A woman dying of Alzheimer's has a fever. Should she be given antibiotics?

Many people would say yes. But a provocative new study suggests that antibiotics are overused in people dying of dementia diseases and should be considered more carefully because of the growing problem of drug-resistant superbugs.

The study raises ethical questions about when it is acceptable to withhold perhaps futile treatment and let people die, and whether public health issues should ever be considered.

"Advanced dementia is a terminal illness," said study co-author Dr. Susan Mitchell, a senior scientist with the Harvard-affiliated Hebrew Senior Life Institute for Aging Research in Boston. "If we substituted 'end-stage cancer' for 'advanced dementia,' I don't think people would have any problem understanding this."

Many experts, including the Alzheimer's Association, consider Alzheimer's and other dementias to be fatal brain diseases. Patients die of infections such as pneumonia and other complications, but the underlying cause is damage to brain cells.

In the study, more than 200 people with advanced dementia from Boston-area nursing homes were followed for 18 months or until their deaths. Almost half died during that time. All the patients failed to recognize loved ones, had stopped speaking, were unable to walk or feed themselves and were incontinent.

"They were at what anyone would consider the very final stage," Mitchell said.

Researchers reviewed medical records to see what kind of care they were given and found that 42 percent received antibiotics — many intravenously — within two weeks of their deaths. The closer they were to death, the more likely they were to receive antibiotics.

The study appears in Monday's Archives of Internal Medicine.

Antibiotic overuse contributes to the rise of superbugs, so experts have been calling on doctors to curb the liberal prescribing of antibiotics in many types of patients, including children with earaches and adults with sore throats.

Nursing homes often harbor drug-resistant bacteria, prior studies have shown, and residents can spread dangerous infections when they are admitted to hospitals.

Dr. Daniel Brauner, a geriatrician and ethicist at the University of Chicago Medical Center who was not involved in the study, said cautious use of antibiotics in nursing homes would require doctors to more closely monitor residents.

"But the standard of care (in nursing homes) is for doctors to see residents once a month, or once every two months," Brauner said. "I'm sure a lot of these antibiotics were prescribed over the telephone."

Doctors should discuss antibiotics with family, just as they would discuss placing a feeding tube, Mitchell said. None of the residents in the study who received antibiotics had living wills spelling out their wishes on antibiotic treatment, she said.

If the family's goal is to keep their loved one comfortable, rather than to prolong life, alternatives such as oxygen and Tylenol can help, she said.

Giving antibiotics is sometimes appropriate for such patients, she acknowledged.

"Maybe it's important for the family for the patient to live two weeks longer, or if they have a bad pneumonia and they're suffering and they're coughing," she said.

An accompanying editorial in the journal cautions that public policy limiting antibiotics to patients with advanced dementia would be "ethically untenable." But the editorial calls on doctors to consider the public health ramifications when prescribing antibiotics to such patients.

Other experts disagreed.

"Until that decision is made that death is imminent, there's always hope," said Dr. Eric Tangalos, a geriatrician at Mayo Clinic in Rochester, Minn., who was not involved in the study. "People do recover from those infections."

Once called "the old man's friend," pneumonia can be an acceptable end when a patient's quality of life is extremely low and everyone agrees the patient would want a dignified death, said another expert not involved in the study.

"You might rescue the patient from life-threatening pneumonia and they live a few days, weeks or even months longer," said Bruce Jennings, a bioethicist with the Hastings Center, a research institute on medical ethics. "But the extra time you have bought them by that rescue is not beneficial."