Recurrences are common but often occur in clusters.[86]Sahota IS, Maxey C, Pournazari P, et al. Clusters, gaps, and randomness: vasovagal syncope recurrence patterns. JACC Clin Electrophysiol. 2017 Sep;3(9):1046-53.
https://www.jacc.org/doi/10.1016/j.jacep.2017.02.008
http://www.ncbi.nlm.nih.gov/pubmed/29759709?tool=bestpractice.com
In one meta-analysis, 36% of patients in randomized and cohort studies fainted during the study follow-up period (median follow-up 2 years).[87]Pournazari P, Sahota I, Sheldon R. High remission rates in vasovagal syncope: systematic review and meta-analysis of observational and randomized studies. JACC Clin Electrophysiol. 2017 Apr;3(4):384-92.
https://www.jacc.org/doi/10.1016/j.jacep.2016.10.012
http://www.ncbi.nlm.nih.gov/pubmed/29759452?tool=bestpractice.com
The estimated 1-year mortality rate after syncope (all causes) is 8.4%.[88]Solbiati M, Casazza G, Dipaola F, et al. Syncope recurrence and mortality: a systematic review. Europace. 2015 Feb;17(2):300-8.
https://academic.oup.com/europace/article/17/2/300/2802596
http://www.ncbi.nlm.nih.gov/pubmed/25476868?tool=bestpractice.com
The mortality risk is mainly related to cardiovascular causes.[25]D'Ascenzo F, Biondi-Zoccai G, Reed MJ, et al. Incidence, etiology and predictors of adverse outcomes in 43,315 patients presenting to the Emergency Department with syncope: an international meta-analysis. Int J Cardiol. 2013 Jul 15;167(1):57-62.
https://iris.unimore.it/retrieve/handle/11380/793892/171529/1-s2.0-S0167527311021401-main.pdf
http://www.ncbi.nlm.nih.gov/pubmed/22192287?tool=bestpractice.com
Patients with NMRS typically have a better prognosis than patients with cardiac syncope, but injury is a concern due to recurrent falls, especially in older people.[13]Runser LA, Gauer RL, Houser A. Syncope: evaluation and differential diagnosis. Am Fam Physician. 2017 Mar 1;95(5):303-12.
https://www.aafp.org/pubs/afp/issues/2017/0301/p303.html
http://www.ncbi.nlm.nih.gov/pubmed/28290647?tool=bestpractice.com
In one meta-analysis, injury due to vasovagal syncope occurred in one third of patients; the rate of major injury was 13.9%.[89]Jorge JG, Raj SR, Teixeira PS, et al. Likelihood of injury due to vasovagal syncope: a systematic review and meta-analysis. Europace. 2021 Jul 18;23(7):1092-9.
http://www.ncbi.nlm.nih.gov/pubmed/33693816?tool=bestpractice.com