Vocal biomarkers explain quality of life trajectories in patients with heart failure: Findings from the AHF-Voice Study

Introduction: Heart failure (HF) is a common reason for recurrent hospitalization. Daily smartphone-based recording of vocal biomarkers appears promising to remotely monitor patient well-being. The connection of self-reported quality of life and vocal biomarkers in patients with HF is unknown.

 

Methods: AHF-Voice is an ongoing monocentric prospective cohort study, focusing on voice alterations in patients hospitalized with acutely decompensated HF. Exclusion criteria are: listed for heart transplantation, high output HF, history of vocal fold disease/surgery, life-expectancy <6 months. Quality of life is assessed by the 23-item Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OSS). Voice recordings (sustained vowels) are sampled iteratively using a specially developed smartphone app. The current analysis focuses on recordings collected at hospital admission and after 6 weeks of follow-up. Feature extraction of voice recordings were performed using python. Vocal biomarkers associated with changes in quality of life were identified using correlation and regression analysis.

 

Results: In this analysis, 72 patients hospitalized with acute HF were included (n=4 withdrew consent; n=6 excluded due to missing data). Hence, 62 patients were analyzed: mean age 76±10 years, 68% men, 81% in NYHA class III/IV, 47% de novo HF, mean LVEF 48±17%, 44% ischemic cause. Between admission and 6 weeks of follow-up, median KCCQ-OSS improved markedly, i.e. by +25 (4; 41) score points. Selected vocal biomarkers also changed materially (Table) and explained to a large degree the observed change in KCCQ over time: the vocal biomarker panel collected during admission explained 33%, whereas the vocal biomarker panel covering changes over time explained 39%, respectively. Overall, the vocal biomarkers explained 61% of the variance observed for change in KCCQ-OSS (Table).

 

Conclusion: In patients with acute HF, vocal biomarkers substantively explain the variation in quality of life. Tracking vocal biomarkers seems to be a promising low-barrier tool to non-invasively assess patient well-being and holds potential to effectively support heart failure management.


Table: Predictive utility of vocal biomarkers to explain changes in KCCQ-OSS.

 

At hospital
admission

n=62

6-week
follow-up

n=62

Univariable R2 (%)
for changes in KCCQ

Admission

Δ admission
to 6 weeks

F1 mean, × 10²

6.8 (5.9, 7.7)

6.8 (6.0, 7.6)

6.5

12.1

F2 mean, × 10²

12.8 (11.2, 15.5)

12.1 (10.9, 14.1)

2.4

3.4

MFCC 2 median

5 (29)

1 (32)

3.2

3.5

MFCC 13 median

-1 (12)

-2 (14)

1.2

6.4

MFCC 13 mean

-1 (12)

-2 (13)

1.4

7.0

ΔMFCC 11 mean, × 103

-7 (-22, 9)

3 (-14, 20)

4.9

6.0

ΔMFCC 15 mean, × 10²

10 (3)

0 (3)

7.0

9.3

ΔMFCC 22 mean, ×103

5 (-18, 18)

2 (-11, 17)

4.9

6.0

ΔΔ MFCC 3 mean, × 103

-23 (-47, 16)

1 (-29, 46)

8.0

11.3

Zero-crossing median, × 10²

11.8 (8.3, 15.8)

13.6 (10.9, 16.6)

1.2

10.2

Zero-crossing mean, × 10²

11.9 (8.7, 15.9)

13.7 (10.8, 16.9)

0.8

3.3

F2 bandwidth mean, × 10²

10.2 (1.7)

9.8 (1.5)

10.7

14.3

Δ T0 mean, × 107

1 (-4, 8)

1 (-4, 4)

4.4

3.3

 

 

 

33

39

 

 

 

61

 

KCCQ-OSS was measured and vocal biomarkers were extracted both during hospitalization and after 6 weeks of follow-up. Data are mean (SD) or median (quartiles).
R2 = explained variance of vocal biomarker(s) for 6-week change in KCCQ-OSS, using either admission values, or 6-week changes, or the overall information. MFCC = Mel Frequency Cepstral Coefficients; KCCQ-OSS = Kansas City Cardiomyopathy Questionnaire Overall Summary Score.