Impact of Testosterone Therapy on Hemoglobin Levels in Older Men

Study Overview

In a 2017 study published in JAMA Internal Medicine, researchers investigated the influence of testosterone therapy on hemoglobin levels in older men diagnosed with low testosterone and unexplained anemia. The findings indicated that testosterone therapy can elevate hemoglobin levels not only in men with unexplained anemia but also in those with known causes of anemia and non-anemic individuals. Additionally, the therapy was linked to a decrease in the number of anemic patients.

Anemia in Older Adults

Anemia, characterized by a deficiency of red blood cells or hemoglobin, affects about one-third of older adults without an identifiable cause. This condition is more prevalent in older men compared to women, leading researchers to consider the potential role of declining testosterone levels with age. Prior studies have suggested a correlation between low testosterone levels and unexplained anemia in men, although further investigation is needed to fully understand the impact of testosterone treatment in these cases.

Study Methodology

Participants in the study included men aged 65 and older, all with low blood testosterone levels (below 275 ng/dL) and hemoglobin levels ranging from 10.0 to 12.7 g/dL, who were at low risk for prostate cancer. Based on their medical history and blood tests, they were categorized into three groups: non-anemic, anemic with a known cause, and anemic with an unknown cause.

The participants were assigned to receive either testosterone gel or a placebo for one year, starting at a dosage of 5 g/day and adjusted at various intervals to reflect testosterone levels typical in younger men. Blood samples were collected at the start of the trial and at months 3, 6, 9, and 12. Participants’ walking ability was assessed with a 6-minute walk test, and questionnaires evaluated various health metrics, including sexual desire, energy, fatigue, and memory.

Results and Findings

Out of the 126 anemic participants—64 with known causes of anemia and 62 with unexplained anemia—657 non-anemic men also met the criteria for the study, with a completion rate of 90.5%. The results showed that testosterone therapy led to an increase in hemoglobin levels of at least 1.0 g/dL in significantly more patients across all groups compared to those receiving a placebo. Specifically, after 12 months, 58% of testosterone-treated men with unexplained anemia were no longer anemic, compared to only 22.2% in the placebo group. Similarly, 60% of men with known causes of anemia treated with testosterone were no longer anemic, in contrast to 14.8% of those on placebo.

While the therapy did not significantly alter hemoglobin levels between anemic and non-anemic patients at the study’s outset, it was noted that improvements in walking ability correlated with higher hemoglobin levels and reduced fatigue. Increases of at least 1.0 g/dL in hemoglobin were associated with enhanced general health and energy levels.

Implications of the Study

The study’s findings suggest that testosterone therapy can effectively increase hemoglobin levels in older men suffering from unexplained anemia. Furthermore, the treatment over the course of one year was linked to improved hemoglobin levels across all participants and reductions in both explained and unexplained anemia cases. These results imply that testosterone supplementation may promote red blood cell production in men aged 65 and older with low testosterone levels.

Given the occurrence of elevated hemoglobin and red blood cell counts in some non-anemic participants treated with testosterone, it is advisable to monitor these levels during therapy. The research also highlighted that increased hemoglobin levels contributed to modest improvements in the walking ability and overall vitality of anemic men, as well as enhanced self-reported health and energy across all participants. Future studies utilizing objective measures will be necessary to further validate the health benefits of testosterone therapy in older men with anemia.

Written By: Raishard Haynes, MBS