Dr. Ron’s Research Review – January 21, 2015

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This week’s research review focuses on anemia and testosterone, estradiol.

Estradiol in Elderly Men

The MrOS (Osteoporotic Fractures in Men) study included 918 men, median age 75.3 years, range 70-81 years) evaluated total estradiol. Estradiol correlated negatively with age (r=-0.14, p<0.001). Hb correlated (age adjusted) positively with estradiol (r=0.21, p<0.001) and testosterone (r=0.10, p<0.01). After exclusion of subjects with Hb <130g/L and/or testosterone <8 nmol/L (n=99), the correlation between Hb and testosterone was no longer significant, whereas the associations between Hb and estradiol remained. After adjusting for age, BMI and EPO, men with lower estradiol levels were more likely to have Hb in the lowest quartile of values [OR per SD decrease in estradiol = 1.61 (95% CI 1.34-1.93)]. Anemic subjects (Hb <130 g/L) had lower mean estradiol than non-anemic (67.4 vs 79.4 pmol/L, p<0.001). Estradiol correlated, positively and independently, with Hb. Decreased estradiol might partly explain the age-related Hb decline observed in healthy elderly men. (Lewerin et al., 2014)

Testosterone in Older Men and Women

Testosterone and hemoglobin were measured in 905 persons 65 years or older. Total and bioavailable testosterone were associated with hemoglobin levels in women (P = .001 and .02) and in men (P<.001 and .03). Men and women in the lowest quartile of total and bioavailable testosterone were more likely than those in the highest to have anemia (men OR, 5.4; 95% CI, 1.4-21.8 for total and OR, 13.1; 95% CI, 1.5-116.9 for bioavailable testosterone; women OR, 2.1; 95% CI, 0.9-5.0 for total and OR 3.4; 95% CI, 1.2-9.4 for bioavailable testosterone). Among non-anemic participants, men and women with low vs normal total and bioavailable testosterone levels had a significantly higher risk of developing anemia at 3-year follow-up (RR 2.1; 95% CI, 1.1-4.1 for total and RR 3.9; 95% CI, 1.9-7.8 for bioavailable testosterone). Older men and women with low testosterone levels have a higher risk of anemia. (Ferrucci et al., 2006)

Dr. Ron


Articles

 

Low testosterone levels and the risk of anemia in older men and women
            (Ferrucci et al., 2006) Download
BACKGROUND: Anemia is a frequent feature of male hypogonadism and anti-androgenic treatment. We hypothesized that the presence of low testosterone levels in older persons is a risk factor for anemia. METHODS: Testosterone and hemoglobin levels were measured in a representative sample of 905 persons 65 years or older without cancer, renal insufficiency, or anti-androgenic treatments. Hemoglobin levels were reassessed after 3 years. RESULTS: At baseline, 31 men and 57 women had anemia. Adjusting for confounders, we found that total and bioavailable testosterone levels were associated with hemoglobin levels in women (P = .001 and P = .02, respectively) and in men (P<.001 and P = .03, respectively). Men and women in the lowest quartile of total and bioavailable testosterone were more likely than those in the highest to have anemia (men, 14/99 vs 3/100; odds ratio [OR], 5.4; 95% confidence interval [CI], 1.4-21.8 for total and 16/99 vs 1/99; OR, 13.1; 95% CI, 1.5-116.9 for bioavailable testosterone; women, 21/129 vs 12/127; OR, 2.1; 95% CI, 0.9-5.0 for total and 24/127 vs 6/127; OR, 3.4; 95% CI, 1.2-9.4 for bioavailable testosterone). Among nonanemic participants and independent of confounders, men and women with low vs normal total and bioavailable testosterone levels had a significantly higher risk of developing anemia at 3-year follow-up (21/167 vs 28/444; relative risk, 2.1; 95% CI, 1.1-4.1 for total and 26/143 vs 23/468; relative risk, 3.9; 95% CI, 1.9-7.8 for bioavailable testosterone). CONCLUSION: Older men and women with low testosterone levels have a higher risk of anemia.

Serum estradiol associates with blood hemoglobin in elderly men; The MrOS Sweden Study
            (Lewerin et al., 2014) Download
Context: Blood hemoglobin (Hb) declines with age in healthy elderly men, in whom decreasing testosterone has been regarded as part of normal ageing. However, the association between Hb and serum estradiol is incompletely known. Objective: To determine whether estradiol is associated with anemia/Hb and established determinants of Hb in elderly men without prostate cancer. Design, Setting and Participants: The MrOS (Osteoporotic Fractures in Men) is a population-based study (n=918, median age 75.3 years, range 70-81 years). Main Outcome Measures: We evaluated total estradiol in relation to Hb and adjusted for potential confounders (i.e. age, body mass index (BMI), erythropoietin (EPO), total testosterone, cystatin C, iron- and B-vitamin status). Results: Estradiol correlated negatively with age (r=-0.14, p<0.001). Hb correlated (age adjusted) positively with estradiol (r=0.21, p<0.001) and testosterone (r=0.10, p<0.01). Independent predictors for Hb in multivariate analyses were estradiol, EPO, BMI, transferrin saturation, cystatin C and free T4 but not testosterone. After exclusion of subjects with Hb <130g/L and/or testosterone <8 nmol/L (n=99), the correlation between Hb and testosterone was no longer significant, whereas the associations between Hb and estradiol remained. After adjusting for age, BMI and EPO, men with lower estradiol levels were more likely to have Hb in the lowest quartile of values [OR per SD decrease in estradiol = 1.61 (95% CI 1.34-1.93)]. Anemic subjects (Hb <130 g/L) had lower mean estradiol than non-anemic (67.4 vs 79.4 pmol/L, p<0.001). Conclusions: Estradiol correlated, positively and independently, with Hb. Decreased estradiol might partly explain the age-related Hb decline observed in healthy elderly men.

References

Ferrucci, L., et al. (2006), ‘Low testosterone levels and the risk of anemia in older men and women’, Arch Intern Med, 166 (13), 1380-88. PubMedID: 16832003
Lewerin, C., et al. (2014), ‘Serum estradiol associates with blood hemoglobin in elderly men; The MrOS Sweden Study’, J Clin Endocrinol Metab, jc20134111. PubMedID: 24731011