2016 Writing Contest Undergraduate Winner: The Relationship Between Medication Adherence and Total Healthcare Expenditures by Race/Ethnicity in Patients with Diabetes in Hawai'i.

Diabetes is a costly, chronic disease that is becoming increasingly prevalent worldwide. Studies show that Native Hawaiians suffer from higher rates of diabetes and lower rates of medication adherence compared to Caucasians and Japanese. This study compared total annual healthcare expenditures of patients with diabetes in Hawai'i by race and ethnicity and determined whether any existing differences persisted after controlling for medication adherence and demographic factors. The study population consisted of 30,445 individuals, using administrative claims data from a large health plan in Hawai'i. Filipinos, Native Hawaiians, and Other Pacific Islanders had significantly lower medication adherence rates compared to other groups. These ethnic groups also had the lowest median healthcare costs. In contrast, Caucasians had one of the highest medication adherence rates coupled with the highest median annual healthcare expenditures at $5,132. Generalized linear regression models showed that after controlling for demographic factors and medication adherence, Japanese (RR=0.86, 95%CI [0.78, 0.94]), Chinese (RR=0.83, 95%CI [0.73, 0.95]), Filipinos (RR=0.74, 95%CI [0.67, 0.82]), and Native Hawaiians (RR=0.74, 95%CI [0.67, 0.82]) had significantly lower total healthcare costs compared to Caucasians. Costs for Other Pacific Islanders were not significantly different from those of Caucasians. This study provides evidence that total health-related cost is associated with a multitude of factors that further research may reveal.