Willem J. R. Bossers

Recommended measures for the assessment of cognitive and physical performance in older patients with dementia: a systematic review

Aim/Goal: To recommend a set of neuropsychological and physical exercise tests for researchers to assess cognition and physical fitness in clinical trials with older patients with dementia; to create consensus, decrease heterogeneity, and improve research quality. Methods: A literature search (2005–2011) yielded 89 randomized controlled trials. To provide information on test recommendations the frequency of test use, effect size of the test outcome, study quality, and psychometric properties of tests were analyzed. Results: Fifty-nine neuropsychological tests (cognitive domains: global cognition, executive functioning, memory, and attention) and 10 exercise tests (physical domains: endurance capacity, muscle strength, balance, and mobility) were found. Conclusion: The Severe Impairment Battery, Mini Mental State Examination, and Alzheimer Disease Assessment Scale – cognitive subscale were recommended to measure global cognition. The Verbal Fluency Test Category/Letters, Clock Drawing Test, and Trail Making Test-B were recommended to measure executive functioning. No specific memory test could be recommended. The Digit Span Forward, Digit Span Backward, and Trail Making Test-A were recommended to measure attention. As physical exercise tests, the Timed Up and Go and Six Meter Walk for mobility, the Six Minute Walk Distance for endurance capacity, and the Tinetti Balance Scale were recommended.

Feasibility of a Combined Aerobic and Strength Training Program and Its Effects on Cognitive and Physical Function in Institutionalized Dementia Patients. A Pilot Study

Objectives We examined the feasibility of a combined aerobic and strength training program in institutionalized dementia patients and studied the effects on cognitive and physical function. Methods Thirty-three patients with dementia, recruited from one nursing home, participated in this non-randomized pilot study (25 women; age = 85.2±4.9 years; Mini Mental State Examination = 16.8±4.0). In phase 1 of the study, seventeen patients in the Exercise group (EG) received a combined aerobic and strength training program for six weeks, five times per week, 30 minutes per session, in an individually supervised format and successfully concluded the pre and posttests. In phase 2 of the study, sixteen patients in the Social group (SG) received social visits at the same frequency, duration, and format and successfully concluded the pre and posttests. Results Indices of feasibility showed that the recruitment and adherence rate, respectively were 46.2% and 86.3%. All EG patients completed the exercise program according to protocol without adverse events. After the six-week program, no significant differences on cognitive function tests were found between the EG and SG. There was a moderate effect size in favor for the EG for the Visual Memory Span Forward; a visual attention test. There were significant differences between groups in favor for the EG with moderate to large effects for the physical tests Walking Speed (p = .003), Six-Minute Walk Test (p = .031), and isometric quadriceps strength (p = .012). Conclusions The present pilot study showed that it is feasible to conduct a combined aerobic and strength training program in institutionalized patients with dementia. The selective cognitive visual attention improvements and more robust changes in motor function in favor of EG vs. SG could serve as a basis for large randomized clinical trials. Trial Registration trialregister.nl 1230

The Groningen Meander Walking Test: A Dynamic Walking Test for Older Adults With Dementia

Background Current dynamic walking tests, used in studies with older adults with dementia, rely strongly on healthy cognitive and physical function. Therefore, the Groningen Meander Walking Test (GMWT) was developed specifically for people with dementia. The aim of the GMWT is to measure dynamic walking ability by walking over a meandering curved line, with an emphasis on walking speed and stepping accuracy, while changing direction. Objective The purpose of this study was to investigate the feasibility, test-retest reliability, and minimal detectable change (MDC) of the GMWT. Design A repeated-measures design was used. Methods Forty-two people with dementia participated in the study. Adherence rate, adverse events, repetition of instructions during test performance, test duration, and number of oversteps were assessed. Results The adherence rate was excellent, with no adverse events. No repetitive instructions were given during test performance, and test duration was short (mean=17.16 seconds) with few oversteps (mean=1.94 oversteps). Test-retest reliability for participants without a walking device was excellent for the GMWT time score (intraclass correlation coefficient [ICC]=.942), with an MDC of 2.96 seconds. Test-retest reliability for participants with a 4-wheeled walker (4WW) was moderate (ICC=.837), with an MDC of 10.35 seconds. For the overstep score, a marginal ICC of .630 was found, with an MDC of 4.38 oversteps. Limitations No fall data were available, and there was a volunteer bias. Conclusions The GMWT is a feasible test for people with dementia. With the GMWT time score, a reliable and sensitive field test to measure walking abilities in older adults with dementia is available. The GMWT overstep score can be used to give information about the execution according to protocol and should be emphasized during the instructions. Future studies need to investigate the validity of the GMWT.

Positive effects of combined cognitive and physical exercise training on cognitive function in older adults with mild cognitive impairment or dementia: A meta-analysis

Combined cognitive and physical exercise interventions have potential to elicit cognitive benefits in older adults with mild cognitive impairment (MCI) or dementia. This meta-analysis aims to quantify the overall effect of these interventions on global cognitive functioning in older adults with MCI or dementia. Ten randomized controlled trials that applied a combined cognitive-physical intervention with cognitive function as an outcome measure were included. For each study effect sizes were computed (i.e., post-intervention standardized mean difference (SMD) scores) and pooled, using a random-effects meta-analysis. The primary analysis showed a small-to-medium positive effect of combined cognitive-physical interventions on global cognitive function in older adults with MCI or dementia (SMD[95% confidence interval]=0.32[0.17;0.47], p<0.00). A combined intervention was equally beneficial in patients with dementia (SMD=0.36[0.12;0.60], p<0.00) and MCI (SMD=0.39[0.15;0.63], p<0.05). In addition, the analysis showed a moderate-to-large positive effect after combined cognitive-physical interventions for activities of daily living (ADL) (SMD=0.65[0.09;1.21], p<0.01)and a small-to-medium positive effect for mood (SMD=0.27[0.04;0.50], p<0.01). These functional benefits emphasize the clinical relevance of combined cognitive and physical training strategies.

Comparison of Effect of Two Exercise Programs on Activities of Daily Living in Individuals with Dementia: A 9-Week Randomized, Controlled Trial

To compare the effects of two exercise programs on proxy‐ and performance‐based measures of activities of daily living (ADLs) and to explore potential motor and cognitive mediators underlying ADL improvements in individuals with dementia.

Burrowing as a novel voluntary strength training method for mice: A comparison of various voluntary strength or resistance exercise methods

BACKGROUND Voluntary strength training methods for rodents are necessary to investigate the effects of strength training on cognition and the brain. However, few voluntary methods are available. NEW METHOD The current study tested functional and muscular effects of two novel voluntary strength training methods, burrowing (digging a substrate out of a tube) and unloaded tower climbing, in male C57Bl6 mice. To compare these two novel methods with existing exercise methods, resistance running and (non-resistance) running were included. Motor coordination, grip strength and muscle fatigue were measured at baseline, halfway through and near the end of a fourteen week exercise intervention. Endurance was measured by an incremental treadmill test after twelve weeks. RESULTS Both burrowing and resistance running improved forelimb grip strength as compared to controls. Running and resistance running increased endurance in the treadmill test and improved motor skills as measured by the balance beam test. Post-mortem tissue analyses revealed that running and resistance running induced Soleus muscle hypertrophy and reduced epididymal fat mass. Tower climbing elicited no functional or muscular changes. COMPARISON WITH EXISTING METHODS As a voluntary strength exercise method, burrowing avoids the confounding effects of stress and positive reinforcers elicited in forced strength exercise methods. Compared to voluntary resistance running, burrowing likely reduces the contribution of aerobic exercise components. CONCLUSIONS Burrowing qualifies as a suitable voluntary strength training method in mice. Furthermore, resistance running shares features of strength training and endurance (aerobic) exercise and should be considered a multi-modal aerobic-strength exercise method in mice.