People in Michigan with low incomes may be more likely to develop brain cancer

May 25 2004

The study, which looked at more than 1,000 cases of people with brain cancer during a two-year period (1996-1997), was published in the recent edition of Neurology, the scientific journal of the American Academy of Neurology.

The study, which was led by Paula Riess Sherwood from MSU’s College of Nursing, compared the rate of brain cancer among people with low income – as defined as those who qualified for Medicaid – to all other people who developed brain cancer in Michigan.

Sherwood and colleagues found that among low-income patients there were 14.2 cases of people with brain cancer per 100,000 people. That compared with 7.5 cases per 100,000 for all other persons.

The researchers aren’t sure why low income is associated with higher rates of brain cancer.

“Poverty may accelerate the onset of cancer in people who are biologically predisposed to develop it,” Sherwood said. “Low-income status is also associated with environmental factors such as exposure to toxins, quality of nutrition and shelter, and education and health factors.”

While it’s possible that the results are because people with brain tumors become eligible for Medicaid due to disability from the tumor, the researchers felt there were other reasons for the results.

“The short survival time for this type of cancer, combined with the Medicaid requirements that you spend your assets and be disabled for at least 12 months, may make it difficult for a middle-class person to become eligible for Medicaid during the two-year period of the study,” Sherwood said.

She added that further analysis of only those who were eligible for Medicaid before their diagnosis supported the study findings.

The greatest difference in cancer rates was among younger people. Men under the age of 44 with low incomes were at least four times more likely to develop brain cancer than those not classified as having low income.

Women with low incomes under the age of 44 were at least 2.6 times more likely to develop brain cancer than those who were not classified as low income.

The study was supported by the MSU Institute for Health Care Studies, College of Nursing, College of Human Medicine, and Department of Family Practice; the Michigan Department of Community Health; the National Institute for Nursing Research/National Institutes of Health; the American Cancer Society; and the Walther Cancer Institute.