Poster OFICSEL 13 01 2015 - Insuffisance Cardiaque :: ACCUEIL

Impact of low sodium diet on health-related quality of life in
heart failure patients: development and first validation results of
a new burden scale.
Etienne Audureau1, Esther Guéry1, Aline Ferreira Alexandre1, Florence Canouï-Poitrine1, Véronique Benedyga2
Nathalie Goncalves2, Hélène Duchossoir2, Annick Léger2, Charles Taieb3, Thibaud Damy4
1
Public Health Department, CEpiA (EA4393); 2 Dietetic Unit; 4 Heart Failure Unit – Cardiology Department, INSERM U955, Equipe 8, Henri Mondor Hospital, AP-HP, University Paris Est Créteil (UPEC), Créteil, France
3 Laboratoire Pierre Fabre, Paris, France
Introduction
Health-related quality of life (HRQoL) measures and burden
scales have proved to be useful in estimating the impact of diseases and
treatments from the patient’s perspective on its physical, mental and social
health status.
Yet, no data nor scales are currently available with respect to the burden
associated with the low sodium diet usually prescribed in heart failure (HF)
patients, despite the current debate around its efficacy, and whereas
negative effects on HRQoL have been previously reported in other
restricted diets, such as diabetic or gluten-free diets.
Methods
Initial items selection: after extensive literature review, interviews with
patients and multidisciplinary meetings, a set of 14 candidate items were
selected, covering the following domains relating to dietary habits: meals
preparation, pleasure, leisure, social life, vitality and self-rated health.
The validation study was conducted in medically diagnosed HF patients
(NYHA I-IV) prospectively enrolled between 09/2012-09/2013 (Henri
Mondor Hospital, Cardiology Department, Creteil).
Statistical analysis
• Descriptive analyses were performed to study the distribution of individual
items and global score, to inform the acceptability (%missing values) and to
identify potential ceiling and/or floor effects
• Principal component analysis (PCA) was used to examine scale
dimensionality (Horn's Parallel Analysis; Minimum Average Partial Correlation for
Number of Principal Components) and to assess redundancy across items,
omitting items with a factor loading <0.4.
• Internal consistency was assessed with the Cronbach alpha and the
Spearman correlation coefficients between individual items and/or global score.
• Known groups validity was assessed by measuring correlations between the
score and the NYHA class and between the score and the intensity / type of low
sodium diet prescribed.
• Convergent validity was studied by assessing correlations between the global
burden score and the HRQoL Minnesota Living with Heart Failure questionnaire.
Our objective was therefore to develop and validate a low
sodium diet burden scale in heart failure patients.
Results
Of the 152 patients invited, 97 (64%) patients completed and returned the
burden scale (men 72%; mean age 62.5 [±12.3 standard deviation], min 32max 85), of whom 24% with a highly restricted low sodium diet (<3g/d)
Table 1. Labels and response rates of the initial set of 14 candidate items
0:
pas du t ou t
1:
2:
u n pet it peu m oyen n emen t
3:
beau c ou p
4:
én orm ém en t
ne me
concerne pas
Item 1: Je suis obligé de me limiter sur mes plats préférés
18.6%
28.9%
27.8%
18.6%
6.2%
Item 2: Mon appétit est diminué
43.0%
25.8%
20.4%
7.5%
3.2%
Item 3: Chacun de mes repas est un moment difficile
68.8%
15.6%
8.3%
4.2%
3.1%
Item 4: Prendre un repas à l'extérieur est compliqué
42.3%
19.6%
15.5%
13.4%
4.1%
5.2%
Item 5: Faire les courses est compliqué
51.0%
19.4%
7.1%
12.2%
2.0%
8.2%
Item 6: Cela provoque des dépenses supplémentaires
56.0%
23.1%
9.9%
7.7%
3.3%
Item 7: J'ai l'impression d'être une charge pour les personnes qui me préparent mes repas
46.5%
19.2%
11.1%
11.1%
1.0%
Item 8: Cela rend difficile les relations ou les activités avec ma famille ou mes amis
58.2%
20.9%
14.3%
3.3%
3.3%
11.1%
Item 9: Cela rend difficiles mes loisirs
46.2%
15.1%
8.6%
8.6%
12.9%
8.6%
Item 10: Cela m'empêche de partir en voyage/vacances
57.1%
17.6%
7.7%
12.1%
4.4%
1.1%
Item 11: Cela provoque de la fatigue ou de la lassitude
36.5%
29.2%
12.5%
12.5%
8.3%
1.0%
Item 12: Cela est compliqué à gérer dans le cadre de mon activité professionnelle
44.3%
10.2%
8.0%
6.8%
3.4%
27.3%
Item 13: Cela me déprime
64.9%
12.8%
12.8%
3.2%
6.4%
Item 14: Cela aggrave mon état de santé
65.6%
18.3%
7.5%
5.4%
3.2%
Table 1 shows the 14 candidate items and their respective response rates.
Results showed an excellent acceptability of the scale (non response rates per
item from 2.0% to 12.1%)
Unidimensionality was demonstrated in PCA, while items 1 & 2 were finally
left out because of their insufficient loading on the first axis.
A global 12-items burden score was then computed (median global score
6.5/48 [IQR 2-14]; Figure 1)
The scale showed excellent internal consistency (Cronbach alpha=0.908;
Spearman correlation coefficients between items and global score: rhos from
0.59 [burden for holidays] to 0.81 [psychological burden]; p<0.001)
A.
B.
Figure 2. Global burden score according to (a) prescribed low sodium diet and (b) NYHA class
Known groups validity analysis demonstrated the capability of the tool to
discriminate between patients under varying diet restrictions and/or
increasing NYHA class (p=0.05 ; Figure 2).
A good convergent validity was found (significant positive correlations
between the global burden score and dimensions scores from the HRQoL
Minnesota scale: rhos=0.34 [physical dimension], 0.42 [mental], 0.44
[global]; p<0.001)
Conclusions
Figure 1. Distribution of the global 12-items burden score (N=97 HF patients)
These first findings demonstrate the good psychometric
properties of a new specific burden scale that combines high
originality and clinical relevance for the management and
follow-up of heart failure patients.