Abstract 2164: Age at attainment of adult height and risk of primary brain tumors
Authors: Little Rebecca B. , Nabors Louis Burton , Olson Jeffrey J. , Thompson Zachary J. , Madden Melissa H. , LaRocca Renato V. , Forsyth Peter A. , Thompson Reid C. , Egan Kathleen M. 
Published: May 2015

Abstract
Brain tumors represent a small fraction of primary cancers diagnosed each year. However, the disproportionate mortality and morbidity burden associated with brain tumors merits a greater understanding of their cause. Beyond ionizing radiation, few environmental exposures are confirmed to cause brain tumors in humans. A taller stature has been linked to increased risk in several studies. Furthermore, we and others have reported that risk varies with body weight at age 21 though not later in life. These findings suggest a potential role for the myriad of factors involved in adolescent growth with glioma risk. The purpose of this analysis was to further elucidate the relation of height and adolescent growth rate on primary brain tumor risk. The analysis included 1045 glioma cases, 274 meningioma cases and 1242 community controls enrolled in a clinic-based case-control study. In a structured interview participants reported height at age 21 and age at completion of linear growth. Multivariate logistic regression was used to compute odds ratios (OR) and 95% Confidence Intervals (CI) associated with age at attainment of maximum adult height (‘age-HT’) adjusted for age, race, gender, education, and state of residence. Among controls, the median age at height attainment was 17 in men (interdecile range: 15-19 years) and 16 in women (interdecile range: 13-18 years). Age-HT had no association with the risk of meningioma (P= 0.284). However, we observed a statistically significant positive association with the risk of glioma (P&lt;0.001): for each additional year at which adult height was attained risk of glioma was increased 14% in men (OR: 1.14; 95% CI: 1.06, 1.24) and 11% in women (OR: 1.11; 95% CI: 1.04, 1.19). Persons with an age-HT ≥ 19 had nearly twice the risk of glioma (OR: 1.94; 95% CI: 1.36, 2.75) when compared to persons with age-HT ≤ 15, with similar results observed in men (OR: 2.11; 95% CI: 1.24, 3.60) and women (OR: 1.84; 95% CI: 1.07, 3.17), and in high grade (OR: 1.77; 95% CI: 1.18, 2.64) and lower grade (OR: 2.72; 95% CI: 1.59, 4.65) tumors. Among controls, adult height and age-HT were uncorrelated both in men (Pearson r = -0.03) and in women (Pearson r = 0.09). When we considered the association of age-HT by tertile of adult height (defined by gender), a statistically significant positive association was observed with increasing increment in age-HT in the lowest (OR: 1.16; P = 0.003) and middle tertile (OR: 1.18; P &lt; 0.001), whereas no association was observed in the highest (OR: 1.01; P = 0.881) tertile of adult height. To our knowledge, this is the first report linking age at completion of linear growth with subsequent risk of glioma. A postulated mechanism is that a prolonged growth phase may increase exposure to growth factors that enhance glioma risk. Null findings in those attaining a tall stature, if not due to chance, suggest complex interactions with the timing and intensity of risk-promoting exposures. These findings warrant further study.
Citation Format: Rebecca B. Little, Louis Burton Nabors, Jeffrey J. Olson, Zachary J. Thompson, Melissa H. Madden, Renato V. LaRocca, Peter A. Forsyth, Reid C. Thompson, Kathleen M. Egan. Age at attainment of adult height and risk of primary brain tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2164. doi:10.1158/1538-7445.AM2014-2164