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Systemic Hypertension, Headache, and Ocular Hemodynamics: Limitations of the Hypothesis  

2012-03-03 17:00:47|  分类: ophthalmology 眼 |  标签: |举报 |字号 订阅

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Limitations of the Hypothesis

A principal limitation of this hypothesis could be the absence of a direct or striking clinical or statistically strong positive link between glaucoma and hypertension. Glaucoma is a term that is applied to several states with either aberration in control of IOP due to anterior segment anatomic aberration involving defective circulation or outflow of aqueous humor or optic nerve head vascular insufficiency in the face of normal IOP. Nevertheless, because headache is a prominent feature of angle-closure glaucoma only, it is essential to explicate the phenomenological and mechanistic differences that underlie IOP elevation between this glaucoma variant and hypertensive headache. Crucially, this hypothesis for hypertension-related headache does not pertain to persistent glaucoma-related anterior segment anatomic and pathophysiologic mechanisms, but to episodic rapid-onset choroidal congestion that stretches the pain-sensitive corneoscleral envelope; increased CBF, in turn, can increase aqueous humor formation and secondarily raise IOP. Of interest, several studies have shown a consistent link between systemic BP and IOP.[29,44,45] Besides, there is no link between severe hypertension, including hypertensive crises in pheochromocytoma, and angle-closure glaucoma. Finally, increased pulsatile CBF is not a feature of glaucoma. On the contrary, pulsatile ocular blood flow is reduced stepwise with elevated IOP.[46] A basic pathophysiologic difference prevails between the 2 entities.

Although eye pain and headache are characteristic features of angle-closure glaucoma, the clinical analogy to hypertensive headache is limited; the absence of typically glaucomatous symptoms, such as visual blurring or loss of visual acuity, colored halos around lights, nausea and vomiting, corneal edema, or fixed semidilated pupils in patients with hypertensive headache, indicates a different mechanistic basis, probably involving a panocular or global corneoscleral distention rather than a predominantly anterior ocular segment aberration.

The second issue that challenges this hypothesis is that the IOP changes seen in patients with hypertension[29,44,45] are relatively small or modest and may not be sufficient to result in headache. First, casual tonometry and even more methodic measurements of IOP can miss biologically significant elevations of IOP.[47]This hypothesis envisions episodic rises of IOP that precede and possibly persist during the headache. Measurement of CBF or IOP during hypertensive headaches has never been carried out; only such aberrations are truly representative for this hypothesis. Second, a reciprocal relation prevails between CBF and relatively higher levels of IOP; the tamponade effect of choroidal congestion and higher IOP dampens CBF and ocular pulsatility. With the onset of hypertensive headache, diminished rather than increased CBF might be expected. Third, the development of headache activates the autonomic nervous system that may tend to lower CBF as well as IOP. Fourth, rapid increases of choroidal perfusion pressure in parallel with high systemic pulse pressure of hypertension can stretch the relatively low-volume ocular globe with only limited alterations of IOP. Finally, several factors affect static and dynamic distensibility of the corneoscleral envelope, particularly with rapid alterations in the volume-pressure relationship.[31] This hypothesis basically invokes rapid-onset panocular distention through choroidal vascular congestion rather than through a primary elevation of IOP. The need for conceptual dissociation between hypertension-related IOP variations and disease entities associated with glaucomatous features appears to be theoretically valid and clinically relevant.

 

References

  1. Janeway TC. A clinical study of hypertensive cardiovascular disease. Arch Intern Med. 1913;12:755-798.
  2. Barlow DH, Beevers DG, Hawthorne VM, Watt HD, Young GAR. Blood pressure measurement at screening and in general practice. Br Heart J. 1977;39:7-17. Abstract
  3. Cooper WD, Glover DR, Hormbrey JM, Kimber GR. Headache and blood pressure: evidence of a close relationship. J Hum Hypertens. 1989;3:41-44.
  4. Vandenburg MJ, Evans SJW, Kelly BJ, Bradshaw F, Currie WJC, Cooper WD. Factors affecting the reporting of symptoms by hypertensive patients. Br J Clin Pharmacol. 1984;18:1895-1945.
  5. Cooper WD, Sheldon D, Brown D, Kimber GR, Isitt VL, Currie WJC. Post-marketing surveillance of enalapril: experience in 11,710 hypertensive patients in general practice. J R Coll Gen Pract. 1987;37:346-349. Abstract
  6. Kjellgren KI, Ahlner J, Dahlof B, Gill H, Hedner T, Saljo R. Perceived symptoms amongst hypertensive patients in routine clinical practice -- a population-based study. J Intern Med. 1998;244:325-332. Abstract
  7. Pietrini U, de Luca M, de Santis G. Hypertension in headache patients? A clinical study. Acta Neurol Scand. 2005;112:259-264. Abstract
  8. Spierings EL. Acute and chronic hypertensive headache and hypertensive encephalopathy. Cephalalgia. 2002;22:313-316. Abstract
  9. Bauer G. Hypertension and headache. Aust N Z J Med. 1976;6:492-497. Abstract
  10. Waters WE. Headache and blood pressure in the community. Br Med J. 1971;(i):142-143.
  11. Weiss NS. Relation of high blood pressure to headache, epistaxis and selected other symptoms. N Engl J Med. 1972;287:631-633. Abstract
  12. Hagen K, Stovner LJ, Vatten L, Holmen J, Zwart JA, Bovim G. Blood pressure and risk of headache: a prospective study of 22 685 adults in Norway. J Neurol Neurosurg Psychiatry. 2002;72:463-466. Abstract
  13. Ghione S. Hypertension-associated hypalgesia. Evidence in experimental animals and humans, pathophysiological mechanisms, and potential clinical consequences. Hypertension. 1996;28:494-504. Abstract
  14. Guasti L, Grimoldi P, Diolisi A, et al. Treatment with enalapril modifies the pain perception pattern in hypertensive patients. Hypertension. 1998;31:1146-1150. Abstract
  15. Fuchs FD, Gus M, Moreira LB, Moreira WD, Goncalves SC, Nunes G. Headache is not more frequent among patients with moderate to severe hypertension. J Hum Hypertens. 2003;17:787-790. Abstract
  16. Gus M, Fuchs FD, Pimentel M, Rosa D, Melo AG, Moreira LB. Behavior of ambulatory blood pressure surrounding episodes of headache in mildly hypertensive patients. Arch Intern Med. 2001;161:252-255. Abstract
  17. Friedman D. Headache and hypertension: refuting the myth. J Neurol Neurosurg Psychiatry. 2002;72:431.
  18. Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders: 2nd edition. Cephalalgia. 2004;24(suppl1):9-160.
  19. Lance JW. Solved and unsolved headache problems. Headache. 1991;31:439-445. Abstract
  20. Strandgaard S, Paulson OB. Cerebrovascular consequences of hypertension. Lancet. 1994;344:519-521.Abstract
  21. Lance JW, Hinterberger H. Symptoms of pheochromocytoma, with particular reference to headache, correlated with catecholamine production. Arch Neurol. 1976;33:281-288. Abstract
  22. Hong YH, Lee YS, Park SH. Headache as a predictive factor of severe systolic hypertension in acute ischemic stroke. Can J Neurol Sci. 2003;30:210-214. Abstract
  23. Bigal ME, Bordini CA, Speciali JG. Etiology and distribution of headaches in two Brazilian primary care units. Headache. 2000;40:241-247. Abstract
  24. Thomas JE, Rooke ED, Kvale W. The neurologists experience with pheochromocytoma. A review of 100 cases. JAMA. 1966;197:754-758. Abstract
  25. Bannister LH, Berry MM, Collins P, Dyson M, Dussek JE, Ferguson MWJ. Gray's Anatomy. 38th ed. New York: Churchill Livingstone; 1995:1232.
  26. Bill A. Blood circulation and fluid dynamics in the eye. Physiol Rev. 1975;55:383-417. Abstract
  27. Kiel JW. The effect of arterial pressure on the ocular pressure-volume relationship in the rabbit. Exp Eye Res. 1955;60:26-78.
  28. Polak K, Polska E, Luksch A, et al. Choroidal blood flow and arterial blood pressure. Eye. 2003;17:84-88.Abstract
  29. Klein BE, Klein R, Knudtson MD. Intraocular pressure and systemic blood pressure: longitudinal perspective: the Beaver Dam Eye Study. Br J Ophthalmol. 2005;89:284-287. Abstract
  30. Ingelsson E, Bjorklund-Bodegard K, Lind L, Arnlov J, Sundstrom J. Diurnal blood pressure pattern and risk of congestive heart failure. JAMA. 2006;295:2859-2866. Abstract
  31. Duke-Elder S. The physiology of the eye and of vision. System of Ophthalmology. Vol 4. London: Henry Kimpton; 1968:411, 276-277, 280-283.
  32. Zuazo A, Ibanez J, Belmonte C. Sensory nerve responses elicited by experimental ocular hypertension. Exp Eye Res. 1986;43:759-769. Abstract
  33. Horven I, Sjaastad O. Cluster headache syndrome and migraine: ophthalmological support for a two-entity theory. Acta Ophthalmol. 1977;55:35-51.
  34. Sjaastad O, Egge K, Horven I, et al. Chronic paroxysmal hemicrania: mechanical precipitation of attacks. Headache. 1979;19:31-36. Abstract
  35. Gupta VK. Ocular compression maneuver aborts benign cough-induced headache. Headache. 2005;45:612-614.Abstract
  36. Gupta VK. Is benign cough headache caused by intraocular haemodynamic aberration? Med Hypotheses. 2004;62:45-48.
  37. Gupta VK. Clopidogrel and atrial shunt closure for migraine: why is migraine aggravated immediately? Heart. December 13, 2005. Available at: http://heart.bmjjournals.com/cgi/eletters/91/9/1173#869 Accessed August 4, 2006.
  38. Gupta VK. A clinical review of the adaptive potential of vasopressin in migraine. Cephalalgia. 1997;17:561-569.Abstract
  39. Weber MA, Fodera SM. Circadian variations in cardiovascular disease: chronotherapeutic approaches to the management of hypertension. Rev Cardiovasc Med. 2004;5:148-155. Abstract
  40. Stergiou GS, Vemmos KN, Pliarchopoulou KM, Synetos AG, Roussias LG, Mountokalakis TD. Parallel morning and evening surge in stroke onset, blood pressure, and physical activity. Stroke. 2002;33:1480-1486. Abstract
  41. Metoki H, Ohkubo T, Kikuya M, et al. Prognostic significance for stroke of a morning pressor surge and a nocturnal blood pressure decline: the Ohasama study. Hypertension. 2006;47:149-154. Abstract
  42. Pointer JS. The diurnal variation of intraocular pressure in non-glaucomatous subjects: relevance in a clinical context. Ophthalmic Physiol Opt. 1997;17:456-465. Abstract
  43. Liu JH, Bouligny RP, Kripke DF, Weinreb RN. Nocturnal elevation of intraocular pressure is detectable in the sitting position. Invest Ophthalmol Vis Sci. 2003;44:4439-4442. Abstract
  44. Nemesure B, Wu SY, Hennis A, Leske MC. Factors related to the 4-year risk of high intraocular pressure: the Barbados Eye Studies. Arch Ophthalmol. 2003;121:856-862. Abstract
  45. Mitchell P, Lee AJ, Rochtchina E, Wang JJ. Open-angle glaucoma and systemic hypertension: the blue mountains eye study. J Glaucoma. 2004;13:319-326. Abstract
  46. Weigert G, Findl O, Luksch A, et al. Effects of moderate changes in intraocular pressure on ocular hemodynamics in patients with primary open-angle glaucoma and healthy controls. Ophthalmology. 2005;112:1337-1342. Abstract
  47. Katz B. Anterior ischaemic optic neuropathy and intraocular pressure. Arch Ophthalmol. 1992;110:596-597.
  48. Gupta VK. Pupillary aberrations and ANS function: challenges to traditional thinking. J Neurol Neurosurg Psychiatry. June 12, 2006. Available at: http://jnnp.bmjjournals.com/cgi/eletters/jnnp.2006.092833v1 Accessed August 4, 2006.
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