Association of immunoglobulin E levels with glioma risk and survival

Background Previous epidemiologic studies have reported an association of serum immunoglobulin E (IgE) levels with reduced glioma risk, but the association between IgE and glioma prognosis has not been characterized. This study aimed to examine how sex, tumor subtype, and IgE class modulate the association of serum IgE levels with glioma risk and survival. Methods We conducted a case-control study using participants from the University of California, San Francisco Adult Glioma Study (1997-2010). Serum IgE levels for total, respiratory and food allergy were measured in adults diagnosed with glioma (n = 1319) and cancer-free controls (n = 1139) matched based on age, sex, and race and ethnicity. Logistic regression was adjusted for patient demographics to assess the association between IgE levels and glioma risk. Multivariable Cox regression adjusted for patient-specific and tumor-specific factors compared survival between the elevated and normal IgE groups. All statistical tests were 2-sided. Results Elevated total IgE was associated with reduced risk of IDH-wildtype (RR = 0.78, 95% CI: 0.71-0.86) and IDH-mutant glioma (RR = 0.73, 95% CI: 0.63-0.85). In multivariable Cox regression, positive respiratory IgE was associated with improved survival for IDH-wildtype glioma (RR = 0.79, 95% CI: 0.67-0.93). The reduction in mortality risk was significant in females only (RR = 0.75, 95% CI: 0.57-0.98) with an improvement in median survival of 6.9 months (P<.001). Conclusion Elevated serum IgE was associated with improved prognosis for IDH-wildtype glioma, with a more pronounced protective effect in females than males, which has implications for the future study of IgE-based immunotherapies for glioma.