Is the incidence of dementia declining?

Action on preventative health could lower the risk of dementia for future generations, argues this report. Executive summary The world-wide projections of the prevalence of dementia in the coming decades have been a source of great concern to health systems and societies around the world. The World Alzheimer Report 2010 estimated that there were 36 million people with dementia in 2010, with an expected doubling every 20 years to nearly 115 million in 2050. These sobering figures are based on assumptions that the age-adjusted prevalence of dementia would remain constant and the population would continue to age at the current rate. The assumption that the incidence of dementia will remain stable is now being put into question. There is emerging evidence to suggest that the incidence of dementia in older individuals may be declining. It appears that this change may be recent and has possibly occurred only in the last one to two decades. It may also be restricted so far to high income countries, although data from low and middle income countries are lacking. The reasons for this change are not understood, but education, more stimulating environments and better control of vascular risk factors may have contributed. The data are still preliminary and more studies are needed to establish the extent of this change and understand its causes. It should be noted that the decline is not large enough to offset the increase in prevalence of dementia due to the ageing of the population and therefore investment and efforts to develop better treatments and care for people with dementia need to continue. The fact that dementia rates are malleable is an encouraging finding but the reduction cannot be taken for granted as gains in population health can easily be lost if societies do not remain vigilant and continually proactive. These preliminary findings provide a strong argument for large scale Government investment in dementia-prevention strategies, which should start from early life

Computer-delivered cognitive behavioural therapy: effective and getting ready for dissemination

Computer-delivered cognitive behavioural therapy (CCBT) is emerging as a promising strategy for improving access to mental health services. Randomized controlled trials have confirmed the efficacy of guided CCBT in treating depression, generalized anxiety disorder, panic disorder, social phobia, and other common mental disorders. With proper guidance, effect sizes are comparable to those obtained in face-to-face cognitive behavioural therapy, treatment is cost-effective, and preliminary data indicate that CCBT is acceptable to patients. Trials are beginning to evaluate optimal strategies for integrating CCBT within existing systems of mental health care

Dietary mineral intake and risk of Mild Cognitive Impairment: the PATH Through Life Project

Background: Higher dietary intake of potassium, calcium, and magnesium is protective against ischemic strokes while being also associated with a decreased risk of all-cause dementia. The effect of dietary iron intake on cerebral function is less clear but iron is also implicated in Alzheimer neuropathology. The aim of this study was to investigate whether dietary intake of these minerals was also associated with increased risk of Mild Cognitive Impairment (amnestic) and other Mild Cognitive Disorders. Methods: Associations between dietary mineral intake and risk of MCI/MCD was assessed in cognitively healthy individuals (n=1406, 52% female, mean age 62.5 years) living in the community who were followed up over 8 years. Relative risk was assessed with Cox hazard ratios after controlling for health and socio-demographic covariates. Results: Higher magnesium intake was associated with a reduced risk of developing MCI/MCD (MCI:Hazard Ratio (HR) 0.07,95% Confidence Interval (CI) 0.01-0.56, p=0.013; MCD: HR 0.47,95%CI 0.22-.99,p=0.046) in multivariate analyses. Higher intake of potassium (MCI: HR 1.09,95%CI 1.01-1.17,p=0.028; MCD: HR 1.05,95%CI 0.99-1.10,p=.107) and iron (MCI: HR 1.54,95%CI 1.03-2.29,p=0.034) was associated with an increased risk of developing MCI/MCD. Conclusions: These findings suggest that dietary intake of minerals known to be implicated in biological processes associated with vascular and Alzheimer’s pathology may contribute to disease progression earlier in the disease process and require further attention.The study was supported by NHMRC of Australia Nos.973302,179805,157125. Nicolas Cherbuin is funded by ARC Future Fellowship No.120100227and Kaarin J. Anstey by NHMRC Fellowship No.1002560. This research has been supported by the Australian Research Council and the NHMRC of Australia. The statistical analyses were conducted by Cherbuin

Transcranial direct current stimulation - what is the evidence for its efficacy and safety?

Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, has emerged in the past decade as a useful investigative and therapeutic technique. A number of recent studies suggest that tDCS is safe and may be efficacious in the treatment of a variety of psychiatric and neurological disorders, including major depressive disorder, chronic neuropathic pain, and stroke. More evidence is necessary, however, before it can be recommended for general clinical application

Cognitive Deficits Are Associated with Frontal and Temporal Lobe White Matter Lesions in Middle-Aged Adults Living in the Community

BACKGROUND The association between brain white matter lesions and cognitive impairment in old age is well established. However, little is known about this association in midlife. As this information will inform policy for early preventative healthcare initiatives, we investigated non-periventricular frontal, temporal, parietal and occipital lobe white matter hyperintensities (WMH) in relation to cognitive function in 428 (232 women) community-dwelling adults aged 44 to 48 years. RESULTS Frontal white matter lesions were significantly associated with greater intraindividual RT variability in women, while temporal WMH were associated with face recognition deficits in men. Parietal and occipital lobe lesions were unrelated to cognitive performance. These findings did not differ when education and a range of health variables, including vascular risk factors, were taken into account. CONCLUSION Gender differences in WMH-cognition associations are discussed, and we conclude that small vessel disease is present in midlife and has functional consequences which are generally not recognized. Preventative strategies should, therefore, begin early in life.David Bunce's collaboration in this work was supported by the Leverhulme Trust and the British Academy. The study was funded by NHMRC of Australia Unit Grant No. 973302, Program Grant No. 179805, NHMRC project grant No. 157125, grants from the Australian Rotary Health Research Fund and the Australian Brewers Foundation. Nicolas Cherbuin is funded by NHMRC Research Fellowship No. 471501. Kaarin Anstey is funded by NHMRC Research Fellowship No. 366756. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript

Why do women have more white matter hyperintensities? Sex differences in the extent, aetiology and consequences of leukoaraiosis

Unlike other age-related brain changes, white matter hyperintensities (WMHs) are reported to be more severe in older women than men. This study examined a large epidemiological sample of middle-aged individuals to determine sex differences in WMHs, and investigated their differential functional consequences and aetiological factors to explain the sex differences

The falls efficacy scale international (FES-I): a comprehensive longitudinal validation study

Method: five hundred community-dwelling older people (70-90 years) were assessed on the FES-I in conjunction with demographic, physiological and neuropsychological measures at baseline and at 12 months. Falls were monitored monthly and fear of falling every 3 months. Results: the overall structure and measurement properties of both FES-I scales, as evaluated with item response theory, were good. Discriminative ability on physiological and neuropsychological measures indicated excellent validity, both at baseline (n = 500, convergent validity) and at 1-year follow-up (n = 463, predictive validity). The longitudinal follow-up suggested that FES-I scores increased over time regardless of any fall event, with a trend for a stronger increase in FES-I scores when a person suffered multiple falls in a 3-month period. Additionally, using receiver-operating characteristic (ROC) curves, cut-points were defined to differentiate between lower and higher levels of concern. Conclusions: the current study builds on the previously established psychometric properties of the FES-I. Both scales have acceptable structures, good validity and reliability and can be recommended for research and clinical purposes. Future studies should explore the FES-I's responsiveness to change during intervention studies and confirm suggested cut-points in other settings, larger samples and across different cultures

The role of concern about falling on stepping performance during complex activities

Background There is limited understanding of the underlying mechanisms explaining the role of concern about falling on fall risk in older people. Anxiety is known to interact with cognitive resources and, as people get older, they require more cognitive resources to maintain balance. This might affect an individual's ability to perform cognitive-motor tasks concurrently. The aim of this study was to investigate the effect of a visuospatial dual-task on stepping performance in older people with and without concern about falling and the impact of repeating this task in those with high concern about falling. Methods Three-hundred-eight community-dwelling older people, aged 70 to 90 years old, participated in the study. Participants were asked to perform a Choice Stepping Reaction Time (CSRT) task in two conditions; once without any other tasks (single task condition), and once while simultaneously performing a visuospatial task (dual-task condition). Participants were asked to rate their levels of concern and confidence specifically related to each of the 25 stepping trials (before/after). We also measured general concern about falling, affect, and sensorimotor and cognitive functioning. Results Total stepping reaction times increased when participants also performed the visuospatial task. The relation between general concern about falling and stepping reaction time, was affected by sensorimotor and executive functioning. Generalised linear mixed models showed that the group with moderate to high levels of general concern about falling had slower total stepping reaction times than those with lower levels of concern about falling, especially during the dual-task condition. Individuals with greater general concern about falling showed reduced confidence levels about whether they could do the stepping tasks under both conditions. Repeatedly performing the stepping task reduced the immediate task-specific concern about falling levels and increased confidence in all participants. Conclusions These findings reveal that people with higher general concern about falling experienced more difficulties during a dual-task condition than people with lower levels of concern. Of further interest, better sensorimotor and cognitive functioning reduced this effect. Graded exposure has potential to reduce concern about falling during fear-evoking activities, especially in conjunction with therapies that improve balance, mood and cognitive function