Epidemiology

Epidemiology of neurally mediated syncope

The prevalence of syncope in the general population is extremely common. Almost everybody seems to have either experienced or witnessed an episode. Syncopal events often do not reach medical attention, particularly in the young in whom most episodes are considered to be innocent neurally mediated events[1],[1, 1, 2, 3, 3, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 8, 9, 9, 9, 9, 9, 10, 11, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 16, 17, 18, 18, 18, 18, 18, 18, 18, 18, 18, 19, 20, 20, 21, 21, 21, 22, 23, 23, 24, 25, 26, 26, 26, 26, 27, 28, 28, 29, 30, 30, 31, 31, 32, 32, 33, 34, 35, 36, 37, 37, 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 41, 41, 42, 42, 42, 43, 43, 43, 43, 43, 44, 44, 45, 46, 47, 48, 48, 49, 50, 51, 51, 52, 53, 54, 55, 56, 57, 58, 59, 59, 59, 59, 59, 59, 60, 61, 62, 63, 64, 65, 65, 66, 67, 67, 67, 67, 68, 68, 68, 68, 68, 69, 70, 70, 70, 70, 71, 72, 72, 73, 73, 74, 75, 75, 75, 75, 75, 76, 77, 78, 79, 79, 80, 80, 81, 82, 82, 83, 84, 85, 85, 86, 87, 88, 89, 90, 91, 92, 92, 93, 94, 95, 96, 97, 98, 99, 99, 100, 101, 101, 102, 103, 104, 105, 106, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133],[42].

Patients with presumed neurally mediated syncope present themselves to general practitioners according to a bimodal age distribution (fig. 2) with a first peak at the age of 15 years, and a second peak in ollder adults and elderly [79]. ~Figure 2~ Typical vasovagal syncope is less common in these older subjects. It is not unusual that the episodes of vasovagal syncope an older patient experiences are far les typical than vasovagal syncope at younger age. Thus, neurally mediated syncope may be considered as a chronic life long condition, with different clinical presentation and triggers among episodes [134],[79],[81].

In older subjects cardiac causes of syncope, orthostatic and postprandial hypotension and carotid sinus hypersensitivity are more frequent [135],[136],[137, 138]. This can be attributed to diminished efficiency of cardiovascular regulatory systems, to medication affecting orthostatic blood pressure control and to increased prevalence of organic disease (e.g. structural heart disease, cardiac arrhythmia’s [139]. In the elderly, multiple causes of syncope are often present and the medical history may be less reliable than in the young, for example syncope may be erroneously reported as a fall [140],[135],[141],[142].

References

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2. Wieling W, Ganzeboom KS, and Saul JP. Reflex syncope in children and adolescents. Heart. 2004 Sep;90(9):1094-100. DOI:10.1136/hrt.2003.022996 |
38. Ganzeboom KS, Colman N, Reitsma JB, Shen WK, and Wieling W. Prevalence and triggers of syncope in medical students. Am J Cardiol. 2003 Apr 15;91(8):1006-8, A8. DOI:10.1016/s0002-9149(03)00127-9 |
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134. Kurbaan AS, Bowker TJ, Wijesekera N, Franzén AC, Heaven D, Itty S, and Sutton R. Age and hemodynamic responses to tilt testing in those with syncope of unknown origin. J Am Coll Cardiol. 2003 Mar 19;41(6):1004-7. DOI:10.1016/s0735-1097(02)02967-4 |
135. Kapoor WN. Syncope in older persons. J Am Geriatr Soc. 1994 Apr;42(4):426-36. DOI:10.1111/j.1532-5415.1994.tb07493.x |
136. Youde J, Ruse C, Parker S, and Fotherby M. A high diagnostic rate in older patients attending an integrated syncope clinic. J Am Geriatr Soc. 2000 Jul;48(7):783-7. DOI:10.1111/j.1532-5415.2000.tb04753.x |

137. & Lipsitz pmid=12180246

139. Brady PA and Shen WK. Syncope Evaluation in the Elderly. Am J Geriatr Cardiol. 1999 May;8(3):115-124.
140. McIntosh S, Da Costa D, and Kenny RA. Outcome of an integrated approach to the investigation of dizziness, falls and syncope in elderly patients referred to a 'syncope' clinic. Age Ageing. 1993 Jan;22(1):53-8. DOI:10.1093/ageing/22.1.53 |
141. Benke T, Hochleitner M, and Bauer G. Aura phenomena during syncope. Eur Neurol. 1997;37(1):28-32. DOI:10.1159/000117400 |
142. Kenny RA. Syncope in the elderly: diagnosis, evaluation, and treatment. J Cardiovasc Electrophysiol. 2003 Sep;14(9 Suppl):S74-7. DOI:10.1046/j.1540-8167.14.s9.8.x |