Blood pressure drugs help even the most frail elderly live longer, and older people who are healthier get the biggest benefit, Italian researchers say. 

"We knew that high blood pressure medication was protective in general among older people, however, we focused on whether it is also protective in frail patients with many other medical conditions who are usually excluded from randomized trials," said lead author Dr. Giuseppe Mancia, professor emeritus at the University of Milano-Bicocca in Milan.

For the study, his team collected data from more than 1 million people aged 65 and older in northern Italy who had received three or more blood pressure medication prescriptions. 

The investigators also looked at the outcomes of older people with a variety of health conditions. 

For those in good health at the outset of the study, the probability of death over seven years was 16%. That rose to 64% for patients who were in very poor health. 

The researchers found that people who took their blood pressure medications regularly were 44% less likely to die during the study if they started in good health while those who were in poor health were 33% less likely to die compared to older people who did not adhere to their medication regimen.

The same pattern was seen for heart disease deaths. 

"Our findings definitely suggest that even in very frail people, antihypertensive treatment reduces the risk of death; however, the benefits may be smaller in this group," Mancia said in an American Heart Association news release. 

He urged doctors to do their best to encourage patients to take their medicine, because "medications do nothing if people don't take them." 

The report was published June 8 in the journal Hypertension.