Socio-Economic Inequalities in Dental Care Utilization Among the U.S. Population: A Study of Trends From 2010 to 2019

Abstract

Abstract Objectives for aim1 a and aim1 b: Medicaid expansion under the Affordable Care Act (ACA) has tremendously improved the utilization of dental services among children under 19 years of age.9 Despite this progress, there are no dental requirements for adults, and adult coverage remains at the discretion of individual states.14 The concept of health disparities was first introduced in HP 2010 as an overarching goal. However, 69% of the HP 2010’s health disparities-related objectives did not achieve significant improvements.3 In this study, we assessed dental care utilization among U.S. adults (≥18 years) in general (aim1 a) and U.S. adults (≥18 years) who cannot afford dental treatment (aim1 b) using the National Health Information Survey (NHIS) data from 2010 to 2019. Methods for aim1a and aim1b: This analysis included 316,806 respondents. Eight socioeconomic indicators (SEI) were analyzed to assess their associations with past-year utilization of dental care. The Slope Index of Inequality (SII) and Relative Index of Inequality (RII) were used to measure inequality for ordinal variables. Risk difference and risk ratio were calculated to measure inequality for variables that lack natural ordering. Logistic regression was used to assess trends. Results: Aim1a

A significant increase in last year’s dental visit was observed from 2010 to 2019 (60.56 % to 65.28 %; p-trend<.001). Within the pooled analyses, lower odds of visiting the dentist were seen among respondents who were uninsured (OR:0.33, 95%CI:0.32-0.34) or who have public insurance (OR:0.76, 95%CI:0.73-0.78) compared to respondents with private insurance. Respondents between 200%-399% FPL (OR:1.48, 95%CI:1.42-1.53),or more than 400% FPL (OR:2.78, 95%CI:2.66-2.90) had lower odds of visiting the dentist compared to respondent with annual family income less than 100% FPL. Inequality decreased on both the absolute and relative scales for all the socio-economic indicators. Aim1b Among the respondents, a significant increase in last year’s dental visit was observed from 2010 (35.39 ) to 2019 (43.11%) (p-trend<0.001). Within the pooled analyses, the adjusted odds of visiting the dentist were lower among uninsured (OR:0.41, 95%CI:0.38-0.44) or adults with public health insurance (OR:0.87, 95%CI:0.80-0.95) compared to respondents with private health insurance. Adults with annual family income between 200%-399% FPL (OR:1.36, 95%CI:1.25- 1.49), or more than 400% FPL (OR:2.25, 95%CI:2.02-2.51) had higher odds of visiting the dentist compared to adults with annual family income less than 100% FPL. During the study period, measured inequalities by annual family income increased on the absolute scale (2010 SII:0.28 - 2019 SII:0.34). Furthermore, the absolute inequality didn’t change for people who were uninsured or who had a public insurance compared to people who had private insurance. Conclusion:

Although dental care utilization increased between 2010 and 2019, absolute inequality increased by annual family income for people who cannot afford dental treatment. Closing the gap in dental care utilization by targeted intervention can help in achieving Healthy People goals for equitable oral health.