Effects of geographic area and socioeconomic status in Taiwan on survival rates of head and neck cancer patients after radiotherapy

Effects of continuity of care on the postradiotherapy survival of working-age patients with oral cavity cancer: A nationwide population-based cohort study in Taiwan

Objectives

Cancer of the oral cavity, a well-known global health concern, remains one of most common causes of cancer mortality. Continuity of care (COC), a measurement of the extent to which an individual patient receives care from a given provider over a specified period of time, can help cancer survivors process their experiences of dealing with the illness and recuperation; however, limited research has focused on the survival rate of working-age patients with oral cancer.

Methods

A total of 14,240 working-age patients (20 <age ≤65 years) with oral cavity cancer treated with radiotherapy (RT) during 2000–2013 were included in this study from a registry of patients with catastrophic illnesses maintained by the Taiwan National Health Insurance Research Database. We evaluated the effects of the Continuity of Care Index (COCI) proposed by Bice and Boxerman, sociodemographic factors, and comorbidities on the survival rate. This study categorized COC into three groups—low (COCI < 0.23), intermediate (COCI = 0.23–0.37), and high (COCI ≥ 0.38)—according to the distribution of scores in our sample. A multivariate Cox proportional hazards regression model was used to determine the demographic factors and comorbidities associated with the survival rate.

Results

Among all the relevant variables, low COCI, male sex, low socioeconomic status, no receipt of prior dental treatment before RT, residence outside northern Taiwan, chemotherapy receipt, and a history of diabetes increased the risk of mortality. Pre-RT dental evaluation and management was significantly associated with reduced post-RT mortality (adjusted hazard ratio [aHR] = 0.767, 95% confidence interval [CI] = 0.729–0.806, p < 0.001). Compared with patients with a high COCI, those with a low COCI exhibited an increased risk of mortality (aHR = 1.170, 95% CI = 1.093–1.252, p < 0.001). The mortality risk in the intermediate COC group was significantly higher than that in the high COC group (aHR = 1.194, 95% CI = 1.127–1.266, p < 0.001). To balance the distribution of the potential risk factors, propensity-score matching was used for the high COC (COCI > 0.38) and non-high COC (COCI ≤ 0.38) groups. After propensity-score matching, the mortality risk in the low and intermediate COC groups was also found to be significantly higher than that in the high COC group (aHR = 1.178, 95% CI = 1.074–1.292, p < 0.001 and aHR = 1.189, 95% CI = 1.107–1.277, p = 0.001, respectively).

Conclusions

In Taiwan, COC and prior dental treatment before RT significantly affected the survival rate of working-age patients with oral cancer. This result merits policymakers’ attention.

Effects of income and residential area on survival of patients with head and neck cancers following radiotherapy: working age individuals in Taiwan

Objectives

The five-year survival rate of head and neck cancer (HNC) after radiotherapy (RT) varies widely from 35% to 89%. Many studies have addressed the effect of socioeconomic status and urban dwelling on the survival of HNC, but a limited number of studies have focused on the survival rate of HNC patients after RT.

Materials and methods

During the period of 2000–2013, 40,985 working age individuals (20 < age < 65 years) with HNC patients treated with RT were included in this study from a registry of patients with catastrophic illnesses maintained by the Taiwan National Health Insurance Research Database (NHIRD).

Results

The cumulative survival rate of HNC following RT in Taiwan was 53.2% (mean follow-up period, 3.75 ± 3.31 years). The combined effects of income and geographic effect on cumulative survival rates were as follows: high income group > medium income group > low income group and northern > central > southern > eastern Taiwan. Patients with moderate income levels had a 36.9% higher risk of mortality as compared with patients with high income levels (hazard ratio (HR) = 1.369; p < 0.001). Patients with low income levels had a 51.4% greater risk of mortality than patients with high income levels (HR = 1.514, p < 0.001).

Conclusion

In Taiwan, income and residential area significantly affected the survival rate of HNC patients receiving RT. The highest income level group had the best survival rate, regardless of the geographic area. The difference in survival between the low and high income groups was still pronounced in more deprived areas.

Socioeconomic factors and survival in patients with non-metastatic head and neck squamous cell carcinoma

The effect of socioeconomic factors on receipt of definitive treatment and survival outcomes in non‐metastatic head and neck squamous cell carcinoma (HNSCC) remains unclear. Eligible patients (n = 37 995) were identified from the United States Surveillance, Epidemiology and End Results (SEER) database between 2007 and 2012. Socioeconomic factors (i.e., median household income, education level, unemployment rate, insurance status, marital status and residence) were included in univariate/multivariate Cox regression analysis; validated factors were used to generate nomograms for cause‐specific survival (CSS) and overall survival (OS), and a prognostic score model for risk stratification. Low‐ and high‐risk groups were compared for all cancer subsites. Impact of race/ethnicity on survival was investigated in each risk group. Marital status, median household income and insurance status were included in the nomograms for CSS and OS, which had higher c‐indexes than the 6th edition TNM staging system (all P < 0.001). Based on three disadvantageous socioeconomic factors (i.e., unmarried status, uninsured status, median household income <US $65 394), the prognostic score model generated four risk subgroups with scores of 0, 1, 2 or 3, which had significantly separated CSS/OS curves (all P < 0.001). Low‐risk patients (score 0–1) were more likely to receive definitive treatment and obtain better CSS/OS than high‐risk patients (score 2–3). Chinese and non‐Hispanic black patients with high‐risk socioeconomic status had best and poorest CSS/OS, respectively. Therefore, marital status, median household income and insurance status have significance for predicting survival outcomes. Low‐risk socioeconomic status and Chinese race/ethnicity confer protective effects in HNSCC.