If the nation’s worst state health systems performed as well as the best, nearly 86,000 fewer people would die prematurely each year, a new report finds.

There’s a nearly fourfold disparity between the best and worst state health systems, according to a new set of rankings from The Commonwealth Fund, a foundation that promotes improved health care for vulnerable and underserved populations. Not only would thousands of premature deaths be prevented, the report found, but if states provided vulnerable populations with the same quality of health care their more-advantaged residents receive, some 33,000 more infants would live to see their first birthday.

“[H]ealthier children are more likely to succeed in school and grow up to continue to participate in the workforce in the future,” the report found. “A healthy population is thus instrumental in maintaining strong local and state economies, as well as the nation’s economic health and well-being.”

Those states with the worst performance are located almost entirely in the south and southeast United States. Those with the best are mostly in the northeast and Midwest.

In Massachusetts, 36 percent of the non-elderly population earning less than twice the poverty level was uninsured or underinsured — the lowest share in the nation. Ten states had rates of more than 60 percent: Alaska, Colorado, Florida, Idaho, Montana, Nevada, New Mexico, Texas, Utah and Wyoming.

Among some factors, low-income residents in states with the best health systems received better care than higher-income residents in lesser states, according to the report. And there were much smaller disparities among states for high-income individuals. The report concludes that covering more individuals will close the income and geographic gaps.

The report measured 30 indicators grouped into four broad categories: access and affordability, prevention and treatment, potentially avoidable hospital use and healthy lives. The standout leaders were Hawaii, Wisconsin, Vermont, Minnesota, Massachusetts and Connecticut.

State health system scorecard. (Source: The Commonwealth Fund.)