(Reuters Health) - Mortality rates are lower in American communities with more primary care physicians than in areas of the country with fewer doctors, a study suggests.

Overall in the U.S., the total number of primary care physicians rose from 196,014 in 2005 to 204,419 in 2015, the study found. But because of disproportionate losses of providers in rural areas, the average number of primary care physicians for every 100,000 people in the population declined from 46.6 to 41.1 during the same period.

Each 10 additional primary care physician per 100,000 people was associated with a 51.5 day increase in life expectancy, the study also found. Every 10 extra primary care doctors was also tied to declines of up to 1.4 percent in mortality rates from common causes like cancer, heart disease and respiratory disorders.

“Greater supply of primary care physicians appeared to increase the chances that a person would be treated for cardiovascular disease risk factors like high blood pressure or high cholesterol, or caught early for major cancers like breast cancer or colon cancer,” said lead study author Dr. Sanjay Basu of Stanford University in California.

“While primary care physician availability relates to important goals like longer life and lower death rates, the number of primary care doctors is dwindling,” Basu said by email. “We need to do more to attract great medical students into the primary care field.”

Primary care physicians are typically responsible for routine health screenings and preventive medicine as well as diagnosis, management and treatment of a wide variety of chronic health problems. While previous research has linked a greater supply of these providers to lower death rates, much of this research hasn’t accounted for individual patient and community characteristics that might influence longevity, researchers note in JAMA Internal Medicine

To investigate how the supply of primary care doctors impacts mortality rates, Basu’s team examined data from 3,142 U.S. counties, plus 7,144 primary care service areas and 306 hospital referral regions.

Unlike some previous studies, this one accounted for regional characteristics like number of hospital beds, poverty levels, population density, education levels and home values as well as individual patient characteristics like smoking habits and obesity.

The study also looked at the availability of specialists. For every 10-physician increase in specialists, researchers saw a 19.2 day increase in life expectancy.

The study wasn’t a controlled experiment designed to prove whether or how the supply of primary care physicians might directly impact life expectancy or mortality rates. It also wasn’t designed to identify steps patients might take to live longer.

Patients can’t change health policy or the number of doctors working in their community on their own, but there’s still plenty people can do to take charge of their own health, said Dr. Sondra Zabar of New York University School of Medicine in New York City.

“People should establish care at a practice before they get sick, make sure that they are living a healthy lifestyle and having age appropriate preventative care performed,” Zabar, author of an accompanying editorial, said by email. “They should understand the office’s policy for sick visits, and do everything they can to get in if needed; sometimes, the squeaky wheel does get the grease.”

Individuals, working as a community, can also advocate for policies that promote primary care throughout the country, Zabar said. This starts with recruiting more medical students to enter primary care, but also needs to include salary increases and changes in care delivery that make the job more satisfying and effective.

“The current system does not make it financially sustainable for primary care physicians to hire the necessary support staff to allow them to spend more time seeing patients in way that this is satisfying, high quality and career sustaining,” Zabar said.

SOURCE: bit.ly/2EgmCYu JAMA Internal Medicine, online February 18, 2019.