Background— Adiponectin is an adipocyte-derived plasma protein that accumulates in the injured artery and has potential antiatherogenic properties. This study was designed to determine whether a decreased plasma adiponectin level (hypoadiponectinemia) can be independently associated with the prevalence of coronary artery disease (CAD).
Methods and Results— The consecutive 225 male patients were enrolled from inpatients who underwent coronary angiography. Voluntary blood donors (n=225) matched for age served as controls. Plasma adiponectin levels in the CAD patients were significantly lower than those in the control subjects. Multiple logistic regression analysis including plasma adiponectin level, diabetes mellitus, dyslipidemia, hypertension, smoking habits, and body mass index revealed that hypoadiponectinemia was significantly and independently correlated with CAD (P<0.0088). The entire study population was categorized in quartiles based on the distribution of plasma adiponectin levels. The interquartile cutoff points were 4.0, 5.5, and 7.0 µg/mL. The multivariate-adjusted odds ratios for CAD in the first, second, and third quartiles were 2.051 (95% confidence interval [CI], 1.288 to 4.951), 1.221 (95% CI, 0.684 to2.186), and 0.749 (95%CI, 0.392 to 1.418), respectively.
Conclusions— Male patients with hypoadiponectinemia (<4.0 µg/mL) had a significant 2-fold increase in CAD prevalence, independent of well-known CAD risk factors.
Key Words: adiponectin • risk factor • coronary artery disease
Obesity, defined as excess fat accumulation, is the most common
cause of cardiovascular morbidity and mortality in industrialized
countries.
1–3 Excess body fat, in particular, abdominal
visceral fat accumulation, is frequently accompanied by diabetes
mellitus, dyslipidemia, and hypertension and finally results
in atherosclerotic vascular diseases.
1,3 Adipose tissue secretes
various bioactive molecules that may directly contribute to
the development of obesity-related diseases.
4–7 These
results suggest that the dysregulation of adipocyte-derived
endocrine factors caused by overnutrition may directly participate
in the development of atherosclerosis. Adiponectin is an adipose-derived
factor, which we identified in the human adipose tissue cDNA
library.
8 Plasma adiponectin rapidly accumulates in the subendothelial
space of the injured human artery. We have reported that physiological
concentrations of human recombinant adiponectin inhibited monocyte
adhesion to endothelial cells and macrophage-to–foam cell
transformation, as well as tumor necrosis factor- secretion
from macrophages in vitro.
9–12 Recently, we found that
adiponectin acts as a platelet-derived growth factor-BB–binding
protein and generally inhibits growth factor–induced proliferation
and migration of vascular smooth muscle cells.
13
Clinically, hypoadiponectinemia has been observed in patients with obesity, diabetes mellitus, and coronary artery disease (CAD), and plasma adiponectin levels increase during weight reduction.9,14–17 These findings indicate that adiponectin acts as an endogenous antiatherogenic factor regulated by personal lifestyle. Therefore, understanding the clinical significance of plasma adiponectin may be helpful in preventing the development of atherosclerotic vascular diseases. Although we already reported that the plasma adiponectin level was low in patients with CAD, the clinical importance of hypoadiponectinemia in CAD has not been fully elucidated.9 In the present study, we measured plasma adiponectin levels in consecutive CAD patients drawn from a larger population and investigated whether hypoadiponectinemia is significantly associated with CAD prevalence after adjustment for well-known CAD risk factors.
Study GroupConsecutive male patients were enrolled from inpatients who
underwent coronary angiography at Osaka University Hospital
or affiliated hospitals between November 2000 and September
2001. Cases included patients aged 40 to 69 years who had a
75% or greater organic stenosis of at least 1 major coronary
artery as confirmed by coronary angiogram, who had developed
a myocardial infarction, or who had previously undergone percutaneous
transluminal coronary angioplasty or coronary artery bypass
graft surgery. The control subjects were selected from men who
visited our affiliated hospitals or clinics for a physical checkup.
Controls were characterized by no history of angina and other
heart disease, a normal resting ECG, and normal exercise ECG
stress testing. They were matched with CAD patients for age.
Patients with renal dysfunction and those taking synthetic peroxisome
proliferator-activated receptor (PPAR)- ligands were excluded.
18,19 All patients and subjects enrolled in this study were Japanese
and given written, informed consent. This study was approved
by the Ethics Committee of Osaka University.
Laboratory Methods
Venous blood was drawn from all patients and control subjects after an overnight fast. Plasma samples were kept at -80°C for subsequent assay. The plasma concentration of adiponectin was evaluated by a sandwich ELISA system (adiponectin ELISA kit, Otsuka Pharmaceutical Co Ltd) as previously reported.14 Serum total cholesterol and triglyceride concentrations were determined by an enzymatic method. HDL cholesterol was also measured by an enzymatic method after heparin and calcium precipitation. Plasma glucose was measured by a glucose oxidase method. Body mass index (BMI) was calculated as weight divided by the square of height. Risk factors were defined as follows. Diabetes mellitus was defined according to World Health Organization criteria.20 Dyslipidemia was defined as a total cholesterol concentration >5.69 mmol/L, a triglyceride concentration >1.69 mmol/L, an HDL cholesterol concentration <1.03 mmol/L, and/or having received treatment for dyslipidemia. Hypertension was defined as systolic blood pressure >140 mm Hg, diastolic blood pressure >90 mm Hg, or having received treatment for hypertension. Smoking was defined as current smoker.
Statistical Methods
For continuous variables, results are presented as mean±SD or median (minimum, maximum), and the differences between the 2 groups were evaluated with an unpaired t test or the Mann-Whitney U test. Categorical variables are presented by frequency counts, and intergroup comparisons were analyzed by a 2 test. Data that did not demonstrate a gaussian distribution were logarithmically transformed. The CAD patients and control subjects were categorized in quartiles based on the plasma adiponectin level. The interquartile cutoff points of plasma adiponectin level were 4.0, 5.5, and 7.0 µg/mL: category 1, <4.0 µg/mL; 4.0 µg/mLcategory 2 <5.5 µg/mL; 5.5 µg/mLcategory 3 <7.0 µg/mL; and category 4, 7.0 µg/mL. Associations between CAD and all other parameters were first analyzed by simple logistic regression analysis and then by multivariate analysis. Variables included in the analysis were plasma adiponectin level (quantitative), diabetes mellitus (yes or no), dyslipidemia (yes or no), hypertension (yes or no), smoking habit (yes or no), and BMI (quantitative). The multivariate-adjusted odds ratios (ORs) are presented with 95% confidence intervals (CIs). All calculations were performed by using a standard statistical package (JMP for Macintosh, version 4.0).
Patient Characteristics.The clinical characteristics of male CAD patients and control
subjects are shown in Plasma adiponectin levels in
the CAD patients were significantly lower than those in control
subjects (
P<0.0001). The median (minimum, maximum) level
was 4.7 (0.7, 15.9) in the CAD patients and 5.9 (1.6, 15.2)
in control subjects. The number of subjects according to logarithmically
transformed adiponectin levels in CAD and control are shown
in In the first quartile (plasma adiponectin level
<4.0 µg/mL), the number of CAD patients was 3 times
that of control subjects, but in the fourth quartile (plasma
adiponectin level 7.0 µg/mL), the number of CAD patients
was less than that of control subjects. The CAD patients had
significantly higher levels of BMI, fasting plasma glucose,
triglycerides, LDL cholesterol, and systolic blood pressure
and lower levels of HDL cholesterol. There were no significant
differences in age, total cholesterol, diastolic blood pressure,
and the number of smokers between the 2 groups.
fig.ommitted |
Clinical Characteristics of Control Subjects and CAD Patients | |
fig.ommitted |
The number of subjects according to log adiponectin levels in patients with CAD (solid bars) and control subjects (open bars). Logarithmic transformation of the plasma adiponectin concentrations was performed as needed to improve normality.
| |
Adiponectin and CAD
The results of logistic regression analysis are shown in To evaluate each factor in simple logistic regression analysis was performed. There were significant differences between the 2 groups in terms of BMI, plasma adiponectin level, triglyceride, HDL cholesterol, LDL cholesterol, fasting plasma glucose, systolic blood pressure, diabetes mellitus, dyslipidemia, hypertension, and smoking habit. However, triglycerides, HDL cholesterol, LDL cholesterol, and dyslipidemia were dependent on each other. Systolic blood pressure and hypertension as well as fasting plasma glucose and diabetes mellitus were also dependent on each other. Among these parameters, dyslipidemia, hypertension, and diabetes mellitus were selected as the representative factors from their higher correlation with CAD. For multiple logistic regression analysis, all parameters were clustered into 5 groups (dyslipidemia, diabetes mellitus, hypertension, smoking habit, and BMI). Multiple logistic regression analysis with plasma adiponectin level, dyslipidemia, diabetes mellitus, hypertension, smoking habit, and BMI revealed that hypoadiponectinemia was independently correlated with CAD (P<0.0088) as well as known CAD risk factors.
fig.ommitted |
Logistic Regression Analysis | |
Cutoff Point of Hypoadiponectinemia
The multivariate-adjusted ORs for CAD in each of the quartiles based on the plasma adiponectin level are shown in. For clinical translation, cut off points were selected, although a dose-response relation was statistically observed between the probability of CAD (p(CAD)) and plasma adiponectin level: -log p(CAD)/[1-p(CAD)]=-2.1963+[3.0410xlog(plasma adiponectin level)], Wald’s 2 test, P<0.001, R2=0.0557 (n=450). The cutoff points were 4.0, 5.5, and 7.0 µg/mL plasma adiponectin. This model was adjusted for other known risk factors. ORs for CAD in the first, second, and third quartiles were 2.051 (95%CI, 1.288 to 4.951), 1.221 (95%CI, 0.684 to2.186), and 0.749 (95%CI, 0.392 to 1.418) compared with the fourth quartile.
fig.ommitted |
ORs for CAD in the first, second, and third quartiles compared with the fourth quartile. This model was adjusted for other known risk factors. Vertical bars indicate 95% CI.
| |
In the present study, hypoadiponectinemia was found to be highly
associated with CAD prevalence after adjustment for well-known
CAD risk factors such as diabetes mellitus, dyslipidemia, hypertension,
smoking habit, and BMI in male subjects. For translation into
the clinical setting, it is very important to determine the
abnormal range of plasma adiponectin concentrations. The multivariate-adjusted
OR for CAD revealed that male patients with hypoadiponectinemia
(<4.0 µg/mL) had a 2-fold increase in CAD prevalence,
independent of well-known CAD risk factors. We previously reported
that the plasma adiponectin level in female CAD patients was
also significantly lower than that in age- and BMI-adjusted
healthy female control subjects.
9 However, the plasma adiponectin
levels in female subjects were significantly higher than those
in male subjects. Our recent findings suggest that androgen-induced
hypoadiponectinemia is related to the high risk of atherosclerosis
in men.
21 Because male sex is an important risk factor for CAD,
we focused on middle-aged men in the current study. Further
study will be necessary to elucidate the cutoff point of hypoadiponectinemia
in women with regard to CAD prevalence.
Adiponectin and Insulin Resistance in CAD
In addition to CAD, we previously reported that the plasma adiponectin level was decreased in obesity and type 2 diabetes.9,14–17 However, multiple logistic regression analysis revealed that hypoadiponectinemia is significantly associated with CAD prevalence, even after adjustment for BMI and diabetes mellitus. Recently, we and others have reported that adiponectin itself may affect glucose metabolism in mice.22–24 Therefore, hypoadiponectinemia may be relevant to the states of insulin resistance in men. In this study, however, hypoadiponectinemia in the CAD patients was observed even when the presence or absence of diabetes mellitus was adjusted for. Interestingly, the plasma adiponectin concentrations in diabetic patients with macroangiopathy were significantly lower than those of diabetic patients without macroangiopathy.16 Therefore, hypoadiponectinemia may have an adverse effect on the development of diabetic macroangiopathy.
Adiponectin as a Protective Factor in CAD
Adiponectin is an adipocyte-specific plasma protein, which is abundantly present in the human blood stream.14 We have previously reported that adiponectin acts as a modulator of the inflammatory response in the vascular wall. Plasma adiponectin rapidly accumulates in the subendothelial space of the injured human artery, and recombinant adiponectin was found to have inhibited monocyte adhesion to endothelial cells and the macrophage-to–foam cell transformation, as well as vascular smooth muscle cell proliferation, in vitro.9–13 Because these steps are believed to be crucial in the development of atherosclerosis, adiponectin can be considered an endogenous biologically relevant modulator of vascular remodeling, and hypoadiponectinemia may cause an excessive inflammatory response in the coronary artery. Recently, we investigated whether plasma adiponectin levels were an inverse predictor of cardiovascular outcomes among patients with end-stage renal disease.19 Therefore, hypoadiponectinemia can be considered a candidate risk factor for CAD, although a large-scale prospective study in the general population is necessary.
In summary, hypoadiponectinemia (<4.0 µg/mL) was found
to be independently associated with the presence of CAD after
adjustment for other well-known CAD risk factors in men. Our
findings suggest that the adipocyte-specific plasma protein
adiponectin is one of the clinically important molecules associated
with atherosclerosis and that measurement of plasma adiponectin
level will be helpful to evaluate CAD risk.
This work was supported by grants from the Japanese Ministry
of Education, the Japan Society for Promotion of Science-Research
for the Future Program, the Takeda Medical Research Foundation,
and the Fuji Foundation for Protein Research. Other members
of the Osaka CAD Study Group include Bunichiro Kishino and Yoshiyuki
Nagai (Rinku General Medical Center); Katsunori Ishikawa and
Kengo Matsumoto (National Hospital Kure Medical Center); Shingo
Yoshida and Mitsukazu Yamane (Kawasaki Hospital); Koji Yanagi
and Miwa Ryo (Osaka Central Hospital); Masakazu Menjyu (Mino
Municipal Hospital); and Koji Yoshino (Toyonaka Municipal Hospital).
We gratefully acknowledge the technical assistance of Sachiyo
Tanaka, Yuko Matsukawa, Atsuko Ohya, Chiaki Ikegami, and Yuri
Fujita.
Received August 9, 2002; accepted November 11, 2002.
- Matsuzawa Y, Nakamura T, Shimomura I, Kotani K. Visceral fat accumulation and cardiovascular disease. Obes Res. 1995; 3 (suppl 5): 645S–647S.
- Nielsen S, Jensen NS. Obesity and cardiovascular disease: is body structure a factor? Curr Opin Lipidol. 1997; 8: 200–204.
- Nakamura T, Tokunaga K, Shimomura I, Nishida M, Yoshida S, Kotani K, Islam AH, Keno Y, Kobatake T, Nagai Y, Fujioka S, Tarui S, Matsuzawa Y. Contribution of visceral fat accumulation to the development of coronary artery disease in non-obese men. Atherosclerosis. 1994; 107: 239–246.
- Spiegelman BM, Choy L, Hotamisligil GS, Graves RA, Tontonoz P. Regulation of adipocyte gene expression in differentiation and syndromes of obesity/diabetes. J Biol Chem. 1993; 268: 6823–6826.
- Zhang Y, Proenca R, Maffei M, Barone M, Leopold L, Friedman JM. Positional cloning of the mouse obese gene and its human homologue. Nature. 1994; 372: 425–432.
- Hotamisligil GS, Shargill NS, Spiegelman BM. Adipose expression of tumor necrosis factor-: direct role in obesity-linked insulin resistance. Science. 1993; 259: 87–91.
- Shimomura I, Funahashi T, Takahashi M, Maeda K, Kotani K, Nakamura T, Yamashita S, Miura M, Fukuda Y, Takemura K, Tokunaga K, Matsuzawa Y. Enhanced expression of PAI-1 in visceral fat: possible contributor to vascular disease in obesity. Nat Med. 1996; 2: 800–803.
- Maeda K, Okubo K, Shimomura I, Funahashi T, Matsuzawa Y, Matsubara K. cDNA cloning and expression of a novel adipose specific collagen-like factor, apM1 (AdiPose Most abundant Gene transcript 1). Biochem Biophys Res Commun. 1996; 221: 286–289.
- Ouchi N, Kihara S, Arita Y, Maeda K, Kuriyama H, Okamoto Y, Hotta K, Nishida M, Takahashi M, Nakamura T, Yamashita S, Funahashi T, Matsuzawa Y. Novel modulator for endothelial adhesion molecules; adipocyte-derived plasma protein adiponectin. Circulation. 1999; 100: 2473–2476.
- Ouchi N, Kihara S, Arita Y, Okamoto Y, Maeda K, Kuriyama H, Hotta K, Nishida M, Takahashi M, Muraguchi M, Ohmoto Y, Nakamura T, Yamashita S, Funahashi T, Matsuzawa Y. Adiponectin, an adipocyte-derived plasma protein, inhibits endothelial NF-B signaling through a cAMP-dependent pathway. Circulation. 2000; 102: 1296–1301.
- Ouchi N, Kihara S, Arita Y, Nishida M, Matsuyama A, Okamoto Y, Ishigami M, Kuriyama H, Kishida K, Nishizawa H, Hotta K, Muraguchi M, Ohmoto Y, Yamashita S, Funahashi T, Matsuzawa Y. Adipocyte-derived plasma protein, adiponectin, suppresses lipid accumulation and class A scavenger receptor expression in human monocyte-derived macrophages. Circulation. 2001; 103: 1057–1063.
- Okamoto Y, Arita Y, Nishida M, Muraguchi M, Ouchi N, Takahashi M, Igura T, Inui Y, Kihara S, Nakamura T, Yamashita S, Miyagawa J, Funahashi T, Matsuzawa Y. An adipocyte-derived plasma protein, adiponectin, adheres to injured vascular walls. Horm Metab Res. 2000; 32: 47–50.
- Arita Y, Kihara S, Ouchi N, Maeda K, Kuriyama H, Okamoto Y, Kumada M, Hotta K, Nishida M, Takahashi M, Nakamura T, Shimomura I, Muraguchi M, Ohmoto Y, Funahashi T, Matsuzawa Y. Adipocyte-derived plasma protein adiponectin acts as a platelet-derived growth factor-BB-binding protein and regulates growth factor-induced common postreceptor signal in vascular smooth muscle cell. Circulation. 2002; 105: 2893–2898.
- Arita Y, Kihara S, Ouchi N, Takahashi M, Maeda K, Miyagawa J, Hotta K, Shimomura I, Nakamura T, Miyaoka K, Kuriyama H, Nishida M, Yamashita S, Okubo K, Matsubara K, Muraguchi M, Ohmoto Y, Funahashi T, Matsuzawa Y. Paradoxical decrease of an adipose-specific protein, adiponectin, in obesity. Biochem Biophys Res Commun. 1999; 257: 79–83.
- Yang WS, Lee WJ, Funahashi T, Tanaka S, Matsuzawa Y, Chao CL, Chen CL, Tai TY, Chuang LM. Weight reduction increases plasma levels of an adipose-derived anti-inflammatory protein, adiponectin. J Clin Endocrinol Metab. 2001; 86: 3815–3819.
- Hotta K, Funahashi T, Arita Y, Takahashi M, Matsuda M, Okamoto Y, Iwahashi H, Kuriyama H, Ouchi N, Maeda K, Nishida M, Kihara S, Sakai N, Nakajima T, Hasegawa K, Muraguchi M, Ohmoto Y, Nakamura T, Yamashita S, Hanafusa T, Matsuzawa Y. Plasma concentrations of a novel, adipose-specific protein, adiponectin, in type 2 diabetic patients. Arterioscler Thromb Vasc Biol. 2000; 20: 1595–1599.
- Hotta K, Funahashi T, Bodkin NL, Ortmeyer HK, Arita Y, Hansen BC, Matsuzawa Y. Circulating concentrations of the adipocyte protein adiponectin are decreased in parallel with reduced insulin sensitivity during the progression to type 2 diabetes in rhesus monkeys. Diabetes. 2001; 50: 1126–1133.
- Maeda N, Takahashi M, Funahashi T, Kihara S, Nishizawa H, Kishida K, Nagaretani H, Matsuda M, Komuro R, Ouchi N, Kuriyama H, Hotta K, Nakamura T, Shimomura I, Matsuzawa Y. PPAR- ligands increase expression and plasma concentrations of adiponectin, an adipose-derived protein. Diabetes. 2001; 50: 2094–2099.
- Zoccali C, Mallamaci F, Tripepi G, Benedetto FA, Cutrupi S, Parlongo S, Malatino LS, Bonanno G, Seminara G, Rapisarda F, Fatuzzo P, Buemi M, Nicocia G, Tanaka S, Ouchi N, Kihara S, Funahashi T, Matsuzawa Y. Adiponectin, metabolic risk factors, and cardiovascular events among patients with end-stage renal disease. J Am Soc Nephrol. 2002; 13: 134–141.
- The Expert Committee. Report of the Expert Committee on the diagnosis and classification of diabetes mellitus. Diabetes Care. 1997; 20: 1183–1197.
- Nishizawa H, Shimomura I, Kishida K, Maeda N, Kuriyama H, Nagaretani H, Matsuda M, Kondo H, Furuyama N, Kihara S, Nakamura N, Tochino Y, Funahashi T, Matsuzawa Y. Androgens decrease plasma adiponectin, an insulin-sensitizing adipocyte-derived protein. Diabetes. 2002; 51: 2734–2741.
- Yamauchi T, Kamon J, Waki H, Terauchi Y, Kubota N, Hara K, Mori Y, Ide T, Murakami K, Tsuboyama-Kasaoka N, Ezaki O, Akanuma Y, Gavrilova O, Vinson C, Reitman ML, Kagechika H, Shudo K, Yoda M, Nakano Y, Tobe K, Nagai R, Kimura S, Tomita M, Froguel P, Kadowaki T. The fat-derived hormone adiponectin reverses insulin resistance associated with both lipoatrophy and obesity. Nat Med. 2001; 7: 941–946.
- Weyer C, Funahashi T, Tanaka S, Hotta K, Matsuzawa Y, Pratley RE, Tataranni PA. Hypoadiponectinemia in obesity and type 2 diabetes: close association with insulin resistance and hyperinsulinemia. J Clin Endocrinol Metab. 2001; 86: 1930–1935.
- Maeda N, Shimomura I, Kishida K, Nishizawa H, Matsuda M, Nagaretani H, Furuyama N, Kondo H, Takahashi M, Arita Y, Komuro R, Ouchi N, Kihara S, Tochino Y, Okutomi K, Horie M, Takeda S, Aoyama T, Funahashi T, Matsuzawa Y. Diet-induced insulin resistance in mice lacking adiponectin/ACRP30. Nat Med. 2002; 8: 731–737.
作者:
Masahiro Kumada Shinji Kihara Satoru Sumitsuji 2007-5-18