Table 3.

Estimated risk of meningioma with categories of lead exposure by ALAD G177C genotype in the NCI Brain Tumor Study, 1994-1998

MeningiomaGenotyped individuals
ALAD1 individuals
ALAD2 individuals*
Cases/controls (n)OR (95% CI)Cases/controls (n)OR (95% CI)Cases/controls (n)OR (95% CI)
Cumulative exposure to lead, medium to high confidence exposures only (μg/m3-y)
    0111/2981.0 (reference)89/2441.0 (reference)22/531.0 (reference)
    1-4917/1040.9 (0.5-1.7)14/890.9 (0.4-1.8)4/191.2 (0.2-6.2)
    50-999/341.8 (0.7-4.7)5/251.3 (0.4-4.1)4/56.7 (0.8-55.2)
    ≥1008/391.2 (0.5-3.1)4/360.6 (0.2-2.1)5/318.8 (1.6-221.5)
β, P§0.003, 0.10.001, 0.60.006, 0.1
OR for a 50 μg/m3-y increase in cumulative exposure to lead1.161.071.34
Average exposure to lead (μg/m3)
    0110/2901.0 (reference)88/2381.0 (reference)22/521.0 (reference)
    1-419/1020.8 (0.4-1.5)16/810.9 (0.5-1.8)3/210.7 (0.1-3.3)
    5-915/930.9 (0.4-1.7)9/840.5 (0.2-1.3)6/99.4 (1.3-67.9)
    ≥107/201.7 (0.6-4.7)3/170.9 (0.2-3.4)4/311.3 (1.1-113.9)
β, P0.02, 0.5−0.04, 0.40.23, 0.02
OR for a 5 μg/m3 increase in average exposure to lead1.120.823.12
Highest exposure to lead (μg/m3)
    <10117/3111.0 (reference)95/2541.0 (reference)22/571.0 (reference)
    10-2912/680.6 (0.3-1.3)7/570.4 (0.2-1.1)5/111.8 (0.4-7.8)
    30-499/610.8 (0.3-1.7)7/550.6 (0.3-1.6)2/62.1 (0.3-16.6)
    ≥5013/651.0 (0.5-2.2)7/540.6 (0.2-1.7)6/114.0 (0.8-20.8)
  • * Includes ALAD1-2 heterozygotes and ALAD2-2 homozygotes.

  • Models using exposure categories were adjusted for age and sex only.

  • Number of exposed cases or controls is less than five.

  • § Models of underlying continuous variables were adjusted for matching factors: age, sex, race, hospital, and distance of residence from hospital.

  • Estimated airborne lead concentration for the job with highest exposure in the patient's work history.