Ieva Laucevičienė

Background and Objectives: The Walking Impairment Questionnaire (WIQ) is a short and simple tool to measure walking impairment for patients with peripheral arterial disease requiring no special equipment or trained staff. The aim of this study was to assess the validity and reliability of the culturally adapted Lithuanian WIQ version in patients with intermittent claudication. Materials and Methods: In total, 40 patients with intermittent claudication and ankle–brachial index < 0.90 participated in this study. Reliability and internal consistency of the questionnaire were assessed by the intra-class correlation coefficient (ICC) and Cronbach’s alpha (α), respectively. Validity was determined by correlations between the WIQ scores and a subjective test (Quality of Life 5 Dimension Questionnaire 3 Level Version (EQ-5D-3L)) and objective tests (6 min walk test (6MWT), treadmill test, and ankle–brachial index). Results: The test–retest reliability was assessed as excellent with an intraclass correlation coefficient of 0.90. The values of Cronbach’s alpha were 0.957 (I time) and 0.948 (II time) and indicated an excellent internal consistency. Statistically significant Spearman correlations were detected between the WIQ and walking distances on the 6MWT (rho 0.514, p < 0.001) and treadmill test (rho 0.515, p < 0.001). Higher WIQ scores were associated with longer walking distances and duration. Moderate negative and low negative correlations were found between the WIQ and EQ-5D-3L scores. Conclusions: The Lithuanian version of culturally adapted WIQ demonstrates reliability and validity for patients with intermittent claudication, supported by two different walking tests showing statistically significant moderate Spearman correlations.

Background and Objectives: The available research shows conflicting data on the heart rate variability (HRV) in metabolic syndrome (MetS) subjects. The discrepancy suggests a methodical shortcoming: due to the influence of physical activity, the standard measuring of HRV at rest is not comparable with HRV assessment based on 24 h Holter monitoring, which is preferred because of its comprehensiveness. To obtain a more reliable measure and to clarify to what extent HRV is altered in MetS, we assessed a 24 h HRV before and after the elimination of the influence of physical activity. Materials and Methods: We investigated 69 metabolic syndrome (MetS) and 37 control subjects, aged 50–55. In all subjects, 24 h monitoring of electrocardiogram, blood pressure, and actigraphy profiles were conducted. To eliminate the influence of day-time physical activity on RR intervals (RRI), a linear polynomial autoregressive model with exogenous terms (ARX) was used. Standard spectral RRI analysis was performed. Results: Subjects with MetS had blunted HRV; the diurnal SDNN index was reliably lower in the MetS group than in control subjects. The elimination of the influence of physical activity did not reveal a significant HRV change in long-term indices (SDNN, SDANN, and SD2), whilst adjacent RRI values (RMSSD, pNN50, and SD1) and SDNN index significantly increased (p < 0.001). An increase in the latter indices highlighted the HRV difference between the MetS and control groups; a significant (p < 0.001) decrease of all short-term HRV variables was found in the MetS group (p < 0.01), and low-frequency spectral components were less pronounced in the MetS group. Conclusion: The application of a polynomial autoregressive model in 24 h HRV assessment allowed for the exclusion of the influence of physical activity and revealed that MetS is associated with blunted HRV, which reflects mitigated parasympathetic tone.