**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Hodrin Kamnang, Brigham and Women's Hospital, Amyloidosis Program, Boston, MA

**Main Body of the Abstract**
BACKGROUND: Male hypogonadism (HG), characterized by low testosterone levels, increases in prevalence with age. The prevalence is high among patients with unspecified heart failure, with an estimate of 20-50%. The prevalence is unknown in ATTR-CM. We therefore sought to determine the prevalence of HG in men with ATTR-CM. METHODS: Serum total testosterone (TT) and free testosterone (FT) were measured in consecutive patients evaluated in a single amyloidosis program. TT was measured by liquid chromatography-tandem mass spectrometry, and FT by equilibrium dialysis. HG was defined as TT <8 nmol/l, or an equivocal TT, 8-12 nmol/L, with FT<220 pmol/l. FT >12 nmol/L was considered normal. Subjects were divided into tertiles by age: <70 (youngest age 56), 70-80 and > 80 years. RESULTS: Among 135 patients, mean age 75+/-7, the prevalence of HG was 51/135 (37%). The majority of those with HG (42/51) had equivocal TT levels with low FT. HG was present in 7/34 (21%) in those age 56-70, 30/77 (39%) age 71-80 and 14/31 (47%) over age 80. CONCLUSIONS: 1. Hypogonadism is common in ATTR-CM patients, increasing with age. 2. Most HG patients have equivocal TT levels in the range often considered “low normal,” but had abnormally low FT. Thus, measurement of FT as well as TT is mandatory. 3. The high prevalence of HG probably represents the known association of HG with heart failure, but other factors cannot be excluded. Further investigation into the clinical correlates and prognostic significance of hypogonadism in ATTR-CM, and the effect of correction, is warranted.



Prevalence of hypogonadism among men with ATTR-cardiomyopathy PB78 (#358)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.