Age- and Sex-Related Differences in Patients With Wild-Type Transthyretin Amyloidosis: Insights From THAOS.

Background: Wild-type transthyretin amyloidosis (ATTRwt amyloidosis) is primarily diagnosed in elderly men but diagnoses in younger patients and women have recently increased. Objectives: The purpose of this study was to examine age- and sex-related differences in patients with ATTRwt amyloidosis enrolled in the THAOS (Transthyretin Amyloidosis Outcomes Survey). Methods: THAOS was a global, longitudinal, observational survey of patients with transthyretin amyloidosis, including both hereditary and wild-type disease, and asymptomatic carriers of pathogenic transthyretin gene variants. Patient characteristics at enrollment were analyzed by age at enrollment and sex (data cutoff date: August 1, 2022). Results: Of 1,251 patients with ATTRwt amyloidosis, 13.7%, 49.1%, 34.5%, and 2.8% were aged <70 years, 70 to 79 years, 80 to 89 years, and ≥90 years, respectively. The proportion of women increased with age, from 4.1% in patients aged <70 years to 14.3% in patients aged ≥90 years. In the respective age groups, median time from symptom onset to diagnosis overall (male, female) was 1.7 (1.3, 5.2), 2.0 (2.0, 2.2), 1.8 (1.9, 0.8), and 0.7 (0.6, 2.5) years. A Karnofsky Performance Status score ≤70 was observed in 17.1%, 30.1%, 46.1%, and 44.4% of patients aged <70 years, 70 to 79 years, 80 to 89 years, and ≥90 years, respectively. Conclusions: In this THAOS analysis of patients with ATTRwt amyloidosis, patients were diagnosed an average of 2 years after symptom onset, with the greatest diagnostic delay in women aged <70 years at 5 years. Patients were predominantly men, but the proportion of women increased with age. A substantial proportion of patients had significant functional impairment regardless of age. (Transthyretin Amyloidosis Outcome Survey [THAOS]; NCT00628745).

Response to therapy with tafamidis 61 mg in patients with cardiac transthyretin amyloidosis: real-world experience since approval.

AIMS: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disease that causes heart failure due to amyloid fibril deposition. Tafamidis was approved as the first causal treatment in 2020. We here report on real-world data in patients treated with tafamidis for at least 12 months according to the recently defined European Society for Cardiology (ESC) consensus criteria for disease progression. METHODS AND RESULTS: Three hundred and eight wildtype and 31 hereditary ATTR-CM patients were prospectively enrolled after first diagnosis of ATTR-CM and initiation of tafamidis 61 mg once daily treatment. After 12 months, significant deterioration in Karnofsky Index, estimated glomerular filtration rate (eGFR), N-terminal brain natriuretic peptide (NT-proBNP), septum thickness and left ventricular ejection fraction (LVEF) could be observed, significant disease progression was only detected in 25 patients (9%) using ESC consensus criteria. Mean survival time was 37 months with no differences between responders and non-responders. NT-proBNP was the only independent predictor for poor therapy response (p = .008). CONCLUSIONS: The majority of patients showed no significant disease progression according to the ESC consensus criteria after 12 months of therapy with tafamidis. However, at 12 months, treatment response based on the ESC consensus criteria was not associated with improved survival. Moreover, higher levels of NT-proBNP at diagnosis of ATTR-CM appears to predict poorer treatment response, confirming that timely initiation of therapy is advantageous.

Survival in a Real-World Cohort of Patients With Transthyretin Amyloid Cardiomyopathy Treated With Tafamidis: An Analysis From the Transthyretin Amyloidosis Outcomes Survey (THAOS).

BACKGROUND: In the pivotal Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT), tafamidis significantly reduced mortality rates, leading to its approval in many countries for the treatment of transthyretin amyloid cardiomyopathy (ATTR-CM). Real-world evidence on survival in patients with ATTR-CM following tafamidis treatment has not been extensively reported. METHODS AND RESULTS: The Transthyretin Amyloidosis Outcomes Survey (THAOS) was a longitudinal, observational, phase 4 study of patients with transthyretin amyloidosis and asymptomatic participants carrying pathogenic transthyretin variants. Patients from THAOS with a predominantly cardiac phenotype at enrollment were included, and survival was analyzed according to tafamidis treatment status (treated or untreated). Results are based on the completed THAOS dataset. In tafamidis-treated (n = 587) and tafamidis-untreated (n = 854) patients, respectively, median age at enrollment was 77.7 and 76.4 years, 91.8% and 90.0% were male, and 91.8% and 83.8% had wild-type disease. Survival rates (95% CI) at 30 and 42 months, respectively, were 84.4% (80.5-87.7) and 76.8% (70.9-81.7) in tafamidis-treated patients, and 70.0% (66.4-73.2) and 59.3% (55.2-63.0) in tafamidis-untreated patients. Survival rates in genotype subgroups (wild-type and variant) were similar to those of the overall cohort. Survival rates were better in a contemporary cohort, as reflected by a sensitivity analysis performed in patients enrolled after vs before 2019. No new safety signals were identified. CONCLUSIONS: In this real-world cohort of patients with ATTR-CM, survival rates were higher than in ATTR-ACT and consistent with more recent reports, suggesting early diagnosis and treatment with tafamidis has improved life expectancy in ATTR-CM. These results provide further evidence supporting tafamidis' safety and effectiveness. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00628745.

Prognostic Value of Standard Heart Failure Medication in Patients with Cardiac Transthyretin Amyloidosis.

Introduction: Cardiac transthyretin amyloidosis (ATTR) is a progressive, fatal disease leading to heart failure due to accumulation of amyloid fibrils in the interstitial space and may occur as a hereditary (ATTRv) or wild-type (ATTRwt) form. Guidelines recommend the use of ACE inhibitors (ACEis) and beta-blockers (BBs) as heart failure therapy (HFT) in all patients with symptomatic heart failure and reduced ejection fraction, independent of the underlying etiology. However, the prognostic benefit of ACEis and BBs in ATTR has not been elucidated in detail yet. We thus sought to retrospectively investigate the outcome of patients with ATTRwt or ATTRv under HFT. Methods: Medical records of 403 patients with cardiac ATTR (ATTRwt: n = 268, ATTRv: n = 135) were screened for long-term medication as well as clinical, laboratory, electrocardiographic and echocardiographic data. Patients were assessed between 2005 and 2020 at the University Hospital Heidelberg. Kaplan-Meier analysis was used to analyze potential differences in survival among different subgroups. Results: The mean follow-up was 28 months. In total, 43 patients (32%) with ATTRv and 140 patients (52%) with ATTRwt received HFT. Survival was significantly shorter in patients receiving HFT in ATTRv (46 vs. 83 months, p = 0.0007) vs. non-HFT. A significantly better survival was observed in patients with comorbidities (coronary artery disease, arterial hypertension) and HFT among ATTRwt patients (p = 0.004). No significant differences in survival were observed in the other subgroups. Conclusions: Survival analysis revealed a potential benefit of HFT in patients with ATTRwt and cardiac comorbidities such as coronary artery disease and/or arterial hypertension. In contrast, HFT should be used with caution in patients with ATTRv.

Phenotypic characteristics of F64L, I68L, I107V, and S77Y ATTRv genotypes from the Transthyretin Amyloidosis Outcomes Survey (THAOS).

Transthyretin amyloidosis (ATTR amyloidosis) is a progressive, multi-systemic disease with wild-type (ATTRwt) and hereditary (ATTRv) forms. Over 130 variants associated with ATTRv amyloidosis have been identified, although little is known about the majority of these genotypes. This analysis examined phenotypic characteristics of symptomatic patients with ATTRv amyloidosis enrolled in the Transthyretin Amyloidosis Outcomes Survey (THAOS) with four less frequently reported pathogenic genotypes: F64L (c.250T>C, p.F84L), I68L (c.262A>T, p.I88L), I107V (c.379A>G; p.I127V), and S77Y (c.290C>A; p.S97Y). THAOS is the largest ongoing, global, longitudinal observational study of patients with ATTR amyloidosis, including both ATTRwt and ATTRv amyloidosis. This analysis describes the baseline demographic and clinical characteristics of untreated symptomatic patients with the F64L, I68L, I107V, or S77Y genotypes at enrollment in THAOS (data cutoff date: January 4, 2022). There were 141 symptomatic patients with F64L (n = 46), I68L (n = 45), I107V (n = 21), or S77Y (n = 29) variants at the data cutoff. Most patients were male and median age at enrollment was in the sixth decade for S77Y patients and the seventh decade for the others. A predominantly neurologic phenotype was associated with F64L, I107V, and S77Y genotypes, whereas patients with the I68L genotype presented with more pronounced cardiac involvement. However, a mixed phenotype was also reported in a considerable proportion of patients in each variant subgroup. This analysis from THAOS represents the largest study of ATTRv symptomatic patients with the F64L, I68L, I107V, and S77Y genotypes. These data add to the limited knowledge on the clinical profile of patients with specific ATTRv variants and emphasize the importance of comprehensive assessment of all patients. Trial registration ClinicalTrials.gov: NCT00628745.

Phase 1 Trial of Antibody NI006 for Depletion of Cardiac Transthyretin Amyloid.

BACKGROUND: Transthyretin amyloid (ATTR) cardiomyopathy is a progressive and fatal disease caused by misfolded transthyretin. Despite advances in slowing disease progression, there is no available treatment that depletes ATTR from the heart for the amelioration of cardiac dysfunction. NI006 is a recombinant human anti-ATTR antibody that was developed for the removal of ATTR by phagocytic immune cells. METHODS: In this phase 1, double-blind trial, we randomly assigned (in a 2:1 ratio) 40 patients with wild-type or variant ATTR cardiomyopathy and chronic heart failure to receive intravenous infusions of either NI006 or placebo every 4 weeks for 4 months. Patients were sequentially enrolled in six cohorts that received ascending doses (ranging from 0.3 to 60 mg per kilogram of body weight). After four infusions, patients were enrolled in an open-label extension phase in which they received eight infusions of NI006 with stepwise increases in the dose. The safety and pharmacokinetic profiles of NI006 were assessed, and cardiac imaging studies were performed. RESULTS: The use of NI006 was associated with no apparent drug-related serious adverse events. The pharmacokinetic profile of NI006 was consistent with that of an IgG antibody, and no antidrug antibodies were detected. At doses of at least 10 mg per kilogram, cardiac tracer uptake on scintigraphy and extracellular volume on cardiac magnetic resonance imaging, both of which are imaging-based surrogate markers of cardiac amyloid load, appeared to be reduced over a period of 12 months. The median N-terminal pro-B-type natriuretic peptide and troponin T levels also seemed to be reduced. CONCLUSIONS: In this phase 1 trial of the recombinant human antibody NI006 for the treatment of patients with ATTR cardiomyopathy and heart failure, the use of NI006 was associated with no apparent drug-related serious adverse events. (Funded by Neurimmune; NI006-101 ClinicalTrials.gov number, NCT04360434.).

Long-term efficacy and safety of inotersen for hereditary transthyretin amyloidosis: NEURO-TTR open-label extension 3-year update.

BACKGROUND: Hereditary transthyretin amyloidosis (hATTR/ATTRv) results from the deposition of misfolded transthyretin (TTR) throughout the body, including peripheral nerves. Inotersen, an antisense oligonucleotide inhibitor of hepatic TTR production, demonstrated a favorable efficacy and safety profile in patients with the polyneuropathy associated with hATTR in the NEURO-TTR (NCT01737398) study. We report longer-term efficacy and safety data for inotersen, with a median treatment exposure of 3 years. METHODS: Patients who satisfactorily completed NEURO-TTR were enrolled in its open-label extension (OLE) study. Efficacy assessments included the modified Neuropathy Impairment Score + 7 (mNIS + 7), Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QoL-DN) questionnaire total score, and the Short Form 36 (SF-36v2) Health Survey Physical Component Summary score. Safety and tolerability were also assessed. Efficacy is reported for patients living in Europe and North America (this cohort completed the study approximately 9 months before the remaining group of patients outside these regions); safety is reported for the full safety dataset, comprising patients living in Europe, North America, and Latin America/Australasia. This study is registered with ClinicalTrials.gov, identifier NCT02175004. RESULTS: In the Europe and North America cohort of the NEURO-TTR study, 113/141 patients (80.1%) completed the study, and 109 patients participated in the OLE study. A total of 70 patients continued to receive inotersen (inotersen-inotersen) and 39 switched from placebo to inotersen (placebo-inotersen). The placebo-inotersen group demonstrated sustained improvement in neurological disease progression as measured by mNIS + 7, compared with predicted worsening based on projection of the NEURO-TTR placebo data (estimated natural history). The inotersen-inotersen group demonstrated sustained benefit, as measured by mNIS + 7, Norfolk QoL-DN, and SF-36v2, compared with estimated natural history as well as compared with the placebo-inotersen group. With a maximum exposure of 6.2 years, inotersen was not associated with any additional safety concerns or increased toxicity in the OLE study. Platelet and renal monitoring were effective in reducing the risk of severe adverse events in the OLE study. CONCLUSION: Inotersen treatment for > 3 years slowed progression of the polyneuropathy associated with hATTR, and no new safety signals were observed.

Clinical and genetic profile of patients enrolled in the Transthyretin Amyloidosis Outcomes Survey (THAOS): 14-year update.

BACKGROUND: Transthyretin amyloidosis (ATTR amyloidosis) is a rare, life-threatening disease caused by the accumulation of variant or wild-type (ATTRwt amyloidosis) transthyretin amyloid fibrils in the heart, peripheral nerves, and other tissues and organs. METHODS: Established in 2007, the Transthyretin Amyloidosis Outcomes Survey (THAOS) is the largest ongoing, global, longitudinal observational study of patients with ATTR amyloidosis, including both inherited and wild-type disease, and asymptomatic carriers of pathogenic TTR mutations. This descriptive analysis examines baseline characteristics of symptomatic patients and asymptomatic gene carriers enrolled in THAOS since its inception in 2007 (data cutoff: August 1, 2021). RESULTS: This analysis included 3779 symptomatic patients and 1830 asymptomatic gene carriers. Symptomatic patients were predominantly male (71.4%) and had a mean (standard deviation [SD]) age of symptom onset of 56.3 (17.8) years. Val30Met was the most common genotype in symptomatic patients in South America (80.9%), Europe (55.4%), and Asia (50.5%), and more patients had early- versus late-onset disease in these regions. The majority of symptomatic patients in North America (58.8%) had ATTRwt amyloidosis. The overall distribution of phenotypes in symptomatic patients was predominantly cardiac (40.7%), predominantly neurologic (40.1%), mixed (16.6%), and no phenotype (2.5%). In asymptomatic gene carriers, mean (SD) age at enrollment was 42.4 (15.7) years, 42.4% were male, and 73.2% carried the Val30Met mutation. CONCLUSIONS: This 14-year global overview of THAOS in over 5000 patients represents the largest analysis of ATTR amyloidosis to date and highlights the genotypic and phenotypic heterogeneity of the disease. CLINICALTRIALS: gov Identifier: NCT00628745.

Sex Differences in Wild-Type Transthyretin Amyloidosis: An Analysis from the Transthyretin Amyloidosis Outcomes Survey (THAOS).

INTRODUCTION: Wild-type transthyretin amyloidosis (ATTRwt amyloidosis) is a progressive disease resulting from the accumulation of wild-type transthyretin (TTR) amyloid fibrils, and is diagnosed primarily in males. This analysis examined sex differences in patients with ATTRwt amyloidosis from the Transthyretin Amyloidosis Outcomes Survey (THAOS). METHODS: THAOS is an ongoing, global, longitudinal, observational survey of patients with transthyretin amyloidosis, including both inherited and wild-type disease, and asymptomatic carriers of TTR mutations. THAOS data were analyzed to identify potential differences in demographic and clinical characteristics between males and females with ATTRwt amyloidosis (data cutoff: August 1, 2021). RESULTS: Of 1386 patients with ATTRwt amyloidosis, 84 (6%) were female and 1302 (94%) were male. Females had a higher median age at enrollment (80 vs. 78 years; p = 0.002) and symptom onset (75 vs. 73 years; p = 0.045) than males. Mean left ventricular (LV) ejection fraction was higher (53% vs. 48%; p = 0.001) and mean LV diastolic diameter lower (42 vs. 46 mm; p < 0.001) in females versus males, but sex was not identified as a predictor of LV mean wall thickness adjusted for height (beta coefficient - 0.22; p = 0.460) or a predominantly cardiac phenotype (odds ratio 1.60; p = 0.191). Modified polyneuropathy disability scores differed between groups (p < 0.001), with a larger proportion of scores ≥ IIIa among females (23% vs. 7%). CONCLUSIONS: Females with ATTRwt amyloidosis in THAOS tended to present at a later age and showed signs of less severe cardiac impairment and more severe walking impairment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00628745.

Characteristics of patients with autonomic dysfunction in the Transthyretin Amyloidosis Outcomes Survey (THAOS).

BACKGROUND: Autonomic dysfunction is common in transthyretin amyloidosis (ATTR amyloidosis), but its frequency, characteristics, and quality-of-life (QoL) impact are not well understood. METHODS: The Transthyretin Amyloidosis Outcomes Survey (THAOS) is an ongoing, global, longitudinal survey of patients with ATTR amyloidosis, including patients with inherited (ATTRv) and wild-type (ATTRwt) disease and asymptomatic patients with TTR mutations (ClinicalTrials.gov: NCT00628745). In a descriptive analysis, characteristics and Norfolk QoL-DN total (TQoL) scores at enrolment were compared in patients with vs without autonomic dysfunction (analysis cut-off: 1 August 2020). RESULTS: Autonomic dysfunction occurred in 1181/2922 (40.4%) symptomatic patients, and more commonly in ATTRv (1107/1181 [93.7%]) than ATTRwt (74/1181 [6.3%]) amyloidosis. Time (mean [SD]) from ATTR amyloidosis symptom onset to first autonomic dysfunction symptom was shorter in ATTRv (3.4 [5.7] years) than ATTRwt disease (9.7 [10.4]). In ATTRv disease, patients with vs without autonomic dysfunction had worse QoL (TQoL, 47.3 [33.2] vs 16.1 [18.1]); in ATTRwt disease, those with vs without autonomic dysfunction had similar QoL (23.0 [18.2] vs 19.9 [20.5]). CONCLUSIONS: Autonomic dysfunction was more common and presented earlier in symptomatic ATTRv than ATTRwt amyloidosis and adversely affected QoL in ATTRv disease. These THAOS findings may aid clinicians in diagnosing and treating patients with ATTR amyloidosis. Trial registration: ClinicalTrials.gov: NCT00628745.

Transthyretin cardiac amyloidosis in continental Western Europe: an insight through the Transthyretin Amyloidosis Outcomes Survey (THAOS).

AIMS: Transthyretin amyloidosis (ATTR amyloidosis) is a heterogeneous disorder with cardiac, neurologic, and mixed phenotypes. We describe the phenotypic and genotypic profiles of this disease in continental Western Europe as it appears from the Transthyretin Amyloidosis Survey (THAOS). METHODS AND RESULTS: THAOS is an ongoing, worldwide, longitudinal, observational survey established to study differences in presentation, diagnosis, and natural history in ATTR amyloidosis subjects. At data cut-off, 1411 symptomatic subjects from nine continental Western European countries were enrolled in THAOS [1286 hereditary (ATTRm) amyloidosis; 125 wild-type ATTR (ATTRwt) amyloidosis]. Genotypes and phenotypes varied notably by country. Four mutations (Val122Ile, Leu111Met, Thr60Ala, and Ile68Leu), and ATTRwt, were associated with a mainly cardiac phenotype showing symmetric left ventricular (LV) hypertrophy, normal diastolic LV dimensions and volume, and mildly depressed LV ejection fraction (LVEF). Morphologic and functional abnormalities on echocardiogram were significantly more severe in subjects with cardiac (n'= 210), compared with a mixed (n = 298), phenotype: higher median (Q1-Q3) interventricular septal thickness [18 (16-21) vs. 16 (13-20) mm; P = 0.0006]; and more frequent incidence of LVEF <50% (38.1 vs. 17.5%; P = 0.0008). Subjects with cardiac mutations or ATTRwt (or cardiac or mixed phenotype) had a lower survival rate than subjects in other genotype (or the neurologic phenotype) categories (P < 0.0001, for both). CONCLUSION: ATTR amyloidosis genotypes and phenotypes are highly heterogeneous in continental Western Europe. A geographic map of the different disease profiles and awareness that a subset of subjects have a dominant cardiac phenotype, mimicking hypertrophic cardiomyopathy, at presentation can facilitate the clinical recognition of this underdiagnosed disease. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00628745.

Diagnostic Work-Up of Cardiac Amyloidosis Using Cardiovascular Imaging: Current Standards and Practical Algorithms.

Among non-ischemic cardiomyopathies, cardiac amyloidosis is one of the most common, being caused by extracellular depositions of amyloid fibrils in the myocardium. Two main forms of cardiac amyloidosis are known so far, including 1) light-chain (AL) amyloidosis caused by monoclonal production of light-chains, and 2) transthyretin (ATTR) amyloidosis, caused by dissociation of the transthyretin tetramer into monomers. Both AL and ATTR amyloidosis are progressive diseases with median survival from diagnosis of less than 6 months and 3 to 5 years, respectively, if untreated. In this regard, death occurs in most patients due to cardiac causes, mainly congestive heart failure, which can be prevented due to the presence of effective, life-saving treatment regimens. Therefore, early diagnosis of cardiac amyloidosis is crucial more than ever. However, diagnosis of cardiac amyloidosis may be challenging due to variable clinical manifestations and the perceived rarity of the disease. In this regard, clinical and laboratory reg flags are available, which may help clinicians to raise suspicion of cardiac amyloidosis. In addition, advances in cardiovascular imaging have already revealed a higher prevalence of cardiac amyloidosis in specific populations, so that the diagnosis especially of ATTR amyloidosis has experienced a >30-fold increase during the past ten years. The goal of our review article is to summarize these findings and provide a practical approach for clinicians on how to use cardiovascular imaging techniques, such as echocardiography, cardiac magnetic resonance, bone scintigraphy and, if required, organ biopsy within predefined diagnostic algorithms for the diagnostic work-up of patients with suspected cardiac amyloidosis. In addition, two clinical cases and practical tips are provided in this context.

Temporal Trends of Wild-Type Transthyretin Amyloid Cardiomyopathy in the Transthyretin Amyloidosis Outcomes Survey.

BACKGROUND: Transthyretin amyloid cardiomyopathy results from the accumulation of wild-type (ATTRwt) or variant (ATTRv) transthyretin amyloid fibrils in the myocardium. THAOS (Transthyretin Amyloidosis Outcomes Survey) is a global, longitudinal, observational survey of patients with ATTRv and ATTRwt amyloidosis and asymptomatic patients with transthyretin mutations. OBJECTIVES: This study explored temporal trends in ATTRwt amyloidosis diagnoses using data from THAOS. METHODS: Using THAOS data from December 2007 to January 2020, the following comparisons were made according to year: ATTRwt amyloidosis diagnoses in the United States versus rest of the world, ATTRwt versus ATTRv amyloidosis with cardiac-associated mutations diagnoses, and ATTRwt amyloidosis diagnoses by tissue biopsy versus bone scintigraphy. RESULTS: There were 1,069 patients with ATTRwt amyloidosis and 525 with ATTRv amyloidosis with cardiac mutations enrolled in THAOS. The median time from symptom onset to ATTRwt amyloidosis diagnosis did not change over the past 5 years (>60 months from 2015-2019). ATTRwt amyloidosis diagnoses increased from 2 in 2005 to >100 per year from 2016, with a more pronounced increase in the United States compared with the rest of the world. Diagnoses of ATTRwt amyloidosis by tissue biopsy increased yearly and peaked in 2014 before declining, whereas diagnoses by bone scintigraphy increased markedly since 2011. ATTRv amyloidosis with cardiac mutation diagnoses increased from 3 in 2005 to 37 in 2011, then plateaued. The proportion of patients with ATTRwt amyloidosis diagnosed with New York Heart Association functional class III/IV heart failure decreased from 2012 (46.4%) to 2019 (16.0%). CONCLUSIONS: In the past decade, ATTRwt amyloidosis diagnoses increased worldwide. Despite the growing utilization of bone scintigraphy, patients are diagnosed several years after symptom onset. (Transthyretin Amyloidosis Outcomes Survey [THAOS]; NCT00628745).

Sex-Related Risk of Cardiac Involvement in Hereditary Transthyretin Amyloidosis: Insights From THAOS.

OBJECTIVES: Because patients with ATTRv cardiomyopathy are more likely to be male, this analysis aimed to increase information on associations between sex and genotype, phenotype, and degree of myocardial involvement in ATTRv amyloidosis. BACKGROUND: Transthyretin amyloid cardiomyopathy is a progressive, fatal disease that occurs due to accumulation of wild-type or variant (ATTRv) transthyretin amyloid fibrils in the myocardium. METHODS: The Transthyretin Amyloidosis Outcomes Survey (THAOS) is an ongoing global longitudinal observational survey of patients with ATTR amyloidosis and asymptomatic carriers with TTR mutations. Data from THAOS (data cutoff: January 6, 2020) were analyzed to determine any sex-based differences in genotype, phenotype, and presence of cardiac and neurological symptoms in patients with ATTRv amyloidosis and in patients with ATTRv amyloidosis and cardiomyopathy. RESULTS: There were 2,790 patients with ATTRv amyloidosis enrolled in THAOS, with male patients more likely to have symptoms of cardiac involvement and a cardiac phenotype. Male prevalence was greater in patients with more severe cardiac manifestations of disease, as assessed with N-terminal pro-B-type natriuretic peptide, left-ventricular (LV) ejection fraction, mean LV wall thickness divided by height, and LV mass index divided by height. Sex, age at disease onset, and genotype category were identified by multivariate analyses as risk factors for the development of cardiomyopathy (defined as increased LV septum thickness divided by height). CONCLUSIONS: In this analysis, myocardial involvement was more frequent and pronounced in male patients with ATTRv amyloidosis, suggesting that there may be biological characteristics that inhibit myocardial amyloid infiltration in females or facilitate it in males.