Is the Structure of SNAP Linked to Cyclical Illness?

Every five years Congress sets the stage for a contentious political fight over the reauthorization of funding for the United State’s federal farming and food policies. At stake are hundreds of billions of dollars spread across the federal government in an omnibus bill, and the 2014 Farm Bill just passed by Congress and signed by President Obama was no exception. The growing prominence of fiscal conservatism coupled with disagreement on the government’s proper role in the social safety net meant that a majority of the contention over the bill surrounded spending on the Supplemental Nutrition Assistance Program (SNAP, formally known as food stamps), as its title accounts for the majority of the bill’s funding. However, the eventual decision to cut billions from the program over 10 years could have serious health implications, as researchers from the Department of Medicine at University of California, San Francisco (UCSF) note in a recent Health Affairs article.

Helping more than 47 million Americans afford adequate diets in 2013 with benefit transfers, SNAP is the largest anti-hunger program in the country. However, because the benefits are only meant to be a supplement to a family’s food budget and are allocated at the beginning of the month, they often run out before the month’s end, and therefore are not a full solution to food insecurity in the country. Research has repeatedly linked food insecurity to adverse health outcomes, but Seligman et al attempt to look at whether the once-a-month nature of the benefits can be linked to cyclical health problems. They focus on hypoglycemia—low blood glucose—since it is an immediate consequence of food insecurity. To study this relationship they examine hospital admissions rates for hypoglycemia across income groups and find that risk for admission increases in the last week of the month for low-income groups, but not for those in the high-income population.

Data on hospital admissions between 2000 and 2008 for the study come from California’s Office of Statewide Health Planning and Development (OSHPD), which houses cross-sectional administrative data on admissions to accredited hospitals in the state. The sample is limited to patients ages eighteen and older, admitted from the home rather than another institution (like a prison or nursing home), in order to isolate the true impact of food insecurity cycles on adults. The researchers also track admissions related to appendicitis to serve as a control, since the monthly admissions count is similar, but should be independent of food access. Both types of admissions were verified using the International Classification of Diseases.

To construct rough income classifications, the researchers use data from the Internal Revenue Service (IRS) to link ZIP codes of patient’s residences to the mean household income in each ZIP code. Next, to allow for variation in cutoff over time, the patients are labeled as low-income when the linked mean income for the ZIP code was in the lowest decile of incomes for patients admitted that year. Finally, controlling for demographics and admission year and month allows the researchers to further isolate the day of the month as the risk factor for hypoglycemia admissions.

From all of this, the researchers note a 27 percent increase in the rate of admissions for hypoglycemia during the last week of the month for those categorized as low-income. There was no increase in admissions for the non-low-income population, or in appendicitis-related admissions in either population. Furthermore, excluding members of the homeless population strengthened the results, suggesting that their more time-volatile food access was crowding out the true relationship.

On November 1, 2013 all of the nearly 50 million monthly SNAP participants experienced a cut in benefits as a benefits boost from the American Recovery and Reinvestment Act (ARRA) ended prematurely. The 2014 Farm Bill cut more from the program, threatening the food security of millions of Americans. Research like Seligman et al’s suggests that these changes need to be viewed in light of their full impact, including health inequities.

Feature Photo: cc/(rick)