Effect of posture on blood pressure in the elderly.

The blood pressure was measured in the lying position and after I minute's quiet standing in 494 people aged 65 or more living at home. A drop of 20 mmHg or more in systolic pressure occurred on standing in 24 per cent, of 30 mmHg or more in 9 per cent, and of 40 mmHg or more in 5 per cent. The frequency of a fall on standing increased with age. Comparison between subjects whose pressure fell on standing and those in whom it did not showed that there