DIABETIC PERIPHERAL NEUROPATHY- EVALUATION OF THE ASSOCIATION BETWEEN NEUROPATHIC SYMPTOMS (NTSS-6-SA) AND HEALTH-RELATED UTILITY (EQ5D)
Author(s)
Currie CJ1, Covington M2, McEwan P1, Price P1, Morgan CL1, Cawley S3, Peters JR41Cardiff University, Cardiff, Wales, United Kingdom; 2 Eli Lilly and Company, Indianapolis, IN, USA; 3 NHS Wales, Cardiff, Wales, United Kingdom; 4 University Hospital of Wales, Cardiff, Wales, United Kingdom
INTRODUCTION Diabetic peripheral neuropathy (DPN) is a debilitating complication of diabetes and causes sensory symptoms that impact health and functionality. The purpose of this study was to test the hypothesis that there was a direct association between the symptoms associated with DPN (SDPN), as measured by a new instrument the Neuropathy Total Symptom Score (NTSS-6 [self administered]), and health-related utility as measured by the EQ5Dindex. The NTSS-6 provides a score of 0 to 3.66 in each of six domains. The score (range 0 to 21.96) is simply summed with zero meaning no symptoms. METHODS A postal survey using various instruments including the NTSS-6 and the EQ5D was mailed to subjects identified at random as having either type 1 or type 2 diabetes using the same methods as the Health Outcomes Data Repository (HODaR). Univariate and multivariate analysis were applied. This is a preliminary analysis of the first 604 returns. RESULTS The mean age of respondents was 64 years (IQR 55-73); 58% were male and the mean duration of diabetes was 14 years (IQR 5-18). Of the 604 patients, 24% reported having no neuropathic symptoms. The overall mean (SD) EQ5Dindex was 0.65 (0.33), and mean NTSS-6 score 6.2 (median and IQR 4.33, 1.0-10.33). In univariate analysis there was a direct association between the two instruments (correlation coefficient 0.57). Modelling the EQ5Dindex in multiple linear regression analysis to account for confounding, the NTSS-6 score was found to remain directly associated with utility, whereby an increase of one unit on the NTSS-6 resulted in as reduction in the EQ5Dindex of 0.029 units (p<0.001). CONCLUSIONS SDPN, as measured by the NTSS-6, were directly associated with health-related utility. After accounting for confounding factors, a unit change in the NTSS-6 was equivalent to a change in utility that is considered to be clinically meaningful.
Conference/Value in Health Info
2005-11, ISPOR Europe 2005, Florence, Italy
Value in Health, Vol. 8, No.6 (November/December 2005)
Code
PDB58
Topic
Patient-Centered Research
Topic Subcategory
Health State Utilities
Disease
Diabetes/Endocrine/Metabolic Disorders