The feasibility of a multidomain dementia risk reduction randomised controlled trial for people experiencing cognitive decline: the Body, Brain, Life for Cognitive Decline (BBL-CD)

OBJECTIVES

To evaluate the feasibility of a proof-of-concept multidomain dementia risk reduction intervention.

METHOD

An 8-week, parallel-group RCT, focused on increasing adherence to lifestyle domains of Mediterranean diet (MeDi), Physical Activity (PA), and Cognitive Engagement (CE). Feasibility was evaluated against the Bowen Feasibility Framework objectives of: Acceptability of the intervention, compliance with the protocol, and efficacy of the intervention to change behaviour in the three domains of interest.

RESULTS

High acceptability of the intervention was demonstrated through a participant retention rate of 80.7% (Intervention: 84.2%; Control: 77.4%). Compliance to the protocol was strong with 100% of participants completing all educational modules and all MeDi and PA components, with 20% compliance for CE. Linear mixed models demonstrated efficacy to change behaviour through significant effects of adherence to MeDi (χ2 = 16.75, df = 3, p < .001) and CE (χ2 = 9.83, df = 3, p =.020), but not PA (χ2 = 4.48, df = 3, p =.211).

CONCLUSION

Overall the intervention was shown to be feasible. Recommendations for future trials in this area are: The implementation of practical, one-on-one sessions as they are more effective than passive education at eliciting behaviour change; use of booster sessions to increase likelihood of lifestyle changes being sustained; and collection of qualitative data to identify barriers to change.

Validation of the CogDrisk Instrument as Predictive of Dementia in Four General Community-Dwelling Populations

BACKGROUND

Lack of external validation of dementia risk tools is a major limitation for generalizability and translatability of prediction scores in clinical practice and research.

OBJECTIVES

We aimed to validate a new dementia prediction risk tool called CogDrisk and a version, CogDrisk-AD for predicting Alzheimer's disease (AD) using cohort studies.

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Four cohort studies were identified that included majority of the dementia risk factors from the CogDrisk tool. Participants who were free of dementia at baseline were included. The predictors were component variables in the CogDrisk tool that include self-reported demographics, medical risk factors and lifestyle habits. Risk scores for Any Dementia and AD were computed and Area Under the Curve (AUC) was assessed. To examine modifiable risk factors for dementia, the CogDrisk tool was tested by excluding age and sex estimates from the model.

RESULTS

The performance of the tool varied between studies. The overall AUC and 95% CI for predicting dementia was 0.77 (0.57, 0.97) for the Swedish National study on Aging and Care in Kungsholmen, 0.76 (0.70, 0.83) for the Health and Retirement Study - Aging, Demographics and Memory Study, 0.70 (0.67,0.72) for the Cardiovascular Health Study Cognition Study, and 0.66 (0.62,0.70) for the Rush Memory and Aging Project.

CONCLUSIONS

The CogDrisk and CogDrisk-AD performed well in the four studies. Overall, this tool can be used to assess individualized risk factors of dementia and AD in various population settings.

Cost-Effectiveness of Dementia Prevention Interventions

BACKGROUND

Assessment of cost-effectiveness of interventions to address modifiable risk factors associated with dementia requires estimates of long-term impacts of these interventions which are rarely directly available and must be estimated using a range of assumptions.

OBJECTIVES

To test the cost-effectiveness of dementia prevention measures using a methodology which transparently addresses the many assumptions required to use data from short-term studies, and which readily incorporates sensitivity analyses.

DESIGN

We explore an approach to estimating cost-effective prices which uses aggregate data including estimated lifetime costs of dementia, both financial and quality of life, and incorporates a range of assumptions regarding sustainability of short- term gains and other parameters.

SETTING

The approach is addressed in the context of the theoretical reduction in a range of risk factors, and in the context of a specific small-scale trial of an internet-based intervention augmented with diet and physical activity consultations.

MEASUREMENTS

The principal outcomes were prices per unit of interventions at which interventions were cost-effective or cost-saving.

RESULTS

Taking a societal perspective, a notional intervention reducing a range of dementia risk-factors by 5% was cost-effective at $A460 per person with higher risk groups at $2,148 per person. The on-line program costing $825 per person was cost-effective at $1,850 per person even if program effect diminished by 75% over time.

CONCLUSIONS

Interventions to address risk factors for dementia are likely to be cost-effective if appropriately designed, but confirmation of this conclusion requires longer term follow-up of trials to measure the impact and sustainability of short-term gains.

Oxidative stress, inflammation and risk of neurodegeneration in a population sample

BACKGROUND AND PURPOSE

Inflammation and oxidative stress (OS) have been clearly linked to neurodegeneration. However, studies investigating the associations between peripheral markers of inflammation and cognitive decline have produced mixed results. This is possibly due to the fact that markers are typically tested individually despite the fact that biologically they function interactively. Thus, the aim of this study was to investigate the association between a combination of OS/inflammation markers and outcomes including mild cognitive impairment (MCI) diagnosis, cognitive decline and hippocampal atrophy.

METHODS

Oxidative stress/inflammation status was assessed in 380 older community-living individuals. Thirteen blood markers were assayed. Principal component analysis (PCA) of all markers was conducted to identify the more salient inflammatory components. Associations between significant principal components, MCI diagnosis, previous change in Mini-Mental State Examination (MMSE) score and hippocampal atrophy were investigated through logistic and linear multiple regression.

RESULTS

Two factors (PC1 and PC2) reflecting predominantly broad pro-inflammatory activity and two factors (PC3 and PC4) reflecting predominantly OS activity were identified by PCA analysis. PC3 and PC4 were predictive of MCI. PC3 was also predictive of prior MMSE change. PC1, PC2 and PC3 were significantly associated with hippocampal atrophy.

CONCLUSIONS

Combined analysis of complex and interacting biomarkers revealed a protective association between antioxidant activity and MCI that is consistent with lifestyle factors shown to reduce risk of cognitive decline. OS and broad systemic inflammation were also found to be associated with hippocampal atrophy further highlighting the benefits of the PCA methodology applied in this study.

Subjective memory complaints and incident dementia in a high risk older adult hypertensive population

BACKGROUND

there is a growing body of evidence demonstrating an association between subjective memory complaints (SMC) and an increased risk of incident cognitive decline or dementia. To date this has not been examined in hypertensive older adults, a prevalent and growing population group at high risk of cognitive decline.

METHODS

using data from participants in the Hypertension in the Very Elderly Trial cohort the association between baseline SMC and incident cognitive decline and dementia was examined using Cox proportional hazard regression. Cognitive function was assessed using the Mini-Mental State Exam and diagnoses of dementia were made using standard diagnostic criteria. SMC was assessed by the question 'do you feel that you have more problems with memory than most?' Analyses were rerun to examine the associations by level of baseline cognitive function, to evaluate the role of SMC by dementia type and by sex.

RESULTS

baseline SMC were associated with an increased risk of developing any dementia (hazard ratio (HR)1.63 (95% confidence intervals (CI): 1.18:2.25)), Alzheimer's disease (HR1.59 (95% CI: 1.08:2.34)) and vascular dementia (HR2.05 (95% CI: 1.19:3.54)). Similar patterns were seen across all levels of baseline MMSE but were strongest in those with scores of 25-27. There were no clear differences by sex.

DISCUSSION

a positive report of SMC assessed by a single question in an older adult with hypertension raises the possibility of increased risk of incident dementia. As such its use may be a useful addition to the repertoire of the general practitioner and geriatrician when assessing older adults.

Combining Geospatial Analysis with Dementia Risk Utilising General Practice Data: A Systematic Review

Geographical information systems (GIS) and geospatial analysis techniques will help to identify significant dementia risk clusters (hotspots) across communities and will enable policy makers to target prevention interventions to the right place. This review synthesises the published literature on geospatial analysis techniques for quantifying and mapping dementia risk, and reviews available dementia risk assessment tools. A systematic literature review was undertaken in four medical and life sciences databases (PubMed, Cochrane Central, Embase, and Web of Sciences) from their inception to March 2017 for all articles relating to dementia. The search terms included: 'dementia', 'Alzheimer's disease', 'general practice database', 'family physician', 'AD risk assessment tools', 'Geographical Information Systems' and 'geospatial analysis', 'geographical variation' and 'spatial variation'. To date, most geospatial studies on dementia have been carried out retrospectively using population based data. An alternative approach is utilisation of a rich source of general practice (family physician) databases to predict dementia risk based on available dementia risk assessment tools. In conclusion, the estimated risks of dementia can thus be geo-attributed and mapped at a small scale using geographical information systems and geospatial analysis techniques to identify dementia risk clusters across the communities and refine our understanding of the interaction between socio-demographic and environmental factors, and dementia risk clusters.   .

Oversimplification of Dementia Risk Reduction Messaging Is a Threat to Knowledge Translation in Dementia Prevention Research

The evidence for specific risk factors for Alzheimer’s disease, vascular dementia and all cause dementia is increasing rapidly in quantity and quality. This has enabled the compilation of risk assessment tools for Alzheimer’s disease (1), and their validation (2). It has also supported the promulgation of public health messaging about dementia risk reduction or dementia prevention. In general these developments are strong advances in the field of dementia prevention. However, the oversimplification of the findings and possible over-or mis-interpretation of their meaning, poses risks to accurate and effective knowledge translation in this field. Lack of balance in the interpretation of evidence on risk factors for dementia may lead to trials of interventions for dementia prevention that are ineffective. This will waste resources and create pessimism about dementia prevention research. Two potential problems that may occur when translating evidence from observational research into prescriptions for prevention are identified here. The first is the generalisation of specific findings about risk factors either to multiple types of dementia or to multiple populations, when the evidence is in fact relevant to specific populations or outcomes. The second is the inference that reversal of a risk factor will lead to prevention, without knowledge of the threshold at which a factor becomes a ‘risk’, or evidence that reversal of the risk factor also reverses neuropathological processes instigated or caused by the risk factor.

Body mass index is associated with cortical thinning with different patterns in mid- and late-life

OBJECTIVE

High BMI at midlife is associated with increased risk of dementia as well as faster decline in cognitive function. In late-life, however, high BMI has been found to be associated with both increased and decreased dementia risk. The objective of this study was to investigate the neural substrates of this age-related change in body mass index (BMI) risk.

METHODS

We measured longitudinal cortical thinning over the whole brain, based on magnetic resonance imaging scans for 910 individuals aged 44-66 years at baseline. Subjects were sampled from a large population study (PATH, Personality and Total Health through Life). After attrition and exclusions, the final analysis was based on 792 individuals, including 387 individuals aged 60-66 years and 405 individuals aged 44-49 years. A mixed-effects model was used to test the association between cortical thinning and baseline BMI, as well as percentage change in BMI.

RESULTS

Increasing BMI was associated with increased cortical thinning in posterior cingulate at midlife (0.014 mm kg^-1 m^-2, confidence interval; CI=0.005, 0.023, P<0.05 false discovery rate (FDR) corrected). In late-life, increasing BMI was associated with reduced cortical thickness, most prominently in the right supramarginal cortex (0.010 mm kg^-1 m^-2, CI=0.005-0.016, P<0.05 FDR corrected), as well as frontal regions. In late-life, decreasing BMI was also associated with increased cortical thinning, including right caudal middle frontal cortex (0.014 mm kg^-1 m^-2 (CI=0.006-0.023, P<0.05 FDR corrected).

CONCLUSIONS

The pattern of cortical thinning-in association with increasing BMI at both midlife and late-life-is consistent with known obesity-related dementia risk. Increased cortical thinning in association with decreasing BMI at late-life may help explain the 'obesity paradox', where high BMI in midlife appears to be a risk factor for dementia, but high BMI in late-life appears, at times, to be protective.

Anxiety and comorbid depression following traumatic brain injury in a community-based sample of young, middle-aged and older adults

BACKGROUND

Anxiety is common following a traumatic brain injury (TBI), but who is most at risk, and to what extent, is not well understood.

METHODS

Longitudinal data from a randomly-selected community sample (Wave 1: 7397, Wave 2: 6621 and Wave 3: 6042) comprising three adult cohorts (young: 20-24 years of age, middle-aged: 40-44, older: 60-64), were analysed. The association between TBI history, anxiety and comorbid depression was assessed, controlling for age, sex, marital/employment status, medical conditions, recent life events, alcohol consumption, social support and physical activity.

RESULTS

Thirteen percent of the sample had sustained a TBI by Wave 3, 35% of whom had sustained multiple TBIs. Cross-sectional analyses revealed that clinically-significant anxiety was more common in people who had sustained a TBI. Longitudinal analyses demonstrated an increased risk of anxiety post-TBI, even after controlling for potential demographic, health and psychosocial confounds. Anxiety was more common than depression, although 10% of those with a TBI experienced comorbid anxiety/depression.

LIMITATIONS

TBIs were not medically confirmed and anxiety and depression were only assessed every four years by self-report, rather than clinical interview. Sample attrition resulted in the retention of healthier individuals at each wave.

CONCLUSIONS

TBIs are associated with a lifelong increased risk of experiencing clinically-significant anxiety, highlighting the chronic nature of TBI sequelae. Positive lifestyle changes (e.g., increasing physical activity, reducing alcohol consumption) may decrease the risk of anxiety problems in the early years after a TBI. Comorbid anxiety and depression was common, indicating that both should be monitored and treated.

Association of AKAP6 and MIR2113 with cognitive performance in a population-based sample of older adults

Genetic factors make a substantial contribution to inter-individual variability in cognitive function. A recent meta-analysis of genome-wide association studies identified two loci, AKAP6 and MIR2113, that are associated with general cognitive function. Here, we extend this previous research by investigating the association of MIR2113 and AKAP6 with baseline and longitudinal non-linear change across a broad spectrum of cognitive domains in a community-based cohort of older adults without dementia. Two single nucleotide polymorphisms (SNPs), MIR211-rs10457441 and AKAP6-rs17522122 were genotyped in 1570 non-demented older Australians of European ancestry, who were examined up to 4 times over 12 years. Linear mixed effects models were used to examine the association between AKAP6 and MIR2113 with cognitive performance in episodic memory, working memory, vocabulary, perceptual speed and reaction time at baseline and with linear and quadratic rates of change. AKAP6-rs17522122*T was associated with worse baseline performance in episodic memory, working memory, vocabulary and perceptual speed, but it was not associated with cognitive change in any domain. MIR2113-rs10457441*T was associated with accelerated decline in episodic memory. No other associations with baseline cognitive performance or with linear or quadratic rate or cognitive changes were observed for this SNP. These results confirm the previous finding that AKAP6 is associated with performance across multiple cognitive domains at baseline but not with cognitive decline, while MIR2113 primarily affects the rate at which memory declines over time.

The metabolic syndrome and cancer: Is the metabolic syndrome useful for predicting cancer risk above and beyond its individual components?

AIMS

The metabolic syndrome (MetS) is a risk factor for cancer. However, it is not known if the MetS confers a greater cancer risk than the sum of its individual components, which components drive the association, or if the MetS predicts future cancer risk.

MATERIALS AND METHODS

We linked 20,648 participants from the Australian and New Zealand Diabetes and Cancer Collaboration with complete data on the MetS to national cancer registries and used Cox proportional hazards models to estimate associations of the MetS, the number of positive MetS components, and each of the five MetS components separately with the risk for overall, colorectal, prostate and breast cancer. Hazard ratios (HR) and 95% confidence intervals (95%CI) are reported. We assessed predictive ability of the MetS using Harrell's c-statistic.

RESULTS

The MetS was inversely associated with prostate cancer (HR 0.85; 95% CI 0.72-0.99). We found no evidence of an association between the MetS overall, colorectal and breast cancers. For those with five positive MetS components the HR was 1.12 (1.02-1.48) and 2.07 (1.26-3.39) for overall, and colorectal cancer, respectively, compared with those with zero positive MetS components. Greater waist circumference (WC) (1.38; 1.13-1.70) and elevated blood pressure (1.29; 1.01-1.64) were associated with colorectal cancer. Elevated WC and triglycerides were (inversely) associated with prostate cancer. MetS models were only poor to moderate discriminators for all cancer outcomes.

CONCLUSIONS

We show that the MetS is (inversely) associated with prostate cancer, but is not associated with overall, colorectal or breast cancer. Although, persons with five positive components of the MetS are at a 1.2 and 2.1 increased risk for overall and colorectal cancer, respectively, and these associations appear to be driven, largely, by elevated WC and BP. We also demonstrate that the MetS is only a moderate discriminator of cancer risk.

The utility of estimating population-level trajectories of terminal wellbeing decline within a growth mixture modelling framework

PURPOSE

Mortality-related decline has been identified across multiple domains of human functioning, including mental health and wellbeing. The current study utilised a growth mixture modelling framework to establish whether a single population-level trajectory best describes mortality-related changes in both wellbeing and mental health, or whether subpopulations report quite different mortality-related changes.

METHODS

Participants were older-aged (M = 69.59 years; SD = 8.08 years) deceased females (N = 1,862) from the dynamic analyses to optimise ageing (DYNOPTA) project. Growth mixture models analysed participants' responses on measures of mental health and wellbeing for up to 16 years from death.

RESULTS

Multi-level models confirmed overall terminal decline and terminal drop in both mental health and wellbeing. However, modelling data from the same participants within a latent class growth mixture framework indicated that most participants reported stability in mental health (90.3 %) and wellbeing (89.0 %) in the years preceding death.

CONCLUSIONS

Whilst confirming other population-level analyses which support terminal decline and drop hypotheses in both mental health and wellbeing, we subsequently identified that most of this effect is driven by a small, but significant minority of the population. Instead, most individuals report stable levels of mental health and wellbeing in the years preceding death.

Online memory screening--are older adults interested and can it work?

Subjective memory concerns are common in older adults and may prompt the use of web-based cognitive screening. Websites which purport to provide memory screening are numerous and can influence health behaviours; however there is currently limited evidence regarding their validity. The current research aims to assess potential user's attitudes and motivations regarding online cognitive screening and to evaluate the preliminary evidence for the feasibility and validity of two subjective online cognitive measures. The sample consisted of community-based older adults, 30 with, and 30 without, memory concerns. Participants rated their likelihood of their accessing online cognitive screening and gave rationales. Participants' performance on objective pen and paper measures of cognition was compared to performance on subjective online screening measures. The majority of participants indicated they would access online cognitive screening. A total of 100% of participants were able to use the online tools without assistance. None of the online measures was positively associated with the pen and paper screening measures. Anxiety and depression were significantly associated with subjective memory concerns. This study provided no supporting evidence for the validity of either subjective online screening measure assessed. Anxiety and depression were significantly associated with subjective cognition, indicating that, although they may not predict objective cognition, complaints about memory in older adults should be taken seriously by health professionals.

Body mass index in midlife and late-life as a risk factor for dementia: a meta-analysis of prospective studies

The relationship between body mass index (BMI) (in midlife and late-life) and dementia was investigated in meta-analyses of 16 articles reporting on 15 prospective studies. Follow-ups ranged from 3.2 to 36.0 years. Meta-analyses were conducted on samples including 25 624 participants evaluated for Alzheimer's disease (AD), 15 435 participants evaluated for vascular dementia (VaD) and 30 470 followed for any type of dementia (Any Dementia). Low BMI in midlife was associated with 1.96 [95% confidence interval (CI): 1.32, 2.92] times the risk of developing AD. The pooled relative risks for AD, VaD and Any Dementia for overweight BMI in midlife compared with normal BMI were 1.35 (95% CI:1.19, 1.54), 1.33 (95% CI: 1.02, 1.75) and 1.26 (95% CI: 1.10, 1.44), respectively. The pooled relative risks of AD and Any Dementia for obese BMI in midlife compared to normal BMI were 2.04 (95% CI: 1.59, 2.62) and 1.64 (95% CI: 1.34, 2.00), respectively. Continuous BMI in late-life was not associated with dementia. Small numbers of studies included in pooled analyses reduce generalizability of findings, and emphasize the need for publication of additional findings. We conclude that underweight, overweight and obesity in midlife increase dementia risk. Further research evaluating late-life BMI and dementia is required.

Health literacy of older drivers and the importance of health experience for self-regulation of driving behaviour

This study provides much needed information on the education level of older drivers regarding the impact of health conditions and medications on personal driving safety, where they source this information, and how this knowledge influences self-regulation of driving. Random and convenience sampling secured 322 Australian drivers (63.9% males) aged 65 years and over (M = 77.35 years, SD = 7.35) who completed a telephone interview. The majority of respondents (86%) had good knowledge about health conditions (health knowledge) and driving safety, however more than 50% was classified as having poor knowledge on the effects of certain medications (medication knowledge) and driving safety. Poorer health knowledge was associated with a reduced likelihood of driving over 100 km in adjusted models. Being older and having more than one medical condition was found to increase the likelihood of self-regulation of driving. Results indicate that health knowledge was less important for predicting driving behaviour than health experience. Of great interest was that up to 85.7% of respondents reported not receiving advice about the potential impact of their medical condition and driving from their doctor. The findings indicate a need for improved dissemination of evidence-based health information and education for older drivers and their doctors.

Psychological distress and visual functioning in relation to vision-related disability in older individuals with cataracts

OBJECTIVE

To determine whether demographic, health status and psychological functioning measures, in addition to impaired visual acuity, are related to vision-related disability.

METHODS

Participants were 105 individuals (mean age=73.7 years) with cataracts requiring surgery and corrected visual acuity in the better eye of 6/24 to 6/36 were recruited from waiting lists at three public out-patient ophthalmology clinics. Visual disability was measured with the Visual Functioning-14 survey. Visual acuity was assessed using better and worse eye logMAR scores and the Melbourne Edge Test (MET) for edge contrast sensitivity. Data relating to demographic information, depression, anxiety and stress, health care and medication use and numbers of co-morbid conditions were obtained.

RESULTS

Principal component analysis revealed four meaningful factors that accounted for 75% of the variance in visual disability: recreational activities, reading and fine work, activities of daily living and driving behaviour. Multiple regression analyses determined that visual acuity variables were the only significant predictors of overall vision-related functioning and difficulties with reading and fine work. For the remaining visual disability domains, non-visual factors were also significant predictors. Difficulties with recreational activities were predicted by stress, as well as worse eye visual acuity, and difficulties with activities of daily living were associated with self-reported health status, age and depression as well as MET contrast scores. Driving behaviour was associated with sex (with fewer women driving), depression, anxiety and stress scores, and MET contrast scores.

CONCLUSION

Vision-related disability is common in older individuals with cataracts. In addition to visual acuity, demographic, psychological and health status factors influence the severity of vision-related disability, affecting recreational activities, activities of daily living and driving.

The development and validation of two complementary measures of drivers' hazard perception ability

Hazard perception in driving involves a number of different processes. This paper reports the development of two measures designed to separate these processes. A Hazard Perception Test was developed to measure how quickly drivers could anticipate hazards overall, incorporating detection, trajectory prediction, and hazard classification judgements. A Hazard Change Detection Task was developed to measure how quickly drivers can detect a hazard in a static image regardless of whether they consider it hazardous or not. For the Hazard Perception Test, young novices were slower than mid-age experienced drivers, consistent with differences in crash risk, and test performance correlated with scores in pre-existing Hazard Perception Tests. For drivers aged 65 and over, scores on the Hazard Perception Test declined with age and correlated with both contrast sensitivity and a Useful Field of View measure. For the Hazard Change Detection Task, novices responded quicker than the experienced drivers, contrary to crash risk trends, and test performance did not correlate with measures of overall hazard perception. However for drivers aged 65 and over, test performance declined with age and correlated with both hazard perception and Useful Field of View. Overall we concluded that there was support for the validity of the Hazard Perception Test for all ages but the Hazard Change Detection Task might only be appropriate for use with older drivers.

Reproductive period and cognitive function in a representative sample of naturally postmenopausal women aged 60–64 years

BACKGROUND

Greater lifetime estrogen exposure has been postulated to result in better cognition in later life, particularly in the area of verbal memory. In women, the highest levels of endogenous estrogen occur during their reproductive period, between menarche and menopause.

OBJECTIVE

To investigate the association between reproductive period and cognition.

METHODS

The sample consisted of 760 naturally postmenopausal women aged 60-64 years (mean age 62.5 +/- 1.5 years) participating in the PATH Through Life Study who were randomly drawn from the population of Canberra, Australia. Participants were administered a verbal learning test (immediate recall and 1-minute delay), the Mini-Mental State Examination (MMSE), digit span backwards, the Symbol-Digit Modalities Test and simple and choice reaction time tests.

RESULTS

There were no significant associations detected between reproductive period and performance on any of the cognitive tests, either before or after controlling for potential confounding variables.

CONCLUSIONS

Reproductive period, a surrogate measure of endogenous estrogen exposure, had no detectable effect on cognitive performance in this sample.

Pulmonary function, cognitive impairment and brain atrophy in a middle-aged community sample

OBJECTIVE

To determine the relationship of lung function to brain anatomical parameters and cognitive function and to examine the mediating factors for any relationships.

METHODS

A random sub-sample of 469 persons (men = 252) aged 60-64 years from a larger community sample underwent brain magnetic resonance imaging scans and pulmonary function tests (forced vital capacity, FVC, forced expiratory volume in the first second, FEV(1)). Subjects were assessed for global cognitive function, episodic memory, working memory, information processing speed, fine motor dexterity and grip strength. The magnetic resonance imaging scans were analysed for overall brain atrophy, subcortical atrophy (ventricle-to-brain ratio, VBR), hippocampal volume, and white matter hyperintensity (WMH) volume.

RESULTS

FEV(1) had a significant negative correlation with overall brain atrophy and VBR in men. The FEV(1)/FVC ratio had a significant correlation with WMHs in both men and women. In regression models that controlled for sex, age, height, level of activity, smoking, chronic respiratory disease and education, FEV(1) and FVC were significant predictors of VBR but no other structural brain measure. Pulmonary function was also significantly related to information processing speed and fine motor dexterity. Male subjects with chronic respiratory disease had more deep WMHs. Path analyses to examine if structural measures mediated between lung function and cognition, and whether markers of inflammation and oxidative stress or cortisol mediated between lung function and brain measures were negative.

CONCLUSIONS

Decreased lung function is related to poorer cognitive function and increased subcortical atrophy in mid-adult life. Presence of chronic respiratory disease may be related to deep WMHs in men.

Behavioural and cognitive behavioural therapy for obsessive compulsive disorder in children and adolescents

BACKGROUND

While behavioural or cognitive-behavioural therapy (BT/CBT) is recommended as the psychotherapeutic treatment of choice for children and adolescents with obsessive-compulsive disorder (OCD), the application of BT/CBT to paediatric OCD may not be straightforward.

OBJECTIVES

This review examines the overall efficacy of BT/CBT for paediatric OCD, its relative efficacy against psychopharmacology and whether there are benefits in using BT/CBT combined with medication.

SEARCH STRATEGY

We searched CCDANCTR-Studies and CCDANCTR-References (searched on 5/8/2005), MEDLINE, EMBASE, PsycINFO, the reference lists of all selected studies and handsearched journals specifically related to behavioural treatment of OCD.

SELECTION CRITERIA

Included studies were randomised controlled trials or quasi-randomised trials with participants who were 18 years of age or younger and had a diagnosis of OCD, established by clinical assessment or standardised diagnostic interview. Reviewed studies included the standard behavioural or cognitive-behavioural techniques, either alone or in combination, compared with wait-list or pill placebo.

DATA COLLECTION AND ANALYSIS

The quality of selected studies was assessed by two independent reviewers. The primary outcomes comprised of endpoint scores on the gold standard clinical outcome measure of OCD symptoms, distress and interference (CY-BOCS) and endpoint OCD status.

MAIN RESULTS

Four studies with 222 participants were considered eligible for inclusion and for data extraction. Two studies showed significantly better post-treatment functioning and reduced risk of continuing with OCD at post-treatment for the BT/CBT group compared to placebo or wait-list comparisons. We suggested that the POTS 2004 result, equal to a difference of about eight points on the CY-BOCS, represented the best available estimate for the efficacy of BT/CBT relative to no treatment. (WMD -7.50; 95% CI -11.55, -3.45). Pooled evidence from two trials indicated that the efficacy of BT/CBT and medication did not differ significantly (WMD -3.87; 95% CI -8.15, 0.41). There was evidence of the benefit of combined BT/CBT and medication compared to medication alone (WMD -4.55; 95% CI -7.40, -1.70), but not relative to BT/CBT alone (WMD -2.80; 95% CI -7.55, 1.95). The rates of drop out suggested BT/CBT is an acceptable treatment to child and adolescent patients and their families.

AUTHORS' CONCLUSIONS

Although only based on a small number of studies, behavioural or cognitive-behaviour therapy appears to be a promising treatment for OCD in children and adolescents. It can lead to better outcomes when combined with medication compared to medication alone. Additional trials are needed to confirm these findings. In the interim, consideration should be given to the ways in which BT/CBT might be made more widely available as a treatment for OCD in children and adolescents.

Factors distinguishing suicide attempters from suicide ideators in a community sample: social issues and physical health problems

BACKGROUND

Few studies have focused on factors that uniquely distinguish suicide attempters from suicide ideators. This study assesses prevalence of suicide attempts among suicide ideators within a community sample; explores demographics, employment status, mental and physical health conditions, personality, life stresses and social environment as factors that may distinguish these groups; examines effects of age and gender upon suicide attempts and associated factors; and investigates the increase in suicide attempts when multiple factors related to this behaviour are present.

METHOD

Data were drawn from the PATH Through Life Project, a community survey of 7485 people in Canberra, Australia. A subsample of 522 suicide ideators were used for this study.

RESULTS

Logistic regression was used to identify factors associated with suicide attempts. Physical medical conditions (OR 1.95) and negative interactions with friends (OR 1.20) were associated with an increased likelihood of suicide attempts among suicide ideators. Age and gender interaction effects for suicide attempts were found involving physical medical condition and mastery among men (OR 3.78 and 0.83 respectively) and not being employed for those aged 40-44 years (OR 8.94). A cumulative effect was found when multiple factors associated with suicide attempts were present, and the probability of an attempt was significantly elevated.

CONCLUSIONS

Factors distinguishing those who attempt suicide from suicide ideators involve being unemployed, physical ill health and relationship difficulties. Contrary to expectation, this study found that ideators and attempters experience comparable levels of depression and anxiety.

Age group differences in psychological distress: the role of psychosocial risk factors that vary with age

BACKGROUND

There is continuing controversy about how age affects depression and anxiety, with a lack of consistent results across studies. Two reasons for this inconsistency are age bias in measures and different patterns of exposure to risk factors across age groups in various studies.

METHOD

Data on anxiety and depression symptoms were collected in a community survey of 7485 persons aged 20-24, 40-44 or 60-64 years. These measures were investigated for factorial invariance across age groups. Data were also collected on a wide range of potential risk factors, including social, physical health and personal factors, with the aim of determining whether these factors might partly or wholly account for age group differences.

RESULTS

The invariance of correlated latent factors representing anxiety and depression was examined across age groups, and a generalized measure of psychological distress was computed. Depression, anxiety and psychological distress showed a decline across age groups for females and a decline from 40-44 to 60-64 years for males. Some of these age differences were accounted for by other risk factors, with the most important being recent crises at work and negative social relationships with family and friends.

CONCLUSION

Psychological distress generally declined across the age range 20-64 years and this was not attributable to measurement bias. Differential exposure to risk factors explained some, but not all, of the age group difference. Therefore other mechanisms that explain the lower level of distress in older age groups remain to be identified.

Memory complaints in a community sample aged 60-64 years: associations with cognitive functioning, psychiatric symptoms, medical conditions, APOE genotype, hippocampus and amygdala volumes, and white-matter hyperintensities

BACKGROUND

Previous research has found that depression is a major cause of memory complaints. However, there is evidence that memory complaints also weakly predict cognitive decline and dementia. The present study examined a range of possible determinants of memory complaints, covering psychiatric and personality factors, medical history, cognitive test performance, and biological risk factors for dementia (APOE genotype, hippocampus and amygdala volumes, and white-matter hyperintensities).

METHOD

A community survey was carried out with 2546 persons aged 60-64 years living in Canberra and Queanbeyan, Australia. Participants were asked about memory problems which interfered with daily life and whether medical help had been sought. A randomly selected subsample of 476 persons was given a brain MRI scan.

RESULTS

Participants with memory complaints were found to have poorer memory test performance, more depression and anxiety symptoms, have higher scores on personality traits involving negative affect, and to have worse physical health. Multivariate analyses showed that measures of cognitive performance did not make a unique contribution to the prediction of memory complaints above that of the other categories of predictors. Those with memory complaints did not differ on any of the biological risk factors for dementia.

CONCLUSION

In a community sample aged 60-64 years, memory complaints were most closely related to psychiatric symptoms, personality characteristics and poor physical health. There was no evidence of brain changes indicating early dementia.

Children of a cohort of depressed patients 25 years later: psychopathology and relationships

BACKGROUND

While many studies have examined cross-sectional or short-term effects of parental depression on children, few have studied such children many years later when they reach adulthood. It was hypothesised that children of patients hospitalised for depression 25 years ago would have more psychological morbidity and relationship difficulties than children of a surgical comparison group.

METHOD

Children (n=94) of depressed patients and a surgical control group (n=31) admitted to a teaching hospital 25 years ago were compared on measures of psychiatric morbidity, personality, marital and family relationships.

RESULTS

Compared with control children, children of depressed patients demonstrated trends for higher rates of non-phobic anxiety and substance disorders, but neither psychological morbidity overall nor affective disorder specifically. Compared with control children, children of depressed patients rated their relationships with fathers who were spouses of female patients more negatively. Having consciously tried to make their own intimate relationships different from that of their parents, children of depressed patients and their partners reported significantly more caring in their relationships compared with control children and their partners.

CONCLUSION

In this study of the effects of parental depression on children 25 years on, adult children of depressed patients demonstrated significant resilience as evidenced by similar rates of overall psychiatric morbidity and quality of intimate relationships to controls. They may be at risk for specific disorders such as anxiety and substance disorder and have problematic relationships with the "well" spouses of depressed patients particularly if the "well" spouse is their father.

Neuropsychological performance and dementia in depressed patients after 25-year follow-up: a controlled study

BACKGROUND

Previous research has yielded conflicting evidence regarding the long-term cognitive outcome of depression. Some studies have found evidence for a higher incidence of subsequent cognitive impairment or dementia, while others have refuted this.

METHOD

Depression, neuropsychological performance, functional ability and clinical variables were assessed in a sample of patients who had been hospitalized for depression 25 years previously.

RESULTS

Data were available on 71 depressed patients (10 of whom were deceased) and 50 surgical controls. No significant differences were found between depressed subjects and controls on any neuropsychological measure. Ten depressed patients but no controls were found to have dementia at follow-up (continuity corrected chi2 = 5.93, P < 0.01). Presence of dementia was predicted by older age at baseline. Vascular dementia was the most common type.

CONCLUSIONS

We conclude that this study did not find evidence that early onset depression is a risk factor for Alzheimer's disease, but that for a small subgroup there appears to be a link with vascular dementia. Several plausible explanations for this link, such as lifestyle factors, require further investigation.

The role of volumetric MRI in understanding mild cognitive impairment and similar classifications

We review nineteen empirical studies of mild cognitive impairment (MCI), age-associated memory impairment (AAMI) and related classifications reporting volumetric data on the hippocampus, entorhinal cortex and amygdala. Studies varied considerably in terms of the selection of participants, sample characteristics, the definitions of regions of interest and normalization techniques. Effect sizes for differences in left hippocampal volume and right hippocampal volumes of AAMI, MCI and pre-clinical dementia groups compared with controls ranged from 0.47 to 1.34. Effect sizes for left and right hippocampal volumes for Alzheimer's disease (AD) versus control were 1.88 and 1.75 respectively. Longitudinal results confirm that initial hippocampal volume is predictive of conversion to AD. Greater standardization in methodology and the development of normative age-referenced databases of regional brain volumes is required.

Two-year decline in vision but not hearing is associated with memory decline in very old adults in a population-based sample

BACKGROUND

Recent cross-sectional research in cognitive aging has demonstrated a robust association between visual acuity, auditory thresholds and cognitive performance in old age. However, the nature of the association is still unclear, particularly with respect to whether sensory and cognitive function are causally related.

OBJECTIVE

This study aimed to determine whether marked declines in performance on screening measures of either visual acuity or auditory thresholds have an effect on cognitive decline over 2 years.

METHODS

The sample from the Australian Longitudinal Study of Ageing (n = 2,087) were assessed in 1992 and 1994 on measures of sensory and cognitive function as part of a larger clinical assessment. A quasi-experimental design involving comparison of extreme groups using repeated measures MANCOVA with age as a covariate was used.

RESULTS

Group performance on measures of hearing, memory, verbal ability and processing speed declined significantly. Decline in visual acuity had a significant effect on memory decline, but not on decline in verbal ability or processing speed. Decline in hearing was not associated with decline in any cognitive domain.

CONCLUSION

The common association between visual acuity, auditory thresholds and cognitive function observed in cross-sectional studies appears to be disassociated in longitudinal studies.

Demographic, health, cognitive, and sensory variables as predictors of mortality in very old adults

Cognitive and sensorimotor predictors of mortality were examined in the Australian Longitudinal Study of Ageing, controlling for demographic and health variables. A stratified random sample of 1,947 males and females aged 70 and older were interviewed, and 1,500 were assessed on measures of health, memory. verbal ability, processing speed, vision, hearing, and grip strength in 1992 and 1994. Analyses of incident rate ratios for mortality over 4- and 6-year periods were conducted using Cox hierarchical regression analyses. Results showed that poor performance on nearly all cognitive variables was associated with mortality, but many of these effects were explained by measures of self-rated health and disease. Significant decline in hearing and cognitive performance also predicted mortality as did incomplete data at Wave 1. Results suggest that poor cognitive performance and cognitive decline in very old adults reflect both biological aging and disease processes.

A reevaluation of the common factor theory of shared variance among age, sensory function, and cognitive function in older adults

The common cause hypothesis of the relationship among age, sensory measures, and cognitive measures in very old adults was reevaluated. Both sensory function and processing speed were evaluated as mediators of the relationship between age and cognitive function. Cognitive function was a latent variable that comprised 3 factors including memory, speed, and verbal ability. The sample was population based and comprised very old adults (n = 894; mean age = 77.7, SD = 5.6 years) from the Australian Longitudinal Study of Ageing. The results showed that there was common variance in the cognitive factor shared by age, speed, vision, and hearing but that specific effects of age on cognition remained. Furthermore, speed did not fully mediate the effect of age or sensory function on cognition. Some age differences in cognitive performance are not explained by the same processes that explain age differences in sensory function and processing speed.

Normative data on neuropsychological tests for very old adults living in retirement villages and hostels

Normative data on neuropsychological tests for very old adults living in retirement villages and hostels are under-represented in the literature. This study reports normative data on the Mini-Mental State Examination, Digit Span Forwards, Digit Span Backwards, the Digit Symbol Substitution Test, the Controlled Oral Word Association Test, the Stroop Neuropsychological Screening Test and the National Adult Reading Test. Age and education showed moderate correlations with neuropsychological test performance. For all tests except the Stroop, differences between residents of retirement villages and hostels were explained by age and education. Men performed better on the NART than women, but this difference was eliminated when education was controlled for statistically.

Interrelationships among biological markers of aging, health, activity, acculturation, and cognitive performance in late adulthood

In this study a structural equation model of predictors of age differences in cognitive performance in late adulthood was developed. Biological markers of aging (vision, hearing, vibration sense, forced expiratory volume, and grip strength) were used as indicators of a latent variable called BioAge. A sample of 180 community-dwelling women aged 60 to 90 years was assessed. Results showed that BioAge explained all of the age-related variance in cognitive test performance. Physical health and physical activity had direct effects on BioAge. Measures of acculturation explained non-age-related variance in cognitive test performance. Some variables used as biomarkers also explained individual differences in measures of crystallized intelligence and perceptual speed. It is concluded that the association between biomarkers and cognition in old age is due to more than a common statistical association with age.

Interrelationships among biological markers of aging, health, activity, acculturation, and cognitive performance in late adulthood

In this study a structural equation model of predictors of age differences in cognitive performance in late adulthood was developed. Biological markers of aging (vision, hearing, vibration sense, forced expiratory volume, and grip strength) were used as indicators of a latent variable called BioAge. A sample of 180 community-dwelling women aged 60 to 90 years was assessed. Results showed that BioAge explained all of the age-related variance in cognitive test performance. Physical health and physical activity had direct effects on BioAge. Measures of acculturation explained non-age-related variance in cognitive test performance. Some variables used as biomarkers also explained individual differences in measures of crystallized intelligence and perceptual speed. It is concluded that the association between biomarkers and cognition in old age is due to more than a common statistical association with age.

Test-retest reliability of a battery of sensory motor and physiological measures of aging

We report test-retest reliabilities for a battery of tests (vision, hearing, vibration sense, proprioception, forced expiratory volume, blood pressure, grip strength, and sway) shown previously to predict functional age. Fifty women aged 60 to 86 were retested on the battery after 3 months. All tests except proprioception and blood pressure had reliabilities between .70 and .94. We conclude that the battery provides reliable measures of sensory, motor, and physiological variables which may be used as markers of biological aging in psychological research.

Strength in the lower limbs, visual contrast sensitivity, and simple reaction time predict cognition in older women

The authors investigated the association between sensorimotor variables indicative of biological aging and cognition. A community sample of 202 women ages 60-86 was assessed on 5 measures of lower limb strength, visual contrast sensitivity (VisCS), and reaction time (RT). Hierarchical multiple regression revealed that the sensorimotor variables explained age-related variance in measures of reasoning and total variance in measures of reasoning after education, health, mood, and physical activity were controlled for. It is concluded that in addition to better known predictors of cognitive aging, such as RT and VisCS, lower limb strength is an important predictor of performance on cognitive tests.

Measuring human functional age: a review of empirical findings

A review of empirical functional age studies published in English was conducted. Types of biomarkers used in functional age studies included sensorimotor, cognitive, psychosocial, behavioral, anthropometric, biomedical, physiological, and dental variables. Previous criticisms of the validity and utility of functional age research were evaluated with reference to empirical studies. While some of these criticisms remain valid, areas of research currently using established biomarkers to predict functional outcomes were identified, including driving, falls, and cognitive functioning. It was concluded that the success of functional age research is dependent on the relevance of biomarkers to specific functional outcomes.

Psychoactive medication use, sensori-motor function and falls in older women

1. A 1 year prospective study was undertaken to identify possible mediating physiological mechanisms for the association between psychoactive medication use and falls in 414 women aged 65 to 99 years (mean age 73.7 years, s.d. = 6.3) who were randomly selected from the community. 2. Women taking certain psychoactive medications showed impaired performance in a number of sensori-motor measures, including tactile sensitivity, lower limb muscle strength, reaction time and balance control compared with women not taking these medications. Those using psychoactive medications were also comparatively inactive--taking part in only 1.1 h of planned exercise per week compared with 2.6 h for non-users (F = 12.44, df = 1,412, P < 0.01). 3. Multiple logistic regression analysis revealed that use of long-acting benzodiazepines (OR = 7.03, 95% CI = 2.12-23.28) and antidepressants (OR = 2.84, 95% CI = 1.00-8.02) was significantly associated with multiple falls, whilst adjusting for age, other drug category use, frequency of alcohol use, and number of medical conditions. Use of any two psychoactive medications was also significantly associated with falling frequency (Chi-square = 13.91, df = 1, P < 0.01). 4. Path analysis revealed a significant direct association (P < 0.001) between psychoactive medication use and falls, and a significant indirect association mediated via reduced physiological functioning (P < 0.001). Postural hypotension was not significantly associated with falls (RR = 1.37, 95% CI = 0.84-2.22). 5. The findings suggest that psychoactive medication use may predispose older people to falling by impairing important sensori-motor systems that contribute to postural stability.

Physiological factors associated with falls in older community-dwelling women

OBJECTIVE

To determine the prevalence of impaired vision, peripheral sensation, lower limb muscle strength, reaction time, and balance in a large community-dwelling population of women aged 65 years and over, and to determine whether impaired performances in these tests are associated with falls.

DESIGN

One-year prospective study.

SETTING

Conducted as part of the Randwick Falls and Fractures Study, in Sydney, Australia.

PARTICIPANTS

Four hundred fourteen women aged 65 to 99 years (mean age 73.7 years, SD = 6.3) were randomly selected from the community; 341 of these women were included in the 1-year prospective study.

MAIN RESULTS

The prevalence of impairment in all tests increased with age. In the year following assessment, 207 subjects (60.7%) experienced no falls, 63 subjects (18.5%) fell one time only, and 71 subjects (20.8%) fell on two or more occasions. After controlling for age, multiple falling was associated with low contrast visual acuity and contrast sensitivity, poor vibration sense and proprioception, reduced lower limb strength, slow reaction time, and impaired balance, as indicated by four sway tests and two clinical stability measures. Discriminant function analysis identified visual contrast sensitivity, proprioception in the lower limbs, quadriceps strength, reaction time, and sway on a compliant (foam rubber) surface with the eyes open as the variables that significantly discriminated between subjects who experienced multiple falls and subjects who experienced no falls or one fall only (Wilks' lambda = 0.73 (P < 0.001), canonical correlation = 0.52). This procedure correctly classified 75% of subjects into multiple faller or nonmultiple faller groups.

CONCLUSIONS

These findings support previous results conducted in retirement village and institutional setting and indicate that the test procedure aids in the identification of older community-dwelling women at risk of falls.

An epidemiological study of falls in older community-dwelling women: the Randwick falls and fractures study

Seven hundred and four women aged between 65 and 99 years (mean age 74.6 years), who were randomly selected from the community, took part in a study to determine whether health and lifestyle factors were associated with falls. In the 12 months before the survey, 66.1 per cent of the subjects experienced no falls, 19.7 per cent fell once and 14.2 per cent fell on two or more occasions. The proportion of women who fell outside the home decreased with age, with a corresponding increase in the proportion who fell inside the home on a level surface. The most common causes of falls reported were trips, slips and loss of balance. Some (27 per cent) suffered injuries as a result of a fall, and the proportion suffering injuries increased with age. Those who rated their health and balance as impaired, those with a limitation in activities of daily living, those receiving community services, those taking psychoactive drugs, and those taking four or more drugs had significantly more falls. On the other hand, those taking part in planned exercise and those active for seven or more hours per week had fewer falls. Smoking and alcohol consumption were not significantly associated with falls. Stepwise logistic regression analysis revealed poor vision, inactivity and subjective fall risk as variables that were independently and significantly associated with falling. These findings highlight possible intervention strategies for reducing falls risk in older people.