Why are Nantucketers healthier than the rest of the United States?
Researchers have long pondered the health effects of where people live. The blue zone theory, for instance, suggests that residents of five geographic areas across the globe, from Japan to California, live longer lives based on a variety of shared characteristics such as diet, physical activity, and social engagement. A recent study gives Nantucket its own distinction, identifying the island as a surprising standout in the fight against cancer.
The study, published in the Journal of the American Medical Association (JAMA), found that cancer mortality across the United States decreased by 20 percent between 1980 and 2014. But what the study revealed about Nantucket was startling: The cancer death rate on the island had dropped an astonishing 42 percent, one of the largest measured decreases in the country during the study period. The finding was so dramatic, Boston’s NPR station, WBUR, dubbed it “The Nantucket Effect.”
Using death records from the National Center for Health Statistics, as well as population counts from the Census Bureau and the Human Mortality Database, researchers from the University of Washington looked at twenty-nine different types of cancers and mortality rates based on county of residence. The study found the overall 20 percent decline in cancer mortality across the country, but noticed important changes in trends, patterns, and differences at the county level, with Nantucket being one of the major outliers.
Since 1980, for example, the death rate in cases of stomach cancer on Nantucket fell by 69.3 percent, while testicular cancer mortality dropped 72.1 percent. The four drivers in cancer mortality, according to lead researcher Ali Mokdad, include: socioeconomic factors, such as wealth and education; access to healthcare and preventative screenings through health insurance; the quality of the medical care available; and preventable risk factors like smoking, alcohol consumption, and diet.
“If you look at any county and watch these four drivers, you can understand what is happening,” says Mokdad, a professor of global health at the University of Washington. “To me, this is a great success story and something to be maintained. If I’m a county health official [on Nantucket,] I’m thinking what we have been doing has been good, and we should keep it up.”
So what has Nantucket been doing that could produce such an enormous shift over the past twenty-five years? Island health officials and physicians are cautiously optimistic that the study may show the result of incremental improvements in Nantucket’s medical resources and network, as well as positive lifestyle changes among island residents. But they are also hesitant to draw strong conclusions from such a study given the relatively small number of cancer cases for a county with only 15,000 to 20,000 year-round residents.
“The availability of tertiary care has helped, and some of the treatment modalities have started making more sense, so I think those are factors,” says Dr. Tim Lepore, who operates a primary care practice and has been a surgeon at Nantucket Cottage Hospital since 1980. “There’s also improved care on the island with the hospital having stepped up oncology services — that being chemotherapy and having oncologists come out here.”
The six-year-old clinical partnership between Nantucket Cottage Hospital and the Massachusetts General Hospital Cancer Center brings some of Boston’s best oncologists to the island for patient consultations and treatment, allowing Nantucket residents to access much of their care without having to travel to the mainland. The director of the program, Dr. Richard Penson, says he hopes that the JAMA study and others like it might help confirm that people can reduce their risk of cancer by taking control of their lifestyles, or at the very least lead to a better understanding of how to reduce cancer mortality.
“The most likely cause is fewer of the big risk factors (such as) smoking, viruses, obesity, etc., in this population,” Penson says. “Healthy lifestyles are a major driver of reduced cancer risk. Better access to oncology services is important, and perhaps multidisciplinary care is the most important.”
One factor that may be influencing Nantucket’s cancer mortality rate, Lepore suggests, is the close-knit nature of the island community. If you have the opportunity to ask your physician or nurse about a health concern when you bump into them while running an errand, it could potentially lead to an earlier diagnosis and treatment.
“If you see your healthcare providers at the grocery store, it’s not quite as intimidating as having to go to someplace where you don’t know the people,” Lepore says. “There aren’t the barriers to health care that happen in other places. It’s very different than if you’re in Roxbury and can’t figure out how to get into [Boston Medical Center]. Here, it’s immediately available.”
While Nantucket Health Director Roberto Santamaria also noted that the island’s small number of cancer cases could result in big percentage shifts on a year-to-year basis, he agrees with Lepore’s assessment of the factors the island could have in its favor when it comes to cancer mortality. “Access to healthcare is an issue on the island, but there’s also the flipside in that we’re so small, and people really know their providers,” he says. “We’re not at the level of access to care set by federal standards, but we’re much better than we were in 1980. Between 1980 and 2014, we’ve tripled the amount of doctors on-island.”
Beyond the skepticism of the study results due to Nantucket’s relatively small number of cancer cases, the conclusions also came as a surprise to many island residents who are keenly aware that the island’s incidence rate for many types of cancer is far higher than the statewide incidence rate. Federal statistics gathered during Nantucket Cottage Hospital’s most recent Community Health Needs Assessment show that the island has a higher incidence rate for breast cancer, colorectal cancer, and melanoma, among others, compared to the statewide incidence rates for those cancers.
The sense that Nantucket residents might be at a heightened risk for cancer is only magnified by the close-knit nature of the community. If you live on Nantucket year-round, chances are you’re going to hear about the latest islander to receive a cancer diagnosis, or see that GoFundMe page posted by a friend of a friend on Facebook seeking donations to help cover the cost of medical care for them.
“In a small community, what is visible isn’t always the same as what is actually happening,” Santamaria says. “We will always have a little higher incidence rate because of our increased population in the summer.”
Even so, there are perhaps other factors at play that could be affecting the island’s cancer mortality rate, including the reduction in smoking among Nantucket residents, along with the general lifestyle advantages of living on an island thirty miles out to sea, island health officials suggested. Nantucket is indeed routinely ranked as the healthiest county in Massachusetts, and recently earned the top spot for health outcomes in the Robert Wood Johnson Foundation’s annual county health rankings, which measures length and quality of life. “We have a general stress-free environment in comparison to the mainland, and stress is a factor in higher mortality,” Santamaria says. “So is there a ‘Nantucket effect’? I would say yes.”