Author + information
- Received February 26, 2011
- Accepted July 7, 2011
- Published online October 11, 2011.
- Claes Ohlsson, MD, PhD⁎,
- Elizabeth Barrett-Connor, MD‡,
- Shalender Bhasin, MD, PhD§,
- Eric Orwoll, MD, PhD∥,
- Fernand Labrie, MD, PhD¶,
- Magnus K. Karlsson, MD, PhD#,
- Östen Ljunggren, MD, PhD⁎⁎,
- Liesbeth Vandenput, PharmD, PhD⁎,
- Dan Mellström, MD, PhD⁎ and
- Åsa Tivesten, MD, PhD†,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Åsa Tivesten, Wallenberg Laboratory for Cardiovascular Research, Bruna Stråket 16, Sahlgrenska University Hospital, S-413 45 Göteborg, Sweden
Objectives We tested the hypothesis that serum total testosterone and sex hormone–binding globulin (SHBG) levels predict cardiovascular (CV) events in community-dwelling elderly men.
Background Low serum testosterone is associated with increased adiposity, an adverse metabolic risk profile, and atherosclerosis. However, few prospective studies have demonstrated a protective link between endogenous testosterone and CV events. Polymorphisms in the SHBG gene are associated with risk of type 2 diabetes, but few studies have addressed SHBG as a predictor of CV events.
Methods We used gas chromatography/mass spectrometry to analyze baseline levels of testosterone in the prospective population-based MrOS (Osteoporotic Fractures in Men) Sweden study (2,416 men, age 69 to 81 years). SHBG was measured by immunoradiometric assay. CV clinical outcomes were obtained from central Swedish registers.
Results During a median 5-year follow-up, 485 CV events occurred. Both total testosterone and SHBG levels were inversely associated with the risk of CV events (trend over quartiles: p = 0.009 and p = 0.012, respectively). Men in the highest quartile of testosterone (≥550 ng/dl) had a lower risk of CV events compared with men in the 3 lower quartiles (hazard ratio: 0.70, 95% confidence interval: 0.56 to 0.88). This association remained after adjustment for traditional CV risk factors and was not materially changed in analyses excluding men with known CV disease at baseline (hazard ratio: 0.71, 95% confidence interval: 0.53 to 0.95). In models that included both testosterone and SHBG, testosterone but not SHBG predicted CV risk.
Conclusions High serum testosterone predicted a reduced 5-year risk of CV events in elderly men.
This study was supported by the Swedish Research Council, the Swedish Foundation for Strategic Research, the Avtal om Läkarutbildning och Forskning research grant in Gothenburg, the Swedish Heart-Lung Foundation, the Marianne and Marcus Wallenberg Foundation, the Lundberg Foundation, the Torsten and Ragnar Söderberg Foundation, the Åke Wiberg Foundation, and the NovoNordisk Foundation. Dr. Ljunggren has received lecture fees and participated in advisory boards and clinical trials for Eli Lilly, Amgen, MSD, Novartis, and AstraZeneca.
All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. JoAnn E. Manson, MD, DrPH, served as Guest Editor for this paper.
- Received February 26, 2011.
- Accepted July 7, 2011.
- American College of Cardiology Foundation