@article {1553, title = {Associations of total and high-molecular-weight adiponectin with all-cause and cardiovascular mortality in older persons: the Cardiovascular Health Study.}, journal = {Circulation}, volume = {126}, year = {2012}, month = {2012 Dec 18}, pages = {2951-61}, abstract = {

BACKGROUND: Adiponectin shows opposite associations with adverse outcomes in healthy middle-aged populations (lower risk) and cohorts with prevalent cardiovascular disease, heart failure, or advanced age (higher risk).

METHODS AND RESULTS: In a population-based study of older adults, we examined the relationships of total and high-molecular-weight adiponectin with mortality among subgroups defined by baseline cardiovascular status: No cardiovascular disease, heart failure, or atrial fibrillation (group 1); cardiovascular disease but no heart failure/atrial fibrillation (group 2); and heart failure/atrial fibrillation (group 3). We found significant differences in the associations with all-cause mortality across the groups. The association in group 1 was U-shaped; increasing levels of total adiponectin up to 12.4 mg/L were associated with lower mortality after adjustment for confounders (hazard ratio=0.81 per 1 SD [95\% confidence interval, 0.65-0.95]), but above this cut point, higher levels conferred greater risk (hazard ratio=1.19 [95\% confidence interval, 1.12-1.27]). Further adjustment for diabetes mellitus or insulin resistance, protection against which has been proposed to mediate the beneficial relationships of adiponectin with outcome, attenuated the association in the lower range. There was no significant association in group 2, but in group 3, total adiponectin showed a direct adjusted association. Additional adjustment for putative metabolic/inflammatory intermediates suggested a direct association for group 2, and magnified the one for group 3 (hazard ratio=1.31 [1.15-1.50]). Results were similar for high-molecular-weight adiponectin and for cardiovascular mortality.

CONCLUSIONS: Adiponectin exhibits distinct associations with mortality in elders, which shift from U-shaped to flat to direct with greater baseline cardiovascular dysfunction but become more consistently adverse after accounting for metabolic/inflammatory factors presumed to be favorably regulated by the adipokine. These findings advance understanding of the adiponectin paradox as it relates to older adults.

}, keywords = {Adiponectin, Aged, Aged, 80 and over, Body Mass Index, Cardiovascular Diseases, Female, Health Surveys, Humans, Male, Molecular Weight}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.112.135202}, author = {Kizer, Jorge R and Benkeser, David and Arnold, Alice M and Mukamal, Kenneth J and Ix, Joachim H and Zieman, Susan J and Siscovick, David S and Tracy, Russell P and Mantzoros, Christos S and deFilippi, Christopher R and Newman, Anne B and Djouss{\'e}, Luc} } @article {1356, title = {Total and high-molecular-weight adiponectin and risk of incident diabetes in older people.}, journal = {Diabetes Care}, volume = {35}, year = {2012}, month = {2012 Feb}, pages = {415-23}, abstract = {

OBJECTIVE: To delineate the associations of total adiponectin, high-molecular-weight (HMW) adiponectin, and the HMW-to-total adiponectin ratio with diabetes in older adults.

RESEARCH DESIGN AND METHODS: Total and HMW adiponectin were measured in a population-based study of older adults. The relations of total adiponectin, HMW adiponectin, and their ratio with incident diabetes (n = 309) were assessed in 3,802 individuals.

RESULTS: Total and HMW adiponectin were highly correlated (r = 0.94). Analysis using cubic splines revealed that the associations between total and HMW adiponectin and new-onset diabetes were not linear. Specifically, after adjustment for confounders, there were similar inverse relationships for total (hazard ratio per SD 0.49 [95\% CI 0.39-0.63]) and HMW adiponectin (0.42 [0.32-0.56]) with diabetes up to values of 20 and 10 mg/L, respectively, above which the associations plateaued. These associations persisted after adjustment for potential mediators (blood pressure, lipids, C-reactive protein, and homeostasis model assessment of insulin resistance [HOMA-IR]). There was, however, evidence of interaction by HOMA-IR in the lower range of adiponectin, with stronger inverse associations among insulin-sensitive than insulin-resistant participants. HMW-to-total adiponectin ratio showed a linear adjusted association with outcome, but this was abolished by inclusion of mediating variables.

CONCLUSIONS: In this older cohort, increasing concentrations of total and HMW adiponectin were associated with comparably lower risks of diabetes, but these associations leveled off with further increases above concentrations of 20 and 10 mg/L, respectively. The more pronounced risk decreases at the lower range among participants without insulin resistance support a role for adiponectin that is independent of baseline hyperinsulinemia, but this will require further investigation.

}, keywords = {Adiponectin, Aged, Diabetes Mellitus, Female, Humans, Male, Risk Factors}, issn = {1935-5548}, doi = {10.2337/dc11-1519}, author = {Kizer, Jorge R and Arnold, Alice M and Benkeser, David and Ix, Joachim H and Djouss{\'e}, Luc and Zieman, Susan J and Barzilay, Joshua I and Tracy, Russell P and Mantzoros, Christos S and Siscovick, David S and Mukamal, Kenneth J} } @article {6139, title = {Total and high-molecular-weight adiponectin and risk of coronary heart disease and ischemic stroke in older adults.}, journal = {J Clin Endocrinol Metab}, volume = {98}, year = {2013}, month = {2013 Jan}, pages = {255-63}, abstract = {

CONTEXT: Adiponectin is atheroprotective in the laboratory, but prospective studies have shown opposite associations with cardiovascular disease (CVD) in healthy middle-aged populations (protective) and older cohorts (adverse). Whether this relates to different proportions of high-molecular-weight (HMW) adiponectin is unknown.

OBJECTIVE: The aim of the study was to test the hypothesis that total adiponectin is directly associated, but HMW adiponectin is inversely related, with CVD in older adults.

DESIGN, SETTING, AND PARTICIPANTS: We evaluated 3290 participants free of prevalent CVD in a longitudinal cohort study of U.S. adults aged 65 yr and older.

MAIN OUTCOME MEASURES: We measured incident CVD (n = 1291), comprising coronary heart disease and ischemic stroke.

RESULTS: Total and HMW adiponectin were tightly correlated (r = 0.94). Cubic splines adjusted for potential confounders revealed that the associations of total and HMW adiponectin with CVD were U-shaped, with inflection points of 20 and 10 mg/liter, respectively. After controlling for potential confounding, levels of total and HMW adiponectin below these cutpoints tended to be inversely associated with incident CVD, driven by their significant or near-significant relations with coronary heart disease [hazard ratio (HR), 0.85 per sd increase; 95\% confidence interval (CI), 0.75-96; and HR, 0.87; 95\% CI, 0.75-1.01, respectively]. These associations were abrogated by additional inclusion of putative metabolic intermediates. Above these cutpoints, however, both total and HMW adiponectin were significantly directly associated with CVD after adjustment for confounders and, particularly, mediators (HR, 1.20 per sd increase; 95\% CI, 1.06-1.35; and HR, 1.12; 95\% CI, 1.02-1.24, respectively).

CONCLUSION: In community-living elders, total and HMW adiponectin showed similar U-shaped relationships with CVD. The inverse relation in the lower range, but not the direct association at the higher end, disappeared after inclusion of putative intermediates, suggesting that high levels may reflect adverse processes separate from adiponectin{\textquoteright}s beneficial glycometabolic properties.

}, keywords = {Adiponectin, Adult, Aged, Aged, 80 and over, Brain Ischemia, Cardiovascular Diseases, Case-Control Studies, Cohort Studies, Coronary Disease, Female, Humans, Male, Molecular Weight, Residence Characteristics, Risk Factors, Stroke}, issn = {1945-7197}, doi = {10.1210/jc.2012-2103}, author = {Kizer, Jorge R and Benkeser, David and Arnold, Alice M and Djouss{\'e}, Luc and Zieman, Susan J and Mukamal, Kenneth J and Tracy, Russell P and Mantzoros, Christos S and Siscovick, David S and Gottdiener, John S and Ix, Joachim H} } @article {6137, title = {Relations of plasma total and high-molecular-weight adiponectin to new-onset heart failure in adults >=65 years of age (from the Cardiovascular Health study).}, journal = {Am J Cardiol}, volume = {113}, year = {2014}, month = {2014 Jan 15}, pages = {328-34}, abstract = {

Adiponectin exhibits cardioprotective properties in experimental studies, but elevated levels have been linked to increased mortality in older adults and patients with chronic heart failure (HF). The adipokine{\textquoteright}s association with new-onset HF remains less well defined. The aim of this study was to investigate the associations of total and high-molecular weight (HMW) adiponectin with incident HF (n = 780) and, in a subset, echocardiographic parameters in a community-based cohort of adults aged >=65 years. Total and HMW adiponectin were measured in 3,228 subjects without prevalent HF, atrial fibrillation or CVD. The relations of total and HMW adiponectin with HF were nonlinear, with significant associations observed only for concentrations greater than the median (12.4 and 6.2 mg/L, respectively). After adjustment for potential confounders, the hazard ratios per SD increment in total adiponectin were 0.93 (95\% confidence interval 0.72 to 1.21) for concentrations less than the median and 1.25 (95\% confidence interval 1.14 to 1.38) higher than the median. There was a suggestion of effect modification by body mass index, whereby the association appeared strongest in participants with lower body mass indexes. Consistent with the HF findings, higher adiponectin tended to be associated with left ventricular systolic dysfunction and left atrial enlargement. Results were similar for HMW adiponectin. In conclusion, total and HMW adiponectin showed comparable relations with incident HF in this older cohort, with a threshold effect of increasing risk occurring at their median concentrations. High levels of adiponectin may mark or mediate age-related processes that lead to HF in older adults.

}, keywords = {Adiponectin, Age of Onset, Aged, Biomarkers, Cross-Sectional Studies, Echocardiography, Doppler, Enzyme-Linked Immunosorbent Assay, Female, Follow-Up Studies, Heart Failure, Humans, Incidence, Male, Prognosis, Prospective Studies, Recurrence, Severity of Illness Index, United States, Ventricular Function, Left}, issn = {1879-1913}, doi = {10.1016/j.amjcard.2013.09.027}, author = {Karas, Maria G and Benkeser, David and Arnold, Alice M and Bartz, Traci M and Djouss{\'e}, Luc and Mukamal, Kenneth J and Ix, Joachim H and Zieman, Susan J and Siscovick, David S and Tracy, Russell P and Mantzoros, Christos S and Gottdiener, John S and deFilippi, Christopher R and Kizer, Jorge R} }