Temporal trends and demographic patterns in Hodgkin and non-Hodgkin lymphoma mortality among u.s. adults: A CDC wonder study

Abstract BACKGROUND: Hodgkin Lymphoma (HL) and non-Hodgkin lymphoma (NHL) are distinct malignancies that affect the lymphatic system, exhibiting varying clinical behaviors and outcomes. Understanding their mortality trends provides significant insights into disease burden and helps identify treatment gaps. This study aims to analyze and compare mortality trends in the U.S over the past 2 decades, utilizing the CDC-WONDER data. METHODS: We conducted a retrospective population-based study using the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research system (CDC WONDER) to analyze deaths related to HL and NHL in the US from 1999 to 2020. ICD codes C81.0-81.9 for HL and C82.0-85.9 for NHL were used to extract data. Crude mortality rates (CMR) and Age-adjusted mortality rates (AAMR) per 100,000, and trends were assessed using Joinpoint regression to estimate annual and average annual percent changes (APC, AAPC). Pairwise comparison was also performed using the same program to explore whether there were statistically significant differences in AAPCs of HL and NHL-related mortality. A p-value of <0.05 was considered to be significant. RESULTS: From 1999 to 2020, a total of 35,319 deaths were attributed to Hodgkin lymphoma (HL), while non-Hodgkin lymphoma (NHL) accounted for a substantially higher number of deaths (n = 557,741). Mortality trends for both HL and NHL showed a statistically significant decline over time. The average annual percent change (AAPC) for HL was -2.79% (95% CI: -3.04 to -2.54, p < 0.05), and for NHL, -2.10% (95% CI: -2.28 to -1.93, p < 0.05). Pairwise analysis confirmed a significant overall AAPC difference (p = 0.000667). In HL, males experienced higher mortality than females (n = 20,244 vs. 15,075), but the decline in mortality was steeper among females (AAPC: -3.06%, 95% CI: -3.42 to -2.71) than males (AAPC: -2.50%, 95% CI: -2.82 to -2.18), both with p < 0.05. Similarly, for NHL, mortality was higher in males (n = 307,009) compared to females (n = 250,732), although females had a greater rate of decline (AAPC: -2.45%, 95% CI: -2.74 to -2.16) compared to males (AAPC: -1.81%, 95% CI: -2.09 to -1.53), both with p < 0.000001. By race and ethnicity, the White population had the highest number of HL-related deaths (n = 28,205), followed by African Americans (n = 3,260) and Hispanics (n = 3,098). Whites also showed the most pronounced decline in HL mortality (AAPC: -2.71%, 95% CI: -3.01 to -2.40, p < 0.05). For NHL, mortality was highest among Whites (n = 469,467), followed by African Americans (n = 38,319) and Hispanics (n = 33,558), with corresponding AAPCs of -2.00% (95% CI: -2.20 to -1.81), -2.06% (95% CI: -2.60 to -1.52), and -1.55% (95% CI: -1.82 to -1.28), respectively (all p < 0.05). Geographically, both urban and rural populations experienced significant declines in HL mortality, with a more pronounced decrease in urban areas (AAPC: -2.77%, 95% CI: -3.05 to -2.50) compared to rural areas (AAPC: -1.98%, 95% CI: -2.48 to -1.48), both with p < 0.05. Similar patterns were observed for NHL, with urban populations showing a greater decline (AAPC: -2.20%, 95% CI: -2.42 to -1.99, p < 0.000001) than rural populations (AAPC: -1.51%, 95% CI: -1.92 to -1.10, p < 0.05). All four U.S. Census regions demonstrated significant reductions in HL mortality. The Northeast had the steepest decline (AAPC: -3.15%, 95% CI: -3.66 to -2.63, p < 0.000001), followed by the Midwest (-2.88%), South (-2.52%), and West (-2.51%). For NHL, mortality also declined across all regions, with the Northeast again showing the greatest decrease (AAPC: -2.42%, 95% CI: -2.74 to -2.11), followed by the West (-2.11%), South (-2.00%), and Midwest (-1.99%). CONCLUSION: Over the last two decades, mortality due to HL and NHL has undergone a remarkable change, with both conditions demonstrating a negative trend. This decline reflects the importance of early detection, treatment modalities, and supportive care. However, disparities remain, underscoring the need for targeted public health strategies and equitable access to care to sustain and enhance these improvements.