***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Various adipokines are reported to be associated with the development of heart failure ( HF ) through insulin resistance and chronic inflammation . Omentin-1 is a novel adipokine and is associated with incident coronary artery disease . However , it remains unclear whether serum omentin-1 levels are associated with cardiac prognosis in patients with HF . Methods We measured serum omentin-1 levels at admission in 136 consecutive patients with HF , and 20 control subjects without signs of significant heart disease . We prospect ively followed patients with HF to endpoints of cardiac death or re-hospitalization for worsening HF . Results Serum omentin-1 levels were markedly lower in HF patients with cardiac events compared with to without . The patients who were in New York Heart Association ( NYHA ) functional class IV showed significantly lower serum omentin-1 levels compared to those in class II and III , whereas serum omentin-1 levels did not correlate with serum brain natriuretic peptide levels ( r = 0.217 , P = 0.011 ) . We divided the HF patients into three groups based on the tertiles of serum omentin-1 level ( low T1 , middle T2 , and high T3 ) . Multivariate Cox hazard analysis showed that the lowest serum omentin-1 level ( T1 ) was independently associated with cardiac events after adjustment for confounding factors ( hazard ratio 5.78 , 95 % confidence interval 1.20 - 12.79 ) . We divided the HF patients into two groups according to the median serum omentin-1 levels . Kaplan-Meier analysis revealed that the patients with low serum omentin-1 levels had a higher risk of cardiac events compared with those with high serum omentin-1 levels ( log-rank test p < 0.001 ) . Conclusion Decreased serum omentin-1 levels were associated with a poor cardiac outcome in patients with HF BACKGROUND Epidemiological studies have reported that patients with type 2 diabetes mellitus ( DM ) have increased mortality and morbidity from cardiovascular diseases , independent of other risk factors . However , most of these studies have been performed in selected patient groups . The purpose of the present study was prospect ively to assess the impact of type 2 DM on cardiovascular morbidity and mortality in an unselected population . METHODS A total of 13,105 subjects from the Copenhagen City Heart Study were followed up prospect ively for 20 years . Adjusted relative risks of first , incident , admission for , or death from ischemic heart disease , acute myocardial infa rct ion , or stroke , as well as total mortality in persons with type 2 DM compared with healthy controls , were estimated . RESULTS The relative risk of first , incident , and admission for myocardial infa rct ion was increased 1.5- to 4.5-fold in women and 1.5- to 2-fold in men , with a significant difference between sexes . The relative risk of first , incident , and admission for stroke was increased 2- to 6.5-fold in women and 1.5- to 2-fold in men , with a significant difference between sexes . In both women and men the relative risk of death was increased 1.5 to 2 times . CONCLUSIONS In persons with type 2 DM , the risk of having an incident myocardial infa rct ion or stroke is increased 2- to 3-fold and the risk of death is increased 2-fold , independent of other known risk factors for cardiovascular diseases OBJECTIVE Omentin is a protein expressed and secreted from visceral but not subcutaneous adipose tissue , which increases insulin sensitivity in human adipocytes . However , its pathophysiologic role in humans remains largely unknown . The objective of this study is to assess plasma omentin-1 levels in patients with type 2 diabetes mellitus ( T2DM ) and matched control subjects and to investigate the effects of liraglutide on plasma omentin-1 levels in patients with T2DM . PATIENTS AND METHODS Thirty T2DM patients with poor glycemic control after more than 3 months of treatment with one or two OHA(s ) ( T2DM ) , and 30 matched normal glycaemic controls ( NGT ) participated in the study . The T2DM group was given an injection of liraglutide once-daily for 16 weeks . Plasma omentin-1 levels were measured by enzyme-linked immunosorbent assay and the relationship between plasma omentin-1 levels and metabolic parameters was also analyzed . RESULTS Plasma omentin-1 levels were lower in T2DM than in the control ( 19.3 ± 4.0 μg/L vs. 26.4 ± 6.0 μg/L , P < 0.01 ) . Plasma omentin-1 levels increased significantly in T2DM patients after treatment with liraglutide compared with pre-treatment ( 19.3 ± 4.0 μg/L vs. 21.2 ± 3 . 9 μg/L , P < 0.01 ) . In all diabetic patients , multiple regression analysis showed that FINS and HOMA-IR were independently associated with plasma omentin-1 levels . CONCLUSIONS In T2DM patients  , plasma omentin-1 levels decreased , but significantly increased after the treatment with liraglutide and metformin . These data suggest that liraglutide may play a role in increasing omentin-1 levels in T2DM patients 
    Output:
    
Conclusion We found that serum omentin level is significantly lower in T2DM and IGT patients but not in T1DM ones .
These data could be used by clinicians for early diagnosis and management of diabetes .