Food insecurity and glycemic control among low-income patients with type 2 diabetes

OBJECTIVE

To determine whether food insecurity—the inability to reliably afford safe and nutritious food—is associated with poor glycemic control and whether this association is mediated by difficulty following a healthy diet, diabetes self-efficacy, or emotional distress related to diabetes.

RESEARCH DESIGN AND METHODS

We used multivariable regression models to examine the association between food insecurity and poor glycemic control using a cross-sectional survey and chart review of 711 patients with diabetes in safety net health clinics. We then examined whether difficulty following a diabetic diet, self-efficacy, or emotional distress related to diabetes mediated the relationship between food insecurity and glycemic control.

RESULTS

The food insecurity prevalence in our sample was 46%. Food-insecure participants were significantly more likely than food-secure participants to have poor glycemic control, as defined by hemoglobin A_1c ≥8.5% (42 vs. 33%; adjusted odds ratio 1.48 [95% CI 1.07–2.04]). Food-insecure participants were more likely to report difficulty affording a diabetic diet (64 vs. 49%, P < 0.001). They also reported lower diabetes-specific self-efficacy (P < 0.001) and higher emotional distress related to diabetes (P < 0.001). Difficulty following a healthy diet and emotional distress partially mediated the association between food insecurity and glycemic control.

CONCLUSIONS

Food insecurity is an independent risk factor for poor glycemic control in the safety net setting. This risk may be partially attributable to increased difficulty following a diabetes-appropriate diet and increased emotional distress regarding capacity for successful diabetes self-management. Screening patients with diabetes for food insecurity may be appropriate, particularly in the safety net setting.The epidemic of type 2 diabetes has hit the poor particularly hard. Low socioeconomic status is associated with a higher prevalence of diabetes and a greater risk for diabetes complications (1–3). There are likely many specific elements of poverty that predispose adults to diabetes and poor diabetes control, but a great number of these potentially predisposing factors have not been fully investigated.Food insecurity has been postulated as one mechanism by which poverty might predispose adults of low socioeconomic status to poor diabetes control (4). Food insecurity refers to going hungry or being at risk for going hungry because of the inability to afford food. It exists “whenever the availability of nutritionally adequate and safe foods or the ability to acquire acceptable foods in socially acceptable ways [e.g., without resorting to emergency food supplies, scavenging, stealing, or other coping strategies] is limited or uncertain” (5). In 2010, 14.5% of U.S. households were food-insecure, representing 32 million adults (6).A recent study conducted with a nationally representative sample (National Health and Nutrition Examination Survey) of low-income adults found that among patients with a known diagnosis of diabetes, 69% of food-insecure and 49% of food-secure adults were unable to achieve a hemoglobin A_1c (HbA_1c) ≤7% (7). Studies among children with type 2 diabetes have demonstrated higher HbA_1c values among children living in food-insecure households compared with children living in food-secure households (8). However, the association between food insecurity and glycemic control has not been evaluated in clinical populations of adult patients with diabetes, and mechanisms for a relationship between food insecurity and glycemic control remain unclear.Food insecurity is a multidimensional concept, encompassing reductions in food quantity and food quality. Other studies suggest that food insecurity may increase patients’ difficulty following a diabetes-appropriate diet because they shift their dietary intake toward inexpensive, calorically dense foods, which generally include a high proportion of added fats, added sugars, and other refined carbohydrates, to maintain caloric needs (9). These foods generally make glycemic control more difficult to achieve. However, we hypothesized that additional mechanisms existed by which food insecurity may directly influence glycemic control. For example, food insecurity may reduce self-efficacy, defined as confidence in one’s ability to successfully manage all of the things necessary to take care of one’s own health, or it may increase emotional distress regarding diabetes management. Reduced self-efficacy and emotional distress related to diabetes may both interfere with patients’ ability to manage their diabetes (10–13).Our objective was to determine whether food insecurity was independently associated with poor glycemic control in a clinical population of low-income adults with diabetes. We hypothesized that the association between food insecurity and glycemic control would be mediated by increased difficulty following a healthy diet, decreased diabetes-specific self-efficacy, and greater emotional distress related to diabetes among the food-insecure participants.