Relationship between serum adiponectin levels and age in healthy subjects and patients with type 2 diabetes.

OBJECTIVE: Serum adiponectin levels are affected by gender, body fat mass, several pathological factors or therapeutic interventions and it might be also affected by age. This study aimed to investigate the relationship between serum adiponectin levels and age in several physiological states. DESIGN, PATIENTS AND MEASUREMENTS: The study was carried out in 21 100 healthy subjects (12 363 men and 8737 women) and 1833 patients with type 2 diabetes (1233 men and 600 women). Physical and demographic characteristics were recorded, and blood samples were collected to measure serum adiponectin levels. Using these data, we determined the relationships between serum adiponectin levels and various parameters, including age. RESULTS: Serum adiponectin levels increased with increasing age of healthy subjects and in patients with diabetes, in both men and women. Serum adiponectin levels were positively correlated with age in healthy subjects and patients with diabetes, in both men and women. In stepwise multiple regression analysis with serum adiponectin levels as the dependent variable and physiological characteristics as explanatory variables, age was significantly and independently associated with serum adiponectin levels in each of these groups of subjects. CONCLUSIONS: Serum adiponectin levels are significantly and positively associated with age in healthy subjects and in patients with diabetes. This association is independent of renal function, body fat status, glucose metabolism and lipid profiles.

Association of adiponectin with blood pressure in healthy people.

OBJECTIVE: With the increasing prevalence of diseases related to obesity, metabolic syndrome and its key player adiponectin are now attracting considerable attention. Hypoadiponectinaemia is reported to be a risk factor for hypertension and associated with endothelial dysfunction, which is closely related to complications of obesity such as hypertension. As there is limited information regarding serum adiponectin levels in normotensive people, we undertook the large-scale study to determine the association of adiponectin with blood pressure (BP) in mainly normotensive people. DESIGN, PATIENTS AND MEASUREMENTS: In 21 100 Japanese adults (12 363 men and 8737 women) who had no apparent diseases, we examined the relationship between the serum adiponectin concentration and BP by performing a questionnaire survey, physical measurements and measurement of laboratory parameters including the serum adiponectin level. RESULTS: Subjects with hypoadiponectinaemia had higher systolic and diastolic BPs as already reported. And interestingly, subjects with higher adiponectin had lower systolic and diastolic BP. According to linear regression analysis, adiponectin showed a significant negative correlation with systolic and diastolic BP independently of the other variables. Analysis of covariance according to adiponectin quintiles showed that systolic and diastolic BP in highest adiponectin quintile was significantly lower than in other quintiles. CONCLUSIONS: This study revealed that there were significant trends toward lower systolic and diastolic BP with higher adiponectin not only in hypertensive people but also in normotensive people.

Adiponectin negatively correlates with alcoholic and non-alcoholic liver dysfunction: Health check-up study of Japanese men.

AIM: Central obesity, insulin resistance and alcohol consumption are thought to be major risk factors for fatty liver formation. Adiponectin (APN) prevents fatty liver formation, and its serum levels are lower in subjects with central obesity and/or insulin resistance. The aim of this study was to explore the association among serum APN levels, central obesity, insulin resistance and liver dysfunction with or without fatty liver classified by alcohol consumption in healthy subjects. METHODS: A total of 5588 Japanese male subjects who underwent a health check-up were classified into three groups according to alcohol consumption: non- or light drinkers (15 g/day ≥ ethanol); mild drinkers (15 g/day < ethanol ≤ 30 g/day); and moderate- or heavy drinkers (30 g/day < ethanol). Central obesity and insulin resistance were assessed by waist circumference (WC) and Homeostasis Model of Assessment - Insulin Resistance (HOMA-IR), respectively. RESULTS: WC was significantly increased, while HOMA-IR was significantly decreased according to the extent of alcohol consumption. Serum alanine aminotransferase levels were significantly lower and serum APN levels were significantly higher in mild drinkers than in the other two groups. Multiple linear regression analysis showed that serum APN level served as the significant and independent determinant for liver dysfunction in the subjects with fatty liver, irrespective of alcohol consumption. However, WC became a non-significant determinant of liver dysfunction as alcohol consumption increased. CONCLUSION: Hypoadiponectinemia is a significant determinant for steatotic dysfunction for all levels of alcohol consumption, but central obesity was not a significant determinant for alcoholic fatty liver-induced liver dysfunction.

Lower serum level of adiponectin is associated with increased risk of endoscopic erosive gastritis.

BACKGROUND: Obesity is recently known as a risk factor for endoscopic gastritis. Adiponectin is an anti-inflammatory cytokine secreted from fat tissue, and its serum concentrations are reduced in obesity. The relation between adiponectin and gastritis remains unclear. AIMS: The aim of this study was to determine whether lower serum adiponectin level is associated with the risk of endoscopic gastritis. METHODS: We analyzed medical records of participants of a routine health check-up examination. Association among endoscopic findings, serum adiponectin level, and other clinical factors including age, sex, alcohol habit, smoking habit, body mass index (BMI), blood pressure, cholesterol, triglyceride, glucose, and insulin were investigated. Endoscopic erosive gastritis was defined as a flat or minimally depressed white spot surrounded by a reddish area or small elevation with central umbilications mimicking octopus' suckers. RESULTS: A total of 2,400 participants were enrolled. BMI was significantly higher in gastritis-positive participants than in gastritis-negative participants. Serum adiponectin levels were significantly lower in gastritis-positive participants than in gastritis-negative participants. Multivariate logistic regression analysis revealed that lower serum adiponectin level (OR 0.96; 95% CI 0.93-0.99), smoking (OR 0.50; 95% CI 0.30-0.80), higher blood pressure (OR 1.02; 95% CI 1.01-1.03), and duodenitis (OR 1.8; 95% CI 1.00-3.09) were significantly associated with endoscopic erosive gastritis. CONCLUSIONS: Lower serum level of adiponectin may increase the risk of endoscopic erosive gastritis, independently of BMI. Our findings facilitate further study to clarify the role of hypoadiponectinemia in erosive gastritis.

Association of low serum adiponectin levels with erosive esophagitis in men: an analysis of 2405 subjects undergoing physical check-ups.

BACKGROUND: Obesity is a risk factor for gastro-esophageal reflux disease (GERD). It is generally considered that intra-abdominal pressure in obese subjects is involved in the pathogenesis of GERD through acid exposure to the esophagus. Recently, visceral fat has been recognized as an endocrine organ that secretes various adipocytokines including adiponectin. The aim of this study was to elucidate the relation between adiponectin and erosive esophagitis. METHODS: This was a cross-sectional retrospective observational study: 2405 consecutive subjects who underwent screening esophago-gastro-duodenoscopy with serum adiponectin measurement as part of their physical check-up programs were analyzed. Clinical factors were compared between subjects with and without erosive esophagitis. The association between adiponectin and erosive esophagitis was assessed using a bootstrapping re-sampling method after adjustment for factors that tended to be different in univariate analysis. RESULTS: Serum adiponectin levels were significantly lower in those with erosive esophagitis (8.17 µg/ml) than in those without (10.1). The erosive esophagitis group had a greater body mass index (BMI) and waist circumference (WC) and a higher prevalence of hiatal hernia. Using the bootstrap method, with a lower adiponectin cut-off value of 3-7 µg/ml, the lower limit of the 95% confidence interval of the adjusted odds ratio consistently exceeded 1 after adjustment for BMI and hiatal hernia in men. When adjusting for WC instead of BMI, the effect of adiponectin was reduced but remained significant at a lower cut-off value (3-3.5 µg/ml). CONCLUSIONS: Low serum adiponectin levels may be associated with an increased risk for erosive esophagitis in men.