Table 3

Sex hormone-binding globulin and endogenous sex hormones by treatment group at week 4 and week 8 in women
Week 4 Week 8
Value (95% confidence interval) Value (95% confidence interval)
Caffeinated Decaffeinated No Coffee Caffeinated Decaffeinated No Coffee
Coffee Coffee Coffee Coffee Coffee
(N = 10) (N = 9) (N = 9) (N = 10) (N = 9) (N = 9)
SHBG (nmol/L)
Geometric means 43.8 (35.2, 54.5) 52.8 (42.5, 65.5) 38.2 (30.7, 47.6) 44.2 (37.3, 52.4) 45.8 (38.7, 54.1) 44.2 (37.3, 52.4)
Difference in CFB (%) 14.6 (−16.2, 56.7) 38.0 (1.5, 87.7) a Reference −0.0 (−21.6, 27.4) 3.6 (−18.4, 31.5) Reference
Testosterone (ng/dL)
Geometric means 51.3 (33.5, 78.6) 39.0 (24.8, 61.4) 98.3 (62.3, 155.2) 35.1 (26.2, 47.0) 32.4 (23.8, 44.2) 37.3 (27.3, 51.0)
Difference in CFB (%) −47.8 (−72.1, -2.3) a −60.3 (−79.3, -24.0) b Reference −5.9 (−38.7, 44.3) −13.1 (−44.3, 35.5) Reference
Free testosterone (ng/dL)
Geometric means 0.6 (0.3, 1.0) 0.4 (0.2, 0.7) 1.2 (0.7, 2.1) 0.4 (0.3, 0.6) 0.3 (0.2, 0.5) 0.4 (0.3, 0.6)
Difference in CFB (%) −51.1 (−78.7, 12.0) −67.8 (−86.0, -26.2) b Reference −6.0 (−47.5, 68.5) −13.3 (−51.6, 55.4) Reference
Estradiol (pg/mL)
Geometric means 37.9 (26.5, 54.2) 42.6 (29.0, 62.3) 42.9 (28.7, 64.1) 41.8 (24.8, 70.6) 39.7 (22.7, 69.4) 40.6 (23.3, 70.6)
Difference in CFB (%) −11.8 (−48.4, 50.8) −0.9 (−43.2, 73.2) Reference 3.2 (−51.7, 120.5) −2.1 (−55.8, 116.6) Reference
Free estradiol (pg/mL)
Geometric means 0.6 (0.4, 0.9) 0.6 (0.4, 0.9) 0.7 (0.5, 1.1) 0.7 (0.4, 1.1) 0.6 (0.3, 1.0) 0.6 (0.4, 1.1)
Difference in CFB (%) −19.3 (−56.1, 48.3) −13.4 (−53.5, 61.3) Reference 2.9 (−52.2, 121.6) −5.2 (−56.8, 108.2) Reference
Testosterone : Estradiol
Geometric means 1.4 (0.8, 2.3) 1.0 (0.6, 1.7) 2.1 (1.2, 3.8) 0.8 (0.5, 1.5) 0.8 (0.4, 1.5) 0.9 (0.5, 1.7)
Difference in CFB (%) −36.0 (−71.0, 41.4) −54.1 (−79.6, 3.3) Reference −9.9 (−61.7, 111.9) −9.6 (−62.6, 118.3) Reference
DHEAs (ng/mL)
Geometric means 113.8 (101.0, 128.1) 101.7 (89.6, 115.5) 100.0 (87.5, 114.4) 111.7 (101.0, 123.6) 102.9 (92.3, 114.6) 120.4 (108.2, 134.1)
Difference in CFB (%) 13.7 (−4.9, 36.0) 1.7 (−15.6, 22.5) Reference −7.2 (−19.9, 7.4) −14.6 (−26.7, -0.4) Reference

SHBG, sex hormone-binding globulin; CFB, change from baseline; DHEAs, dehydroepiandrosterone sulfate.

Geometric mean as the dependent variable with treatment as a main effect, and baseline log value (grand mean centered) and age (grand mean centered) as covariates.

Difference in change from baseline compared to No Coffee (i.e., ratio of ratios) adjusted for the above covariates.

a p < 0.05 compared to No Coffee.

b p < 0.01 compared to No Coffee.

Wedick et al.

Wedick et al. Nutrition Journal 2012 11:86   doi:10.1186/1475-2891-11-86

Open Data