Health: Expanding the View

Research on the Big Island examines how diabetes affects different races.

Epidemiologist Andrew Grandinetti studies diabetes and its complications. photo: Daeja Fallas

There are fewer than 7,000 people in Kohala, an old plantation town on the Big Island. For Dr. Andrew Grandinetti, an epidemiologist who studies diabetes among multiethnic populations, little Kohala offers something special. Area residents are almost evenly divided among Asians, Native Hawaiians and Caucasians, says Grandinetti, an affiliate with the Department of Public Health Sciences at the John A. Burns School of Medicine. Because of the area’s racial mix, Grandinetti has been conducting studies in Kohala for more than a decade. His research is funded by the National Institutes of Health.

It’s been known for some time, says Grandinetti, that minorities suffer higher rates of diabetes than whites. But, he adds, researchers have typically viewed Caucasians as the norm and other ethnicities as the exception. Grandinetti disputes that claim, hypothesizing instead that Caucasians “maladapted” to stave off diabetes. While traditional populations continued to contend with “feast and famine periods,” says Grandinetti, those living in Western countries adopted sedentary lifestyles. Now, as traditional cultures shift toward the easy life, their bodies remain equipped for the next famine.

Most studies, says Grandinetti, have focused on diabetes among Native Hawaiians only. “One of my pet peeves is that Asians as well as Pacific Islanders are at very high risk for diabetes,” he says. Based on a 1,500-person sample, Grandinetti found that Asians and Native Hawaiians have equal diabetes rates. Moreover, the prevalence of diabetes among both groups is three times higher than among Caucasians (Grandinetti hopes to publish these findings in Ethnicity and Disease later this year).

But risk factors for diabetes aren’t constant across populations, says Dr. Marjorie Mau, professor and chair of the Department of Native Hawaiian Health at the University of Hawai‘i. Researchers, she says, have looked at Native Hawaiians because people assume that obesity, high among Hawaiians, is the only risk factor for diabetes. But risk is more associated with body mass index (BMI), which is calculated from a person’s height and weight, than weight alone. While Asians must typically keep their BMI below 23 to prevent diabetes, both Native Hawaiians and Caucasians can keep a BMI of 26 and below, Mau says. Asians she adds, often distribute weight around their abdomen, and “When it comes to diabetes risk, the worst place to put your fat is in your belly.”

But Hawaiians are at the greatest risk for diabetes-related complications. “Hawaiians do have higher mortality rates from diabetes, so it’s possible that they’re not getting optimal care,” Grandinetti says, adding that the issue is still being studied.

While it’s unclear if the ethnic differences surrounding diabetes are genetic, environmental or both, Mau says that’s not the point: “Nobody’s going to go back to subsistence living when [today] you can go to the store and buy fish. The better question would be how best to find a way to stay healthy and eat a diet that’s appropriate for your genetic makeup.”