A new study by researchers in the US found that people with advanced dementia are frequently given antibiotics toward the end of life, and has thrown into question whether this practice should be curtailed in view of the increased risk of developing drug resistant superbugs.

The study is the work of Drs Erika D’Agata and Susan L Mitchell of the Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, and is published in the 25th February issue of the Archives of Internal Medicine.

Advanced dementia patients in nursing homes are at high risk of infections and antimicrobial exposure near the end of life, wrote the researchers.

D’Agata and Mitchell studied a group of 214 residents, of average age 85.2, with advanced dementia being cared for in 21 nursing homes in and around Boston.

The residents were assessed between 2003 and 2006 and then every three months for up to 18 months. At each assessment, the number and type of antibiotics prescribed, with reasons (indication), were noted from records kept at the nursing home.

They found that:

  • Over an average 322 days of follow up, 142 (66.4 per cent) of the group received at least one course of antibiotics (mean number of courses per resident was 4.0 with standard deviation of 3.7).
  • The mean number of days of antibiotic treatment for every 1,000 resident days for the whole group was 53.0 (standard deviation 4.3).
  • The most frequently prescribed antibiotics were quinolones and third-generation cephalosporins.
  • These accounted for 38.3 and 15.2 per cent of 540 prescribed antimicrobial therapy courses, respectively.
  • The most common reason for an antibiotic prescription was respiratory tract infection, which accounted for 46.7 per cent of all courses.
  • Of the 99 residents who died, 42 (42.4 per cent) of them had received antibiotics in the 2 weeks before death.
  • Among these 99, the number who received antibiotics went up significantly as they approached death.
  • The proportion of residents taking antibiotics in the last two weeks of life was seven times greater compared with six to eight weeks before death.
  • The number of antibiotics prescribed and the days of therapy per 1,000 resident-days also went up significantly as death approached.
  • 30 of the 72 courses (41.7 per cent) taken in the last two weeks of life were given intravenously as opposed to by mouth (this could be distressing and uncomfortable for patients with advanced dementia).

D’Agata and Mitchell concluded that:

“Persons with advanced dementia are frequently exposed to antimicrobials, especially during the 2 weeks before death.”

With regard to the implications of this practice they suggested it should be evaluated with respect to two things: “the individual treatment burden near the end of life and its contribution to the emergence of antimicrobial resistance in the nursing home setting.”

Writing in an editorial in the same issue of the journal, Drs Mitchell J. Schwaber and Yehuda Carmeli of the Tel Aviv Medical Center in Israel commented that:

“The findings in this study require the medical community to ask whether the extensive use of antibiotics in this particular patient population is appropriate, taking two factors into consideration: the benefit to the patient treated and the risk imposed on other patients.”

They are not suggesting a flat refusal to give antibiotics to severely demented elderly people, or even that policies restricting their use should be introduced. They suggest antibiotics should be considered alongside every other carefully weighed decision such as resuscitation and major surgery.

As well as weighing up the the interests of the patient and the risk to others, they concluded that:

“All such decisions must ultimately be made individually, based on the medical situation and the expressed wishes of the patient and family, as well as on the physician’s judgment of the benefits and risks entailed in treating vs. not treating.”

The controversy about the public health implications arises because previous research has shown that nursing homes can harbour drug resistant bacteria, and these can spread into hospitals when nursing home residents are admitted.

An Associated Press report notes the comments of various experts, discussing the implications of this study. A geriatrician and ethicist at the University of Chicago Medical Center, Dr Daniel Brauner, said being more careful with antibiotics means doctors would have to keep a much closer watch on nursing home residents. But, he said “I’m sure a lot of these antibiotics were prescribed over the telephone”.

Another problem of course, even with close monitoring, is that the doctor sometimes can’t tell if the patient is approaching death. Dr Eric Tangalos, a geriatrician at the Mayo Clinic told the Associated Press that:

“Until that decision is made that death is imminent, there’s always hope. People do recover from those infections.”

On the other hand, is the problem of what constitutes quality of life in those last few weeks, as Bruce Jennings, a bioethicist with a research institute on medical ethics, the Hastings Center, put it:

“You might rescue the patient from life-threatening pneumonia and they live a few days, weeks or even months longer. But the extra time you have bought them by that rescue is not beneficial.”

Mitchell said doctors should discuss these things with the patient’s family, in the same way as they disucss whether a feeding tube should be used. She also commented that none of the residents in the study had made living wills stating their wishes on antibiotic treatment.

Over 5 million Americans are living with dementia, about 70 per cent of whom will be cared for in nursing homes as they approach the end of their lives.

“Patterns of Antimicrobial Use Among Nursing Home Residents With Advanced Dementia.”
Erika D’Agata; Susan L. Mitchell.
Arch Intern Med. 2008;168(4):357-362.
Vol. 168 No. 4, February 25, 2008.

Click here for Abstract.

Sources: Article abstract, JAMA press release, Associated Press.

Written by: Catharine Paddock, PhD