Popping more than five pills a day may increase frailty in the elderly, say scientists who suggest that the medications interact to affect our ability to function well as we age.

Frailty is a problem associated with aging. Someone who is frail can be weak, have less endurance, and be less able to function well. Frailty increases the risk for falls, disability, and even death.

As we age, we tend to develop a number of chronic health conditions and concerns. Often, managing health problems can mean that older adults may take many different medications.

When older adults take five or more medicines (a scenario called "polypharmacy"), it can increase the risk for harmful side effects, researchers said.

Scientists from German Cancer Research Centre (DKFZ) and University of Heidelberg in Germany examined information from nearly 2,000 participants of a large study of older adults to learn how taking more than five medicines might affect frailty in older adults.

Follow-ups on participants were conducted after two, five, eight and 11 years. People in the study were between 50- and 75-years-old when the study began.

At the eight-year follow-up, study physicians visited the participants at home for a geriatric assessment.

Participants were asked to bring all medications they took – both prescription and over-the-counter (OTC) – to assess the kinds and number of medications participants were taking.

The researchers then separated participants into three groups – those who took upto 4 medicines (non-polypharmacy); those who took five to nine medicines (polypharmacy); and thise who took 10 or more medicines (hyper-polypharmacy).

Two pharmacists individually reviewed all medications taken and excluded medicines and supplements that were not known to cause side effects.

After adjusting for differences in patient characteristics including illnesses, researchers found that people who were at risk for frailty, as well as people who were frail, were more likely to be in the polypharmacy or hyper-polypharmacy groups compared with people who were not frail.

Researchers also found that people who took between five to nine medicines were 1.5 times more likely to become frail compared with people who took fewer than five medications.

People who took more than 10 medicines were twice as likely to become frail as people who took less than five.

They concluded that reducing multiple avoidable prescriptions for older adults could be a promising approach for lessening the risks for frailty.

The medicines can interact with each other and with the human body in harmful ways, researchers said. As a result, the risk for falls, delirium, and frailty also increases.

The study was published in the Journal of the American Geriatrics Society.