Implementation of an antimicrobial stewardship program for urinary tract infections in long-term care facilities: a cluster-controlled intervention study.

BACKGROUND: Widespread inappropriate use of antimicrobial substances drives resistance development worldwide. In long-term care facilities (LTCF), antibiotics are among the most frequently prescribed medications. More than one third of antimicrobial agents prescribed in LTCFs are for urinary tract infections (UTI). We aimed to increase the number of appropriate antimicrobial treatments for UTIs in LTCFs using a multi-faceted antimicrobial stewardship intervention. METHODS: We performed a non-randomized cluster-controlled intervention study. Four LTCFs of the Geriatric Health Centers Graz were the intervention group, four LTCFs served as control group. The main components of the intervention were: voluntary continuing medical education for primary care physicians, distribution of a written guideline, implementation of the project homepage to distribute guidelines and videos and onsite training for nursing staff. Local nursing staff recorded data on UTI episodes in an online case report platform. Two blinded reviewers assessed whether treatments were adequate. RESULTS: 326 UTI episodes were recorded, 161 in the intervention group and 165 in the control group. During the intervention period, risk ratio for inadequate indication for treatment was 0.41 (95% CI 0.19-0.90), p = 0.025. In theintervention group, the proportion of adequate antibiotic choices increased from 42.1% in the pre-intervention period, to 45.9% during the intervention and to 51% in the post-intervention period (absolute increase of 8.9%). In the control group, the proportion was 36.4%, 33.3% and 33.3%, respectively. The numerical difference between intervention group and control group in the post-intervention period was 17.7% (difference did not reach statistical significance). There were no significant differences between the control group and intervention group in the safety outcomes (proportion of clinical failure, number of hospital admissions due to UTI and adverse events due to antimicrobial treatment). CONCLUSIONS: An antimicrobial stewardship program consisting of practice guidelines, local and web-based education for nursing staff and general practitioners resulted in a significant increase in adequate treatments (in terms of decision to treat the UTI) during the intervention period. However, this difference was not maintained in the post-intervention phase. Continued efforts to improve the quality of prescriptions further are necessary. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov NCT04798365.

[Prevention of dementia]. / Prävention demenzieller Erkrankungen.

With increasing life expectancy, the prevalence of dementia is increasing worldwide. Dementia is among the greatest challenges for healthcare and social systems of the future. Approximately 40% of newly diagnosed cases of dementia are associated with risk factors that can potentially be influenced by preventive measures. Based on the evidence from longitudinal studies, systematic reviews and meta-analyses, the Lancet commission on dementia prevention, intervention and care has defined 12 risk factors that are associated with an increased risk for dementia: low level of education, hearing impairment, traumatic brain injury, arterial hypertension, diabetes mellitus, smoking, excessive alcohol consumption, depression, obesity, social isolation, and air pollution.

Sustained Increase in Very Low Influenza Vaccination Coverage in Residents and Healthcare Workers of Long-Term Care Facilities in Austria after Educational Interventions.

Residents of long-term care facilities (LTCFs) are particularly at risk for influenza infections. We aimed to improve influenza vaccination coverage among residents and healthcare workers (HCWs) in four LTCFs by implementing educational programs and enhanced vaccination services. We compared vaccination coverage before and after the interventions (2017/18 and 2018/19 seasons). Data on vaccination adherence were recorded during a four-year observational period (2019/20 to 2022/23 seasons). Following the interventions, vaccination coverage increased significantly from 5.8% (22/377) to 19.1% (71/371) in residents and from 1.3% (3/234) to 19.7% (46/233) in HCWs (p < 0.001). During the observational period (2019/20 to 2022/23 seasons), vaccination coverage remained high in residents but decreased in HCWs. Vaccination adherence was significantly higher in residents and HCWs in LTCF 1 compared to the other three LTCFs. Our study suggests that a bundle of educational interventions and enhanced vaccination services can be an effective method for improving influenza vaccination coverage in LTCFs in both residents and HCWs. However, vaccination rates are still well below the recommended targets and further efforts are needed to increase vaccine coverage in our LTCFs.

[Prevention of dementia]. / Prävention demenzieller Erkrankungen.

With increasing life expectancy, the prevalence of dementia is increasing worldwide. Dementia is among the greatest challenges for healthcare and social systems of the future. Approximately 40% of newly diagnosed cases of dementia are associated with risk factors that can potentially be influenced by preventive measures. Based on the evidence from longitudinal studies, systematic reviews and meta-analyses, the Lancet commission on dementia prevention, intervention and care has defined 12 risk factors that are associated with an increased risk for dementia: low level of education, hearing impairment, traumatic brain injury, arterial hypertension, diabetes mellitus, smoking, excessive alcohol consumption, depression, obesity, social isolation, and air pollution.

Comprehensive geriatric assessment.

Geriatric assessment is a multidimensional and interdisciplinarily deployed diagnostic process to evaluate functional capacities and impairments in geriatric patients. The results of geriatric assessment are the basis for planning of therapeutic interventions in the multidisciplinary geriatrics team. Geriatric assessment adds essential information to the state-of-the-art diagnostic tests, such as physical examination, laboratory tests, or imaging techniques, to acquire a holistic picture about health and functional problems and needs of geriatric patients. Studies have demonstrated that geriatric assessment and the following geriatric treatment improves prognosis and increases the chance of older patients remaining in their own home after discharge from hospital after admission for an acute disease.

Analysis of COVID-19 outbreaks in 3 long-term care facilities in Graz, Austria.

BACKGROUND: Nursing homes and long-term care facilities (LTCF) caring for elderly and chronically ill residents are at high risk to experience severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) outbreaks. We report an outbreak of coronavirus disease 2019 (COVID-19) in 3 LTCFs of the Geriatric Health Centres of Graz, Austria lasting from March 22 to April 14, 2020. AIM: The objectives of our study were: (1) to elucidate contributing factors and transmission pathways of SARS-CoV-2, (2) to analyze symptoms of COVID-19 in the residents and health care workers. METHODS: We carried out a retrospective outbreak analysis. FINDINGS: Thirty-six of /277 residents of 3 LTCFs were infected with SARS-CoV-2. Only a quarter of COVID-19 cases among residents had fever ≥38.1°C and 19% suffered from cough. Six of 36 residents remained asymptomatic. Hospitalization rate was 58% in residents. Overall, 33% (12/36) residents infected with SARS-CoV-2 died. Nineteen of 214 health care workers were tested positive for SARS-CoV-2. Universal rt-PCR testing for SARS-CoV-2 of all residents and health care workers as well as infection control measures contributed to ending the outbreaks. CONCLUSIONS: Delayed recognition of possible COVID-19 cases due to either mild symptoms or symptoms that were perceived as atypical early in the pandemic contributed to the transmission of SARS-CoV-2 in LTCFs. This emphasizes the importance of low-threshold testing in LTCF residents.

Prospective Surveillance of Healthcare-Associated Infections in Residents in Four Long-Term Care Facilities in Graz, Austria.

Healthcare-associated infections (HCAI) are a common cause for residents' mortality and morbidity associated with a significant socio-economic burden. Data on HCAIs in Austrian long-term care facilities are scare. Therefore, we evaluated the incidence rate of HCAIs per 1000 resident days in four LTC facilities in Graz, Austria, characterized the spectrum of HCAIs and the use of antimicrobial substances. We conducted a prospective surveillance study from 1 January to 31 December 2018 in four LTCFs of the Geriatric Health Centre of the City of Graz (total of 388 beds). Nursing staff collected data on HCAIs once a week using an electronic reporting system. During the 12-month surveillance period, 252 infections of 165 residents were recorded. The overall incidence rate of HCAIs was 2.1 per 1000 resident days. Urinary tract infections were the most commonly recorded HCAIs (49%, 124/252, 1.03 per 1000 resident days), followed by skin and soft tissue infections and respiratory tract infections. Beta-lactams (ATC class J01C) were prescribed most frequently (63/212), followed by fluoroquinolones (J01M; 54/212). In conclusion, the overall incidence rate for HCAIs was relatively low at 2.1 per 1000 resident days. Our real-life data can serve as a basis for future antimicrobial stewardship and infection prevention interventions.

Diabetes Management According to Health Status in Older Adults with Type 2 Diabetes Staying in Geriatric Care Facilities.

BACKGROUND: About 25% of adults >70 years suffer from type 2 diabetes. Due to the heterogeneity of the geriatric population, guidelines emphasize the need to individualize glycemic goals and simplify treatment strategies with the main focus of avoiding hypoglycemia. The aim of this study was to assess glycemic control in patients with type 2 diabetes in geriatric care facilities based on their individual health status. METHODS: 170 medical records of older adults with type 2 diabetes in geriatric care facilities were retrospectively assessed (64.7% female, age 80 ± 9 years; glycated hemoglobin 6.8% ± 3.6% [51 ± 16 mmol/mol]; body mass index 27.9 ± 5.8 kg/m2). Based on the individual health status, patients were allocated to three groups (healthy n = 27, complex n = 86, and poor n = 57). RESULTS: The overall blood glucose (BG) value was highest in the poor health group with 188 ± 47 mg/dL (poor) vs 167 ± 42 mg/dL (complex) vs 150 ± 34 mg/dL (healthy). BG values of 1.6% (poor) vs 2.8% (complex) vs 1.5% (healthy) of patients were below 90 mg/dL. 36.8% (poor) vs 23.4% (complex) vs 18.5% (healthy) of patients received insulin as the main diabetes therapy, but of these only 14.3% (poor) vs 20% (complex) vs 40% (healthy) were treated with basal insulin. CONCLUSIONS: Overall, BG values were higher in the poor and complex health group. There were a few low BG values in all groups. Although recommended by international guidelines, basal insulin therapy with its low complexity and low hypoglycemic risk is still underused, especially in the poor health group. Therefore, simplification of diabetes therapy should be considered further.

Dysbiosis, gut barrier dysfunction and inflammation in dementia: a pilot study.

BACKGROUND: Dementia is an increasing public health threat worldwide. The pathogenesis of dementia has not been fully elucidated yet. Inflammatory processes are hypothesized to play an important role as a driver for cognitive decline but the origin of inflammation is not clear. We hypothesize that disturbances in gut microbiome composition, gut barrier dysfunction, bacterial translocation and resulting inflammation are associated with cognitive dysfunction in dementia. METHODS: To test this hypothesis, a cohort of 23 patients with dementia and 18 age and sex matched controls without cognitive impairments were studied. Gut microbiome composition, gut barrier dysfunction, bacterial translocation and inflammation were assessed from stool and serum samples. Malnutrition was assessed by Mini Nutritional Assessment Short Form (MNA-SF), detailed information on drug use was collected. Microbiome composition was assessed by 16S rRNA sequencing, QIIME 2 and Calypso 7.14 tools. RESULTS: Dementia was associated with dysbiosis characterized by differences in beta diversity and changes in taxonomic composition. Gut permeability was increased as evidenced by increased serum diamine oxidase (DAO) levels and systemic inflammation was confirmed by increased soluble cluster of differentiation 14 levels (sCD14). BMI and statin use had the strongest impact on microbiome composition. CONCLUSION: Dementia is associated with changes in gut microbiome composition and increased biomarkers of gut permeability and inflammation. Lachnospiraceae NK4A136 group as potential butyrate producer was reduced in dementia. Malnutrition and drug intake were factors, that impact on microbiome composition. Increasing butyrate producing bacteria and targeting malnutrition may be promising therapeutic targets in dementia. TRIAL REGISTRATION: NCT03167983 .

Low prevalence of Clostridium difficile colonization in patients in long-term care facilities in Graz, Austria: A point-prevalence study.

BACKGROUND: We aimed to determine the prevalence of asymptomatic colonization by C. difficile in stool of residents in four long-term care facilities (LTCFs) in Graz, Austria and to identify factors associated with colonization. METHODS: We conducted a point-prevalence study in March 2018. Stool samples were examined by GDH enzyme immunoassay and when positive a toxin A/B-enzyme immunoassay was carried out. Additionally, all samples were tested by toxin A and B PCR and were plated manually as well as in automated fashion onto selective C. difficile agar. RESULTS: In 4/144 (2.8%) residents the GDH assay was positive. Each resident was colonized by a different C. difficile ribotype. C. difficile was not detected in any of the environmental samples. Significantly more colonized residents (60%) had stayed at a hospital in the 3 months previous to the study compared to 10% of non-colonized patients (p=0.01). CONCLUSIONS: The prevalence of colonization by toxigenic C. difficile was 2.8% in patients in LTCFs in Graz, Austria.

["Memory acute"-treatment concept for inpatient remobilization of acutely ill patients with dementia]. / "Memory Akut" ­ Versorgungskonzept zur stationären Remobilisation von akut erkrankten Demenzpatienten.

BACKGROUND: Acute hospitals are generally not designed for people with dementia. Behavioral issues pose the greatest challenge. This article reports on the results of a prospective controlled study designed to assess whether dementia patients benefit from a remobilization strategy in a memory clinic (IG-MA) following hospital discharge. METHODS: Between January and September 2018 patients with moderate to severe dementia discharged from hospital following acute episodes were admitted to an IG-MA for remobilization. The IG-MA unit provides specially qualified personnel and an adapted environment. Control groups were formed from the standard remobilization unit (KG1-AGR) and four care homes (KG2-PWH). RESULTS: Patients in the IG-MA (n = 22) had a worse functional status at admission according to the Barthel index (BI), the timed "up and go" test (TUG) and the Esslinger transfer scale (ETS) than patients in the KG1-AGR (n = 59). Outcomes significantly improved in both groups (IG-MA and KG1-AGR) without a clear difference between groups: IG-MA (BI from 35 to 57.8 points, TUG from 30.8 s to 23 s, ETS from 2.1 to 1.1 points) vs. KG1-AGR (BI from 44.7 to 62.4 points, TUG from 28.6 s to 20.2 s, ETS from 1.7 to 0.9 points). There were differences in cognitive ability at admission (mini mental state examination, MMSE: IG-MA 13.6 points vs. KG1-AGR 20 points). The length of stay in the IG-MA was on average 5 days longer. Early discharge was mostly the result of complications and transfer to acute hospitals in the IG-MA group (22.7%) and in the KG1-AGR group this was mostly due to care issues (27.1%). The KG2-PWH group did not show any significant functional improvements in the first 4 weeks as measured by the BI. CONCLUSION: Moderate to severely affected dementia patients with behavioral problems benefited from treatment in a specially designed remobilization unit following hospital discharge after an acute event.

Optimizing medical care for geriatric patients in Austria: defining a top five list of "Choosing Wisely" recommendations using the Delphi technique.

PURPOSE: Inappropriate use of diagnostic and therapeutic medical procedures is common and potentially harmful for older patients. The Austrian Society of Geriatrics and Gerontology defined a consensus of five recommendations to avoid overuse of medical interventions and to improve care of geriatric patients. METHODS: From an initial pool of 147 reliable recommendations, 20 were chosen by a structured selection process for inclusion in a Delphi process to define a list of five top recommendations for geriatric medicine. 12 experts in the field of geriatric medicine scored the recommendations in two Delphi rounds. RESULTS: The final five recommendations are concerning urinary catheters in elderly patients, percutaneous feeding tubes in patients with advanced dementia, antipsychotics as the first choice to treat behavioral and psychological symptoms of dementia, and screening for breast, colorectal, prostate, or lung cancer, and the use of antimicrobials to treat asymptomatic bacteriuria. CONCLUSIONS: The selected recommendations have the potential to improve medical care for older patients, to reduce side effects caused by unnecessary medical procedures, and to save costs in the health care system.

Towards using fNIRS recordings of mental arithmetic for the detection of residual cognitive activity in patients with disorders of consciousness (DOC).

BACKGROUND: Recently, fNIRS has been proposed as a promising approach for awareness detection, and a possible method to establish basic communication in patients with disorders of consciousness (DOC). AIM: Using fNIRS, the present study evaluated the applicability of auditory presented mental-arithmetic tasks in this respect. METHODS: We investigated the applicability of active attention to serial subtractions for awareness detection in ten healthy controls (HC, 21-32 y/o), by comparing the measured patterns to patterns induced by self-performance of the same task. Furthermore, we examined the suitability of ignoring the given task as additional control signal to implement a two-class brain-computer interface (BCI) paradigm. Finally, we compared our findings in HC with recordings in one DOC patient (78 y/o). RESULTS AND CONCLUSION: Results of the HC revealed no differences between the self-performance and the attention condition, making the attention task suitable for awareness detection. However, there was no general difference between the ignore and attend condition, making the tasks less suitable for BCI control. Despite inconsistent correlations between the patient data and the HC group, single runs of the patient recordings revealed task-synchronous patterns - however, we cannot conclude whether the measured activation derives from instruction based task performance and thus awareness.

Effects of an enhanced iron dense foods offering in the daily meals served in geriatric institutions on measures of iron deficiency anemia.

BACKGROUND: Iron deficiency is one of the most common causes of anemia in geriatric patients. Although the oral iron intake is often inadequate, the potential of iron dense foods in the daily meals of geriatric institutions is rarely considered. To test during a 1- year span whether an improved frequency of iron dense foods in the daily meals has an impact on the oral iron intake, the hemoglobin concentration and anemia prevalence of institutionalized geriatric patients. A parallel, open, pre-and post-oral nutrition intervention study. Two geriatric hospitals participated as intervention centers and one as comparison center. METHODS: In the two intervention centers, a menu plan adapted with iron dense foods was applied. In the comparison center the regular meals provisions was continued. At months 1, 6 and 12 of the intervention time the routine blood-parameter hemoglobin was taken from the geriatric hospital's medical report. Component analysis assessed the nutrient density of the offered meals. 2-day-weighing records realized at month 1 and 6 of intervention-time assessed the iron intake. Ninety-nine geriatric patients in the intervention centers and 37 in the comparison center. All of them had multiple chronic diseases and an average age of 84 years. With the non-parametric Friedmann-Test for repeated measurements, we establish differences within the groups. With the Mann-Whitney-U-Test, we establish differences between the groups. For dichotomous variables, the chi-square-test was used. A p-value of< 0.05 was considered statistically significant for all analyses. RESULTS: In the intervention centers the iron intake (p < 0.001) and the hemoglobin concentration (p = 0.002) improved significantly (p < 0.001). As in the comparison center the frequency of meat and sausage offerings was twice as much as recommended also the hemoglobin concentration improved (p = 0.001). CONCLUSION: Geriatric patients with anemia or low hemoglobin level benefit optimally from a diet rich in iron dense foods. Enhanced access to such can indeed correct iron deficiency anemia. TRIAL REGISTRATION: The ethics committee of the Municipality of Vienna ( EK-13-043-0513 ) approved the study.

Low prevalence of colonization with multidrug-resistant gram-negative bacteria in long-term care facilities in Graz, Austria.

BACKGROUND: Residents in long-term care facilities (LTCFs) are increasingly found to be an important reservoir of multidrug-resistant gram-negative (MRGN) bacteria. AIMS: We aimed to determine colonization by MRGN bacteria over 6 months in LTCFs and geriatric wards in Graz, Austria, and to evaluate risk factors for such colonization. METHODS: During August 2015, we conducted a point-prevalence survey at LTCFs and geriatric wards of the Geriatric Health Centers of the City of Graz. Inguinal and perianal swabs were taken from 137 patients and screened for MRGN using standard procedures. Six months after the initial investigation all colonized patients were sampled again and use of antibiotics, hospital admissions, and mortality was registered. Genetic relatedness of MRGN bacteria was evaluated. RESULTS: We detected 12 patients harboring MRGN isolates (prevalence, 8.7%). Overall inguinal colonization was 5.1%. After 6 months, only 2 out of 12 patients were still colonized. Presence of a urinary catheter was associated with a higher risk of MRGN colonization (odds ratio [OR], 17.5; 95% CI, 1.6-192). Chronic wounds and gastrostomy were also risk factors of MRGN colonization (OR, 10.7; 95% CI, 1.6-69.3 and OR, 18.3; 95% CI, 2.4-139.4, respectively). There was no difference in mortality between colonized and noncolonized patients. CONCLUSIONS: Prevalence of colonization with MRGN bacteria was low in patients in LTCFs and geriatric wards in Graz, Austria.

Colonization of long term care facility patients with MDR-Gram-negatives during an Acinetobacter baumannii outbreak.

BACKGROUND: We aimed to determine the prevalence of colonization by multidrug-resistant Gram-negative bacteria including ESBL-producing enterobacteriaceae, carbapenem-resistant enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii at two wards caring long term for patients with disorder of consciousness at the Geriatric Health Centers Graz, Austria. During our study we detected two A. baumannii outbreaks. METHODS: In August 2015, we conducted a point-prevalence study. Inguinal and perianal swabs were taken from 38 patients and screened for multidrug-resistant Gram-negative rods using standard procedures. Six months after the initial investigation all patients were sampled again and use of antibiotics during the past 6 months and mortality was registered. Genetic relatedness of bacteria was evaluated by DiversiLab system. RESULTS: Fifty percent of patients were colonized by multidrug-resistant Gram-negative isolates. Five patients harboured ESBL-producing enterobacteriaceae. No carbapenem-resistant enterobacteriaceae were detected. 13/38 patients were colonized by A. baumannii isolates (resistant to ciprofloxacin but susceptible to carbapenems). There was a significant difference in the prevalence of colonization by A. baumannii between ward 2 and ward 1 (60% vs. 5.6%, p < 0.001). Two clusters of A. baumannii isolates were identified including one isolate detected on a chair in a patient's room. CONCLUSIONS: We detected a high prevalence of two multidrug-resistant A. baumannii strains in patients with disorder of consciousness at a LTCF in Graz, Austria. Our findings strongly suggest nosocomial cross-transmission between patients. An active surveillance strategy is warranted to avoid missing newly emerging pathogens.

An exploratory intervention study suggests clinical benefits of training in chronic stroke to be paralleled by changes in brain activity using repeated fMRI.

PURPOSE: Previous studies demonstrated changes in sensorimotor network activation over time after stroke that have been interpreted as partly compensatory. Locomotor and balance trainings may improve both mobility and cognition even in chronic stroke and thereby impact on cerebral activation patterns. We here aimed at testing these assumptions in an exploratory study to inform subsequent larger intervention studies. PATIENTS AND METHODS: Eight patients (73.3±4.4 years) with a chronic lacunar stroke (mean interval 3.7 years after the acute event with a range from 2 to 4 years) and residual leg paresis leading to gait disturbance received a guided 5-week training focusing on mobility, endurance, and coordination. Before and afterward, they underwent clinical, neuropsychological, and gait assessments and brain MRI at 3 T including a functional ankle movement paradigm. Sixteen healthy controls (HCs; 68.8±5.4 years) followed the same protocol without intervention. RESULTS: After training, patients had improved in mobility, memory, and delayed recall of memory. While cerebral activations in HC remained completely unaltered, patients showed increased activations in the right precentral gyrus, the right and left superior frontal gyri, and the right frontal lobe, with bipedal ankle movements after training. CONCLUSION: In this exploratory study of chronic stroke, we found not only significant effects of physical training on mobility but also distinct aspects of cognition already with a small number of highly selected patients. These improvements were paralleled by alterations in cerebral activity possibly reflecting neuronal plasticity. Larger studies including randomization are needed.

TP53 Mutational Status and Prediction of Benefit from Adjuvant 5-Fluorouracil in Stage III Colon Cancer Patients.

We investigated the hypothesis that the varying treatment efficacy of adjuvant 5-fluorouracil (5FU) in stage III colon cancer is linked to the TP53 mutational status. ABCSG-90 was a prospective randomized trial in which effect of adjuvant 5FU was studied in stage III colon cancer patients. Tumor material of 70% of these patients (389/572) was available for analysis of the biomarker TP53 using a TP53-gene-specific Sanger sequencing protocol. Median follow-up was 88 months. TP53 mutation frequency was 33%. A significant interaction between TP53 status, outcomes and nodal category was found (P = 0.0095). In the N1 category, TP53 wildtype patients had significantly better overall survival than TP53 mutated (81.0% vs. 62.0% overall survival at 5 years; HR = 2.131; 95% CI: 1.344-3.378; P = 0.0010). In the N2 category, the TP53 status did not affect survival (P = 0.4992). In TP53 wildtype patients, the prognostic significance of N category was significantly enhanced (P = 0.0002). In TP53 mutated patients, survival curves of N1 and N2 patients overlapped and nodal category was no longer prognostic. The biomarker TP53 independently predicted effect of adjuvant 5FU in N1 colon cancer patients. TP53 was not predictive in N2 patients, in whom 5FU is known to have no effect.

Improved concept and first results of an auditory single-switch BCI for the future use in disorders of consciousness patients.

A promising approach to establish basic communication for disorders of consciousness (DOC) patients, is the application of Brain-Computer Interface (BCI) systems, especially the use of single-switch BCIs (ssBCIs). Recently we proposed the concept of a novel auditory ssBCI paradigm and presented first classification results. In this study we report on the evaluation of four different modifications of the original paradigm with the intention to increase the suitability. Therefore we investigated different sound types and the inclusion of additional spatial information. Finally, the classification investigation with the most encouraging modifications shows an enhancement compared to our original paradigm, within healthy subjects, implicating better results for the future use in DOC patients.

Detection of mental imagery and attempted movements in patients with disorders of consciousness using EEG.

Further development of an EEG based communication device for patients with disorders of consciousness (DoC) could benefit from addressing the following gaps in knowledge-first, an evaluation of different types of motor imagery; second, an evaluation of passive feet movement as a mean of an initial classifier setup; and third, rapid delivery of biased feedback. To that end we investigated whether complex and/or familiar mental imagery, passive, and attempted feet movement can be reliably detected in patients with DoC using EEG recordings, aiming to provide them with a means of communication. Six patients in a minimally conscious state (MCS) took part in this study. The patients were verbally instructed to perform different mental imagery tasks (sport, navigation), as well as attempted feet movements, to induce distinctive event-related (de)synchronization (ERD/S) patterns in the EEG. Offline classification accuracies above chance level were reached in all three tasks (i.e., attempted feet, sport, and navigation), with motor tasks yielding significant (p < 0.05) results more often than navigation (sport: 10 out of 18 sessions; attempted feet: 7 out of 14 sessions; navigation: 4 out of 12 sessions). The passive feet movements, evaluated in one patient, yielded mixed results: whereas time-frequency analysis revealed task-related EEG changes over neurophysiological plausible cortical areas, the classification results were not significant enough (p < 0.05) to setup an initial classifier for the detection of attempted movements. Concluding, the results presented in this study are consistent with the current state of the art in similar studies, to which we contributed by comparing different types of mental tasks, notably complex motor imagery and attempted feet movements, within patients. Furthermore, we explored new venues, such as an evaluation of passive feet movement as a mean of an initial classifier setup, and rapid delivery of biased feedback.