Freezing of gait (FOG), an episodic gait disturbance characterized by the inability to generate effective stepping, occurs in more than half of Parkinson's disease patients. It is associated with both executive dysfunction and attention and becomes most evident during dual tasking (performing two tasks simultaneously). This study examined the effect of dual motor-cognitive virtual reality training on dual-task performance in FOG. Twenty community dwelling participants with Parkinson's disease (13 with FOG, 7 without FOG) participated in a pre-assessment, eight 20-minute intervention sessions, and a post-assessment. The intervention consisted of a virtual reality maze (DFKI, Germany) through which participants navigated by stepping-in-place on a balance board (Nintendo, Japan) under time pressure. This was combined with a cognitive task (Stroop test), which repeatedly divided participants' attention. The primary outcome measures were pre- and post-intervention differences in motor (stepping time, symmetry, rhythmicity) and cognitive (accuracy, reaction time) performance during single- and dual-tasks. Both assessments consisted of 1) a single cognitive task 2) a single motor task, and 3) a dual motor-cognitive task. Following the intervention, there was significant improvement in dual-task cognitive and motor parameters (stepping time and rhythmicity), dual-task effect for those with FOG and a noteworthy improvement in FOG episodes. These improvements were less significant for those without FOG. This is the first study to show benefit of a dual motor-cognitive approach on dual-task performance in FOG. Advances in such virtual reality interventions for home use could substantially improve the quality of life for patients who experience FOG.

Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use. This paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence. The technology was validated by showing that the doses taken matched the number of audio recordings (r² = 0.94, p<0.01). To demonstrate that audio analysis of inhaler use gives objective information, in vitro studies were performed. These showed that acoustic profiles of inhalations correlated with the peak inspiratory flow rate (r² = 0.97, p20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r² = 0.2) or PEFR (r² = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r² = 0.53, p = 0.01) and PEFR (r² = 0.29, p = 0.01). This study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes. EudraCT 2011-004149-42

Background. For single gait tasks, associations have been reported between gait speed and cognitive domains. However, few studies have evaluated if this association is altered in dual gait tasks given gait speed changes with complexity and nature of task. We evaluated relative contributions of specific elements of cognitive function (including sustained attention and processing speed) to dual task gait speed in a nationally representative population of community-dwelling adults over 50 years.

Rationale: Currently, studies on adherence to inhaled medications report average adherence over time. This measure does not account for variations in the interval between doses, nor for errors in inhaler use. Objectives: To investigate whether adherence calculated as a single area under the (concentration-time) curve (AUC) measure, incorporating the interval between doses and inhaler technique, was more reflective of patient outcomes than were current methods of assessing adherence. Methods: We attached a digital audio device (INhaler Compliance Assessment) to a dry powder inhaler. This recorded when the inhaler was used, and analysis of the audio data indicated if the inhaler had been used correctly. These aspects of inhaler use were combined to calculate adherence over time, as an AUC measure. Over a 3-month period, a cohort of patients with asthma was studied. Adherence to a twice-daily inhaler preventer therapy using this device and clinical measures were assessed. Measurements and Main Results: Recordings from 239 patients with severe asthma were analyzed. Average adherence that was based on the dose counter was 84.4%, whereas the ratio of expected to observed accumulated AUC, actual adherence, was 61.8% (P < 0.01). Of all the adherence measures, only adherence calculated as AUC reflected changes in asthma quality of life, β-agonist reliever use, and peak expiratory flow over the 3 months (P < 0.05 compared with other measures of adherence). Conclusions: Adherence that incorporates the interval between doses and inhaler technique, and calculated as AUC, is more reflective of changes in quality of life and lung function than are the currently used measures of adherence. Clinical trial registered with www.clinicaltrials.gov (NCT 01529697).

Background: Researchers, using checklists, have identified that 30%–90% of patients make errors in inhaler use. It is not certain whether these errors affect the delivery of medication. We have developed an electronic monitor (INCA™) that records audio each time an inhaler is used, providing objective information on inhaler technique. The aim of this study was to assess the effect that correctly identified inhaler errors, with the INCA device, have on drug delivery. Methods: This was a prospective study of healthy volunteers using a salbutamol Diskus™. The inclusion criteria allowed for the recruitment of healthy participants who were nonfrequent users of Salbutamol. Each participant was assigned to one control “phase” first and two/three subsequent error “phases.” Each phase consisted of six doses of the drug taken 6 hours apart, and the participants' blood was drawn before and 25 minutes after doses one and six. This allowed us to sample their trough and peak serum salbutamol levels. Results: Fourteen healthy volunteers were studied. The inhaler technique errors simulated in this study included exhaling into the device after drug priming but before inhalation, low inspiratory flow, multiple inhalations, low breath hold, missed doses, and wrong inhaler position. Only the exhalation error, low inspiratory flow, and missed doses led to a significant reduction in serum salbutamol levels. After six doses of the exhalation error, there was a 62% reduction in peak salbutamol levels. Low inspiratory flow led to a 52% reduction in peak salbutamol levels and a 78% reduction in trough levels. Missed doses led to a 37% reduction in trough salbutamol levels. Conclusions: These findings confirm that technique errors affect drug delivery. Furthermore, we were able to identify that the most critical technique errors with the Diskus inhaler are exhalation into the device before inhalation, poor inspiratory flow, and missing doses.