PURPOSE: To study the impact of insurance status on out-of-pocket (OOP) expenditure in Stroke patients.
METHODS: 2005-2009 Medical Expenditure Panel Survey (MEPS) data was used for the study. A two-part model was used consisting of logistic regression to estimate the odds of OOP expenditure in stroke patients and an ordinary least square (OLS) regression model to estimate the expenditure in those stroke patients who had any OOP expense during the study period. The dependent variables in the two-part model were regressed on age, gender, race, insurance status, employment, income, US region, survey year and comorbidities such as hypertension, Diabetes mellitus and Coronary heart disease. The comorbidities were identified based on the relevant ICD-9-CM codes in the medical conditions file, whereas all other variables were taken from the household component file of the MEPS data. The data was analyzed using the survey data commands in STATA SE version 13.
RESULT: The logistic regression shows that middle-income patients had 4.75 times and high-income patients had 3.9 times higher odds than poor patients of incurring OOP expense. Age (OR 1.02) and history of Diabetes mellitus (OR 3.3) increased the odds of OOP expenditure. The OLS regression showed that as compared to privately insured, the OOP expenditures was 19.8% lower in ‘Medicare only’, 154% lower in ‘Medicaid only’ and 112% lower in ‘Medicare and Medicaid insurance’. The OOP expenditure was 37.7% higher in middle-income and 48.8% higher in high-income patients. Non-Hispanic Blacks had 32.9% lower OOP expenditure than non-Hispanic Whites. The OLS regression also showed that OOP expenditure increased with age by 0.8% and history of Diabetes mellitus by 43.1%. There was no multicollinearity in the OLS regression. There was omitted variable bias in the OLS regression. The independent variables explained 22% of the variation in expenditure in the OLS regression.
CONCLUSION: Middle-income and high-income patients had higher odds of having an OOP expense and higher OOP expenditure. The study shows that non-Hispanic Blacks and patients on some government insurance have lower OOP expenditure. Age and history of Diabetes mellitus increases both the odds of having any OOP expenditure and higher OOP expenses once a patient incurs them.
