Transthyretin amyloid cardiomyopathy, an often unrecognized cause of heart failure, is now treatable with a transthyretin stabilizer. It is therefore important to identify at-risk patients who can undergo targeted testing for earlier diagnosis and treatment, prior to the development of irreversible heart failure. Here we show that a random forest machine learning model can identify potential wild-type transthyretin amyloid cardiomyopathy using medical claims data. We derive a machine learning model in 1071 cases and 1071 non-amyloid heart failure controls and validate the model in three nationally representative cohorts (9412 cases, 9412 matched controls), and a large, single-center electronic health record-based cohort (261 cases, 39393 controls). We show that the machine learning model performs well in identifying patients with cardiac amyloidosis in the derivation cohort and all four validation cohorts, thereby providing a systematic framework to increase the suspicion of transthyretin cardiac amyloidosis in patients with heart failure.

SummaryBackgroundSmoking has important health and economic consequences for individuals and society. This study expands the understanding of work‐related burden associated with smoking and benefit of smoking cessation across the US, European Union (EU) and China using large‐scale, representative survey methodology.MethodsData utilised the 2013 National Health and Wellness Survey in United States (US), EU5 (UK, France, Germany, Italy, and Spain) and China. Working‐aged respondents 18‐64 were used in the analyses (US N=58 500; EU5 N=50 417; China N=17 987) and were categorised into: current smokers, trying to quit, former smokers and never smokers. Generalised linear models controlling for demographics and health characteristics examined the relationship of smoking status with work productivity and activity impairment (WPAI‐GH). The WPAI‐GH measures were: absenteeism, presenteeism, overall work impairment, and activity impairment. Separately, current smokers were compared with those who quit 0‐4, 5‐10 and 11 or more years ago on WPAI‐GH end‐points.ResultsCurrent smokers reported greater absenteeism in the US and China and greater presenteeism, overall work impairment, and activity impairment than former and never smokers across the three regions. Those who quit even 0‐4 years ago demonstrated lower absenteeism, presenteeism, and activity impairment in China and lower presenteeism, overall work impairment, and activity impairment in the US and EU5.ConclusionsSmoking was associated with significant work productivity loss in the US, EU5 and China. The results suggest that quitting benefits extend to work productivity rapidly after cessation, serving to further encourage and promote the implementation of workplace cessation programs.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, life-threatening disease characterized by deposition of insoluble amyloid fibrils in the myocardium, resulting in cardiac structural and functional abnormalities and ultimately heart failure. Disease frequency is reportedly lower in women than men, but sex-related differences have not been well established. We conducted a systematic literature review (SLR), based on PRISMA-P guidelines and registered with PROSPERO, to assess whether the epidemiology and clinical presentation of ATTR-CM differ between women and men. MEDLINE, Embase, and Cochrane databases and selected conference proceedings were searched (August 16, 2019) to identify observational and clinical studies reporting sex-specific data for patients with wild-type or hereditary ATTR-CM. Of 193 publications satisfying final eligibility criteria, 69 studies were included in our pooled analysis. Among the 4669 patients with ATTR-CM analyzed, 791 (17%) were women, including 174 (9%), 366 (29%), and 251 (18%) in studies of wild-type, hereditary, and undefined ATTR-CM, respectively. Data available on disease characteristics were limited and very heterogeneous, but trends suggested some cardiac structural/functional differences, i.e., lower interventricular septal and posterior wall thickness and left ventricular (LV) end diastolic diameter, and higher LV ejection fractions, in women versus men across ATTR-CM subtypes. Because LV wall thickness > 12 mm is generally the suggested threshold for ATTR-CM diagnosis in both sexes, smaller cardiac anatomy in women with the disease may lead to underdiagnosis. Additional research and studies are needed to elucidate potential disparities between sexes in ATTR-CM frequency, clinical characteristics, and underlying biological mechanisms. This study was registered within the International Prospective Register of Systematic Reviews (PROSPERO) database of the University of York (CRD42019146995).

Rare diseases are increasingly recognized as a global public health priority. Governments worldwide currently provide important incentives to stimulate the discovery and development of orphan drugs for the treatment of these conditions, but substantial scientific, clinical, and regulatory challenges remain. Tafamidis is a first-in-class, disease-modifying transthyretin (TTR) kinetic stabilizer that represents a major breakthrough in the treatment of transthyretin amyloidosis (ATTR amyloidosis). ATTR amyloidosis is a rare, progressive, and fatal systemic disorder caused by aggregation of misfolded TTR and extracellular deposition of amyloid fibrils in various tissues and organs, including the heart and nervous systems. In this review, we present the successful development of tafamidis spanning 3 decades, marked by meticulous laboratory research into disease mechanisms and natural history, and innovative clinical study design and implementation. These efforts established the safety and efficacy profile of tafamidis, leading to its regulatory approval, and enabled post-approval initiatives that further support patients with ATTR amyloidosis.

This study was sponsored by Pfizer. Gong, Baker, Zou, Bruno, Jumadilova, and Lawrence are employees and stockholders of Pfizer. Wilson and Ewel are employees of United BioSource Corporation, which received funding from Pfizer for conducting this study and for the development of this manuscript. Study concept and design were contributed by Gong, Bruno, and Ewel, with assistance from Jumadilova, Lawrence, and Zou. Gong, Jumadilova, Lawrence, and Ewel collected the data. Data interpretation was performed by Baker, Zou, and Wilson, assisted by Gong, Lawrence, and Ewel. The manuscript was written by Baker, Ewel, and Gong, with assistance from the other authors, and revised by Baker, Wilson, Zou, and Gong, with assistance from Bruno and Jumadilova.