Characterization of peripheral artery disease and associations with traditional risk factors, mobility, and biomarkers in the project baseline health study.

BACKGROUND: There is a dearth of research on immunophenotyping in peripheral artery disease (PAD). This study aimed to describe the baseline characteristics, immunophenotypic profile, and quality of life (QoL) of participants with PAD in the Project Baseline Health Study (PBHS). METHODS: The PBHS study is a prospective, multicenter, longitudinal cohort study that collected clinical, molecular, and biometric data from participants recruited between 2017 and 2018. In this analysis, baseline demographic, clinical, mobility, QoL, and flow cytometry data were stratified by the presence of PAD (ankle brachial index [ABI] ≤0.90). RESULTS: Of 2,209 participants, 58 (2.6%) had lower-extremity PAD, and only 2 (3.4%) had pre-existing PAD diagnosed prior to enrollment. Comorbid smoking (29.3% vs 14%, P < .001), hypertension (54% vs 30%, P < .001), diabetes (25% vs 14%, P = .031), and at least moderate coronary calcifications (Agatston score >100: 32% vs 17%, P = .01) were significantly higher in participants with PAD than in those with normal ABIs, as were high-sensitivity C-reactive protein levels (5.86 vs 2.83, P < .001). After adjusting for demographic and risk factors, participants with PAD had significantly fewer circulating CD56-high natural killer cells, IgM+ memory B cells, and CD10/CD27 double-positive B cells (P < .05 for all). CONCLUSIONS: This study reinforces existing evidence that a large proportion of PAD without claudication may be underdiagnosed, particularly in female and Black or African American participants. We describe a novel immunophenotypic profile of participants with PAD that could represent a potential future screening or diagnostic tool to facilitate earlier diagnosis of PAD. GOV IDENTIFIER: NCT03154346, https://clinicaltrials.gov/ct2/show/NCT03154346.

Cardiovascular Burden of the V142I Transthyretin Variant.

Importance: Individual cohort studies concur that the amyloidogenic V142I variant of the transthyretin (TTR) gene, present in 3% to 4% of US Black individuals, increases heart failure (HF) and mortality risk. Precisely defining carrier risk across relevant clinical outcomes and estimating population burden of disease are important given established and emerging targeted treatments. Objectives: To better define the natural history of disease in carriers across mid to late life, assess variant modifiers, and estimate cardiovascular burden to the US population. Design, Setting, and Participants: A total of 23 338 self-reported Black participants initially free from HF were included in 4 large observational studies across the US (mean [SD], 15.5 [8.2] years of follow-up). Data analysis was performed between May 2023 and February 2024. Exposure: V142I carrier status (n = 754, 3.2%). Main Outcomes and Measures: Hospitalizations for HF (including subtypes of reduced and preserved ejection fraction) and all-cause mortality. Outcomes were analyzed by generating 10-year hazard ratios for each age between 50 and 90 years. Using actuarial methods, mean survival by carrier status was estimated and applied to the 2022 US population using US Census data. Results: Among the 23 338 participants, the mean (SD) age at baseline was 62 (9) years and 76.7% were women. Ten-year carrier risk increased for HF hospitalization by age 63 years, predominantly driven by HF with reduced ejection fraction, and 10-year all-cause mortality risk increased by age 72 years. Only age (but not sex or other select variables) modified risk with the variant, with estimated reductions in longevity ranging from 1.9 years (95% CI, 0.6-3.1) at age 50 to 2.8 years (95% CI, 2.0-3.6) at age 81. Based on these data, 435 851 estimated US Black carriers between ages 50 and 95 years are projected to cumulatively lose 957 505 years of life (95% CI, 534 475-1 380 535) due to the variant. Conclusions and Relevance: Among self-reported Black individuals, male and female V142I carriers faced similar and substantial risk for HF hospitalization, predominantly with reduced ejection fraction, and death, with steep age-dependent penetrance. Delineating the individual contributions of, and complex interplay among, the V142I variant, ancestry, the social construct of race, and biological or social determinants of health to cardiovascular disease merits further investigation.