Dear Doctor: I've read about a recent study that found that elderly patients with female doctors fared better than those who were treated by men. I wonder -- what do Dr. Ko and Dr. Glazier think about these results?

Dear Reader: You're referring to the results of a study performed by Harvard researchers, published in December 2016 in the journal JAMA Internal Medicine. To say that it caused a bit of a stir is an understatement. Our colleague Dr. Ashley gave his take on these findings yesterday. Our reactions follow later.

Researchers analyzed data from more than 1.5 million Medicare patients 65 and older who were hospitalized between January 2011 and December 2014. What they found was that patients whose doctors were women were less likely to be readmitted to the hospital in the next 30 days, and had lower mortality rates than the patients who were treated by men.

This particular study didn't look into the reasons why, but the authors cited prior studies that found differences in how women and men practice medicine. Specifically, the research suggests that female doctors are more likely to adhere to clinical guidelines, provide more preventive care and communicate more effectively than their male peers.

The Harvard study was prompted, in part, by the fact that women doctors now account for one-third of all physicians and one-half of medical students. Researchers were interested to learn whether career interruptions to start a family, the challenges of home-life balance, and the resulting increase in part-time employment might compromise the quality of care.

So what did we think of the results?

Dr. Glazier: My gut reaction is that it is very hard to generalize. As a patient, I have had both men and women who were extraordinary and compassionate physicians. And I have had teachers, mentors and colleagues who are exceptional, irrespective of their gender.

Considering that this is a single study of modest statistical significance, I don't give it tons of credence. What I would say is that it is paramount to find a doctor with whom you connect both personally and professionally, someone who is compassionate, kind and smart, all qualities that transcend gender.

Dr. Ko: As a female physician early in my career, I am naturally delighted to hear the findings. Medicine has historically been dominated by men, who have been seen as more intelligent and more capable than women. The results are validating and confirm my role to perform this noble work.

The authors admit they can't answer the question "Why?" But since prior studies suggest that women tend to communicate better, listen more effectively and have more emotional intelligence, then the message here is that communication is key. Our training of young physicians should focus on honing these skills and exemplifying these qualities.

The danger is that some patients may oversimplify these results, assuming that to prevent death and re-hospitalization, they need a female physician. But the truth is that there are as many male physicians who are compassionate communicators as there are women physicians who lack those qualities.

What I do hope is that all physicians will take a cue from these results to embrace the qualities and behaviors that may contribute to better care.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Do hospitalized patients really get better care from female doctors compared to men, as a new study -- and now many headlines -- claim?

Dear Reader: My initial reaction when I saw this study was one of denial. As a man, I viewed the study -- and the host of media articles reporting on it -- with something like hostility; it seemed no less than an attack on my gender. After I calmed down a bit, I read through the research.

The study, published recently in JAMA Internal Medicine, looked at a random sample of data -- totaling more than 1.5 million hospitalizations -- from four years of hospitalizations among Medicare patients being cared for by general internists. The authors separated the patients into two groups based on the gender of their physicians, then evaluated quality of care by the death rates of these patients within a 30-day period after hospitalization and also by the rates of readmission to the hospital after being discharged.

The authors found that the death rates of patients cared for by female internists were slightly lower than the death rates of patients cared for by male internists: 11.07 percent versus 11.49 percent. This was not a staggering difference -- amounting to one fewer death in 233 patients -- but still, it was a difference. Further, readmission rates were lower for patients of female doctors compared to patients of male doctors: 15.02 percent versus 15.57. This means one fewer readmission in 182 patients.

Even as a man playing devil's advocate, I can't blame confounding factors -- differences in patient characteristics -- for the findings. Female doctors took care of more female patients, slightly fewer patients with heart disease, lung disease and diabetes, but slightly more patients with kidney disease. But these were only minimal differences, and the authors took those differences into account, making adjustments for them in their findings.

Yet there were two differences between the female and male doctors that may be of substance: the physicians themselves. Female physicians in the study were on average 5 years younger than their male counterparts (42.8 years versus 47.8 years). Not to be ageist, but younger doctors may have a greater ability to use hospital computer systems, may be more likely to utilize social services for their patients, and may be more willing to alter their practices based on the latest studies.

Another important aspect is that female physicians on average took care of fewer hospitalized patients than their male counterparts, with female internists taking care of an estimated 132 hospitalized patients per year versus male internists' 181. The busier schedule of the male internists may increase the chances that some aspects of care will be negatively affected. The authors tried to correct for both the age and patient load issues, but that's not easy to do.

As provocative as this new study is, it's far from conclusive. A 2013 study in the Journal of the American Board of Family Medicine found no differences in care between male and female physicians in the rates of death, hospitalizations or health care expenditures.

In summation, this research does nonetheless offer a reminder to all physicians, regardless of gender or age, that many factors affect patient death rates and readmissions -- and we can't afford to let any of them fall through the cracks.

Tomorrow, my colleagues Dr. Glazier and Dr. Ko will cover this study.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: One of my resolutions for the new year was to become a vegan, and now my girlfriend is saying I'll have to take supplements to get enough vitamin B12. Why can't I get B12 in my diet, and what will happen if I fall short?

Dear Reader: Your girlfriend has done her homework -- vitamin B12 is a nutrient that is essential to human health. And while it occurs naturally in a wide range of animal foods, B12 is not found in any plant foods. As a vegan, you're now going to have to rely on supplements to be sure you get enough B12.

Why is it so important?

Vitamin B12 is a bit of a workhorse. Not only does it play a key role in the proper functioning of the brain and the nervous system, it's crucial to the production of red blood cells in the bone marrow. As though that wasn't enough, B12 also aids in DNA and RNA synthesis, and is involved in the metabolism of carbohydrates, fats and proteins. Research shows that B12 also has a hand in maintaining mood and memory.

The body does not store B12, so you need to ingest it every day. Beef liver and clams have the highest concentrations of the nutrient. It is also present in varying quantities in red meat, eggs, poultry, shellfish, milk and milk products. Many breakfast cereals and some dairy products are fortified with B12. For vegans, there are non-dairy milks, meat substitutes and nutritional yeast products to which B12 has been added. Dietary supplements are widely available.

What happens when B12 is in short supply?

Considering all the roles the nutrient plays in health and well-being, the list of symptoms is long and sometimes quite serious. People with a B12 deficiency may feel weak and tired, the result of the vitamin's role in producing the red blood cells that carry oxygen throughout the body. Since B12 helps maintain the protective sheath around your nerves, a lack of the vitamin can lead to strange sensations like numbness or tingling, as well as problems with balance or walking. Mood and memory may also suffer.

In extreme cases, B12 deficiency can lead to megaloblastic anemia, a blood disorder in which the red blood cells produced in the bone marrow are unusually large, malformed and immature.

And while your girlfriend is right about your need for vigilance in getting enough B12, she may do well to examine her own B12 status. Recent studies suggest that up to 40 percent of the population, vegan or not, may be flirting with B12 insufficiency. Due to physiological changes associated with aging, the elderly are at increased risk of vitamin B12 deficiency. Individuals who have undergone weight-loss surgery must also make a special effort to get enough of the nutrient.

As for you, a newly minted vegan, we recommend that you seek professional advice, preferably from your family doctor, to be certain that you forge a wise nutritional course.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095.)