May 22, 2005, Updated September 13, 2012

Dr. Avi Weiss’ research shed new light on previously-held theories regarding rapid postural blood pressure drop.If you want to know about blood pressure, talk to Dr. Avi Weiss.

A senior doctor in the Geriatric Department of Beilinson Hospital in Tel Aviv, the Israeli researcher has devoted the last few years to studying a major problem among the elderly. Many elderly people suffer from problematic rapid drops in blood pressure upon assuming an upright posture from the lying position that are likely to cause falls, injuries, broken hip bones, cerebral incidents, decrease in mental capacities, and even death.

Since 1998, Weiss and his team at Beilinson, have studied over 500 geriatric patients while they were hospitalized in order to gather data and learn more about this dangerous phenomenon, in hopes of reducing its occurrence.

What they found has shed new light on previously-held theories regarding rapid postural blood pressure drop.

Conventional medical thinking dictated that the hours in which a rapid drop in blood pressure was most likely were in the early morning.

But according Weiss’s research, the highest-risk period is right after eating lunch – especially in the summer.

“We found that the highest frequency of incidents appears after lunch because the blood is diverted to the digestive system. This goes against the accepted hypotheses that the phenomenon is more common in the morning, upon rising from sleep, or at night, when the body becomes tired following the day’s activities,” said Weiss.

“We recommend that those patients who suffer from drops in blood pressure after lunch should divide the meals into smaller sections and eat them spread out during the day. This will avoid the accumulation of blood in the digestive system, thus making rapid blood pressure drop less common,” he told ISRAEL21c.

Additional interesting findings revealed that drops in blood pressure are more common in the summer than in the winter.

“It seems quite logical because we’re often more tired in the hot weather and we lose fluids through perspiration. But surprisingly, no study had ever been conducted on this, or published in the English medical literature,” Weiss said.

Weiss attributed the result to either relative dehydration during the hot summer months or blood vessels’ expansion in reaction to the heat, or both.

Amid consulting with patients and receiving phone calls from colleagues, Weiss explained his interest in helping solve the conundrum of rapid postural blood pressure drop in the elderly.

“We’ve been working since 1998 on the problem of rapid blood pressure drop in elderly patients admitted to geriatric wards. There are plenty of reasons for that – we know that when elderly people go from a lying to a sitting position, there’s a tendency for a rapid postural drop in blood pressure,” he said.

Younger people have good autostatic mechanisms – when they shift positions, they resume their normal blood pressure levels usually within fractions of a second. It’s not the same with elderly – especially those who are ill or under many medications as most elderly are.”

Weiss said that the very reason many geriatric patients are hospitalized is the result of damage caused by their wavering blood pressure, but, that the physicians in charge are not always aware of that problem.

“So between January 1999 and December 2000, we observed more than 500 patients, measured the blood pressure in lying and standing positions three times a day, and recorded their heart rate, pulse, as well as other data like demographics, ailments, medications,” he said.

“Our conclusions showed that nearly 68% of the patients suffered from rapid postural blood pressure drop at least once a day. This is considerably higher than in any known studies.

Previously published studies have the overall population at 5-7% and hospitalized elderly at 50%.

Weiss’ research was presented in international and European conferences concerning blood pressure studies that were conducted in Prague, Milan and Paris and was published in the journal Archives of Internal Medicine and the Journal of Human Hypertension.

Another study which Weiss and his team has just completed probes whether accepted facts about medications and illnesses as causes of blood pressure drops are in effect valid. What they found contradicted the norms.

“Antiarrhythmic drugs like the heart medicine digoxyn, for instance, are conventionally known to be one of the causes of postural rapid blood pressure drop. But what we’ve discovered is that these drugs make the heart work more regularly and effectively, and actually prevent the drop from occurring,” said Weiss.

“We also found that patients with orthopedic ailments after surgery – like hip fractures – suffered less from PBPF. This is surprising, since those that fell probably did so due to some kind of PBPF.

“We think, though that the operation and the pain activate a certain group of muscles, so as to compensate for the injured area. This results in more pumping of blood to the heart, thus less instances of BPF.”

According to Weiss, the bottom line in preventing rapid blood pressure drop is awareness.

“It’s important to increase awareness of the elderly population among attending hospital staff and patients’ families. There has to be more care and attention when taking elderly patients out of their beds. Their blood pressure must be monitored several times throughout the day.”

“Strict attention must make certain of adequate hydration and drink. Intensive physiotherapy must be enacted during elderly patients’ hospitalization in order to prevent muscle weakness. Similarly, we must raise the beds in order to activate leg muscles before standing and even carry out therapeutic activities among those suffering from this phenomenon. These recommendations are even important to elderly people living at home.”

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