| dc.description.abstract | Background: Greater than one third of US adults have prediabetes, rising to nearly half of adults over the age of 65. Increased cardiometabolic health risks exist already in prediabetes and incur costs greater than $40 million per year. Less than 12% of individuals with prediabetes are aware of having increased risk of type 2 diabetes and infrequently receive resources to prevent the progression. Limited data exist regarding contributors to clinical decision-making when prediabetes develops. Diet is a modifiable risk factor influencing the risk of diabetes. Assessing patterns of intake enables the study of potential synergistic effects of habitual dietary consumption rather than studying individual nutrients in isolation. Previous methods to investigate the relationship between diet and diabetes risk are limited to deriving patterns that only describe intake among the group or outcomes related to diabetes, but not both. Little is known about nutrient intake of individuals with prediabetes that influence risk of diabetes development. Methods: Two studies were conducted to investigate the research questions of this dissertation. In the first study, we performed a retrospective analysis of 3,675 adults with newly developed prediabetes (indicated by American Diabetes Association diagnostic criteria: hemoglobin A1c (HbA1c) 5.7-6.4%, fasting blood glucose 100-125 mg/dL, or 2-hour glucose following an oral glucose tolerance test 140-199 mg/dL) in two primary care clinics at the University of Kansas Health System. Clinical data entered into the EPIC electronic health record was captured using the i2b2-based clinical data repository tool, HERON. We assessed rates and predictors of prediabetes diagnosis, referrals to nutrition, weight management, or psychology, and prescriptions for metformin or a weight loss medication that occurred within six-months of meeting prediabetes criteria. In the second study, we performed a tertiary analysis that included 1,674 participants enrolled in the Vitamin D and Type 2 Diabetes (D2d) study. Dietary intake was measured through food frequency questionnaire at baseline. Fasting glucose and fasting insulin were measured at baseline and used to calculate the homeostatic model assessment of insulin resistance (HOMA2-IR). We explored odds of one-year DM development according to low, medium, and high adherence to dietary patterns of nutrient intake using principal covariates regression (PCovR). Results: In the first study, 40% of patients who developed prediabetes received documentation of a prediabetes diagnosis. Nutrition referrals were ordered in 6.6%, metformin prescriptions were made in 4.4%, psychology referrals were ordered in 2.4%, weight management referrals were ordered in 1.7%, and weight loss medications were prescribed in 1.5%. Lower age, female, and higher HbA1c values were frequent predicting variables of documentation for a six-month diagnosis, referral, or prescription. Receiving a clinical diagnosis increased the odds of receiving a referral to weight management and prescriptions for metformin or weight loss medications. In the second study, after accounting for the covariates, age, BMI, sex, education, smoking status, physical activity, race, and treatment group, we found high adherence to a nutrient pattern including intake of animal protein, cholesterol, and arachidonic acid to double the odds of DM development compared to medium adherence (OR 2.02, 95% CI=1.34, 3.04, p=<0.01). Additionally, high intake of total sugars associated with 57% higher odds of DM development compared to moderate intake (OR=1.57, 95% CI=1.02, 2.41, p=0.04). | |
