Table 1

Summary of prospective studies included in meta-analysis, separately performed for total, free or bioavailable testosterone, and cardiovascular disease in healthy men

Study, year of publication (ref.)Follow-up, yearsOutcomeEvents/progression of diseaseOriginal coefficient (SE)*RR (95% CI) after re-expression
IncrementBSE
Total testosterone
 Cauley et al2 †† ‡‡ ¶¶6–8MI163U33/L330.1130.2571.07 (0.79 to 1.44)
 Phillips et al3 7MI961 ng/ml−0.0560.0760.90 (0.68 to 1.19)
 Yarnell et al4 †† ¶¶5IHD153SD0.1040.0961.11 (0.92 to 1.34)
 Hautanen et al5 ¶¶5CVD62nmol/l0.0100.0231.07 (0.80 to 1.43)
 Price et al6 ††5AS40SD−0.2880.3100.75 (0.41 to 1.38)
 Hak et al7 ††7AS28U33/L33−0.9160.5870.84 (0.67 to 1.05)
 Muller et al8 4AS195SD−0.0220.0160.98 (0.95 to 1.01)
 Eller et al9 ** ¶¶4AS95SD−0.3130.1790.73 (0.51 to 1.04)
 Arnlöv et al10 § ¶¶10CVD386SD−0.0100.0570.99 (0.88 to 1.10)
 Hougaku et al11 ** ***11.8AS2061.08 (0.91 to 1.27)
 Tivesten et al12 ** ¶¶ ***3AS3131.06 (0.94 to 1.19)
 Shores et al13 § §§4.3M13911.4 nmol/L−0.5190.1980.75 (0.60 to 0.93)
 Araujo et al14 ¶¶15.3IHD101SD−0.0940.1080.91 (0.74 to 1.12)
15.3M395SD0.0200.0521.02 (0.92 to 1.13)
 Khaw et al15 ††7CVD293SD−0.2360.1060.79 (0.64 to 0.97)
7M825SD−0.2360.0710.79 (0.69 to 0.91)
 Laughlin et al16 § §§11.8M538L25/U250.3650.1260.75 (0.61 to 0.92)
 Lehtonen et al17 § §§10M681 nmol/l−0.0510.0240.72 (0.53 to 0.97)
 Tivesten et al18 §4.5M383SD−0.2480.0360.78 (0.73 to 0.84)
 Yeap et al19 § ‡‡ §§3.5S119L25/U750.6880.2070.68 (0.54 to 0.85)
Free testosterone
 Cauley et al2 †† ‡‡ ¶¶6–8MI163U33/L330.0390.3731.02 (0.67 to 1.57)
 Price et al6 ††5AS40SD0.1910.3021.10 (0.61 to 1.99)
 Muller et al8 4AS195SD−0.0470.0240.95 (0.91 to 1.00)
 Tivesten et al12 ** ¶¶ ***3AS3131.04 (0.93 to 1.16)
 Araujo et al14 ¶¶15.3IHD101SD−0.2230.1110.80 (0.64 to 0.99)
15.3M395SD0.0680.0571.07 (0.96 to 1.20)
 Tivesten et al18 §4.5M383SD−0.2610.0360.77 (0.72 to 0.83)
 Yeap et al19 § ‡‡ §§3.5S119L25/U750.5250.1960.73 (0.59 to 0.92)
Bioavailable testosterone
 Hak et al7 ††7AS28U33/L33−1.6091.0440.78 (0.56 to 1.07)
 Maggio et al20 § ‡‡6M126L25/U750.3920.2590.54 (0.24 to 1.20)
 Laughlin et al16 § §§11.8M538L25/U250.3360.1100.74 (0.60 to 0.91)
  • * Coefficient per increment (specified difference in testosterone level) derived from the original article before re-expression—for example, a coefficient or 0.11 per U33/L33 is a coefficient of 0.11 for subjects with the highest 33% versus the lowest 33% of testosterone levels.

  • Nested case–control study.

  • Longitudinal data retrieved by existing database.

  • § Cox regression analyses.

  • Poisson regression analyses.

  • ** Linear regression analyses.

  • †† Logistic regression analyses.

  • ‡‡ Testosterone data of reference populations16 18 30 was used for re-expression (see text).

  • §§ The mean SD of included studies was used for re-expression (see text).

  • ¶¶ Study population younger than 70 years of age.

  • *** RR (95% CI) obtained by direct correspondence with authors.

  • AS, atherosclerosis measurement; CVD, cardiovascular disease; IHD, ischaemic heart disease; M, mortality; MI, myocardial infarction; S, stroke or transient ischaemic attack.