Is the Concept of Quality of Life Relevant for Multiple Sclerosis Patients with Cognitive Impairment? Preliminary Results of a Cross-Sectional Study

Background: Cognitive impairment occurs in about 50 % of multiple sclerosis (MS) patients, and the use of self-reported outcomes for evaluating treatment and managing care among subjects with cognitive dysfunction has been questioned. The aim of this study was to provide new evidence about the suitability of self-reported outcomes for use in this specific population by exploring the internal structure, reliability and external validity of a specific quality of life (QoL) instrument, the Multiple Sclerosis International Quality of Life questionnaire (MusiQoL). Methods: Design: cross-sectional study. Inclusion criteria: MS patients of any disease subtype. Data collection: sociodemographic (age, gender, marital status, education level, and occupational activity) and clinical data (MS subtype, Expanded Disability Status Scale, disease duration); QoL (MusiQoL and SF36); and neuropsychological performance (Stroop color-word test). Statistical analysis: confirmatory factor analysis, item-dimension correlations, Cronbach’s alpha coefficients, Rasch statistics, relationships between MusiQoL dimensions and other parameters. Principal Findings: One hundred and twenty-four consecutive patients were enrolled. QoL scores did not differ between the 69 cognitively non-impaired patients and the 55 cognitively impaired patients, except for the symptoms dimension. The confirmatory factor analysis performed among the impaired subjects showed that the structure of the questionnaire matched with the initial structure of the MusiQoL. The unidimensionality of the MusiQoL dimensions was preserved, and th

Relevance of Quality of Life Assessment for Multiple Sclerosis Patients with Memory Impairment

<div><h3>Background</h3><p>Memory disturbances, in particular episodic verbal memory dysfunction, are the most frequent cognitive impairment observed in multiple sclerosis (MS) patients. The use of self-reported outcomes for evaluating treatment and managing care of these subjects has been questioned. The aim of this study was to provide new evidence about the suitability of self-reported outcomes for use in this impaired population by exploring the internal structure, reliability and external validity of a specific quality of life (QoL) instrument, the Multiple Sclerosis International Quality of Life questionnaire (MusiQoL).</p> <h3>Methods</h3><p><em>Design</em>: cross-sectional study. <em>Inclusion criteria</em>: MS patients of any disease subtype. <em>Data collection</em>: sociodemographic (age, gender, marital status, education level, and occupational activity) and clinical data (MS subtype, Expanded Disability Status Scale, disease duration); QoL (MusiQoL and SF36); and memory performance (Grober and Buschke test). In accordance with the French norms of the memory test, non-impaired and impaired populations were defined for short- and long-delay free composites and for short- and long-delay total composites. For the 8 populations, psychometric properties were compared to those reported from the reference population assessed in the validation study.</p> <h3>Principal Findings</h3><p>One hundred and twenty-four consecutive patients were enrolled. The analysis performed in the impaired populations showed that the questionnaire structure adequately matched the initial structure of the MusiQoL. The unidimensionality of the dimensions was preserved, and the internal/external validity indices were close to those of the reference population.</p> <h3>Conclusions/Significance</h3><p>Our study suggests that memory dysfunction did not compromise the reliability or validity of the self-reported QoL questionnaires.</p> </div

Internal structural validity/reliability/unidimensionality of the reference population^*.

1<p>Item-Internal Consistency,</p>2<p>Item Discriminant Validity,</p>3<p>Cronbach's alpha,</p>4<p>Rasch statistics.</p>*<p>Simeoni M, Auquier P, Fernandez O, Flachenecker P, Stecchi S, Constantinescu C, Idiman E, Boyko A, Beiske A, Vollmer T, Triantafyllou N, O'Connor P, Barak Y, Biermann L, Cristiano E, Atweh S, Patrick D, Robitail S, Ammoury N, Beresniak A, Pelletier J (2008) Validation of the Multiple Sclerosis International Quality of Life questionnaire. Mult Scler 14:219–230.</p

Associations between MusiQoL dimension scores and sociodemographic characteristics according to the cognitive status.

<p>ADL activity of daily living, PWB psychological well-being, RFr relationships with friends, SPT symptoms, RFa relationships with family, RHCS relationships with health care system, SSL sentimental and sexual life, COP coping, REJ rejection.</p><p>NI non-impaired, I impaired, Ref reference population.</p><p>Bold values: p<0,05.</p><p>Italic characters: reference population values.</p

Correlations between MusiQoL, age and clinical features according to the cognitive status.

<p>ADL activity of daily living, PWB psychological well-being, RFr relationships with friends, SPT symptoms, RFa relationships with family, RHCS relationships with health care system, SSL sentimental and sexual life, COP coping, REJ rejection.</p><p>NI non-impaired, I impaired, Ref reference population.</p><p>Spearman rank correlation coefficients were presented.</p><p>Bold values: p<0,05,</p><p>*p-value<0,05,</p><p>**p-value<0,01.</p><p>Italic characters: reference population values.</p

Suitability indices of construct validity.

<p>Suitability indices of construct validity.</p

Means of dimension/index scores of MusiQoL according to the cognitive status.

<p>Means of dimension/index scores of MusiQoL according to the cognitive status.</p

Psychometric properties of a QoL questionnaire: definitions.

<p>Psychometric properties of a QoL questionnaire: definitions.</p

The suitability indices: decision rules for the construct validity and the external validity.

*<p>100% when the 9 dimensions met the condition, 89% when 8 dimensions met the condition, etc…;</p