[Show abstract][Hide abstract] ABSTRACT: Background and purpose: Fatigue and pain have been previously shown to be impor-tant determinants for decreasing quality of life (QoL) in one report in patients with non-dystrophic myotonia. The aims of our study were to assess QoL in skeletal muscle channelopathies (SMC) using INQoL (individualized QoL) and SF-36 questionnaires. Methods: We administered INQoL and SF-36 to 66 Italian patients with SMC (26: periodic paralysis, 36: myotonia congenita and 4: Andersen-Tawil) and compared the results in 422 patients with myotonic dystrophies (DM1: 382; and DM2: 40). Results: (i) INQoL index in SMC is similar to that in DMs (P = 0.79). (ii) Patients with myotonia congenita have the worst perception of QoL. (iii) Myotonia has the most detrimental effect on patients with myotonia congenita, followed by patients with DM2 and then by patients with DM1 and hyperkalemic periodic paralysis. (iv) Pain is a significant complaint in patients with myotonia congenita, hypokalemic periodic paralysis and DM2 but not in DM1. (v) Fatigue has a similar detrimental effect on all patient groups except for patients with hyperkalemic periodic paralysis in whom muscle weakness and myotonia more than fatigue affect QoL perception. (vi) Muscle symptoms considered in INQoL correlate with physical symptoms assessed by SF-36 (R from À0.34 to À0.76). Conclusions: QoL perception in patients with SMC is similar to that of patients with DMs, chronic multisystem disabling conditions. Our results provide informa-tion to target treatment and health care of these patients. The sensitivity of INQoL to changes in QoL in the SMC needs to be further explored in longitudinal studies.
European Journal of Neurology 01/2012; 19(11):1470-1476. · 4.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A quality of life (QoL) questionnaire for neuromuscular diseases was recently constructed and validated in the United Kingdom in a sample of adult patients with a variety of muscle disorders. Preliminary results suggested it could be a more relevant and practical measure of QoL in muscle diseases than generic health measures of QoL. The purpose of our work was: (i) To validate INQoL in Italy on a larger sample of adult patients with muscle diseases (ii) to compare INQoL to SF-36.
We have translated into Italian and applied language adaptations to the original UK INQoL version. We studied 1092 patients with different muscle disorders and performed (i) test-retest reliability (n = 80); (ii) psychometric (n = 345), known-group (n = 1092), external criterion (n = 70), and concurrent validity with SF-36 (n = 183).
We have translated and formally validated the Italian version of INQoL confirming and extending results obtained in the United Kingdom. In addition to good results in terms of reliability, known-group and criterion validity, a comparison with the SF-36 scales showed a stronger association between INQoL total index and SF-36 physical (r = -0.72) than mental (r = -0.38) summary health indexes. When considering comparable domains of INQoL and SF-36 with respect to an objective measure of muscle strength assessment (MMRC), regression analysis showed a stronger correlation using INQoL rather than SF-36 scores.
INQoL is recommended to assess QoL in muscle diseases because of its ability to capture physical limitations that are specifically relevant to the muscle condition.
European Journal of Neurology 03/2010; 17(9):1178-87. · 4.16 Impact Factor