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Abstract:
Caird and his colleagues reported posture-dependent falls in systolic blood pressure of 20 mm Hg and more in 24% of a population aged 65 and above. In about 5% of the group, moreover, the falls were in excess of 40 mm Hg. Our investigations in 160 residents in an old people's home in the age range 59-88 years largely confirmed Caird's figures. Using Schellong's test we recorded systolic pressure falls of 20 mm Hg and more in 25% of our subjects. These cases of circulatory dysregulation were all manifestations of the hypodynamic form of the orthostatic syndrome. This means that only systolic blood pressure fell, diastolic pressure as well as heart rate being largely unaffected. The phenomenon appears to be due to age-related deterioration in circulatory regulation; at least no evidence has been found to suggest that it has a specific aetiology. In a double-blind cross-over study the effect of dihydroergotamine (DHE) was compared to placebo in 40 patients. Half the patients were given 2 mg DHE three times daily for 14 days and the other half placebo tablets; following 1 week's wash-out, the treatments were then reversed for a further 2-week period. Schellong's test (measurement of blood pressure and pulse after 10 min in the supine position and then after 1, 2, 5 and 10 min standing) was performed at the beginning and end of each treatment period. The average falls in upright systolic pressure for all 40 patients were as follows: before treatment 20 mm Hg (150 leads to 130); end of placebo period 19 mm Hg (147 leads to 128); end of DHE periods 7 mm Hg (145 leads to 138). The differences between the values recorded after treatment with DHE and the other two values are statistically significant (p less than 0.05). Similarly there was a significant difference in the numbers of patients experiencing dizziness during Schellong's test (16-17 out of 40 patients before treatment and after placebo, 6 out of 38 patients after DHE). From this finding conclusions can be drawn regarding the causes of vertigo in old age.