Nationwide prevalence and characteristics of transthyretin amyloid cardiomyopathy in Sweden

Clinical and genetic profiles of patients with hereditary and wild-type transthyretin amyloidosis: the Transthyretin Cardiac Amyloidosis Registry in the state of São Paulo, Brazil (REACT-SP)

BACKGROUND

Transthyretin amyloidosis (ATTR) is a multisystem disease caused by the deposition of fibrillar protein in organs and tissues. ATTR genotypes and phenotypes are highly heterogeneous. We present data on physical signs and symptoms, cardiac and neurological assessments and genetic profile of patients enrolled in the Transthyretin Cardiac Amyloidosis Registry of the State of São Paulo, Brazil.

RESULTS

Six hundred-forty-four patients were enrolled, 505 with the variant form (ATTRv) and 139 with wild-type (ATTRwt). Eleven different mutations were detected, the most common being Val50Met (47.5%) and V142Ile (39.2%). Overall, more than half of the patients presented cardiac involvement, and the difference in this proportion between the ATTRv and ATTRwt groups was significant (43.9 vs. 89.9%; p < 0.001). The prevalence of the neurological phenotype also differed between ATTRv and ATTRwt (56.8 vs. 31.7%; p < 0.001). The mixed phenotype was found in 25.6% of the population, without a significant difference between ATTRv and ATTRwt groups. A group of patients remained asymptomatic (10.4%), with a lower proportion of asymptomatic ATTRwt patients.

CONCLUSIONS

This study details the clinical and genetic spectrum of patients with ATTR in São Paulo, Brazil. This preliminary analysis highlights the considerable phenotypic heterogeneity of neurological and cardiac manifestations in patients with variant and wild-type ATTR.

Carpal Tunnel Syndrome and Transthyretin Amyloidosis in the All of Us Research Program

OBJECTIVE

To evaluate the association of carpal tunnel syndrome (CTS) with incident heart failure and incident amyloidosis and to assess the risk of CTS in pathogenic TTR genetic variant carriers.

METHODS

This prospective cohort study included multiethnic US adults 18 years of age and older without prevalent heart failure and amyloidosis with available genotypic data from the All of Us Research Program. The primary outcomes were incident heart failure and incident amyloidosis. The association of incident heart failure and incident amyloidosis with CTS was assessed using multivariable adjusted Cox models accounting for age, sex, race and ethnicity, obesity, hypertension, diabetes, statin use, and smoking status.

RESULTS

Of the 166,987 individuals included, the median age was 54 (38 to 66) years; 105,279 (63.0%) were female, and 92,780 (55.6%) were non-Hispanic White individuals; CTS was identified in 12,407 (7.4%) individuals. Compared with individuals without CTS, the adjusted hazard ratio for incident heart failure was 1.13 (95% CI, 1.02 to 1.26) in individuals with CTS. The risk of amyloidosis was ∼3-fold higher (adjusted hazard ratio, 2.86; 95% CI, 1.71 to 4.77) in individuals with CTS compared with those without CTS. Individuals carrying a pathogenic TTR variant had an approximately 40% higher risk (adjusted hazard ratio, 1.38; 95% CI, 1.16 to 1.65) for development of CTS compared with noncarriers.

CONCLUSION

Cardiac amyloidosis screening programs may use CTS as a sentinel event and use genetic testing to identify individuals at a higher risk of TTR amyloidosis.

Carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is the most common nerve entrapment disorder worldwide. The epidemiology and risk factors, including family burden, for developing CTS are multi-factorial. Despite much research, its intricate pathophysiological mechanism(s) are not fully understood. An underlying subclinical neuropathy may indicate an increased susceptibility to developing CTS. Although surgery is often performed for CTS, clear international guidelines to indicate when to perform non-surgical or surgical treatment, based on stage and severity of CTS, remain to be elucidated. Neurophysiological examination, using electrophysiology or ultrasonography, performed in certain circumstances, should correlate with the history and findings in clinical examination of the person with CTS. History and clinical examination are particularly relevant globally owing to lack of other equipment. Various instruments are used to assess CTS and treatment outcomes as well as the effect of the disorder on quality of life. The surgical treatment options of CTS - open or endoscopic - offer an effective solution to mitigate functional impairments and pain. However, there are risks of post-operative persistent or recurrent symptoms, requiring meticulous diagnostic re-evaluation before any additional surgery. Health-care professionals should have increased awareness about CTS and all its implications. Future considerations of CTS include use of linked national registries to understand risk factors, explore possible screening methods, and evaluate diagnosis and treatment with a broader perspective beyond surgery, including psychological well-being.

Health care resource use, diagnostic delay and disease burden in transthyretin amyloid cardiomyopathy in Sweden

AIMS

To estimate healthcare resource use and direct healthcare costs of Transthyretin Amyloid Cardiomyopathy (ATTR-CM) in Sweden over 12 months across severity stages as defined by the New York Heart Association (NYHA). Secondary to investigate the current diagnostic trajectory for patients with ATTR-CM in Sweden.

METHODS

A stratified inclusion of patients with a confirmed diagnosis of ATTR-CM in different NYHA classes. Data was extracted from medical records in two cardiology clinics in Sweden. Healthcare resource use data were retrospectively collected for 12 months.

RESULTS

38 patients were included, of whom 7 were in NYHA class II, 20 in class III and 4 in class IV. The total cost of health care per patient increased from SEK 69,000 (€6800) in NYHA stage II, SEK 219,000 (€21,500) in NYHA stage III, to SEK 638,000 (€62,900) in stage IV, mainly due to an increase in inpatient stays. Mean time (standard deviation, SD) from any cardiac related diagnosis prior to ATTR-CM diagnosis was 3.5 (3.1) years.

CONCLUSIONS

Advanced ATTR-CM stages are associated with significant healthcare costs, as patients more often require resource-intensive inpatient care. The current diagnostic trajectory of ATTR-CM in this study was characterized by a diagnostic delay of several years.

ATTR- and AFib amyloid - two different types of amyloid in the annular ligament of trigger finger

INTRODUCTION

Histological examination of tissue specimens obtained during surgical treatment of trigger finger frequently encountered unclassifiable amyloid deposits in the annular ligament. We systematically explored this unknown type by a comprehensive analysis using histology, immunohistochemistry, and quantitative mass spectrometry-based proteomics.

METHODS

205 tissue specimens of annular ligaments were obtained from 172 patients. Each specimen was studied by histology and immunohistochemistry. Tissue specimens obtained from ten patients with histology proven amyloid in annular ligament were analysed by label-free quantitative proteomics. Histological and immunohistochemical findings were correlated with patient demographics.

RESULTS

Amyloid was present as band like deposits along the surface of annular ligament, dot like or patchy deposits within the matrix. Immunohistochemistry identified ATTR amyloid in 92 specimens (mostly patchy in the matrix), while the band like deposits of 100 specimens remained unclassifiable. Proteomic profiles identified the unknown amyloid as most likely of fibrinogen origin. The complete cohort was re-examined by immunohistochemistry using a custom-made antibody and confirmed the presence of fibrinogen alpha-chain (FGA) in a hitherto unclassifiable type of amyloid in annular ligament.

CONCLUSION

Our study shows that two different types of amyloid affect the annular ligament, ATTR amyloid and AFib amyloid, with distinct demographic patient characteristics and histomorphological deposition patterns.

Epidemiology and clinical outcomes of light-chain amyloidosis in Sweden: A nationwide population-based study

OBJECTIVES

This study evaluated data from six Swedish national registries to fill current evidence gaps on the epidemiology, clinical burden, and overall survival (OS) associated with light-chain (AL) amyloidosis.

METHODS

Patients newly diagnosed with AL amyloidosis were identified using six linked Swedish nationwide population-based registers. For each case, individuals from the general population were selected and matched with a maximum ratio of 1:5 based on age, sex, calendar year, and county.

RESULTS

846 patients newly diagnosed with AL amyloidosis and 4227 demographically matched individuals were identified. From 2011 to 2019, annual AL amyloidosis incidence increased from 10.5 to 15.1 cases per million. At baseline, patients with AL amyloidosis had a significantly higher disease burden including higher rates of cardiac and renal failure relative to the comparison group. Among patients with AL amyloidosis, 21.5% had incident heart failure and 17.1% had incident renal failure after initial diagnosis. Median OS for patients with AL amyloidosis was 56 months versus not reached in the matched general population comparison group.

CONCLUSION

The incidence of newly diagnosed AL amyloidosis in Sweden increased over time with AL amyloidosis being associated with a higher risk of cardiac/renal failure and all-cause mortality compared with the general population.

Musculoskeletal manifestations associated with transthyretin-mediated (ATTR) amyloidosis: a systematic review

BACKGROUND

Hereditary and wild-type transthyretin-mediated (ATTRv and ATTRwt) amyloidoses result from the misfolding of transthyretin and aggregation of amyloid plaques in multiple organ systems. Diagnosis of ATTR amyloidosis is often delayed due to its heterogenous and non-specific presentation. This review investigates the association of musculoskeletal (MSK) manifestations with ATTR amyloidosis and the delay from the onset of these manifestations to the diagnosis of ATTR amyloidosis.

METHODS

This systematic review utilized Medline and EMBASE databases. Search criteria were outlined using a pre-specified patient, intervention, comparator, outcome, time, study (PICOTS) criteria and included: amyloidosis, ATTR, and MSK manifestations. Publication quality was assessed utilizing Joanna Briggs Institute (JBI) critical appraisal checklists. The search initially identified 7,139 publications, 164 of which were included. PICOTS criteria led to the inclusion of epidemiology, clinical burden and practice, pathophysiology, and temporality of MSK manifestations associated with ATTR amyloidosis. 163 publications reported on ATTR amyloidosis and MSK manifestations, and 13 publications reported on the delay in ATTR amyloidosis diagnosis following the onset of MSK manifestations.

RESULTS

The MSK manifestation most frequently associated with ATTR amyloidosis was carpal tunnel syndrome (CTS); spinal stenosis (SS) and osteoarthritis (OA), among others, were also identified. The exact prevalence of different MSK manifestations in patients with ATTR amyloidosis remains unclear, as a broad range of prevalence estimates were reported. Moreover, the reported prevalence of MSK manifestations showed no clear trend or distinction in association between ATTRv and ATTRwt amyloidosis. MSK manifestations precede the diagnosis of ATTR amyloidosis by years, and there was substantial variation in the reported delay to ATTR amyloidosis diagnosis. Reports do suggest a longer diagnostic delay in patients with ATTRv amyloidosis, with 2 to 12 years delay in ATTRv versus 1.3 to 1.9 years delay in ATTRwt amyloidosis.

CONCLUSION

These findings suggest that orthopedic surgeons may play a role in the early diagnosis of and treatment referrals for ATTR amyloidosis. Detection of MSK manifestations may enable earlier diagnosis and administration of effective treatments before disease progression occurs.

Amyloid Transthyretin Cardiomyopathy in Elderly Patients With Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

Background The prevalence of calcific aortic stenosis and amyloid transthyretin cardiomyopathy (ATTR-CM) increase with age, and they often coexist. The objective was to determine the prevalence of ATTR-CM in patients with severe aortic stenosis and evaluate differences in presentations and outcomes of patients with concomitant ATTR-CM undergoing transcatheter aortic valve implantation. Methods and Results Prospective screening for ATTR-CM with Technetium99-3,3-diphosphono-1,2-propanodicarboxylic acid bone scintigraphy was performed in 315 patients referred with severe aortic stenosis between August 2019 and August 2021. Myocardial Technetium99-3,3-diphosphono-1,2-propanodicarboxylic acid tracer uptake was detected in 34 patients (10.8%), leading to a diagnosis of ATTR-CM in 30 patients (Perugini ≥2: 9.5%). Age (85.7±4.9 versus 82.8±4.5; P=0.001), male sex (82.4% versus 57.7%; P=0.005), and prior carpal tunnel surgery (17.6% versus 4.3%; P=0.007) were associated with coexisting ATTR-CM, as were ECG (discordant QRS voltage to left ventricular wall thickness [42% versus 12%; P<0.001]), echocardiographic (left ventricular ejection fraction 48.8±12.8 versus 58.4±10.8; P<0.001; left ventricular mass index, 144.4±45.8 versus 117.2±34.4g/m2; P<0.001), and hemodynamic parameters (mean aortic valve gradient, 23.4±12.6 versus 35.5±16.6; P<0.001; mean pulmonary artery pressure, 29.5±9.7 versus 25.8±9.5; P=0.037). Periprocedural (cardiovascular death: hazard ratio [HR], 0.71 [95% CI, 0.04-12.53]; stroke: HR, 0.46 [95% CI, 0.03-7.77]; pacemaker implantation: HR, 1.54 [95% CI, 0.69-3.43]) and 1-year clinical outcomes (cardiovascular death: HR, 1.04 [95% CI, 0.37-2.96]; stroke: HR, 0.34 [95% CI, 0.02-5.63]; pacemaker implantation: HR, 1.50 [95% CI, 0.67-3.34]) were similar between groups. Conclusions Coexisting ATTR-CM was observed in every 10th elderly patient with severe aortic stenosis referred for therapy. While patients with coexisting pathologies differ in clinical presentation and echocardiographic and hemodynamic parameters, peri-interventional risk and early clinical outcomes were comparable up to 1 year after transcatheter aortic valve implantation. REGISTRATION URL: https://www.clinicaltrials.gov. Unique identifier: NCT04061213.

Patisiran for the Treatment of Transthyretin-mediated Amyloidosis with Cardiomyopathy

Transthyretin (TTR) is a tetrameric protein, synthesized primarily by the liver, that acts as a physiological transport protein for retinol and thyroxine. TTR can misfold into pathogenic amyloid fibrils that deposit in the heart and nerves, causing a life-threatening transthyretin amyloidosis cardiomyopathy (ATTR-CM), and a progressive and debilitating polyneuropathy (ATTR-PN). Recent therapeutic advances have resulted in the development of drugs that reduce TTR production. Patisiran is a small interfering RNA that disrupts the complimentary mRNA and inhibits TTR synthesis, and is the first gene-silencing medication licensed for the treatment of ATTR amyloidosis. After encouraging results following the use of patisiran for the treatment of patients with ATTR-PN, there has been increasing interest in the use of patisiran for the treatment of ATTR-CM. Various studies have demonstrated improvements across a wide range of cardiac biomarkers following treatment with patisiran, and have changed the perception of ATTR-CM from being thought of as a terminal disease process, to now being regarded as a treatable disease. These successes represent a huge milestone and have the potential to revolutionize the landscape of treatment for ATTR-CM. However, the long-term safety of patisiran and how best to monitor cardiac response to treatment remain to be determined.

Hemoptysis After Heart Transplantation Caused by Pulmonary Amyloidosis

Pulmonary involvement is a common sequela of systemic amyloidosis, occurring in up to 50% of cases. The patterns of involvement include focal nodular, diffuse interstitial, and tracheobronchial. This can lead to a variety of symptoms, including cough and shortness of breath. Although hemoptysis is not uncommon, massive hemoptysis is rare. (Level of Difficulty: Advanced.).

Health-related quality of life among transthyretin amyloid cardiomyopathy patients

AIMS

Transthyretin amyloid cardiomyopathy (ATTR CM) is a progressive and severe heart disease with physical and psychological implications. The Nordic PROACT study was conducted to investigate the health-related quality of life (HRQoL) in ATTR CM patients.

METHODS AND RESULTS

The Nordic PROACT study was a cross-sectional non-interventional study conducted in 12 cardiology hospital clinics across Norway, Sweden, Finland and Denmark. Men and women aged ≥18 years diagnosed with symptomatic ATTR CM were included. The investigator provided information on medical history, biomarkers, current treatment, co-morbidities and disease severity according to the New York Heart Association (NYHA) class and the National Amyloidosis Centre (NAC) staging. Patients completed the HRQoL questionnaires in the form of the Kansas City Cardiomyopathy Questionnaire (KCCQ), the EQ-5D-5L index with Visual Analog Scale (VAS), and the Major Depression Inventory (MDI). A total of 169 patients (mean ± SD age 77.7 ± 6.2 years) were included. Ninety-two per cent were men. Seventy-six per cent had wildtype ATTR CM (ATTRwt CM) and 15% had a hereditary form of ATTR CM (ATTRv CM) while 9% were genetically unclassified. Most patients were in NYHA class II (54%) and NAC stage 1 (53%). Participation in randomized clinical trials (RCT) was noted in 58% of the patients. The 169 ATTR CM patients had a mean ± SD KCCQ score of 64.3 ± 23.1 for total symptom score, 64.8 ± 20.9 for overall summary score (OSS) and 65.1 ± 21.5 for clinical summary score. The EQ-5D-5L total utility score was 0.8 ± 0.2 and the EQ-5D-5L VAS score was 62.9 ± 20.6. The vast majority (89%) did not report any signs of depression. Patients with ATTRv CM had a higher KCCQ OSS as compared with ATTRwt CM, while EQ-5D-5L utility score, EQ-5D-5L VAS and MDI were similar. Non-RCT participants had a poorer HRQoL as compared with RCT participants as reflected in lower KCCQ OSS and EQ-5D-5L VAS scores and a higher MDI score. Patients with higher NYHA classes and NAC disease stages had a poorer HRQoL as demonstrated by lower KCCQ and EQ-5D-5L scores and higher MDI scores. Correlation between KCCQ, EQ-5D-5L and MDI and the covariate NYHA class remained significant (P < 0.05) after adjusting for multiple testing.

CONCLUSIONS

KCCQ scores were lower than previously reported for patients with other heart diseases of non-ATTR CM origin. The HRQoL measures correlated well to NYHA class and NAC disease stage. The prevalence of depression appeared to be low.

Estimating the Prevalence of Cardiac Amyloidosis in Old Patients with Heart Failure—Barriers and Opportunities for Improvement: The PREVAMIC Study

Background: Cardiac amyloidosis (CA) could be a common cause of heart failure (HF). The objective of the study was to estimate the prevalence of CA in patients with HF. Methods: Observational, prospective, and multicenter study involving 30 Spanish hospitals. A total of 453 patients ≥ 65 years with HF and an interventricular septum or posterior wall thickness > 12 mm were included. All patients underwent a 99mTc-DPD/PYP/HMDP scintigraphy and monoclonal bands were studied, following the current criteria for non-invasive diagnosis. In inconclusive cases, biopsies were performed. Results: The vast majority of CA were diagnosed non-invasively. The prevalence was 20.1%. Most of the CA were transthyretin (ATTR-CM, 84.6%), with a minority of cardiac light-chain amyloidosis (AL-CM, 2.2%). The remaining (13.2%) was untyped. The prevalence was significantly higher in men (60.1% vs 39.9%, p = 0.019). Of the patients with CA, 26.5% had a left ventricular ejection fraction less than 50%. Conclusions: CA was the cause of HF in one out of five patients and should be screened in the elderly with HF and myocardial thickening, regardless of sex and LVEF. Few transthyretin-gene-sequencing studies were performed in older patients. In many patients, it was not possible to determine the amyloid subtype.

RNA Targeting and Gene Editing Strategies for Transthyretin Amyloidosis

Transthyretin (TTR) is a tetrameric protein synthesized primarily by the liver. TTR can misfold into pathogenic ATTR amyloid fibrils that deposit in the nerves and heart, causing a progressive and debilitating polyneuropathy (PN) and life-threatening cardiomyopathy (CM). Therapeutic strategies, which are aimed at reducing ongoing ATTR amyloid fibrillogenesis, include stabilization of the circulating TTR tetramer or reduction of TTR synthesis. Small interfering RNA (siRNA) or antisense oligonucleotide (ASO) drugs are highly effective at disrupting the complementary mRNA and inhibiting TTR synthesis. Since their development, patisiran (siRNA), vutrisiran (siRNA) and inotersen (ASO) have all been licensed for treatment of ATTR-PN, and early data suggest these drugs may have efficacy in treating ATTR-CM. An ongoing phase 3 clinical trial will evaluate the efficacy of eplontersen (ASO) in the treatment of both ATTR-PN and ATTR-CM, and a recent phase 1 trial demonstrated the safety of novel in vivo CRISPR-Cas9 gene-editing therapy in patients with ATTR amyloidosis. Recent results from trials of gene silencer and gene-editing therapies suggest these novel therapeutic agents have the potential to substantially alter the landscape of treatment for ATTR amyloidosis. Their success has already changed the perception of ATTR amyloidosis from a universally progressive and fatal disease to one that is treatable through availability of highly specific and effective disease-modifying therapies. However, important questions remain including long-term safety of these drugs, potential for off-target gene editing, and how best to monitor the cardiac response to treatment.Kindly check and confirm the processed running title.This is correct.

Comparative Structure of Male Mortality From Cardiac Causes in Five-Year Age Groups

Aim      To study the nosological structure of male mortality in 5-year age groups (15-85+) and the contribution of cardiac causes to all-cause mortality in 2020; to discuss the correctness of statistical recording of causes of cardiac death.Material and methods  Data source: Center for Demographic Research of the Russian School of Economy http://demogr.nes.ru / index.php / ru / demogr_indicat / agreement. The selected indexes were all-cause death, causes of the class of circulatory diseases (CD) according to the International Classification of Diseases, Tenth Revision (ICD-10) (class IX, codes I00-I99), and cardiac causes of death (codes I00-I40, I70, I67.4, Q20-28) in 5-year age groups.Results Proportions of CD and cardiac causes in the male all-cause mortality were almost identical in the age groups younger than 30 years. Then the proportion of cardiac deaths remained almost unchanged (30-34 %) in contrast to the rapid growth of the CD proportion (to 51 % with a maximum at 75-79 years). Until the age of 45 years, more than 50% of cardiac deaths were caused by heart defects and cardiomyopathies and more than 25% by acute forms of ischemic heart disease (IHD); in older groups, their proportions decreased but the mortality increased. In the age groups younger than 50 years, the mortality from "Other forms of acute IHD" (ICD codes I20, I24.1-9 counted as one line) was higher than the mortality from myocardial infarction (MI); after 50 years, the MI mortality became higher. The combined proportion of two groups in the mortality from cardiac causes was maximal at the age of 20-24 years (31 %), then it decreased to a minimum of 9 % at the age of 85+. The mortality from and the proportions of chronic forms of IHD (more than 50% of which have no clear criteria for diagnosis and death), arterial hypertension, "Myocardial degeneration" (ICD code I51.5), and "Pulmonary heart and pulmonary circulation disorders" (ICD codes I26-I28) rapidly grow with increasing age. Existing approaches to recording the causes of death do not allow assessment of the contribution and mortality rates from a number of cardiac diseases.Conclusion      Mortality reduction programs should provide more accurate recording of the causes of death and take into account age-related features of the nosological structure of cardiac mortality.

Prevalence estimation of ATTRv in China based on genetic databases

Introduction: Amyloid transthyretin (ATTR) is divided into either hereditary (ATTRv) or sporadic (ATTRwt) and ATTRv is a rare hereditary disease transmitted as an autosomal dominant manner. Its global prevalence is traditionally estimated as 5,000 to 10,000 persons. However, it may be underestimated and the exact prevalence of ATTRv in China mainland remains unknown. Methods: The Genome Aggregation database (gnomAD) database (containing 125,748 exomes) and two genomic sequencing databases--China Metabolic Analytics Project (ChinaMAP) (containing 10588 individuals) and Amcarelab gene database (containing 45392 exomes), were integrated to estimate the prevalence of ATTRv in the world and mainland Chinese populations. Pathogenic variants allele frequency and the prevalence of ATTRv was calculated. Results: Six variants, counting 470 alleles, were defined as pathogenic variants in gnomAD. The prevalence of ATTRv in the world population was 57.4/100,000. Two variants (2 allele counts) and 15 variants (34 individuals) were defined as pathogenic variants in the ChinaMAP database and the Amcarelab exome database, respectively. Thus, the estimated prevalence interval of ATTRv in mainland China was 18.9/100,000-74,9/100,000. Conclusion: The present study demonstrated that the previous prevalence was greatly underestimated using traditional methods. Therefore, raising awareness of the disease is essential for recognizing ATTRv in its early stage.

Prevalence and Clinical Outcomes of Transthyretin Amyloidosis: A Systematic Review and Meta-analysis

BACKGROUND

Systematic evidence on the prevalence and clinical outcome of transthyretin amyloidosis (ATTR) is missing. We explored: a) the prevalence of cardiac amyloidosis in various patient subgroups, b) survival estimates for ATTR subtypes and c) the effects of novel therapeutics on the natural course of disease.

METHODS

A systematic review of literature published in Medline before 31/12/2021 was performed for the prevalence of cardiac amyloidosis & all-cause mortality of ATTR patients. Extracted data included sample size, age, sex, and all-cause mortality at 1, 2 and 5-years. Subgroup analyses were performed for ATTR subtype i.e., wild type ATTR (wtATTR) vs. hereditary ATTR (htATTR), htATTR genotypes and treatment subgroups.

RESULTS

We identified a total of 62 studies (n=277,882 individuals) reporting the prevalence of cardiac amyloidosis, which was high among patients with a hypertrophic cardiomyopathy phenotype, HFpEF, and elderly with aortic stenosis. Data on ATTR mortality were extracted from 95 studies (n=18,238 ATTR patients). Patients with wtATTR were older (p=7x10^-10 ) and more frequently male (p=5x10^-20 ) vs. htATTR. The 2-year survival of ATTR was 73.3% (95%CI 71.6-76.2); for non-subtyped ATTR 70.4% (95%CI 66.9-73.9), for wtATTR (76.0%, 95%CI: 73.0-78.9) and for htATTR (77.2%, 95%CI: 74.0-80.4); in meta-regression analysis wtATTR was associated with higher survival after adjusting for confounders. There was an interaction between survival and htATTR genotypes (p=10^-15 , Val30Met having the lowest and Val122Ile/Thr60Ala the highest mortality). ATTR 2-year survival was higher on tafamidis/patisiran compared to natural disease course (79.9%, 95%CI: 74.4-85.3 vs. 72.4%, 95%CI 69.8-74.9, p<0.05).

CONCLUSIONS

We report the prevalence of ATTR in various population subgroups and provide survival estimates for the natural course of disease and the effects of novel therapeutics. Important gaps in worldwide epidemiology research in ATTR were identified. This article is protected by copyright. All rights reserved.

Prevalence, characteristics, and mortality of patients with transthyretin amyloid cardiomyopathy in the Nordic countries

Aims

Transthyretin amyloid cardiomyopathy (ATTR‐CM) is a progressive condition caused by deposition of transthyretin amyloid fibrils in the heart and is associated with poor quality of life and a shortened lifespan. This study aimed to describe the prevalence, clinical characteristics, and mortality of patients with ATTR‐CM, using multiple national health registers in Denmark, Finland, Norway, and Sweden.

Methods and results

Transthyretin amyloid cardiomyopathy patients were identified during 2008–2018 using a combination of diagnosis codes for amyloidosis and heart disease and were matched to patients with non‐ATTR heart failure (HF). An identical study design was used in each country to facilitate comparison and aggregation of results. A total of 1930 ATTR‐CM patients were identified from national health registers in the four countries. In 2018, prevalence of ATTR‐CM per 100 000 inhabitants ranged from 1.4 in Denmark to 5.0 in Sweden; a steep increase over time was observed in Sweden and Norway. Median survival from diagnosis was 30 months for ATTR‐CM patients and 67 months for matched HF patients. Survival was significantly lower for female than for male ATTR‐CM patients (median survival: 22 and 36 months), while no significant difference was observed in the HF cohort.

Conclusions

This study provides the first nationwide estimates of the prevalence, clinical characteristics, and mortality of patients with ATTR‐CM, using identical study design across several countries. Findings corroborate previous case series showing high mortality in ATTR‐CM, two‐fold higher than for other HF patients and higher in women than men, highlighting the need for more precise and early diagnosis to reduce the disease burden.

Healthcare resource use of patients with transthyretin amyloid cardiomyopathy

Aims

Transthyretin amyloid cardiomyopathy (ATTR‐CM) is the cardiac manifestation of transthyretin amyloidosis (ATTR). The aim of this study was to estimate healthcare resource use for ATTR‐CM patients compared with heart failure (HF) patients, in Denmark, Finland, Norway, and Sweden.

Methods and results

Data from nationwide healthcare registers in the four countries were used. ATTR‐CM patients were defined as individuals diagnosed with amyloidosis and cardiomyopathy or HF between 2008 and 2018. Patients in the ATTR‐CM cohort were matched to patients with HF but without ATTR‐CM diagnosis. Resource use included number of visits to specialty outpatient and inpatient hospital care. A total of 1831 ATTR‐CM and 1831 HF patients were included in the analysis. The mean number of hospital‐based healthcare contacts increased in both the ATTR‐CM and HF cohort during 3 years pre‐diagnosis and was consistently higher for the ATTR‐CM cohort compared with the HF cohort, with 6.1 [CI: 5.9–6.3] vs. 3.2 [CI: 3.1–3.3] outpatient visits and 1.03 [CI: 0.96–1.1] vs. 0.7 [CI: 0.7–0.8] hospitalizations. In the first year following diagnosis, patients with ATTR‐CM continued to visit outpatient care (10.2 [CI: 10.1, 10.4] vs. 5.7 [CI: 5.6, 5.9]) and were admitted to hospital more frequently (3.3 [CI: 3.2, 3.4] vs. 2.5 [CI: 2.5, 2.6]) than HF patients.

Conclusions

Transthyretin amyloid cardiomyopathy imposes a high burden on healthcare systems with twice as many outpatient specialist visits and 50% more hospitalizations in the year after diagnosis compared with HF patients without ATTR‐CM. Studies to investigate if earlier diagnosis and treatment of ATTR‐CM may lower resource use are warranted.