Circulating lipids and glioma risk: results from the UK Biobank, Nurses' Health Study, and Health Professionals Follow-Up Study.

Evidence is mixed on whether cholesterol plays a role in the pathogenesis of glioma. We explored the associations between circulating lipids and glioma risk in three prospective cohorts. Using prospective data from the UK Biobank, we examined the associations of total cholesterol (TC), high- and low-density lipoprotein cholesterol (HDL-C, LDL-C), and triglycerides (TG) with glioma risk in multivariable (MV)-adjusted Cox proportional hazards models. Within the Nurses’ Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS), we carried out a matched, nested case–control study to examine these same associations. In the UK Biobank, 490 gliomas accrued over 2,358,964 person-years. TC was not significantly associated with glioma risk (MV HR = 1.20, 95% CI 0.89–1.61 for highest quartile vs. lowest, p-trend = 0.24). In 4-year lagged analyses (n = 229), higher TC was associated with significantly higher risk of glioma in men (MV HR = 2.26, 95% CI 1.32–3.89, p-trend = 0.002) but not women (MV HR = 1.28, 95% CI 0.61–2.68, p-trend = 0.72); similar findings emerged for HDL-C and, to a lesser extent, LDL-C. In the NHS/HPFS, no significant associations were found between cholesterol and glioma risk. No significant associations were identified for TG. In the UK Biobank, higher prediagnostic TC and HDL-C levels were associated with higher risk of glioma in 4-year lagged analyses, but not in non-lagged analyses, in men only. These findings merit further investigation, given that there are few risk factors and no reliable biomarkers of risk identified for glioma.