Doctors from Harvard have an intriguing suggestion for saving 32,000 lives each year: Make sure all senior citizens who wind up in the hospital are treated by female doctors.

After examining the medical records of Medicare patients from across the country, the Harvard researchers calculated that 10.82% of those treated by physicians who were women died within 30 days of being admitted to the hospital. Among patients treated by male physicians, the 30-day mortality rate was 11.49%, according to a study published this week in JAMA Internal Medicine.

That gender gap persisted even after the researchers accounted for factors like the age, gender and income of patients, how sick those patients were when they first checked into the hospital, the resources of the hospitals and the experience of the doctors. In that analysis, the Harvard team found that 11.07% of patients treated by women died within 30 days of being hospitalized, compared with 11.49% of patients treated by men.

The results held up across a wide range of medical conditions, according to the study.


Among patients treated for acute kidney failure, those cared for by female physicians had a 30-day mortality rate of 12.54%, compared with 13.3% for patients cared for by male physicians. Patients admitted for an irregular heart rhythm had a 5.08% chance of dying within 30 days if their doctor was a woman and a 6.02% chance if their doctor was a man. Pneumonia patients treated by women also had an advantage over those treated by men (10.11% versus 11.03%), and the same was true for sepsis patients (23.05% versus 25.09%).

All of these differences were too large to be due to chance, the researchers reported.

The trend was similar for patients admitted to hospitals with congestive heart failure, urinary tract infections and gastrointestinal bleeding, although in these cases the advantage of being treated by a female doctor was smaller and could have been a statistical fluke, according to the study.

Death is a great thing to avoid after going to the hospital. So is being discharged and then re-admitted within 30 days. On that score, patients treated by women had better outcomes than patients treated by men if they were hospitalized for pneumonia, congestive heart failure, gastrointestinal bleeding, sepsis, chronic obstructive pulmonary disease or urinary tract infections. In all of these cases, the advantage of having a female physician was large enough to be statistically significant.


The researchers, led by Dr. Yusuke Tsugawa of the Harvard T.H. Chan School of Public Health, took great pains to make sure their results were valid. They analyzed more than 1.5 million hospitalizations between 2011 and 2014, and these cases involved 58,344 internists (18,751 women and 39,593 men).

On the whole, female doctors treated fewer hospitalized patients than their male counterparts (132 versus 181 per year), and a higher proportion of their patients were women (62.1% versus 60.2%). They were also more likely to work in hospitals that were large, nonprofit and/or affiliated with a medical school.

To make more of an apples-to-apples comparison, the study authors repeated their analysis using data only from hospitalists. These doctors only treat hospitalized patients, and since they work in shifts, their patients essentially are randomly assigned. Even so, female hospitalists had better outcomes (10.8% of their patients died within 30 days of being admitted to the hospital and 14.64% were re-admitted within 30 days) than male hospitalists (11.17% of patients died within 30 days and 15.11% were re-admitted), according to the study.

The researchers also reran the numbers using only hospitals without intensive care units, since male doctors may be more likely to work in ICUs, where patients are sicker. Once again, female doctors had better outcomes (11.16% of their patients died within 30 days of being admitted to the hospital and 15.34% were re-admitted within 30 days) than male doctors (11.78% of patients died within 30 days and 15.94% were readmitted).


Even when the researchers extended their follow-up window from 30 to 60 days, women outperformed men by a small but statistically significant margin, according to the study.

Overall, Medicare patients in hospitals were about 4% less likely to die within 30 days of being admitted if their doctor was a woman instead of a man. Considering that more than 10 million Medicare patients wind up in hospitals each year, the lives of about 32,000 senior citizens could be saved if patients treated by men were treated by women instead.

An all-female doctor corps isn’t likely, so a more practical goal is for men to have the same patient outcomes as women. This will require more research, since it’s not clear what useful things women are doing that men aren’t.

Previous studies have found that women doctors are more likely than their male counterparts to provide preventive care, follow official clinical guidelines, practice evidence-based medicine and offer “psychosocial counseling,” among other things. But researchers have yet to link any specific doctoring practice to patient outcomes, Tsugawa and his colleagues noted.


Even so, the results counter the idea that male doctors — who outnumber female doctors by a margin of 2 to 1 — deserve the higher pay they typically receive, according to an editorial that accompanied the study.

“Some have suggested that the burden of home responsibilities, leave for childbearing, or part-time schedules might undermine the quality of female physicians’ work and explain male physicians’ higher salaries,” wrote JAMA Internal Medicine editor Rita Redberg, a cardiologist at UC San Francisco, and Anna Parks, an internal medicine resident at UC San Francisco. “The evidence shows the opposite.”

karen.kaplan@latimes.com

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