Nutritional status and its impact on transthyretin cardiac amyloidosis: a prospective 1-year study

Introduction

Transthyretin cardiac amyloidosis (ATTR) is an infiltrative disease characterized by the deposit of amyloid fibrils in the myocardium. It leads to progressive heart failure and arrhythmias. Advances in non-invasive diagnostic techniques and therapeutic strategies have increased interest in ATTR, but the impact of nutritional status on disease progression, quality-of-life and clinical outcomes remains unknown.

Purpose

To assess the nutritional status of ATTR patients, to evaluate its association with functional capacity, quality-of-life, and clinical evolution and the impact of nutritional intervention (supplementation or nutritional counselling).

Methods

In this prospective, observational study, 52 patients with ATTR were stratified according to nutritional assessment. Patients were followed for a median of 392 days across three consecutive visits. Malnutrition was defined by GLIM criteria. Clinical characteristics, laboratory biomarkers, nutritional status, quality-of-life and clinically significant decompensation were evaluated.

Results

At baseline, 14 patients (26.9%) met criteria for malnutrition, of whom five received nutritional supplementation. Baseline characteristics are summarized in Table 1.

Malnourished individuals had a higher prevalence of atrial fibrillation (p=0.017), lower KCCQ scores (p=0.006) and reduced functional capacity reflected by shorter 6MWT distance (p=0.011). Malnutrition was also associated with higher SARC-F scores (p=0.020), lower BMI (p=0.011), reduced leg circumference (p<0.001), and a trend toward lower handgrip strength (p=0.057).

During follow-up, well-nourished patients exhibited a progressive decline in quality-of-life scores (KCCQ, EQ-5D), renal function, serum albumin and functional capacity assessed by 6MWT. In this group, 11 hospital admissions (28.9%) were recorded, with no deaths.

In contrast, malnourished patients experienced a significantly higher mortality rate (p=0.003), while the rate of hospital admissions (42.9%) was not significantly different between groups. Among malnourished patients who received nutritional interventions, short-term improvements in 6MWT distance (p=0.020) and handgrip strength (p=0.035) were observed. These benefits were not consistently sustained at the last visit, where a significant decrease in serum albumin was noted (p=0.020).

Conclusion

Malnutrition is a frequent clinically relevant condition in patients with ATTR, associated with poorer functional status, and quality-of-life at baseline, as well as a significantly higher mortality during follow-up. Although short-term improvements in physical performance were observed after nutritional supplementation, no definitive conclusions regarding its impact on clinical outcomes can be drawn. These findings underscore the importance of systematic nutritional assessment in ATTR and the need for larger studies with longer follow-up to clarify the prognostic and therapeutic role of nutritional interventions.Baseline characteristicsFor image description, please refer to the figure legend and surrounding text.