Acting now on dementia prevention, intervention, and care will vastly improve living and dying for individuals with dementia and their families, and in doing so, will transform the future for society.
Hearing loss from midlife onwards is a potent and common risk for accelerated cognitive decline and dementia.1,2 However, in longitudinal observational studies, those with hearing loss who wear ...hearing aids are at reduced risk compared with those who do not and their risk becomes similar to those without hearing loss.3,4 Despite multiple sensitivity analyses considering education, cardiovascular risk, and genes showing the same results, it remained unclear whether those people with hearing aids were those who were not going to develop dementia.5 Thus, the ACHIEVE trial by Frank Lin and colleagues6 is eagerly awaited, as the first large, randomised trial of the effect of hearing aids on cognition. People in the intervention group in the ARIC sample had less 3-year cognitive decline on standardised cognitive scores than those in the health education group (difference 0·191 0·022 to 0·360; p=0·027), but there was no effect in the de novo group (difference –0·061 –0·151 to 0·028; p=0·18). ...the authors found a substantial difference in the ARIC cohort whereby the hearing intervention was associated with a 48% reduction in 3-year cognitive change compared with the control. ...we urgently need more trials in other settings, using the lessons learnt about the need to focus on purposively sampled populations at high risk of cognitive decline and dementia.
Sleep disturbances affect 38% of care home residents living with dementia. They are often treated with medication, but non-pharmacological interventions may be safer and effective yet more difficult ...to implement. In the SIESTA study (Sleep problems In dEmentia: interviews with care home STAff) we explored care home staffs' experience of managing sleep disturbances in their residents living with dementia. We conducted one-to-one semi-structured interviews in four UK care homes, and purposively recruited a maximum variation sample of 18 nurses and care assistants, who were each interviewed once. We used a topic guide and audio-recorded the interviews. Two researchers independently analysed themes from transcribed interviews. Staff used a range of techniques that often worked in improving or preventing residents' sleep disturbance. During the daytime, staff encouraged residents to eat well, and be physically active and stimulated to limit daytime sleep. In the evening, staff settled residents into dark, quiet, comfortable bedrooms often after a snack. When residents woke at night, they gave them caffeinated tea or food, considered possible pain and discomfort, and reassured residents they were safe. If residents remained unsettled, staff would engage them in activities. They used telecare to monitor night-time risk. Staff found minimising daytime napping difficult, described insufficient staffing at night to attend to reorient and guide awake residents and said residents frequently did not know it was night-time. Some common techniques, such as caffeinated drinks, may be counterproductive. Future non-pharmacological interventions should consider practical difficulties staff face in managing sleep disturbances, including struggling to limit daytime napping, identifying residents' night-time needs, day-night disorientation, and insufficient night-time staffing.
Models describing the neural correlates of biased emotion processing in depression have focused on increased activation of anterior cingulate and amygdala and decreased activation of striatum and ...dorsolateral prefrontal cortex. However, neuroimaging studies investigating emotion processing in depression have reported inconsistent results. This meta-analysis integrates these findings and examines whether emotional valence modulates such abnormalities. A systematic literature search identified 26 whole-brain and 18 region-of-interest studies. Peak coordinates and effect sizes were combined in an innovative parametric meta-analysis. Opposing effects were observed in the amygdala, striatum, parahippocampal, cerebellar, fusiform and anterior cingulate cortex, with depressed subjects displaying hyperactivation for negative stimuli and hypoactivation for positive stimuli. Anterior cingulate activity was also modulated by facial versus non-facial stimuli, in addition to emotional valence. Depressed subjects also showed reduced activity in left dorsolateral prefrontal cortex for negative stimuli and increased activity in orbitofrontal cortex for positive stimuli. Emotional valence is a moderator of neural abnormalities in depression, and therefore a critical feature to consider in models of emotional dysfunction in depression.
Depression is experienced as a persistent low mood or anhedonia accompanied by behavioural and cognitive disturbances which impair day to day functioning. However, the diagnosis is largely based on ...self-reported symptoms, and there are no neurobiological markers to guide the choice of treatment. In the present study, we examined the prognostic and diagnostic potential of the structural neural correlates of depression.
Subjects were 37 patients with major depressive disorder (mean age 43.2 years), medication-free, in an acute depressive episode, and 37 healthy individuals. Following the MRI scan, 30 patients underwent treatment with the antidepressant medication fluoxetine or cognitive behavioural therapy (CBT). Of the patients who subsequently achieved clinical remission with antidepressant medication, the whole brain structural neuroanatomy predicted 88.9% of the clinical response, prior to the initiation of treatment (88.9% patients in clinical remission (sensitivity) and 88.9% patients with residual symptoms (specificity), p = 0.01). Accuracy of the structural neuroanatomy as a diagnostic marker though was 67.6% (64.9% patients (sensitivity) and 70.3% healthy individuals (specificity), p = 0.027).
The structural neuroanatomy of depression shows high predictive potential for clinical response to antidepressant medication, while its diagnostic potential is more limited. The present findings provide initial steps towards the development of neurobiological prognostic markers for depression.
Alexithymia is a personality trait characterized by difficulties in the experience and cognitive processing of emotions. It is considered a risk factor for a range of psychiatric and neurological ...disorders. Functional neuroimaging studies investigating the neural correlates of alexithymia have reported inconsistent results. To integrate previous findings, we conducted a parametric coordinate-based meta-analysis including fifteen neuroimaging studies on emotion processing in alexithymia. During the processing of negative emotional stimuli, alexithymia was associated with a diminished response of the amygdala, suggesting decreased attention to such stimuli. Negative stimuli additionally elicited decreased activation in supplementary motor and premotor brain areas and in the dorsomedial prefrontal cortex, possibly underlying poor empathic abilities and difficulties in emotion regulation associated with alexithymia. Positive stimuli elicited decreased activation in the right insula and precuneus, suggesting reduced emotional awareness in alexithymia regarding positive affect. Independent of valence, higher (presumably compensatory) activation was found in the dorsal anterior cingulate possibly indicating increased cognitive demand. These results suggest valence-specific as well as valence-independent effects of alexithymia on the neural processing of emotions.
Abstract We performed a systematic review and meta-analysis of neural predictors of response to the most commonly used, evidence based treatments in clinical practice, namely pharmacological and ...psychological therapies. Investigations of medication-free subjects suffering from a current major depressive episode who underwent positron emission tomography (PET) or functional or structural magnetic resonance imaging (MRI) scans prior to the initiation of treatment were reviewed. Results of 20 studies from 15 independent samples were included in the functional imaging meta-analysis and 9 studies from 6 independent samples in the structural neuroimaging meta-analysis. Regional activations with prognostic value include the well replicated finding that increased baseline activity in the anterior cingulate is predictive of a higher likelihood of improvement. As well, increased baseline activation in the insula and striatum is associated with higher likelihood of a poorer clinical response. Structural neuroimaging studies indicated that a decrease in right hippocampal volume is a statistically significant predictor of poorer treatment response. Overall, the predictive information that is measurable with brain imaging techniques is both multimodal and regionally distributed as it contains functional as well as structural correlates which encompass several brain regions within a frontostriatal–limbic network. To develop clinically relevant, prognostic markers will require high predictive accuracy at the level of the individual. Predicting clinical response will help to stratify patients and to identify at an early stage those patients who may require more intensive or combined therapies. We propose that structural and functional neuroimaging show significant potential for the development of prognostic markers of clinical response in the treatment of depression.
Using hearing aids appears to reduce the excess risk from hearing loss. New evidence supports adding three modifiable risk factors—excessive alcohol consumption, head injury, and air pollution—to our ...2017 Lancet Commission on dementia prevention, intervention, and care life-course model of nine factors (less education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, and infrequent social contact). Encourage use of hearing aids for hearing loss and reduce hearing loss by protection of ears from excessive noise exposure. Examples include creating environments that have physical activity as a norm, reducing the population profile of blood pressure rising with age through better patterns of nutrition, and reducing potential excessive noise exposure.
Background
Older adults are at high risk of developing age‐related hearing loss (HL) and/or cognitive impairment. However, cognitive screening tools rely on oral administration of instructions and ...stimuli that may be impacted by HL. This systematic review aims to investigate (a) whether people with HL perform worse than those without HL on the Montreal Cognitive Assessment (MoCA), a widely used screening tool for cognitive impairment, and what the effect size of that difference is (b) whether HL treatment mitigates the impact of HL.
Method
We conducted a systematic review and meta‐analysis including studies that reported mean MoCA scores and SDs for individuals with HL.
Results
People with HL performed significantly worse on the MoCA (4 studies, N = 533) with a pooled mean difference of −1.66 points (95% confidence interval CI ‐2.74 to −0.58). There was no significant difference in MoCA score between the pre‐ vs post‐hearing intervention (3 studies, N = 75). However, sensitivity analysis in the cochlear implant studies (2 studies, N = 33) showed improvement of the MoCA score by 1.73 (95% CI 0.18 to 3.28).
Conclusion
People with HL score significantly lower than individuals with normal hearing on the standard orally administered MoCA. Clinicians should consider listening conditions when administering the MoCA and report the hearing status of the tested individuals, if known, taking this into account in interpretation or make note of any hearing difficulty during consultations which may warrant onward referral. Cochlear implants may improve the MoCA score of individuals with HL, and more evidence is required on other treatments. J Am Geriatr Soc 68:‐, 2020.
Abstract Background Reduced hippocampal volume has been consistently observed in major depressive disorder. Hippocampal volume loss is particularly evident in patients with recurrent and chronic ...depression. However, the reports in first episode depression have been mixed. Methods We performed a random effects meta-analysis to establish whether hippocampal atrophy exists from disease onset. We included magnetic resonance imaging studies of hippocampal volume in patients with first episode major depressive disorder and matched healthy controls. Results A total of 7 studies met our inclusion and exclusion criteria, representing independent observations in a total sample of 191 patients and 282 healthy controls. The cumulative analysis revealed hippocampal volume loss in patients with first episode depression relative to controls in both the left (standardised mean difference, SMD = − 0.41, 95% Confidence Interval: − 0.78;−0.03, z = − 2.14, p = 0.0321) and right (SMD = − 0.53− 0.98;−0.09, z = − 2.38, p = 0.0173) hippocampi. The average volume reduction was − 4.0% in the left and − 4.5% in the right hippocampus. Conclusions Hippocampal volume loss in first episode depression is consistent with a neurodevelopmental model of depression, advocating hippocampal structure as a potential diagnostic neurobiomarker for depression.
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