title: Vitamin C Deficiency, High-Sensitivity C-Reactive Protein, and Cardiac Event-Free Survival in Patients With Heart Failure.
abstract: BACKGROUND
  Vitamin C is related to lower levels of high-sensitivity C-reactive protein (hsCRP), an inflammatory biomarker that predicts cardiovascular disease. Whether vitamin C deficiency is associated with hsCRP and cardiac events in heart failure (HF) patients has not been examined.
  
  
  OBJECTIVE
  The aim of this study is to determine the relationships among vitamin C intake, serum levels of hsCRP, and cardiac events.
  
  
  METHODS
  A total of 200 HF patients completed a 3-day food diary to determine vitamin C deficiency and provided blood to measure serum levels of hsCRP. Patients were followed for 2 years to obtain data on cardiac event-free survival. Moderation analyses with hierarchical logistic and Cox regressions were used for the data analysis.
  
  
  RESULTS
  Seventy-eight patients (39%) had vitamin C deficiency and 100 (50%) had an hsCRP level higher than 3 mg/L. Vitamin C deficiency was associated with an hsCRP level higher than 3 mg/L in the hierarchical logistic regression (odds ratio, 2.40; 95% confidence interval, [1.13-5.10]; P = .023). Vitamin C deficiency (hazard ratio, 1.68; 95% CI, 1.05-2.69, P = .029) and hsCRP level higher than 3 mg/L (hazard ratio, 1.79; 95% CI, 1.07-3.01; P = .027) predicted shorter cardiac event-free survival in hierarchical Cox regression. The interaction of hsCRP level higher than 3 mg/L and vitamin C deficiency produced a 2.3-fold higher risk for cardiac events (P = .002) in moderation analysis. Higher level of hsCRP predicted shorter cardiac event-free survival only in patients with vitamin C deficiency (P = .027), but not in those with vitamin C adequacy.
  
  
  CONCLUSIONS
  Vitamin C deficiency moderated the relationship between inflammation and cardiac events in patients with HF. Future study is required to determine whether adequate intake of vitamin C could play a protective role against the impact of inflammation on cardiac events in HF patients.
authors.affiliation: Eun Kyeung Song, PhD, RN Associate Professor, Department of Nursing, College of Medicine, University of Ulsan, Korea. Seok-Min Kang, MD, PhD Professor, Division of Cardiology, Yonsei Cardiovascular Center and Cardiovascular Research Institute, Severance Hospital, Seoul, Korea.
authors.forename: Eun Kyeung
authors.initials: EK
authors.lastname: Song
authors.forename: Seok-Min
authors.initials: SM
authors.lastname: Kang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001206:Ascorbic Acid Deficiency / Q000097:blood* / Q000150:complications* / Q000401:mortality; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D004032:Diet; D018572:Disease-Free Survival; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000150:complications / Q000401:mortality*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D016016:Proportional Hazards Models; D011446:Prospective Studies
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein