Obioha C. Ukoumunne

Mediterranean Diet, Cognitive Function, and Dementia A Systematic Review

Background: Adherence to a Mediterranean diet has been associated with lower risk of various age-related diseases including dementia. Although narrative reviews have been published, no systematic review has synthesized studies on the association between Mediterranean diet adherence and cognitive function or dementia. Methods: We conducted a systematic review of 11 electronic databases (including Medline) of published articles up to January 2012. Reference lists, selected journal contents, and relevant websites were also searched. Study selection, data extraction, and quality assessment were performed independently by two reviewers using predefined criteria. Studies were included if they examined the association between a Mediterranean diet adherence score and cognitive function or dementia. Results: Twelve eligible papers (11 observational studies and one randomized controlled trial) were identified, describing seven unique cohorts. Despite methodological heterogeneity and limited statistical power in some studies, there was a reasonably consistent pattern of associations. Higher adherence to Mediterranean diet was associated with better cognitive function, lower rates of cognitive decline, and reduced risk of Alzheimer disease in nine out of 12 studies, whereas results for mild cognitive impairment were inconsistent. Conclusions: Published studies suggest that greater adherence to Mediterranean diet is associated with slower cognitive decline and lower risk of developing Alzheimer disease. Further studies would be useful to clarify the association with mild cognitive impairment and vascular dementia. Long-term randomized controlled trials promoting a Mediterranean diet may help establish whether improved adherence helps to prevent or delay the onset of Alzheimer disease and dementia.

Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis

BACKGROUND Differences in systolic blood pressure (SBP) of 10 mm Hg or more or 15 mm Hg or more between arms have been associated with peripheral vascular disease and attributed to subclavian stenosis. We investigated whether an association exists between this difference and central or peripheral vascular disease, and mortality. METHODS We searched Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane, and Medline In Process databases for studies published before July, 2011, showing differences in SBP between arms, with data for subclavian stenosis, peripheral vascular disease, cerebrovascular disease, cardiovascular disease, or survival. We used random effects meta-analysis to combine estimates of the association between differences in SBP between arms and each outcome. FINDINGS We identified 28 eligible studies for review, 20 of which were included in our meta-analyses. In five invasive studies using angiography, mean difference in SBP between arms was 36·9 mm Hg (95% CI 35·4-38·4) for proven subclavian stenosis (>50% occlusion), and a difference of 10 mm Hg or more was strongly associated with subclavian stenosis (risk ratio [RR] 8·8, 95% CI 3·6-21·2). In non-invasive studies, pooled findings showed that a difference of 15 mm Hg or more was associated with peripheral vascular disease (nine cohorts; RR 2·5, 95% CI 1·6-3·8; sensitivity 15%, 9-23; specificity 96%, 94-98); pre-existing cerebrovascular disease (five cohorts; RR 1·6, 1·1-2·4; sensitivity 8%, 2-26; specificity 93%, 86-97); and increased cardiovascular mortality (four cohorts; hazard ratio [HR] 1·7, 95% CI 1·1-2·5) and all-cause mortality (HR 1·6, 1·1-2·3). A difference of 10 mm Hg or higher was associated with peripheral vascular disease (five studies; RR 2·4, 1·5-3·9; sensitivity 32%, 23-41; specificity 91%, 86-94). INTERPRETATION A difference in SBP of 10 mm Hg or more, or of 15 mm Hg or more, between arms might help to identify patients who need further vascular assessment. A difference of 15 mm Hg or more could be a useful indicator of risk of vascular disease and death. FUNDING Royal College of General Practitioners, South West GP Trust, and Peninsula Collaboration for Leadership in Applied Health Research and Care.

Lessons for cluster randomized trials in the twenty-first century: a systematic review of trials in primary care

Background Evidence suggests that cluster randomized trials are often poorly designed and analysed. There is little recent research on the methodologic quality of cluster randomized trials and none focuses on primary health care where these trials are increasingly common. Methods We conducted a systematic review of recent cluster randomized trials in primary health care, searching the Cochrane Controlled Trials Register. We also searched for unpublished trials in conference proceedings, and the UK National Research Register. We assess methodologic quality using a checklist, articulate problems facing investigators conducting these trials, and examine the extent to which carrying out a cluster randomized trial (as opposed to an individually randomized trial) in primary care may reduce power. Results We found 367 trial reports. Many trials were reported more than once. We characterize 152 independent cluster randomized trials in primary health care published between 1997 and 2000, and brie‘y describe 47 trials unpublished at December 2000. The quality of design and analysis was variable. Of published trials reporting sample size calculations 20% accounted for clustering in these calculations, 59% of published trials accounted for clustering in analyses. Unpublished trials were more recent and of higher quality. Reporting quality was better in journals reporting more cluster randomized trials. Many trial investigators reported problems with adherence to protocol, recruitment and type of intervention. Conclusions Methodologic quality of cluster randomized trials in primary health care is variable and reporting needs improvement. The use of cluster randomization should be indicated in the title or abstract so these kinds of trials are easier to identify. Communicating appropriate methodology to health care researchers continues to be a challenge. Cluster randomized trials should always be piloted and information from pilots and unsuccessful trials shared more widely. Introduction Cluster randomized trials, in which groups or clusters of individuals rather than the individuals themselves are randomized to intervention and control groups, are increasingly popular and particularly common in primary health care. This is because much current primary health service research centres on interventions to improve practice [1], often involving changes in patient behaviour, health professional behaviour, or organization. Controlled trials randomizing individual

Outcomes and costs of primary care surveillance and intervention for overweight or obese children: the LEAP 2 randomised controlled trial

Objective To determine whether ascertainment of childhood obesity by surveillance followed by structured secondary prevention in primary care improved outcomes in overweight or mildly obese children. Design Randomised controlled trial nested within a baseline cross sectional survey of body mass index (BMI). Randomisation and outcomes measurement, but not participants, were blinded to group assignment. Setting 45 family practices (66 general practitioners) in Melbourne, Australia. Participants 3958 children visiting their general practitioner in May 2005-July 2006 were surveyed for BMI. Of these, 258 children aged 5 years 0 months up to their 10th birthday who were overweight or obese by International Obesity Taskforce criteria were randomised to intervention (n=139) or control (n=119) groups. Children who were very obese (UK BMI z score ≥3.0) were excluded. Intervention Four standard consultations over 12 weeks targeting change in nutrition, physical activity, and sedentary behaviour, supported by purpose designed family materials. Main outcomes measures Primary measure was BMI at 6 and 12 months after randomisation. Secondary measures were mean activity count/min by 7-day accelerometry, nutrition score from 4-day abbreviated food frequency diary, and child health related quality of life. Differences were adjusted for socioeconomic status, age, sex, and baseline BMI. Results Of 781 eligible children, 258 (33%) entered the trial; attrition was 3.1% at 6 months and 6.2% at 12 months. Adjusted mean differences (intervention − control) at 6 and 12 months were, for BMI, −0.12 (95% CI −0.40 to 0.15, P=0.4) and −0.11 (−0.45 to 0.22, P=0.5); for physical activity in counts/min, 24 (−4 to 52, P=0.09) and 11 (−26 to 49, P=0.6); and, for nutrition score, 0.2 (−0.03 to 0.4, P=0.1) and 0.1 (−0.1 to 0.4, P=0.2). There was no evidence of harm to the child. Costs to the healthcare system were significantly higher in the intervention arm. Conclusions Primary care screening followed by brief counselling did not improve BMI, physical activity, or nutrition in overweight or mildly obese 5-10 year olds, and it would be very costly if universally implemented. These findings are at odds with national policies in countries including the US, UK, and Australia. Trial registration ISRCTN 52511065 (www.isrctn.org)

Predicting Language Outcomes at 4 Years of Age: Findings From Early Language in Victoria Study

OBJECTIVE: To quantify the contributions of child, family, and environmental predictors to language ability at 4 years. METHODS: A longitudinal study was performed with a sample of 1910 infants recruited at 8 months in Melbourne, Australia. Predictors were child gender, prematurity, birth weight and order, multiple birth, socioeconomic status, maternal mental health, vocabulary, education, and age at childs birth, non–English-speaking background, and family history of speech/language difficulties. Outcomes were Clinical Evaluation of Language Fundamentals-Preschool, language scores, low language status (scores >1.25 SDs below the mean), and specific language impairment (SLI) (scores >1.25 SDs below the mean for children with normal nonverbal performance). RESULTS: A total of 1596 children provided outcome data. Twelve baseline predictors explained 18.9% and 20.9% of the variation in receptive and expressive scores, respectively, increasing to 23.6% and 30.4% with the addition of late talking status at age 2. A total of 20.6% of children (324 of 1573 children) met the criteria for low language status and 17.2% (251 of 1462 children) for SLI. Family history of speech/language problems and low maternal education levels and socioeconomic status predicted adverse language outcomes. The combined predictors discriminated only moderately between children with and without low language levels or SLIs (area under the curve: 0.72–0.76); this improved with the addition of late talking status (area under the curve: 0.78–0.84). CONCLUSIONS: Measures of social disadvantage helped explain more variation in outcomes at 4 years than at 2 years, but ability to predict low language status and SLI status remained limited.

Randomized controlled trial of brief cognitive behaviour therapy versus treatment as usual in recurrent deliberate self-harm: the POPMACT study

BACKGROUND We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined.

Adverse associations of sleep problems in Australian preschoolers: national population study

OBJECTIVE. In contrast to school-aged children, the impact of sleep problems in preschool-aged children is not well documented. We aimed to determine relationships between preschool-aged child sleep problems and child behavior; health-related quality of life; verbal, preliteracy, and early numeracy skills; diagnosis of attention-deficit/hyperactivity disorder; and injury. PARTICIPANTS AND METHODS. Participants included families (n = 4983) participating in the first wave of the Longitudinal Study of Australian Children, a nationally representative study of Australian children aged 4 to 5 years surveyed from March to November 2004. Measures consisted of a primary caregivers report of whether their child had a sleep problem (none versus mild versus moderate/severe); specific sleep patterns occurring ≥4 nights per week; health-related quality of life (by using the Pediatric Quality of Life Inventory 4.0); behavior (by using the Strengths and Difficulties Questionnaire) and parent-reported diagnosis of attention-deficit/hyperactivity disorder; and injury requiring medical attention in the past 12 months. Tests of receptive vocabulary and preliteracy/numeracy skills (by using the Who Am I? developmental assessment and the adapted Peabody Picture Vocabulary Test, 3rd Edition) were directly administered to each child. RESULTS. Sleep problems were common, and compared with children without sleep problems, children with sleep problems had poorer child health-related quality of life, more behavior problems, and higher rates of attention-deficit/hyperactivity disorder. Difficulty going to sleep and morning tiredness had greater adverse associations than snoring or night waking. CONCLUSIONS. Given that sleep problems are very common, the adverse outcomes shown here could affect the transition to school for a very large number of preschoolers.

Predicting Language at 2 Years of Age: A Prospective Community Study

OBJECTIVE. This article responds to evidence gaps regarding language impairment identified by the US Preventive Services Task Force in 2006. We examine the contributions of putative child, family, and environmental risk factors to language outcomes at 24 months of age. METHODS. A community-ascertained sample of 1720 infants who were recruited at 8 months of age were followed at ages 12 and 24 months in a prospective, longitudinal study in metropolitan Melbourne, Australia. Outcomes at 24 months were parent-reported infant communication (Communication and Symbolic Behavior Scales and MacArthur-Bates Communicative Development Inventories vocabulary production score). Putative risk factors were gender, preterm birth, birth weight, multiple birth, birth order, socioeconomic status, maternal mental health, maternal vocabulary and education, maternal age at birth of child, non–English-speaking background, and family history of speech-language difficulties. Linear regression models were fitted to total standardized Communication and Symbolic Behavior Scales and Communicative Development Inventories vocabulary production scores; a logistic regression model was fitted to late-talking status at 24 months. RESULTS. The regression models accounted for 4.3% and 7.0% of the variation in the 24-month Communication and Symbolic Behavior Scales and Communicative Development Inventories scores, respectively. Male gender and family history were strongly associated with poorer outcomes on both instruments. Lower Communication and Symbolic Behavior Scales scores were also associated with lower maternal vocabulary and older maternal age. Lower vocabulary production scores were associated with birth order and non–English-speaking background. When the 12-month Communication and Symbolic Behavior Scales Total score was added as a covariate in the linear regression of 24-month Communication and Symbolic Behavior Scales Total score, it was by far the strongest predictor. CONCLUSIONS. These early risk factors explained no more than 7% of the variation in language at 24 months. They seem unlikely to be helpful in screening for early language delay.

A Parent-Focused Intervention to Reduce Infant Obesity Risk Behaviors: A Randomized Trial

OBJECTIVE: To assess the effectiveness of a parent-focused intervention on infants’ obesity-risk behaviors and BMI. METHODS: This cluster randomized controlled trial recruited 542 parents and their infants (mean age 3.8 months at baseline) from 62 first-time parent groups. Parents were offered six 2-hour dietitian-delivered sessions over 15 months focusing on parental knowledge, skills, and social support around infant feeding, diet, physical activity, and television viewing. Control group parents received 6 newsletters on nonobesity-focused themes; all parents received usual care from child health nurses. The primary outcomes of interest were child diet (3 × 24-hour diet recalls), child physical activity (accelerometry), and child TV viewing (parent report). Secondary outcomes included BMI z-scores (measured). Data were collected when children were 4, 9, and 20 months of age. RESULTS: Unadjusted analyses showed that, compared with controls, intervention group children consumed fewer grams of noncore drinks (mean difference = –4.45; 95% confidence interval [CI]: –7.92 to –0.99; P = .01) and were less likely to consume any noncore drinks (odds ratio = 0.48; 95% CI: 0.24 to 0.95; P = .034) midintervention (mean age 9 months). At intervention conclusion (mean age 19.8 months), intervention group children consumed fewer grams of sweet snacks (mean difference = –3.69; 95% CI: –6.41 to –0.96; P = .008) and viewed fewer daily minutes of television (mean difference = –15.97: 95% CI: –25.97 to –5.96; P = .002). There was little statistical evidence of differences in fruit, vegetable, savory snack, or water consumption or in BMI z-scores or physical activity. CONCLUSIONS: This intervention resulted in reductions in sweet snack consumption and television viewing in 20-month-old children.

Effectiveness of the Mindfulness in Schools Programme: non-randomised controlled feasibility study

BACKGROUND Mindfulness-based approaches for adults are effective at enhancing mental health, but few controlled trials have evaluated their effectiveness among young people. AIMS To assess the acceptability and efficacy of a schools-based universal mindfulness intervention to enhance mental health and well-being. METHOD A total of 522 young people aged 12-16 in 12 secondary schools either participated in the Mindfulness in Schools Programme (intervention) or took part in the usual school curriculum (control). RESULTS Rates of acceptability were high. Relative to the controls, and after adjusting for baseline imbalances, children who participated in the intervention reported fewer depressive symptoms post-treatment (P = 0.004) and at follow-up (P = 0.005) and lower stress (P = 0.05) and greater well-being (P = 0.05) at follow-up. The degree to which students in the intervention group practised the mindfulness skills was associated with better well-being (P<0.001) and less stress (P = 0.03) at 3-month follow-up. CONCLUSIONS The findings provide promising evidence of the programmes acceptability and efficacy.