 0.69; 95% CI, 0.48–0.97), but not with MACE (HR, 0.78; 95% CI, 0.60–1.03) in CKD, while VEGF-C levels were significantly and inversely associated with all-cause death (HR, 0.69; 95% CI, 0.52–0.91), but not with CV death (HR, 0.91; 95% CI, 0.50–1.66) or MACE (HR, 1.09; 95% CI, 0.81–1.44) in non-CKD. Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-C levels further improved the prediction of all-cause death (P=0.047 for continuous net reclassification improvement [NRI], P=0.048 for integrated discrimination improvement [IDI]), but not that of CV death (P=0.016 for NRI, P=0.245 for IDI) or MACE (P=0.166 for NRI, P=0.311 for IDI) in CKD, whereas the addition of VEGF-C levels did not improve the prediction of all-cause death (P=0.053 for NRI, P=0.012 for IDI), CV death (P=0.864 for NRI, P=0.602 for IDI) or MACE (P=0.999 for NRI, P=0.154 for IDI) in non-CKD.

Conclusions

The VEGF-C level inversely and independently predicted all-cause mortality in CKD, but not in non-CKD patients with suspected CAD. The inverse relationship between VEGF-C and all-cause mortality in patients with suspected CAD seems to be remarkable in the presence of CKD.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Impact of anemia on the relationships of growth differentiation factor 15 with mortality and cardiovascular events in patients with suspected or known coronary artery disease: the ANOX study

Background

Growth differentiation factor 15 (GDF-15) is a stress-responsive cytokine that plays an important role in the regulation of the inflammatory response, growth and cell differentiation. An elevated GDF-15 was found in various conditions including anemia and stable coronary artery disease (CAD), and it was reported to predict mortality and cardiovascular (CV) events in general population and in patients with established CAD. However, the impact of anemia on the relationships of GDF-15 with mortality and CV events in patients with suspected or known CAD is unclear.

Methods

Serum GDF-15 levels were measured in 2,418 patients with suspected or known CAD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict CV events (ANOX) study, and followed up for 3 years. Anemia was defined as a hemoglobin level of less than 13 g/dL in men and <12 g/dL in women. Patients were divided into 2 groups according to the presence (anemic, n=882) or absence (non-anemic, n=1,536) of anemia. The primary outcome was all-cause death. The secondary outcomes were CV death, and major adverse CV events (MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 164 anemic and 90 non-anemic patients died from any cause, 64 anemic and 24 non-anemic patients died from CV disease, and 96 anemic and 69 non-anemic patients developed MACE. After adjustment for established risk factors, GDF-15 levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.75; 95% confidence interval [CI], 1.51–2.04), CV death (HR, 1.67; 95% CI, 1.30–2.13), and MACE (HR, 1.46; 95% CI, 1.18–1.81) in anemic, while GDF-15 levels were also significantly associated with all-cause death (HR, 1.47; 95% CI, 1.27–1.69), CV death (HR, 1.56; 95% CI, 1.18–1.99), and MACE (HR, 1.25; 95% CI, 1.004–1.50) in non-anemic patients. Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of GDF-15 levels further improved the prediction of all-cause death (P<0.001 for continuous net reclassification improvement [NRI], P<0.001 for integrated discrimination improvement [IDI]), CV death (P=0.026 for NRI, P=0.023 for IDI), and MACE (P=0.025 for NRI, P=0.042 for IDI) in anemic, whereas it did not improved the prediction of all-cause death (P=0.072 for NRI, P=0.079 for IDI), CV death (P=0.289 for NRI, P=0.179 for IDI) or MACE (P=0.397 for NRI, P=0.230 for IDI) in non-anemic patients.

Conclusions

The GDF-15 level significantly improved the prediction of all-cause death, CV death, and MACE in anemic, but not in non-anemic patients with suspected or known CAD. The relationships of GDF-15 with mortality and CV events seem to be remarkable in the presence of anemia.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Impact of smoking status on the relationships of growth differentiation factor 15 with mortality and cardiovascular events in patients with suspected or known coronary artery disease: the ANOX study

Background

Growth differentiation factor 15 (GDF-15) is a stress-responsive cytokine that plays an important role in the regulation of the inflammatory response, growth and cell differentiation. An elevated GDF-15 was found in various conditions including cigarette smoking and stable coronary artery disease (CAD), and it was reported to predict mortality and cardiovascular (CV) events in general population and in patients with established CAD. However, the impact of smoking status on the relationships of GDF-15 with mortality and CV events in patients with suspected or known CAD is unclear.

Methods

Serum GDF-15 levels were measured in 2,418 patients with suspected or known CAD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict CV events (ANOX) study, and followed up for 3 years. Patients were divided into 3 groups according to the smoking status: current (n=428), past (n=1,035), and never smokers (n=955). The outcomes were total death, CV death, and major adverse CV events (MACE) defined as a composite of CV death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 48 current, 120 past, and 86 never smokers died from any cause, 17 current, 47 past, and 24 never smokers died from CV disease, and 35 current, 80 past, and 50 never smokers developed MACE. After adjustment for established risk factors, GDF-15 levels were significantly associated with total death (hazard ratio [HR] for 1-SD increase, 1.30; 95% confidence interval [CI], 1.03–1.65), but not with CV death (HR, 1.09; 95% CI, 0.69–1.62) or MACE (HR, 0.95; 95% CI, 0.64–1.34) in current smokers; GDF-15 levels were significantly associated with total death (HR, 1.73; 95% CI, 1.46–2.05) and CV death (HR, 1.41; 95% CI, 1.09–1.85), but not with MACE (HR, 1.20; 95% CI, 0.96–1.48) in past smokers; GDF-15 levels were significantly associated with total death (HR, 1.62; 95% CI, 1.32–1.95), CV death (HR, 1.76; 95% CI, 1.22–2.46), and MACE (HR, 1.64; 95% CI, 1.27–2.07) in never smokers. Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of GDF-15 levels further improved the prediction of total death (P<0.001 for continuous net reclassification improvement [NRI], P=0.001 for integrated discrimination improvement [IDI]) and MACE (P<0.001 for NRI, P=0.045 for IDI), but not that of CV death, in never smokers, while it did not significantly improved the prediction of total death, CV death, or MACE either in current or in past smokers.

Conclusions

The GDF-15 level was independently associated with total death and MACE in never, but not in current or past smokers with suspected or known CAD. The relationships of GDF-15 with mortality and CV events seem to be attenuated by the presence of current and past smoking.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

P1645Vascular endothelial growth factor-D and mortality in suspected or known coronary heart disease patients with a history of heart failure: a subanalysis of the ANOX study

Background

Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to coronary heart disease (CHD). Recent studies suggest that VEGF-D appears to be a biomarker of pulmonary congestion and heart failure in both dyspnea patients and the general population. However, the prognostic value of VEGF-D in suspected or known CHD patients with a history of heart failure is unknown.

Methods

Serum VEGF-D levels were measured in 253 suspected or known CHD patients with a history of heart failure undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 54 patients died from any cause, 24 died from cardiovascular disease, and 35 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.44; 95% confidence interval [CI], 1.18–1.75), cardiovascular death (HR, 1.73; 95% CI, 1.32–2.25), and MACE (HR, 1.49; 95% CI, 1.14–1.89). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.471; 95% CI, 0.176–0.766; P=0.002; integrated discrimination improvement [IDI], 0.036; 95% CI, 0.008–0.064; P=0.011) and cardiovascular death (NRI, 0.722; 95% CI, 0.326–1.118; P<0.001; IDI, 0.063; 95% CI, 0.005–0.122; P=0.033), but not that of MACE (NRI, 0.453; 95% CI, 0.100–0.805; P=0.012; IDI, 0.028; 95% CI, −0.007–0.063; P=0.116).

Conclusions

In suspected or known CHD patients with a history of heart failure undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause and cardiovascular mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

P3639Vascular endothelial growth factor-C and mortality in patients with suspected but no history of coronary heart disease: a subanalysis of the ANOX study

Background

The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular disease. Recently, we demonstrated that serum levels of vascular endothelial growth factor-C (VEGF-C), a central player of lymphangiogenesis, are inversely and independently associated with the risk of all-cause mortality in patients with suspected or known coronary heart disease (CHD). However, the prognostic value of VEGF-C in patients with suspected but no history of CHD is still unclear.

Methods

Serum VEGF-C levels were measured in 1,717 patients with suspected but no history of CHD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 161 patients died from any cause, 50 died from cardiovascular disease, and 104 developed MACE. After adjustment for established risk factors, VEGF-C levels were significantly and inversely associated with all-cause death (hazard ratio [HR] for 1-SD increase, 0.69; 95% confidence interval [CI], 0.58–0.83) and cardiovascular death (HR, 0.72; 95% CI, 0.52–0.998), but not with MACE (HR, 0.91; 95% CI, 0.74–1.13). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-C levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.282; 95% CI, 0.121–0.443; P<0.001; integrated discrimination improvement [IDI], 0.009; 95% CI, 0.003–0.016; P=0.005), but not that of cardiovascular death (NRI, 0.178; 95% CI, r=−0.103–0.458; P=0.214; IDI, 0.004; 95% CI, r=−0.002–0.009; P=0.194) or MACE (NRI, 0.037; 95% CI, r=−0.162–0.235; P=0.717; IDI, 0.000; 95% CI, r=−0.0004–0.0005; P=0.872).

Conclusions

In patients with suspected but no history of CHD undergoing elective coronary angiography, a low VEGF-C value may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization

5195Growth differentiation factor-15 and mortality in suspected or known coronary heart disease patients with diabetes: a subanalysis of the ANOX study

Background

Diabetes is a risk factor for coronary heart disease (CHD), but further risk stratification in patients with diabetes is necessary to improve the prediction and prevention of cardiovascular events and deaths. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine, which plays an important role in the regulation of the inflammatory response, growth and cell differentiation. Elevated GDF-15 was found in various diseases including diabetes and stable CHD, and was reported to predict mortality and cardiovascular events in general or established CHD population. However, the prognostic value of GDF-15 in suspected or known CHD patients with diabetes is unknown.

Methods

Serum GDF-15 levels were measured in 1,087 suspected or known CHD patients with diabetes undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 147 patients died from any cause, 47 died from cardiovascular disease, and 94 developed MACE. After adjustment for established risk factors, GDF-15 levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.66; 95% confidence interval [CI], 1.48–1.86), cardiovascular death (HR, 1.63; 95% CI, 1.34–1.99), and MACE (HR, 1.41; 95% CI, 1.20–1.65). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of GDF-15 levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.344; 95% CI, 0.172–0.517; P<0.001; integrated discrimination improvement [IDI], 0.049; 95% CI, 0.026–0.072; P<0.001), but not that of cardiovascular death (NRI, −0.013; 95% CI, −0.300–0.274; P=0.931; IDI, 0.023; 95% CI, 0.003–0.043; P=0.026) or MACE (NRI, 0.059; 95% CI, −0.151–0.268; P=0.583; IDI, 0.005; 95% CI, −0.004–0.015; P=0.244).

Conclusions

In suspected or known CHD patients with diabetes undergoing elective coronary angiography, elevated GDF-15 levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

P5529Vascular endothelial growth factor-D and mortality in suspected or known coronary heart disease patients with diabetes: a subanalysis of the ANOX study

Background

Diabetes is a risk factor for coronary heart disease (CHD), but further risk stratification in patients with diabetes is necessary to improve the prediction and prevention of cardiovascular events and deaths. Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to CHD. VEGF-D signaling has been used as a therapeutic target of human diseases such as lymphangioleiomyomatosis and refractory angina. Furthermore, in clinical settings, the VEGF-D level is already established as a diagnostic biomarker for lymphangioleiomyomatosis. However, the prognostic value of VEGF-D in suspected or known CHD patients with diabetes is unknown.

Methods

Serum VEGF-D levels were measured in 1,087 suspected or known CHD patients with diabetes undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 147 patients died from any cause, 47 died from cardiovascular disease, and 94 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.34; 95% confidence interval [CI], 1.21–1.47), cardiovascular death (HR, 1.40; 95% CI, 1.18–1.62), and MACE (HR, 1.22; 95% CI, 1.07–1.40). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.258; 95% CI, 0.088–0.429; P=0.003; integrated discrimination improvement [IDI], 0.013; 95% CI, 0.002–0.024; P=0.022), but not that of cardiovascular death (NRI, 0.046; 95% CI, −0.245–0.336; P=0.759; IDI, 0.013; 95% CI, −0.005–0.031; P=0.146) or MACE (NRI, 0.064; 95% CI, −0.146–0.274; P=0.552; IDI, 0.001; 95% CI, −0.002–0.004; P=0.557).

Conclusions

In suspected or known CHD patients with diabetes undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization

P5526Vascular endothelial growth factor-D and mortality in suspected or known coronary heart disease patients with chronic kidney disease: a subanalysis of the ANOX study

Background

Chronic kidney disease (CKD) is an independent risk factor for the development and progression of coronary heart disease (CHD). Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to CHD. VEGF-D signaling has been used as a therapeutic target of human diseases such as lymphangioleiomyomatosis and refractory angina. Furthermore, in clinical settings, the VEGF-D level is already established as a diagnostic biomarker for lymphangioleiomyomatosis. However, the prognostic value of VEGF-D in suspected or known CHD patients with CKD is unknown.

Methods

Serum VEGF-D levels were measured in 999 suspected or known CHD patients with CKD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 154 patients died from any cause, 61 died from cardiovascular disease, and 96 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.41; 95% confidence interval [CI], 1.27–1.56), cardiovascular death (HR, 1.48; 95% CI, 1.28–1.71), and MACE (HR, 1.34; 95% CI, 1.18–1.53). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.272; 95% CI, 0.100–0.445; P=0.002; integrated discrimination improvement [IDI], 0.015; 95% CI, 0.003–0.027; P=0.013), but not that of cardiovascular death (NRI, 0.230; 95% CI, −0.029 to 0.488; P=0.082; IDI, 0.012; 95% CI, −0.007 to 0.031; P=0.207) or MACE (NRI, 0.102; 95% CI, −0.106 to 0.310; P=0.337; IDI, 0.005; 95% CI, −0.005 to 0.015; P=0.337).

Conclusions

In suspected or known CHD patients with CKD undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization

P3765Low vascular endothelial growth factor-C was a predictor for cardiovascular events in patients with atrial fibrillation and suspected or known coronary artery disease: a subanalysis of the ANOX study

Background

Lymphatic system has been considered to play an important role in cardiovascular disease. We recently reported that vascular endothelial growth factor-C (VEGF-C), a central player in lymphangiogenesis, predicted all-cause mortality in patients with suspected or known coronary artery disease (CAD). However, relationship between VEGF-C and atrial fibrillation (AF) remains unclear.

Methods

The ANOX study is a multicenter, prospective cohort study of 2,418 patients with suspected CAD, to determine the predictive value of possible novel biomarkers related to angiogenesis or oxidative stress for major adverse cardiovascular events (MACE) among patients undergoing elective angiography. Blood samples were collected from the arterial catheter sheath at the beginning of coronary angiography. Serum levels of VEGF-C, as well as N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity troponin-I (cTnI), and high-sensitivity C-reactive protein (hsCRP), were measured. The outcome was a MACE defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

Of a total of 2,418 patients, 261 patients had AF at baseline. AF group were older, and had more chronic kidney disease, history of heart failure, and history of stroke, but less diabetes, dyslipidemia, and CAD. The median level of NT-proBNP, cTnI, and hsCRP were higher in AF group [AF vs non-AF: NT-proBNP, 1048 pg/ml vs 162 pg/ml (p<0.0001); cTnI, 0.0003 ng/ml, vs 0.0 ng/ml (p<0.0001); hsCRP, 1.43 ug/ml vs 0.88 ug/ml (p=0.0005)], whereas median level of VEGF-C was lower in AF group [3107 pg/ml vs 3590 pg/ml (p<0.0001)]. AF was associated with lower VEGF-C and higher hsCRP after adjustment for potential confounders. During the 3-year follow-up, 29 (11.1%) patients in AF group and 136 (6.3%) patients in non-AF group developed MACE (p=0.007). Incidence of stroke was higher in AF group (17 (6.5%) vs 52 (2.4%); p<0.0009), despite that the incidence of cardiovascular death and myocardial infarction were similar between the groups. We divided the entire cohort into two groups based on the lowest quartile of VEGF-C or highest quartile of other biomarkers, lowest quartile of VEGF-C (log rank p=0.0004), as well as highest quartile of cTnI (log rank p=0.0009), were significantly associated with MACE in AF group. After adjustment for established risk factors and these biomarkers, both lowest quartile of VEGF-C (HR, 2.73; 95% CI, 1.27–6.06) and highest quartile of cTnI (HR, 2.54; 95% CI, 1.08–6.09) were significantly associated with MACE in AF group.

Conclusions

AF was associated with lower level of VEGF-C, and low VEGF-C as well as high cTnI might serve as an independent predictor of MACE in patients with AF and suspected or known CAD.

P3635Vascular endothelial growth factor-D and mortality in patients with suspected but no history of coronary heart disease: a subanalysis of the ANOX study

Background

Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to coronary heart disease (CHD). VEGF-D signaling has been used as a therapeutic target of human diseases such as lymphangioleiomyomatosis and refractory angina. In clinical settings, the VEGF-D level is already established as a diagnostic biomarker for lymphangioleiomyomatosis. However, the prognostic value of VEGF-D in patients with suspected but no history of CHD is unknown.

Methods

Serum VEGF-D levels were measured in 1,717 patients with suspected but no history of CHD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 161 patients died from any cause, 50 died from cardiovascular disease, and 104 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.29; 95% confidence interval [CI], 1.17–1.42), cardiovascular death (HR, 1.37; 95% CI, 1.20–1.56), and MACE (HR, 1.22; 95% CI, 1.08–1.37). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.165; 95% CI, 0.004–0.325; P=0.044; integrated discrimination improvement [IDI], 0.012; 95% CI, 0.002–0.023; P=0.013), but not that of cardiovascular death (NRI, 0.078; 95% CI, r=−0.203–0.359; P=0.586; IDI, 0.014; 95% CI, r=−0.009–0.037; P=0.235) or MACE (NRI, r=−0.011; 95% CI, r=−0.207–0.184; P=0.337; IDI, 0.003; 95% CI, r=−0.003–0.009; P=0.354).

Conclusions

In patients with suspected but no history of CHD undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

Beneficial effect of troglitazone, an insulin-sensitizing antidiabetic agent, on coronary circulation in patients with non-insulin-dependent diabetes mellitus

Evidence is increasing for small vessel remodeling and disturbance of endothelium-dependent vasodilation in diabetic patients. Insulin increases vascular wall thickening and produces endothelial dysfunction. Troglitazone, a new insulin-sensitizer antidiabetic agent, is considered to reduce plasma insulin level and the present study assessed its effect on the coronary circulation of the patients with non-insulin-dependent diabetes mellitus (NIDDM). Analysis of the myocardial washout rate with adenosine triphosphate-stress thallium-201 scintigraphy was used to estimate coronary circulation, and for estimation of insulin sensitivity, the homeostasis model insulin resistance index (HOMA-R) was calculated. Patients were treated with monotherapy of either troglitazone (200 mg bid, n=12) or glibenclamide (2.5 mg daily, n=12) for 3 months. Age-, sex- and risk factors-matched subjects without NIDDM were employed as a control. Fasting plasma glucose and hemoglobin A1c were similarly decreased by troglitazone or glibenclamide. Plasma insulin level (pmol/L) decreased from 66.6+/-10.8 to 39.0+/-7.2 with troglitazone, but was unchanged by glibenclamide (58.8+/-7.2 to 66.0+/-10.8). The diabetic groups had a significantly lower washout rate than controls, which was improved by troglitazone, but not by glibenclamide. In addition, the increase in washout rate correlated significantly with the decrease in HOMA-R in the troglitazone group. In conclusion, troglitazone can restore coronary circulation by improving insulin resistance in patients with NIDDM.

[Impact of high remnant-like lipoproteins on the function of peripheral arterial endothelium in patients with hyperlipidemia and normolipidemia: estimation using Doppler flow analysis]

OBJECTIVES

Cholesterol levels of remnant-like lipoprotein (RLP-cholesterol: RLP-C), which reflect remnant lipoproteins, are associated with coronary arterial endothelial functions and cardiovascular events. The influence of RLP-C on peripheral vascular endothelial functions in patients with hyperlipidemia and normolipidemia was evaluated based on the reactivity of the antecubital artery to acetylcholine (Ach) and isosorbide dinitrate (ISDN) using a Doppler guidewire.

METHODS

Protocol 1: Five patients were selected, and the dose-response of the antecubital artery was evaluated by administering Ach (0.5, 5, and 50 micrograms/30 sec) or ISDN (0.025, 0.25, and 2.5 mg/30 sec). An index of vascular reactivity (brachial artery response: BR) was determined by dividing the maximal blood flow velocity after the administration of Ach or ISDN by resting blood flow velocity. Protocol 2: BR was evaluated in 48 patients after administering Ach 50 micrograms or ISDN 2.5 mg. Subsequently, these patients were divided into the following three groups based on early morning RLP-C levels: Group L (n = 11), RLP-C < 2.0 mg/dl (minimal detectable level); Group M (n = 21), 2.0 mg/dl < or = RLP-C < 5.0 mg/dl; and Group H (n = 16), 5.0 mg/dl < or = RLP-C. The factors that regulate BR-Ach 50 micrograms were also evaluated in 34 normolipidemic patients.

RESULTS

Protocol 1: BR dose-dependently increased after the administration of Ach and ISDN. Protocol 2: BR-Ach 50 micrograms was significantly less in Group H (3.1 +/- 0.8) than in Groups M (3.8 +/- 0.9, p < 0.03) and L (4.2 +/- 0.9, p < 0.01). However, there were no significant differences in BR-ISDN 2.5 mg between the three groups. Univariate analysis in normolipidemic patients revealed that BR-Ach 50 micrograms was correlated with age (r = -0.355, p < 0.05), RLP-C (r = -0.488, p < 0.01), low-density lipoprotein cholesterol (r = -0.382, p < 0.03), systolic blood pressure (r = -0.354, p < 0.05), and diastolic blood pressure (r = -0.406, p < 0.02). Multivariate analysis using these five factors as independent variables revealed that age, RLP-C, and low-density lipoprotein cholesterol regulated BR-Ach 50 micrograms.

CONCLUSIONS

Peripheral vascular endothelial dysfunction may occur in patients with high levels of RLP-C. RLP-C is an independent lipid factor that regulates peripheral vascular endothelial functions even in normolipidemic patients.

Subacute and chronic effects of DDD pacing on left ventricular diastolic function in patients with non-obstructive hypertrophic cardiomyopathy

The present study examined the ability of dual-chamber (DDD) pacing to improve symptoms and exercise tolerance in patients with non-obstructive hypertrophic cardiomyopathy (HNCM). Seven patients with HNCM who had failed to benefit from pharmacotherapy participated in the study. The New York Heart Association (NHYA) functional class status and exercise tolerance, which was determined by the treadmill exercise test, were recorded and an echocardiographic observation was performed before, and 1 week, 3 months and 1 year after the implantation of a permanent DDD pacemaker. The atrioventricular delay (AVd) was determined by measuring the point of peak rapid filling velocity and maximum cardiac output (CO). Two patients were not implanted with a permanent pacemaker because their CO and blood pressure decreased or because palpitation occurred during temporary pacing. The ratio between early and late peaks of flow velocity (1.56, 1.21,0.95, and 0.86 before implantation and 1 week, 3 months and 1 year after implantation, respectively); deceleration time (ms: 263.2, 217.6, 204.6, 187.0); peak filling rate (ml/s: 146.2, 204.0, 233.2, 243.6); NYHA functional class status (2.0, 1.8, 1.6, 1.4); and exercise tolerance (s: 203, 264, 403, 480) were significantly improved after implantation. However, left ventricular dimension, percent fractional shortening, ejection fraction, acceleration time and the isovolumic relaxation time were not changed significantly. In conclusion, DDD pacing improved symptoms and the NYHA functional class status, which is associated with improvement of left ventricular diastolic function. It is proposed that DDD pacing would be useful in patients not only with obstructive but also non-obstructive hypertrophic cardiomyopathy refractory to medical treatment, depending on the careful selection of subjects.

Metabolism of hepatocyte growth factor in the heart in patients with coronary artery disease: implication for coronary arteriosclerosis

PURPOSE

HGF, one of endothelium-specific growth factors, might contribute to the repair process of vascular endothelial cell damage, suggesting that serum HGF concentration may be elevated in patients with arteriosclerosis. However, the cardiac metabolism of HGF has not been examined in patients with coronary artery disease (CAD). We examined the levels of hepatocyte growth factor (HGF) in the coronary circulation and its correlation with the severity of arteriosclerosis in patients with CAD.

METHODS

We measured serum HGF concentration obtained from the coronary sinus (CS) and ascending aorta (AA) in patients with atherosclerotic CAD (Group E, n = 33) or vasospastic angina (Group V, n = 26), or normal control subjects (Group N, n = 12). In Group E, the severity of coronary artery stenosis was evaluated using the Gensini's score.

RESULTS

Serum HGF concentrations (ng ml) in the CS were 0.112 +/- 0.008 in Group E (p < 0.001 vs. Group V, p < 0.001 vs. Group N), 0.197 +/- 0.012 in Group V (p = 0.031 vs. Group N), and 0.245 +/- 0.021 in Group N. Serum HGF concentrations in the AA were 0.282 +/- 0.014 in Group E (p = 0.045 vs. Group V, p = 0.021 vs. Group N), 0.246 +/- 0.012 in Group V, and 0.237 +/- 0.009 in Group N. Serum HGF extraction in the heart (HGF in the AA-HGF in the CS) in Group E (0.170 +/- 0.018) was significantly higher compared with in Group V (0.049 +/- 0.011) or Group N (0.008 +/- 0.005). There was a significant negative correlation between the severity of coronary arteriosclerosis and serum HGF concentration in CS (r = -0.66, p < 0.001), and a significant positive correlation between the severity of coronary arteriosclerosis and HGF extraction in the heart (r = 0.75. p < 0.001).

CONCLUSIONS

We conclude that the difference of HGF levels between CS and AA in patients with CAD are decreased, and extent of decreases in HGF levels correlates with the severity of coronary arteriosclerosis. The abnormality of HGF metabolism in the heart may contribute to the progression of coronary arteriosclerosis.

[Usefulness of washout rate analysis in adenosine triphosphate-stress thallium-201 myocardial scintigraphy in patients with vasospastic angina]

OBJECTIVES

This study evaluated the usefulness of washout rate analysis in adenosine triphosphate(ATP) stress thallium-201 scintigraphy for the diagnosis of vasospastic angina.

METHODS

This study included 76 patients with vasospastic angina and 18 normal controls undergoing coronary arteriography. If significant coronary artery stenosis (> or = 50%) was pointed out, the subject was excluded from this study. 111 MBq of thallium-201 was intravenously injected 3 min after ATP loading (0.16 mg/kg/min) was started. Single photon emission computed tomography (SPECT) was performed 10 min and 4 hr after intravenous injection of ATP. The mean washout rate (%) was calculated based on a bull's eye map and was divided into 3 regions, the antero-septal/lateral/inferior regions. The washout rate in each region was calculated. Regional uptake was visually estimated based on the 17 segments of SPECT images.

RESULTS

The washout rate in the normal control group was 48.9 +/- 4.1 (mean +/- SD)%. In patients with vasospastic angina, the washout rate in areas with coronary vasospasm was 33.4 +/- 5.5%. This value was significantly lower than in the areas without coronary vasospasm (42.8 +/- 3.6%). The usefulness of washout rate analysis in the diagnosis of vasospastic angina with a cut-off value of less than -2SD from normal washout rate in the 3 regions was examined. A significantly higher diagnostic value was found by washout rate analysis (sensitivity 72.3%, specificity 79.7%, and accuracy 74.6%) compared with visual evaluation of early images (sensitivity 50.3%, specificity 73.9%, and accuracy 57.5%).

CONCLUSIONS

The diagnostic value of washout rate analysis was significantly higher (73.1%) compared with visual evaluation of early images (50.3%) in patients with multivessel vasospastic angina.

The influence of left ventricular geometry on coronary vasomotion in patients with essential hypertension

The objective of this study was to assess the influence of left ventricular (LV) geometric pattern on coronary vasomotion in patients with essential hypertension. We studied 34 hypertensive patients, who had never been treated, with angiographically normal coronary arteries. Patients were classified into four LV geometric patterns by echocardiography: normal, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. The responses of coronary vasomotion in left anterior descending artery to vasoactive agents (acetylcholine, isosorbide dinitrate, adenosine triphosphate) were examined using a Doppler guidewire and quantitative coronary angiography. The percent increase in coronary blood flow evoked with acetylcholine (endothelium-dependent vasomotion) showed lowest in concentric hypertrophy, followed by eccentric hypertrophy, concentric remodeling, and normal geometry. The significant linear relationship between acetylcholine-induced coronary blood flow and LV mass was noted. There was no difference in the percent increase in coronary blood flow evoked with isosorbide dinitrate (endothelium-independent vasomotion of conduit vessel) among the four groups. The percent increase in coronary blood flow evoked with adenosine triphosphate (endothelium-independent vasomotion of resistant vessel) was significantly lower in patients with concentric hypertrophy than in the other three groups. The results in this study suggest that coronary vasomotion may be associated with LV geometry in patients with hypertension. The endothelium-dependent vasodilation is impaired progressively as LV hypertrophy advances. The endothelium-independent vasodilation of microvessels is impaired only in concentric hypertrophy. This advanced abnormality of coronary vasomotion may contribute to the high cardiovascular morbidity and mortality in patients with concentric hypertrophy.

Antiphospholipid syndrome with acute myocardial infarction and portal vein occlusion: a case report

A 62-year-old woman was admitted to hospital because of chest oppression and abdominal discomfort. Coronary arteriography revealed that the proximal left anterior descending artery had a large thrombus with TIMI (Thrombolysis in Myocardial Infarction) Grade 3 flow. On the second hospital day, she had sudden hematemesis because of esophageal varices. Her general condition became stable with conventional therapy. On the 20th hospital day, coronary arteriography and arterial portography showed that the thrombus had diminished. Arterial portography also revealed total occlusion of the portal vein as well as giant gastric varices. She was diagnosed as antiphospholipid syndrome, based on the presence of lupus anticoagulant. The treatment of this case was very complicated because of the bleeding from the esophageal varices induced by the anticoagulant therapy for the thrombus. Prednisolone was administered for 1 month, but no remarkable effects were observed. Therefore, she was treated with endoscopic sclerotherapy for the esophageal varices and anticoagulant therapy for prevention of thrombosis.

Relationship between insulin resistance and cardiac sympathetic nervous function in essential hypertension

BACKGROUND

It has been suggested that hyperinsulinemia and insulin resistance participate in the pathogenesis of hypertension, in part by activating sympathetic activity.

OBJECTIVE

We aimed to examine the relationship between insulin resistance and cardiac sympathetic nervous function in patients with essential hypertension using 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy.

METHODS AND RESULTS

Twenty-eight patients (18 men) with essential hypertension and 11 (seven men) control individuals with a mean age of 55.8+/-3.3 years were recruited. Patients with diabetes mellitus, congestive heart failure or coronary artery disease were excluded from this study. To evaluate insulin resistance, we used steady-state plasma glucose (SSPG; mg/dl) levels measured by the SSPG method. To evaluate cardiac sympathetic nervous function, we calculated the heart-to-mediastinum ratio from the delayed MIBG image (H:M-D) and the mean washout rate (WOR, %). There were significant differences (P<0.01) in SSPG, H:M-D and WOR between the essential hypertension and control individual groups (125 versus 103 mg/dl, 2.2 versus 2.4, and 32 versus 23%, respectively). Stepwise regression analysis showed that SSPG and plasma norepinephrine level are independent predictors for the cardiac sympathetic nervous function obtained from MIBG scintigraphy.

CONCLUSIONS

These findings indicate that insulin resistance is significantly related to activation of the cardiac sympathetic nervous function associated with left ventricular hypertrophy in patients with essential hypertension.

Effect of insulin resistance on left ventricular hypertrophy and dysfunction in essential hypertension

BACKGROUND

In hypertensive patients, the relationships between glucose tolerance and left ventricular hypertrophy (LVH) and left ventricular diastolic function (LVDF) have been described in several reports.

OBJECTIVE

In this study, we examined the relationships between insulin resistance and LVH and LVDF in hypertensive patients from the therapeutic perspective.

METHODS AND RESULTS

The study participants were essential hypertensive patients with impaired glucose tolerance (IGT-HT, n = 26), hypertensive patients with normal glucose tolerance (NGT-HT, n = 39), and normotensive control individuals (n = 18). Insulin resistance was evaluated by the insulin suppression test by use of the steady-state plasma glucose (SSPG) level. Left ventricular mass index (LVMI) and LVDF, which was determined by the E:A ratio, were estimated by echocardiography. Temocapril, an angiotensin-converting enzyme inhibitor, was administered in an open, non-randomized manner with a mean dose of 2.8+/-0.2 mg/ day, and the mean administration period was 18 weeks. The systolic and diastolic blood pressure, the LVMI, and the SSPG level were significantly higher in the hypertensive patients than in the control individuals. The mean systolic and diastolic blood pressures were significantly decreased by treatment with Temocapril. Before treatment, stepwise regression analysis showed that SSPG is an independent predictor for LVMI and LVDF. After treatment, the changes in LVMI (D-LVMI; %) (-15.1+/-1.5), the changes in LVDF (D-E:A; %) (-38.2+/-4.1), and the changes in insulin resistance (D-SSPG; %) (-13.7+/-1.7) were significantly higher in the IGT-HT group than in the NGT-HT group (-11.4+/-1.1, -18.1+/-1.7, -9.4+/-1.4, respectively), and the D-SSPG was an independent predictor for D-LVMI and D-E :A.

CONCLUSIONS

The results of this study indicate that insulin resistance is an important factor affecting LVH and LVDF.

[Markedly decreased uptake with 123I-MIBG myocardial scintigraphy in a case with vasospastic angina]

A 68-year-old female whose myocardial sympathetic function was severely damaged with multi-vessel vasospastic angina is presented. She had no signs of autonomic dysfunction or diabetes mellitus. Myocardial imaging with 123I-MIBG showed extremely diminished uptake, but 201TlCl and 123I-BMIPP SPECT images were almost normal. Coronary arteriography revealed no significant atherosclerotic stenosis, multivessel spasm was observed by provocation test using acetylcholine. The extremely diminished uptake of 123I-MIBG was slightly increased in response to medication and the subsequent improvement of the patient's condition. Markedly decreased uptake with 123I-MIBG myocardial scintigraphy was considered to be due to multi-vessel spastic angina. We believe that this method of imaging study is useful for evaluating the healing stage of myocardial sympathetic dysfunction.

Effects of probucol and cilostazol alone and in combination on frequency of poststenting restenosis

The present study was conducted to assess the preventive effect of combined treatment with probucol, an antioxidant, and cilostazol, a phosphodiesterase inhibitor, against poststenting restenosis. Study patients were randomized to 4 modality groups 1 week before stenting: control, probucol (500 mg/day), cilostazol (200 mg/day), and probucol plus cilostazol. Treatment on these modalities was conducted from 5 prestent days until the poststenting follow-up evaluation (6 poststenting months). All patients received aspirin (81 mg/day). The efficacy of each modality against restenosis was evaluated in a total 126 patients with 165 coronary arterial lesions, using a quantitative method. The decrease in luminal diameter at the poststenting follow-up was 1.04 +/- 0.57 mm for controls, 0.88 +/- 0.82 mm for those taking probucol, 0.61 +/- 0.59 mm for those taking cilostazol (p <0.05 vs control), and 0.40 +/- 0.52 mm (p <0.01 vs control) for the combined treatment group. Restenosis rate per segment was 31.7% for controls, 16.7% for the probucol group, 12.5% for the cilostazol group (p <0.05 vs control), and 9.5% for the combined treatment group (p <0.05 vs the control). Neither mortality, myocardial infarction, stent thrombosis, or coronary bypass surgery, nor any serious complications were observed in the combined treatment group. Combined treatment with probucol and cilostazol has thus proved safe and effective in preventing acute poststenting complications and suppressing chronic restenosis.

[Usefulness of 123I-BMIPP myocardial scintigraphy for evaluation of the left ventricular function in patients with chronic heart failure]

We examined the relationship between free fatty acid metabolism using 123I beta-methyl-iodophenyl-pentadecanoic acid (BMIPP) and cardiac function in patients with chronic heart failure (CHF). Cardiac free fatty acid metabolism was evaluated by the heart to mediastinum ratio (H/M), the heart to lung ratio (H/Lu), the heart to liver ratio (H/Li) and the myocardial uptake ratio (MUR) obtained from the planar imaging. Cardiac function was evaluated by the percent of fractional shortening (%FS) and the amount of left ventricular mass (LV mass) calculated with echocardiography. The study included 34 male and 14 female subjects of CHF with mean age of 61 +/- 9 years; dilated cardiomyopathy (DCM): n = 17, ischemic heart disease (IHD): n = 16, valvular disease: n = 5, hypertrophic cardiomyopathy: n = 4, hypertension: n = 4, amyloidosis: n = 2. The correlations between indices of BMIPP uptake and those of echocardiography were as follows: H/M vs. %FS (r = 0.67, p < 0.01), H/Lu vs. %FS (r = 0.49, p < 0.01), H/Li vs. %FS (r = 0.12, p = 0.42), MUR vs. %FS (r = 0.03, p = 0.86) and MUR/LV mass vs. %FS (r = 0.59, p < 0.01). The correlation coefficient between H/M and MUR/LV mass in patients with IHD was higher than that in patients with DCM. In conclusion, BMIPP, in particular, is a useful tool for evaluating cardiac function in patients with CHF.

[Hydraulic conductivity of the visceral pleura with hemodynamic lung edema in dogs]

Hydraulic conductivity of the visceral pleura was measured in situ in anesthetized dogs. There were two groups: control (n = 7), and edema (n = 5). The 7th intercostal space of the left thorax was opened. In each group, a hemispherical capsule, filled with physiological salt solution, was attached to the visceral pleura of left lobe by negative pressure made with a vacuum pump. In the edema group, pulmonary venous pressure was increased by ligation of the pulmonary vein. The transpleural fluid flow (V) was measured at different intracapsular pressures (delta P). The hydraulic conductivity was calculated from the relation between the fluid flow rate (v) and the intracapsular pressure, i.e., the slope of the linear regression line. The hydraulic conductivities in the control and edema groups were 1.49 +/- 0.68 and 3.19 +/- 1.13 nL.min-1.cmH2O-1.cm-2, respectively. We conclude that the pleural tissue may play an important role in hydraulic conductivity of the visceral pleura when pulmonary venous pressure is high.

Gallium-67 citrate scintigraphy in idiopathic pericarditis--report of a case

We report a case of idiopathic pericarditis in a 71-year-old woman without a friction rub or electrocardiographic changes suggestive of pericardial inflammation. She noticed dyspnea and palpitation on exertion about 40 days before admission. After admission, pericardial effusion and inflammatory reactions, such as elevated C-reactive protein, were found. Moreover, gallium-67 citrate scintigraphy revealed abnormal isotope accumulation over the cardiac silhouette. Therefore, she was diagnosed as having "active" pericarditis. The finding with the gallium scan became negative with steroid therapy. In this case, a gallium scan was very useful in assessing and monitoring the course of pericardial inflammation.

[Hydraulic conductivity of visceral pleura in dogs]

We measured the hydraulic conductivity of the visceral pleura in seven mongrel dogs in situ. The left chest was opened at the seventh intercostal space. A hemispherical capsule, filled with physiological saline, was attached to the visceral pleura of the left lower lobe by the negative pressure in the plate, using a vacuum pump. Transpleural fluid flow (V) was measured at different intracapsular pressures (delta P). The hydraulic conductivity was calculated from the relation between fluid flow and intracapsular pressure, i.e., the slope of the linear regression line. The hydraulic conductivity was 1.49 +/- 0.68 (mean +/- SD) nL.min-1 x cmH2O-2. Our values were smaller than those of former reports obtained in vivo. It is suggested that the dynamics mechanisms of plural effusion may be clarified by studies using our method.

[A case of anomalous course of the pulmonary vein with a tracheobronchus]

A 28-year-old man was admitted to our hospital for further evaluation of a loop-like abnormal shadow in the middle lower lung field on chest X-ray film. Pulmonary angiograms demonstrated staining of the abnormal shadow during the venous phase. The abnormal vein descended from the right upper lobe to the middle lobe and then tortuously made a loop upward to drain into the left atrium. A part of the right apical vein was stenosed. The right apical segmental bronchus directly branched from the trachea. These observations indicate that the abnormalities may have originated in the prenatal period. Cases of anomalous course of the pulmonary vein are very rare.

Increased proportions of peripheral blood gamma delta T cells in patients with pulmonary tuberculosis

There is a small population of peripheral T cells bearing the gamma delta T-cell receptor, which may be involved in the defense against invading microorganisms and tumor cells. The present study was designed to evaluate the levels of gamma delta T cells in patients with pulmonary tuberculosis, bacterial pneumonia, chronic lower respiratory tract infection, lung cancer, and normal control subjects with or without old tuberculous lesion. The results showed that only patients with tuberculosis had significantly increased proportions of peripheral blood gamma delta T cells. This study suggests that the increased proportions of gamma delta T cells in tuberculosis could be related to T-cell activation by Mycobacterium tuberculosis, although it remains to be investigated which components of mycobacteria are the major ligands for gamma delta T cells.