Table 1. – Main evidence that supported the recommendation of influenza vaccination in cardiac patients.
| Author | Year | n | Main conclusions |
|---|---|---|---|
| Nichol KL et al.7 | 2003 | 286 383 elderly | Influenza vaccine reduced overall mortality by 48%, hospitalizations for heart disease by 19%, and stroke by 16-23% |
| Yap FHY et al.8 | 2004 | 17 226 admissions for NCD | Influenza caused a 45.6% increase in hospitalizations for HF |
| Sandoval C et al.9 | 2008 | 5448 patients with systolic ventricular dysfunction | The risk of hospitalization for HF is 8-10% higher during the influenza season, regardless of how it is defined |
| Jorge JEL et al.10 | 2009 | 6596 hospitalizations for HF | The seasonality with the highest number of hospitalizations for decompensated HF also occurs in tropical regions |
| Estabragh ZR & Mamas MA11 | 2013 | 40 trials | Influenza leads to direct effect: myocarditis with cardiogenic shock, increased AMI, decreased cardiovascular mortality after vaccination |
| Wu WC et al.12 | 2014 | 107 045 patients with HF | Influenza vaccination reduced mortality of patients with HF in 30 days and 1 year |
| Caldeira D et al.13 | 2015 | 4 trials | Influenza vaccination is effective in secondary prevention in patients with cardiovascular disease. Data is lacking to prove the same action in primary prevention |
| Blaya-Nováková V et al.14 | 2016 | 227 984 patients followed for 5 years | Influenza vaccination reduced risk of global winter mortality by 41% per year |
| Fang YA et al.15 | 2016 | 4406 patients with CKD and age ≥55 years. | Elderly people with chronic kidney disease who received an annual influenza vaccination have a lower risk of hospitalizations for HF |
NCD: chronic noncommunicable diseases; HF: heart failure; AMI: acute myocardial infarction; CKD: chronic kidney disease.