Table 4.

Association of combinations of metabolic health defined by HOMA-IR and BMI (normal, overweight, obese) with risk of postmenopausal breast cancer, Women's Health Initiative CVD Biomarkers Sub-Cohort (n = 20,569)

(n cases 829; n noncases 13,955)
Low HOMA-IRa/normal weight1342,6801.00Ref.
High HOMA-IRb/normal weight911,9190.950.72–1.25
Low HOMA-IR/overweight326500.970.64–1.46
High HOMA-IR/overweight266500.850.55–1.34
Low HOMA-IR/obese1522,7961.170.91–1.49
High HOMA-IR/obese3945,2601.571.26–1.95
  • NOTE: 41 cases and 385 noncases were missing HOMA-IR. Total n is reduced because the 2nd quartile was excluded in the analysis. Adjusted for age (continuous), smoking status (never, former, current), pack-years of smoking (continuous), alcohol intake (drinks/week – continuous), physical activity (MET-h/wk), age at first birth (<20, 20–29, ≥30, missing), age at menarche (<12, 12, 13, ≥14), age at menopause (<45, 45–54, ≥55, missing), oral contraceptives (never, ever), hormone therapy (never, ever), parous/nulliparous, family history of breast cancer in first-degree relative (no, yes), history of breast biopsy (no, yes), breastfed for more than 6 months (no, yes), education (less than high school grad, high school grad/some college, college grad, post-college), ethnicity (white, black, other), allocation to the OS or specific arm of clinical trials.

  • aLow HOMA-IR defined as lowest quartile.

  • bHigh HOMA-IR defined as quartiles 3 and 4.