RESULTS
Our study population comprised 2628 patients with OCSCC, of whom 1915 (72.9%) had private insurance (“Insured”), 561 (21.4%) were insured through Medicaid, and 152 (5.8%) were uninsured. Insured patients were more likely to be male (p=0.03), of older age at presentation (p<0.0001), married (p<0.0001), and White (p<0.0001) (Table 1).
Uni-variable analysis demonstrated that patient characteristics associated with significantly lower odds of receiving definitive treatment included female sex (OR= 0.77; 95% CI 0.66-0.91); unmarried (OR= 0.66; 95% CI 0.53-0.81); separated, divorced, or widowed (OR= 0.67; 95% CI 0.47-0.69); T4b disease (OR= 0.31; 95% CI 0.22-0.44); Medicaid (OR= 0.76; 95% CI 0.63-0.93); and Uninsured (OR= 0.77; 95% CI 0.54-1.09) (Table 2). Figure 1 further demonstrates the unadjusted distribution of definitive and non-definitive treatment types among the Insured, Medicaid and Uninsured treatment categories, illustrating that patients who were Uninsured or on Medicaid are less likely to receive definitive surgical treatment.
Patients with T4a disease during the post-ACA period were more likely to receive definitive treatment (OR=1.22, 95% CI 1.03-1.46) compared to those who received treatment pre-ACA (OR=0.88, 95% CI 0.68-0.97). 37.3% of patients received definitive treatment during the pre-ACA period, which increased to 42.2% of patients in the post-ACA period. For patients insured through Medicaid, while controlling for sex, age, marital status, race, and primary tumor site, those who received treatment pre-ACA were significantly less likely to receive definitive treatment compared to patients with private insurance (OR=0.59, 95% CI 0.46-0.77, p<0.0001). This disparity was no longer statistically significant in the post-ACA period (OR=0.79, 95% CI 0.52-1.21, p=0.52). Controlling for the same variables, uninsured patients who received treatment pre-ACA were also significantly less likely to receive definitive treatment compared to patients with private insurance (OR=0.49, 95% CI 0.32-0.75, p=0.001). Post-ACA, uninsured patients were more likely to receive definitive treatment, although this effect was not statistically significant (OR=1.36, 95% CI 0.56-3.27, P=0.56). Compared to uninsured patients, patients on Medicaid in the post-ACA period were less likely to receive definitive treatment, although this effect was also not statistically significant (OR=0.58, 95% CI 0.24-1.45).
After adjusting for sex, age, year of diagnosis, marital status, race and primary tumor site in the multivariable analysis, patients who were 80 years or older (OR= 0.27; 95% CI 0.08-0.97), with T4b disease (OR=0.32; 95% CI 0.22-0.47), who were unmarried (OR=0.67; 95% CI 0.53-0.85), separated, divorced, or widowed (OR= 0.73; 95% CI 0.59-0.90), who received treatment in the pre-ACA period (OR=0.77; 95% CI 0.64-0.94) and who were on Medicaid (OR= 0.70; 95% CI 0.55-0.88) or uninsured (OR= 0.63; 95% CI 0.43-0.92) were significantly less likely to receive definitive treatment (Table 3). Insurance status was significantly associated with the odds of receiving definitive treatment only among patients with T4a disease (OR=0.69, 95% CI 0.54-0.88 [Medicaid vs. Insured]); and OR=0.65, 95% CI 0.43-0.98 [Uninsured vs Insured]). This disparity was not found for those who presented with T4b disease (OR=0.36; 95% CI 0.12-1.15 [Medicaid vs. Insured]; and OR=0.17, 95% CI 0.03-1.04 [Uninsured vs Insured]). Figure 2 shows the crude distribution of treatment types among insurance categories, stratified by T-stage.