27 research outputs found
Sufficient exercise for Australians living with dementia in residential aged care facilities is lacking: An exploration of policy incoherence
Along with cognitive decline, dementia is characterised by changes in emotional control, social behaviour and physical performance.1 Individuals living with dementia often require assistance with their activities of daily living as dementia progresses.2 Requirements for higher levels of care result in more individuals with dementia living in residential aged care facilities (RACFs); up to 52% of all individuals living in RACFs have a diagnosis of dementia
Examining the concordance of retinal ganglion cell counts generated using measures of structure and function
PURPOSE: There are several indirect methods used to estimate retinal ganglion cell (RGC) count in an individual eye, but there is limited information as to the agreement between these methods. In this work, RGC receptive field (RGCâRF) count underlying a spot stimulus (0.43°, Goldmann III) was calculated and compared using three different methods. METHODS: RGCâRF count was calculated at a retinal eccentricity of 2.32âmm for 44 healthy adult participants (aged 18â58âyears, refractive error â9.75 DS to +1.75 DS) using: (i) functional measures of achromatic peripheral grating resolution acuity (PGRA), (ii) structural measures of RGCâlayer thickness (OCTâmodel, based on the method outlined by Raza and Hood) and (iii) scaling published histology density data to simulate a global expansion in myopia (HistologyâBalloon). RESULTS: Whilst average RGCâRF counts from the OCTâmodel (median 105.3, IQR 99.6â111.0) and the HistologyâBalloon model (median 107.5, IQR 97.7â114.6) were similar, PGRA estimates were approximately 65% lower (median 37.7, IQR 33.8â46.0). However, there was poor agreement between all three methods (BlandâAltman 95% limits of agreement; PGRA/OCT: 55.4; PGRA/HistologyâBalloon 59.3; OCT/HistologyâBalloon: 52.4). High intersubject variability in RGCâRF count was evident using all three methods. CONCLUSIONS: The lower PGRA RGCâRF counts may be the result of targeting only a specific subset of functional RGCs, as opposed to the coarser approach of the OCTâmodel and HistologyâBalloon, which include all RGCs, and also likely displaced amacrine cells. In the absence of a âground truthâ, direct measure of RGCâRF count, it is not possible to determine which method is most accurate, and each has limitations. However, what is clear is the poor agreement found between the methods prevents direct comparison of RGCâRF counts between studies utilising different methodologies and highlights the need to utilise the same method in longitudinal work
Temporal summation in myopia and its implications for the investigation of glaucoma
Purpose
We have previously demonstrated the upper limit of complete spatial summation (Ricco's area) to increase in non-pathological axial myopia compared to non-myopic controls. This study sought to investigate whether temporal summation is also altered in axial myopia to determine if this aspect of visual function, like in glaucoma, is influenced by reductions in retinal ganglion cell (RGC) density.
Methods
Achromatic contrast thresholds were measured for a GIII-equivalent stimulus (0.43° diameter) of six different stimulus durations (1â24 frames, 1.1â187.8âms) in 24 participants with axial myopia (mean spherical refractive error: â4.65D, range: â1.00D to â11.25D, mean age: 34.1, range: 21â57âyears) and 21 age-similar non-myopic controls (mean spherical refractive error: +0.87D, range: â0.25D to +2.00D, mean age: 31.0, range: 18â55âyears). Measurements were performed at 10° eccentricity along the 90°, 180°, 270° and 360° meridians on an achromatic 10âcd/m2 background. The upper limit of complete temporal summation (critical duration, CD) was estimated from the data with iterative two-phase regression analysis.
Results
There was no significant difference (pâ=â0.90, MannâWhitney U-test) in median CD between myopes (median: 44.3âms; IQR: 26.5, 51.2) and non-myopes (median: 41.6âms; IQR: 27.3, 48.5). Despite RGC numbers underlying the stimulus being significantly lower in the myopic group (pâ<â0.001), no relationship was observed between the CD estimate and co-localised RGC number (Pearson's râ=ââ0.13, pâ=â0.43) or ocular length (Pearson's râ=ââ0.08, pâ=â0.61).
Conclusions
Unlike spatial summation, temporal summation is unchanged in myopia. This contrasts with glaucoma where both temporal and spatial summation are altered. As such, perimetric methods optimised to test for anomalies of temporal summation may provide a means to differentiate between conditions causing only a reduced RGC density (e.g., myopia), and pathological processes causing both a reduced RGC density and RGC dysfunction (e.g., glaucoma)
Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study
Purpose:
Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom.
Methods:
Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded.
Results:
The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8â4.6) in CFS 4 vs 1â3; OR 12.4 (6.2â24.5) in CFS 8 vs 1â3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3â1.9) in CFS 4 compared to 0.2 (0.1â0.7) in CFS 8). These risks were both independent of age and dementia.
Conclusion:
We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes
Effects of physical activity on health and well-being of individuals living with a dementia in residential accommodation: a systematic review
Poster presented at 47th AAG National Conference, Adelaide, 26-28 November 2014
Measuring the effects of physical activity on individuals living with a dementia in residential accommodation: a systematic review of RCTs
Abstract of presentation from the Dementia Collaborative Research Centres\u27 (DCRC) 2014 National Dementia Research Forum, Sydney, 19 September 2014
Effects of physical exercise on health and well-being of individuals living with a dementia in nursing homes: a systematic review
Background Physical exercise interventions have benefits for older individuals and improve the health and well-being of individuals living with a dementia, specifically those living in nursing homes. Purpose Report evidence from randomized controlled trials and cluster randomized control trials that evaluated the effects of physical exercise interventions on individuals living with a dementia in nursing homes. Data sources Web of Science, Scopus, Science Direct, Academic Search Complete, Proquest Central, British Medical Journal Database, PubMed, Cochrane Library, PEDro, Informit, Informa, and Nursing Consult were searched for relevant clinical trials and snowballing of recommended studies. Study selection One reviewer screened articles on inclusion criteria and identified relevant studies. Data extraction Data extraction was performed by 1 reviewer and checked by second and third reviewers. Two authors assessed the methodological quality and risk of bias of the relevant studies. Data synthesis Twelve study populations consisting of individuals living with a dementia in nursing homes were included (n = 901). Different types of physical exercises were undertaken: multimodal (n = 6), walking (n = 5), music and movement (n = 2), and hand exercises (n = 1). The parameters of the interventions varied across the studies. Most of the studies reported significant positive effects of physical exercise on cognition, agitation, mood, mobility, and functional ability for individuals living with dementia in nursing homes. Limitations The main limitations were the heterogeneity of design, small samples, and short interventions. Conclusions There is emerging evidence that physical exercise significantly benefits individuals living with a dementia in nursing homes. Higher quality research is required adopting more rigorous methods, including longer interventions and larger samples to determine optimum parameters of the physical exercise interventions evaluated
Perimetry: a change in the rate of progress?
This special feature article will consider the utility and limitations of conventional perimetry in 2016, as well as possible ways in which the technique might be improved upon in the future