Table 3. Association between low testosterone and all-cause and cardiovascular mortality.

Study	Study authors’ conclusions
1. Khaw KT, et al. Endogenous testosterone and mortality due to all causes, cardiovascular disease, and cancer in men: European prospective investigation into cancer in Norfolk (EPIC-Norfolk) Prospective Population Study. Circulation 2007;116:2694-701.	“In men, endogenous testosterone concentrations are inversely related to mortality due to cardiovascular disease and all causes. Low testosterone may be a predictive marker for those at high risk of cardiovascular disease.”
2. Laughlin GA, et al. Low serum testosterone and mortality in older men. J Clin Endocrinol Metab 2008;93:68-75.	“Testosterone insufficiency in older men is associated with increased risk of death over the following 20 years, independent of multiple risk factors and several preexisting health conditions.”
3. Menke A, et al. Sex steroid hormone concentrations and risk of death in US men. Am J Epidemiol 2010;171:583-92.	“Men with low free and bioavailable testosterone levels may have a higher risk of mortality within 9 years of hormone measurement.”
4. Tivesten A, et al. Low serum testosterone and estradiol predict mortality in elderly men. J Clin Endocrinol Metab 2009;94:2482-8.	“Elderly men with low serum testosterone and estradiol have increased risk of mortality, and subjects with low values of both testosterone and estradiol have the highest risk of mortality.”
5. Yeap BB, et al. In older men an optimal plasma testosterone is associated with reduced all-cause mortality and higher dihydrotestosterone with reduced ischemic heart disease mortality, while estradiol levels do not predict mortality. J Clin Endocrinol Metab 2014;99:E9-18.	“Optimal androgen levels are a biomarker for survival because older men with midrange levels of T and DHT had the lowest death rates from any cause, whereas those with higher DHT had lower IHD mortality.”
6. Muraleedharan V, et al. Testosterone deficiency is associated with increased risk of mortality and testosterone replacement improves survival in men with type 2 diabetes. Eur J Endocrinol 2013;169:725-33.	“Low testosterone levels predict an increase in all-cause mortality during long-term follow-up. Testosterone replacement may improve survival in hypogonadal men with type 2 diabetes.”
7. Pye SR, et al. Late-onset hypogonadism and mortality in aging men. J Clin Endocrinol Metab 2014;99:1357-66.	“Severe LOH is associated with substantially higher risks of all-cause and cardiovascular mortality, to which both the level of T and the presence of sexual symptoms contribute independently. Detecting low T in men presenting with sexual symptoms offers an opportunity to identify a small subgroup of aging men at particularly high risk of dying.”
8. Hyde Z, et al. Low free testosterone predicts mortality from cardiovascular disease but not other causes: the Health in Men Study. J Clin Endocrinol Metab 2012;97:179-89.	“Low testosterone predicts mortality from CVD but is not associated with death from other causes.”
9. Haring R, et al. Low serum testosterone is associated with increased mortality in men with stage 3 or greater nephropathy. Am J Nephrol 2011;33:209-17.	“In the case of early loss of kidney function, measured TT concentrations might help to detect high-risk individuals for potential therapeutic interventions and to improve mortality risk assessment and outcome.”
10. Kyriazis J, et al. Low serum testosterone, arterial stiffness and mortality in male haemodialysis patients. Nephrol Dial Transplant 2011;26:2971-7.	“We showed that testosterone deficiency in male HD patients is associated with increased CVD and all-cause mortality and that increased arterial stiffness may be a possible mechanism explaining this association.”
11. Carrero JJ, et al. Prevalence and clinical implications of testosterone deficiency in men with end-stage renal disease. Nephrol Dial Transplant 2011;26:184-90.	“Testosterone deficiency is a common finding among male ESRD patients, and it is independently associated with inflammation, cardiovascular co-morbidity and outcome.”
12. Malkin CJ, et al. Low serum testosterone and increased mortality in men with coronary heart disease. Heart 2010;96:1821-5.	“In patients with coronary disease testosterone deficiency is common and impacts significantly negatively on survival.”
13. Corona G, et al. Low testosterone is associated with an increased risk of MACE lethality in subjects with erectile dysfunction. J Sex Med 2010;7(4 Pt 1):1557-64.	“T levels are associated with a higher mortality of MACE. The identification of low T levels should alert the clinician thus identifying subjects with an increased cardiovascular risk.”
14. Ponikowska B, et al. Gonadal and adrenal androgen deficiencies as independent predictors of increased cardiovascular mortality in men with type II diabetes mellitus and stable coronary artery disease. Int J Cardiol 2010;143:343-8.	“In diabetic men with stable CAD, testosterone and DHEAS deficiencies are common and related to high CV mortality. “
15. Militaru C, et al. Serum testosterone and short-term mortality in men with acute myocardial infarction. Cardiol J 2010;17:249-53.	“A low level of T was independently related to total short-term mortality.”
16. Vikan T, et al. Endogenous sex hormones and the prospective association with cardiovascular disease and mortality in men: the Tromsø Study. Eur J Endocrinol 2009;161:435-42.	“Men with free testosterone levels in the lowest quartile had a 24% increased risk of all-cause mortality.”
17. Carrero JJ, et al. Low serum testosterone increases mortality risk among male dialysis patients. J Am Soc Nephrol 2009;20:613-20.	“Among men treated with HD, testosterone concentrations inversely correlate with all-cause and CVD-related mortality, as well as with markers of inflammation. Hypogonadism may be an additional treatable risk factor for patients with chronic kidney disease.”
18. Shores MM, et al. Low serum testosterone and mortality in male veterans. Arch Intern Med 2006;166:1660-5.	“Low testosterone levels were associated with increased mortality in male veterans. Further prospective studies are needed to examine the association between low testosterone levels and mortality.”
19. Shores MM, et al. Testosterone, dihydrotestosterone, and incident cardiovascular disease and mortality in the cardiovascular health study. J Clin Endocrinol Metab 2014;99:2061-8.	“In a cohort of elderly men, DHT and calculated free DHT were associated with incident CVD and all-cause mortality.”
20. Araujo AB, et al. Clinical review: Endogenous testosterone and mortality in men: a systematic review and meta-analysis. J Clin Endocrinol Metab 2011;96:3007-19.	“Low endogenous testosterone levels are associated with increased risk of all-cause and CVD death in community-based studies of men.”
21. Lerchbaum E, et al. Combination of low free testosterone and low vitamin D predicts mortality in older men referred for coronary angiography. Clin Endocrinol (Oxf) 2012;77:475-83.	“A combined deficiency of FT and 25(OH)D is significantly associated with fatal events in a large cohort of men referred for coronary angiography.”

DHT, dihydrotestosterone; IHD, ischemic heart disease; LOH, late onset hypogonadism; CVD, cardiovascular disease; HD, hemodialysis; ESRD, end-stage renal disease; MACE, major adverse cardiovascular events; DHEAS, dehydroepiandrosterone sulphate; FT, free testosterone.