Table 1.

Selected characteristics [mean (SD) or percentage] of IWHS subjects (N = 22,601) by self-reported allergic status at the fourth follow-up questionnaire in 1997

Allergy
CharacteristicNo (N = 15,449)Yes (N = 7,152)P valuea
Mean age at 1997 follow-up (SD; years)72.23 (4.14)72.08 (4.16)0.01
Mean age at myeloid cancer diagnosis (SD; years)79.99 (4.88)80.42 (4.29)0.58
Mean age at lymphoid cancer diagnosis (SD; years)79.32 (5.17)78.76 (5.35)0.30
Education (>high school)b40.1945.50<0.0001
BMI ≥30 kg/m2c22.7126.69<0.0001
Cigarette smoking status (yes)c6.015.970.90
Rural residenceb,d29.7524.57<0.0001
Hormone replacement therapy use (yes)c20.6826.75<0.0001
Multivitamin use (yes)b31.7637.16<0.0001
  • aP values from general linear model or χ2 test for continuous and categorical variables, respectively.

  • bMeasured in 1986 baseline questionnaire.

  • cMeasured in 1997 follow-up questionnaire, when allergic conditions were first queried. Notably, results were nearly identical upon adjustment for BMI, and smoking status and duration at baseline.

  • dWhere rural was defined as living on a farm and a rural area but not a farm, and urban was defined as any town or city.