Abstract
OBJECTIVES: This study assessed the excess healthcare expenditures and factors associated with it among community-dwelling adults with thyroid cancer compared to non-cancer controls in the United States (US). METHODS: We adopted a retrospective, cross-sectional, matched case-control study design by pooling Medical Expenditure Panel Survey (MEPS) data (2002-2012). The eligible study sample comprised of adults (age ≥ 21 years), who were alive during the calendar year and reported positive healthcare expenditure. We identified adults with thyroid cancer (cases) with Clinical Classification System code of "36". The control group consisted of adults who did not have any form of cancer. The case and control groups were matched on propensity score generated based on age, gender, race/ethnicity, smoking status and Body Mass Index. We conducted a series of Ordinary Least Square (OLS) regressions on log-transformed expenditures to elucidate the influence of different factors on healthcare expenditures (total, emergency room, inpatient, prescription, outpatient, home healthcare and other) among adults with thyroid cancer. We used semi-logarithmic equation (e(β-1) to calculate the percent difference in costs between cases and controls. RESULTS: The yearly average total healthcare expenditures among adults with thyroid cancer was significantly higher compared to propensity score matched controls ($9,734 vs. $6,329, p<0.001). Similar observations were found in terms of inpatient ($3,164 vs. 2,314, p<0.05), outpatient ($4,208 vs. 1,663, p< 0.001), and prescription expenditures ($1,613 vs. 1,468, p< 0.001). Functional status as well as comorbid conditions were significantly associated with excess expenditures among the case group compared to matched controls. For example, difference in total healthcare expenditures decreased from 182% to 90% when functional and health status and comorbidities were added to the OLS regressions. CONCLUSIONS: Our findings suggest that in this nationally representative sample of adults with thyroid cancer, functional and health status as well as comorbidities significantly influence the excess expenditures.