To the Editor In their Teachable Moment in a recent issue of JAMA Internal Medicine,1 Drs Akturk and Nippoldt send the important message that the patient, rather than the testosterone level, should be the indication for exogenous testosterone therapy. That message deserves expansion. Although age-adjusted testosterone levels are not routinely used clinically, it should be acknowledged that total testosterone levels fall at about 1.6% per year and free bioavaliable testosterone levels decease by 2.0% to 3.0% per yer.2 Therefore, a serum testosterone level of 220 ng/dL in a 45-year-old patient may carry different implications than the same level in a 75-year-old patient. The clinical interpretation is made more cumbersome because of the recognized overlap of symptoms between hypogonadism and normal aging. Age-related testosterone levels have the potential to make testosterone prescribing in elderly patients more judicious and to prevent oversubscribing by reacting to the “number” without context.
Loughlin KR. Implications and Interpretations of Differences in Age-Adjusted Testosterone Levels. JAMA Intern Med. 2017;177(5):744. doi:10.1001/jamainternmed.2017.0574