To investigate the association between allergic conditions (e.g., hay fever, asthma) and the risk of brain tumors, including glioma, meningioma, and acoustic neuroma.
Key Findings:
History of allergy was associated with a decreased risk of brain tumors (OR 0.78, 95% CI 0.71–0.86).
Case-control studies showed a reduced risk (OR 0.71, 95% CI 0.63–0.79), while cohort studies showed no significant trend (OR 1.00, 95% CI 0.85–1.19).
No significant publication bias was detected, but the lack of significant findings in cohort studies suggests caution in interpretation.
Interpretation:
The findings suggest that individuals with a history of allergies may have a lower risk of developing brain tumors, although results vary between study designs, indicating the need for further investigation.
Limitations:
Only observational studies were included, which may limit causal inferences.
Heterogeneity among studies could affect the robustness of the findings.
Potential biases in study designs and reporting may influence results, and confounding factors should be considered.
Conclusion:
The study supports an inverse association between allergy history and brain tumor risk, warranting further investigation into the underlying mechanisms, particularly focusing on specific allergic conditions.
