**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.**
Pedro A. Laires, Alexion–AstraZeneca Rare Disease, Barcelona, Spain

**Main Body of the Abstract**
BACKGROUND:
This study aimed to estimate the prevalence and incidence of transthyretin amyloidosis (ATTR) overall and by phenotype (i.e. cardiomyopathy, ATTR-CM; and polyneuropathy, ATTR-PN) in the US.
METHODS:
A retrospective analysis (Jan2018-Dec2022) was conducted using de-identified patient records sourced from Clarivate’s Claims and EHR databases. Given the lack of well-established coding for ATTR, we developed different algorithms involving ICD-10, SNOMED, and physician notes, thus allowing a range of narrow to broad estimates.
RESULTS:
The overall ATTR cohort consisted of 66.0% males with an average age of 73 (SD: 14) and high multimorbidity as measured by the Charlson Index, 29% having 1 or 2, 18% having 3-4, and 18% having 5 or more conditions.
Using the narrow or broad estimates (table), the 12-month ATTR prevalence of 2020 was found to be between 25.0 (95% CI: 17.1-32.9) per million and 229.4 (95% CI:205.6-253.2) per million; while the 2020 ATTR incidence rates were estimated to be between 8.9 (95% CI:4.9-13.0) and 52.4 (95% CI: 41.0-63.7) per million. The 2020 prevalence ranges (from narrow to broad) per million by ATTR phenotype, were the following: ATTR-CM: 17.4 (95%CI:12.4-22.4) to 173.0 (95%CI:153.3-192.7); ATTR-PN: 7.8 (95%CI:4.2-11.4) to 79.1 (95%CI:65.5-92.8). The 2020 incidence ranges per million were: ATTR-CM: 6.0 (95%CI:3.4-8.6) to 38.2 (95%CI: 29.1-47.4); ATTR-PN: 2.7 (95%CI:0.9-4.4) to 24.2 (95%CI:16.9-31.5).
CONCLUSION:
This study provides updated insights into the epidemiology of ATTR in the US using different data sources, coding systems and case definitions. The broad range reinforces the pressing need for appropriate differential amyloidosis diagnosis and due coding.



**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.**
Pedro A. Laires, _Alexion–AstraZeneca Rare Disease, Barcelona, Spain_

**Main Body of the Abstract**
BACKGROUND:
This study aimed to estimate the prevalence and incidence of transthyretin amyloidosis (ATTR) overall and by phenotype (i.e. cardiomyopathy, ATTR-CM; and polyneuropathy, ATTR-PN) in the US.
METHODS:
A retrospective analysis (Jan2018-Dec2022) was conducted using de-identified patient records sourced from Clarivate’s Claims and EHR databases. Given the lack of well-established coding for ATTR, we developed different algorithms involving ICD-10, SNOMED, and physician notes, thus allowing a range of narrow to broad estimates.
RESULTS:
The overall ATTR cohort consisted of 66.0% males with an average age of 73 (SD: 14) and high multimorbidity as measured by the Charlson Index, 29% having 1 or 2, 18% having 3-4, and 18% having 5 or more conditions.
Using the narrow or broad estimates (table), the 12-month ATTR prevalence of 2020 was found to be between 25.0 (95% CI: 17.1-32.9) per million and 229.4 (95% CI:205.6-253.2) per million; while the 2020 ATTR incidence rates were estimated to be between 8.9 (95% CI:4.9-13.0) and 52.4 (95% CI: 41.0-63.7) per million. The 2020 prevalence ranges (from narrow to broad) per million by ATTR phenotype, were the following: ATTR-CM: 17.4 (95%CI:12.4-22.4) to 173.0 (95%CI:153.3-192.7); ATTR-PN: 7.8 (95%CI:4.2-11.4) to 79.1 (95%CI:65.5-92.8). The 2020 incidence ranges per million were: ATTR-CM: 6.0 (95%CI:3.4-8.6) to 38.2 (95%CI: 29.1-47.4); ATTR-PN: 2.7 (95%CI:0.9-4.4) to 24.2 (95%CI:16.9-31.5).
CONCLUSION:
This study provides updated insights into the epidemiology of ATTR in the US using different data sources, coding systems and case definitions. The broad range reinforces the pressing need for appropriate differential amyloidosis diagnosis and due coding.



Prevalence and incidence of ATTR amyloidosis in the united states: insights from claims database and electronic health records PB54 (#68)

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.