Low Blood Pressure Isn’t a Rare Event in Seniors

Orthostatic hypotension (a fall in blood pressure on standing up) is quite common in older folk.  Many seniors take medications which have blood-pressure lowering effects, or have chronic diseases that are associated with malfunction of the autonomic nervous system, such a diabetes or Parkinson’s disease. A study conducted in Ireland investigated the frequency of this condition, and reported in the Journal of the American Geriatrics Society.

More than 440 older adults (average age 72, 72% were female) wore a blood pressure monitoring device to measure orthostatic hypotension on a single occasion.  The average systolic blood pressure of the participants was 160 mm Hg. 

Initial orthostatic hypotension was diagnosed when there was a drop of 40 mm Hg or greater in systolic blood pressure within 15 seconds of rising from a lying to a standing position.  This occurred in 21% of the participants; they were more likely to have fallen recently, to be taking 5 or more medications, and to meet criteria for frailty.

In addition to ‘initial orthostatic hypotension’, there were two other types: ‘small drop, fast over-recovery’, seen in 25%, with a 16 mm Hg drop within 30 seconds and full recovery in 30 seconds; and ‘medium drop, slow recovery’, seen in 54%, with a 35 mm Hg drop within 30 seconds, and gradual return to near-baseline in about  2 minutes. 

This study shows that significant orthostatic hypotension is surprisingly common in seniors.  Doctors should routinely ask their older patients about postural dizziness, and check for orthostatic changes during an office visit.  Medications may need adjustments, and other possible causes for postural hypotension eliminated.