Table 2

Analyses of cumulative estimated exposure to lead and ALS case status in men

Controls N (%)Cases N (%)OR (95% CI)*aOR (95% CI)†
No lag (n=93 508)
 No exposure48 802 (51.67)502 (50.91)1.00 (Ref)1.00 (Ref)
 Ever exposure (µmol/L)‡44 720 (48.33)484 (49.09)1.03 (0.91 to 1.17)1.07 (0.93 to 1.22)
 <23.879 030 (10.73)119 (12.07)1.20 (0.97 to 1.48)1.20 (0.97 to 1.49)
 23.87–102.9010 044 (10.86)111 (11.26)1.02 (0.82 to 1.28)1.04 (0.83 to 1.20)
 >102.9024 746 ()254 (25.76)0.98 (0.84 to 1.15)1.02 (0.87 to 1.20)
 Test for trend1.00 (0.98 to 1.01)1.00 (0.99 to 1.02)
5-year lag
 No exposure53 250 (57.55)558 (56.59)1.00 (Ref)1.00 (Ref)
 Ever exposure (µmol/L)‡39 272 (42.45)428 (43.41)1.05 (0.92 to 1.19)1.08 (0.94 to 1.24)
 <23.8711 337 (12.25)128 (12.98)1.08 (0.89 to 1.32)1.14 (0.93 to 1.39)
 23.87–102.9011 365 (12.28)119 (12.07)1.01 (0.82 to 1.23)1.05 (0.85 to 1.29)
 >102.9016 570 (17.91)181 (18.36)1.05 (0.89 to 1.24)1.06 (0.89 to 1.27)
 Test for trend1.00 (0.99 to 1.01)1.01 (0.98 to 1.04)
10-year lag
 No exposure55 274 (59.74)575 (58.32)1.00 (Ref)1.00 (Ref)
 Ever exposure (µmol/l)‡37 248 (40.26)411 (41.68)1.07 (0.94 to 1.22)1.10 (0.96 to 1.26)
 <23.8711 186 (12.09)127 (12.88)1.10 (0.91 to 1.34)1.14 (0.93 to 1.40)
 23.87–102.9011 161 (12.06)120 (12.17)1.04 (0.86 to 1.27)1.09 (0.88 to 1.34)
 >102.9014 901 (16.11)164 (16.63)1.07 (0.90 to 1.27)1.08 (0.90 to 1.30)
 Test for trend1.01 (0.97 to 1.04)1.01 (0.97 to 1.05)
  • *Controls were individually matched to cases on age and sex.

  • †Models adjusted for SES and residential location.

  • ‡Cumulative estimated exposure = [(level of exposure)*(probability of exposure)/100]*(days employed).

  • ALS, amyotrophic lateral sclerosis; aOR, adjusted OR; SES, socioeconomic status.