Risk Factors of Incident Heart Failure in Patients with Acute Myocardial Infarction

• Main Authors: Yu-YaLin, 林于雅
• Other Authors: Yea-Huei Kao
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/13442154499797479027

碩士 === 國立成功大學 === 臨床藥學與藥物科技研究所 === 101 === Background Due to the medical improvements in the past decades, the survival of acute myocardial infarction (AMI) patients has improved. However, with the damaged myocardium from infarction, survivors of AMI are at higher risk of developing heart failure (HF). The development of HF is associated with a significantly elevated risk of death. Previous studies indicated that about 13~76% patients would develop HF after AMI. The variability in the incidence of post-MI HF may be explained by heterogeneity in study periods, study populations and study design. There is a paucity of information regarding this issue in Taiwan. In addition, the time periods of most studies were before 2000 and therapies have continued to evolve. A better understanding of the incidence of post-MI HF in Taiwan and the factors involved in HF development would help to improve care of AMI patients. Methods We conducted a retrospective cohort study by using 1999~2009 National Health Insurance Research Database (NHIRD). Patients aged≧18 years, with no history of HF, who hospitalized with a first AMI between January 1, 2002 and December 31, 2008 were identified and followed up for 1 year. The primary outcomes were HF and severe HF, and secondary outcome was HF or death. HF was defined as an outpatient visit or hospitalization for HF (ICD-9 428, 402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, 404.93). Severe HF was defined as a hospitalization for HF and prescription of loop diuretics or intravenous inotropic agents. We evaluated the incidence of HF during AMI hospitalization, 30 days, 6 months and 1 year after discharge. Further, we estimated factors related to HF by using Cox proportional hazard model with adjusting baseline characteristics, comorbidities, medical interventions and other covariates. Results A total of 42,011 patients were identified. After excluding those who died, 14.83% had HF and 12.78% had severe HF during AMI hospitalization. After discharge, the cumulative incidence of HF at 30 days, 6 months and 1 year was 9.59%, 14.21% and 16.76%. The cumulative incidence of severe HF was 1.59%, 3.83% and 4.84%, respectively. The most important factors related of HF were age≧65 years, history of DM and ischemic stroke, use of loop diuretics within 30 days after discharge and recurrent MI. Patients can be classified into low-, intermediate-, and high-risk groups according to the numbers of above factors. The risk of developing HF was 3.37 fold and 5.99 fold higher in the intermediate- and high-risk groups compared with low-risk group. The use of statins (HR 0.85, 95% CI 0.78-0.92) and other lipid-lowering agents (HR 0.61, 95% CI 0.48-0.78) significantly reduced the risk of HF. The use of beta-blockers (HR 0.86, 95% CI 0.76-0.98) and statins (HR 0.82, 95% CI 0.72-0.94) significantly reduced the risk of severe HF. Conclusions Survivors of AMI without prior HF remain at risk of developing HF in Taiwan and most episodes occur early after AMI. We identified 5 most important factors related to HF which may help to stratify risk level. The use of beta-blockers and lipid-lowering agents is associated with a reduced risk of HF.