Dizziness
Dizziness is defined as "an imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness".[1] Dizziness is commonly used to designate a whole variety of sensations, from a vague sense of weakness to a definite feeling of spinning. Like pain, dizziness is a purely subjective experience.
Dizziness should be distinguished from the term vertigo. Vertigo is a specific form of dizziness in which a false sensation of movement is present. In dizziness, unlike vertigo, there is no universally accepted definition of the quality of the sensation. Instead, the term may indicate a feeling of weakness, a near loss of consciousness, or general anxiety.
Dizziness should be distinguished from syncope. In syncope, also called fainting, there is loss of consciousness.
Cause/etiology
According to a systematic review of original research articles, the most common causes of dizziness among patients who seek medical care are:[2]
- Vertigo is the cause in 55% of patients
- Peripheral vestibulopathy in 44%
- Central vestibulopathy in 11%
- Cardiac causes of dizziness can cause vertigo according to a separate study[3]
- psychiatric causes in 16%
- other conditions in 26%
- unknown cause in 13%
In this study, serious causes were infrequent: cerebrovascular disease (6%), cardiac arrhythmia (1.5%), and brain tumor (<1%).[2]
The feeling of dizziness is prompted by certain circumstances, such as extreme fatigue or hunger. Dizziness is also commonly felt in abnormal conditions like poor blood perfusion to the brain because of low blood pressure or arrhythmia, and when blood levels of carbon dioxide are driven down by prolonged hyperventilation. Despite the fact that there are situations in which the presence of dizziness is predictable, it remains a misunderstood condition in the health sciences that is sometimes interpreted as an arbitrary complaint by a patient who has no physical illness.
It is doubtful that hyperventilation is a cause of chronic dizziness.[4]
Cultural aspects of dizziness
A feeling of dizziness may be feared, discounted or even welcomed depending on the identity and cultural background of the person experiencing it. In the 19th Century, western girls and women who easily became "faint" were often admired as showing refinement and gentility. On the other hand, admission of feeling faint or dizzy has long been denigrated as showing weakness and can be particularly alarming to athletes and soldiers. Because of the underlying values ascribed to a person experiencing the sensation of dizziness in different cultures, a person may be more or less likely to admit to feeling this sensation.
Chronic non-specific dizziness
For patients experiencing chronic dizziness, without vertigo or evidence of balance problems, the condition is often outside of the ability of the health sciences to remedy in routine care. Dizziness without any component of vertigo is technically called "nonspecific dizziness". The medical view of nonspecific dizziness as a condition tends to be skeptical. For example the definition of dizziness in the Steadman's Medical Dictionary is as follows: Imprecise term commonly used by patients in an attempt to describe various symptoms such as faintness, vertigo, disequilibrium, or unsteadiness. Etymology: A. S. [dyzig,] foolish.
Causes of dizziness that persists for more than two weeks after initially seeking health care are:[5]
- vestibular disorders (29%)
- benign positional vertigo (BPV) (16%)
- psychiatric disorders (6%)
- presyncope (3%)
- dysequilibrium (1%)
- hyperventilation (<1%)
Only 52% of the patients in this study had a single cause.[5]
Medical evaluation of the dizzy patient
There are several important findings in the description of dizziness in addition to the quality of the dizziness. Over-reliance on the quality of the dizziness may lead diagnostic errors.[6]
Prognosis
Among adults over aged 65, one study found that dizziness is a risk factor for stroke only if vertigo is present.[7]
See also
References
- ↑ National Library of Medicine. Dizziness. Retrieved on 2007-12-20.
- ↑ 2.0 2.1 Kroenke K, Hoffman RM, Einstadter D (2000). "How common are various causes of dizziness? A critical review". South. Med. J. 93 (2): 160–7; quiz 168. PMID 10701780. [e]
- ↑ Newman-Toker, David; Fei Dy, Victoria Stanton, David Zee, Hugh Calkins, Karen Robinson (2008-12-01). "How Often is Dizziness from Primary Cardiovascular Disease True Vertigo? A Systematic Review". Journal of General Internal Medicine 23 (12): 2087-2094. DOI:10.1007/s11606-008-0801-z. Retrieved on 2008-12-18. Research Blogging.
- ↑ Hornsveld HK, Garssen B, Dop MJ, van Spiegel PI, de Haes JC (1996). "Double-blind placebo-controlled study of the hyperventilation provocation test and the validity of the hyperventilation syndrome". Lancet 348 (9021): 154–8. PMID 8684155. [e]
- ↑ 5.0 5.1 Kroenke K, Lucas CA, Rosenberg ML, et al (1992). "Causes of persistent dizziness. A prospective study of 100 patients in ambulatory care". Ann. Intern. Med. 117 (11): 898–904. PMID 1443950. [e]
- ↑ Stanton VA, Hsieh YH, Camargo CA, et al (2007). "Overreliance on symptom quality in diagnosing dizziness: results of a multicenter survey of emergency physicians". Mayo Clin. Proc. 82 (11): 1319–28. PMID 17976351. [e]
- ↑ Evans JG (1990). "Transient neurological dysfunction and risk of stroke in an elderly English population: the different significance of vertigo and non-rotatory dizziness". Age Ageing 19 (1): 43–9. PMID 2316424. [e]