Table 5.

Difference in mean hormone concentrations by age and race/ethnicity, comparing NHANES 1988–1991 to 1999–2004.

		1988–1991		1999–2004
	Age (years)	Meana, b	95% CIc	Meana, b	95% CIc	Difference	P-value
White
Testosterone (ng/ml)	20–44	5.51	5.26, 5.76	5.20	4.90, 5.51	−0.31	0.06
	45–69	5.19	4.93, 5.45	5.35	5.04, 5.67	0.17	0.30
	≥ 70	5.21	4.70, 5.72	5.25	4.66, 5.84	0.04	0.85
Free testosterone (ng/ml)	20–44	0.102	0.096, 0.109	0.102	0.096, 0.108	0	0.93
	45–69	0.098	0.088, 0.110	0.095	0.087, 0.104	−0.003	0.61
	≥ 70	0.084	0.072, 0.097	0.070	0.057, 0.087	−0.014	0.09
SHBG (nmol/L)	20–44	36.07	33.56, 38.77	30.94	28.54, 33.53	−5.14	<0.01
	45–69	32.47	29.87, 35.28	35.29	31.99, 38.93	2.83	0.05
	≥ 70	36.12	30.40, 42.90	39.16	33.11, 46.32	3.04	0.13
3α-diol-G (ng/ml)	20–44	12.57	11.59, 13.64	9.68	8.88, 10.55	−2.89	<0.01
	45–69	11.57	10.26, 13.06	10.60	9.59, 11.71	−0.97	0.17
	≥ 70	12.32	10.09, 15.05	10.79	9.03, 12.89	−1.53	0.08
Estradiol (pg/ml)	20–44	35.14	33.11, 37.29	28.65	26.31, 31.19	−6.49	<0.01
	45–69	35.09	31.92, 38.58	29.37	26.96, 32.00	−5.72	<0.01
	≥ 70	38.46	34.02, 43.48	28.96	24.48, 34.27	−9.50	<0.01
Black
Testosterone (ng/ml)	20–44	5.42	4.94, 5.91	5.97	5.55, 6.39	0.55	0.06
	45–69	5.37	4.82, 5.92	5.74	5.07, 6.42	0.38	0.37
	≥ 70	4.41	3.55, 5.28	6.26	4.14, 8.39	1.85	0.09
Free testosterone (ng/ml)	20–44	0.098	0.089, 0.107	0.112	0.101, 0.124	0.014	0.03
	45–69	0.102	0.090, 0.115	0.101	0.088, 0.115	−0.001	0.87
	≥ 70	0.069	0.048, 0.099	0.104	0.078, 0.137	0.035	0.05
SHBG (nmol/L)	20–44	35.21	32.02, 38.72	34.94	31.69, 38.52	−0.27	0.88
	45–69	33.08	29.71, 36.84	34.34	29.36, 40.17	1.26	0.64
	≥ 70	30.46	25.69, 36.11	29.98	23.81, 37.75	−0.48	0.88
3α-diol-G (ng/ml)	20–44	11.16	9.99, 12.46	10.16	9.24, 11.17	−1.00	0.15
	45–69	10.54	8.19, 13.55	10.00	8.79, 11.37	−0.54	0.68
	≥ 70	9.77	6.91, 13.82	13.97	8.36, 23.36	4.20	0.19
Estradiol (pg/ml)	20–44	40.67	38.30, 43.18	38.97	34.31, 44.25	−1.70	0.54
	45–69	38.75	35.52, 42.26	38.03	31.58, 45.78	−0.72	0.84
	≥ 70	39.53	32.90, 47.49	44.41	31.62, 62.38	4.89	0.51
Mexican American
Testosterone (ng/ml)	20–44	5.36	5.12, 5.60	5.07	4.65, 5.50	−0.28	0.16
	45–69	5.15	4.80, 5.49	5.16	4.44, 5.88	0.01	0.97
	≥ 70	5.52	4.51, 6.52	5.80	5.00, 6.60	0.28	0.62
Free testosterone (ng/ml)	20–44	0.104	0.099, 0.109	0.100	0.091, 0.109	−0.004	0.40
	45–69	0.094	0.086, 0.103	0.086	0.073, 0.101	−0.009	0.26
	≥ 70	0.104	0.086, 0.124	0.100	0.085, 0.117	−0.003	0.72
SHBG (nmol/L)	20–44	32.76	29.94, 35.85	32.54	29.20, 36.25	−0.23	0.90
	45–69	33.98	31.41, 36.77	34.94	29.32, 41.65	0.96	0.75
	≥ 70	32.33	26.43, 39.54	35.99	29.45, 43.98	3.66	0.35
3α-diol-G (ng/ml)	20–44	10.84	9.63, 12.21	9.57	8.54, 10.72	−1.27	0.09
	45–69	9.88	8.52, 11.45	9.24	8.05, 10.60	−0.64	0.48
	≥ 70	14.87	9.71, 22.77	12.07	10.17, 14.33	−2.79	0.33
Estradiol (pg/ml)	20–44	33.38	30.92, 36.03	25.88	23.47, 28.52	−7.50	<0.01
	45–69	32.31	28.69, 36.38	26.21	22.83, 30.10	−6.10	0.02
	≥ 70	37.93	31.13, 46.21	28.61	23.38, 35.02	−9.32	0.01

^aadjusted for age (1 year intervals), BMI, waist circumference, smoking, and alcohol use

^bmeans for free testosterone, SHBG, 3α-diol-G, and estradiol are geometric means

^cCI – confidence interval