Are Population-Level Approaches to Dementia Risk Reduction Under-Researched? A Rapid Review of the Dementia Prevention Literature.

Dementia is forecast to become increasingly prevalent, particularly in low- and middle-income countries, and is associated with high human and economic costs. Primary prevention of dementia -preventing risk factors leading to disease development - is an emerging global public health priority. Primary prevention can be achieved in two ways: individual-level or population-level. In this rapid review, we quantify the proportion of contributing interventional evidence to the dementia primary prevention literature that is concerned with either approach. We searched Medline, the National Institute for Health and Care Excellence, Cochrane, the World Health Organization, and Google to identify systematic reviews that described primary prevention interventions for dementia. We used search terms related to dementia risk reduction, intervention/policy, and review. We analysed reference lists of included dementia prevention reviews to identify contributing primary prevention evidence, and categorised these as either individual-level or population-level. Additionally, we examined search strategies to investigate the likelihood of reviews identifying available population-level interventions. We included twelve of the 527 articles retrieved. Population-level evidence was summarised by only two reviews. In these two reviews, <2.5% of the interventions described where population-level interventions. Most search strategies were weighted towards identifying individual-level evidence. Existing systematic reviews of dementia primary prevention interventions include almost no population-level evidence. Correction of this imbalance is needed to ensure that dementia prevention policies can achieve meaningful reductions in the prevalence of, and inequalities in, dementia.

What is a population-level approach to prevention, and how could we apply it to dementia risk reduction?

The World Health Organisation's 2022 'blueprint for dementia research' highlights the need for more research into population-level risk reduction. However, definitions of population-level prevention vary, and application to dementia is challenging because of its multi-factorial aetiology and a maturing prevention evidence base. This paper compares and contrasts key concepts of 'population-level prevention' from the literature, explores related theoretical models and policy frameworks, and applies this to dementia risk reduction. We reach a proposed definition of population-level risk reduction of dementia, which focusses on the need to change societal conditions such that the population is less likely to develop modifiable risk factors known to be associated with dementia, without the need for high-agency behaviour change by individuals. This definition, alongside identified policy frameworks, can inform synthesis of existing evidence and help to co-ordinate the generation of new evidence.

Variation in incidence and notification of Campylobacter and Salmonella by general practice in the Thames Valley area.

OBJECTIVES: To test whether there is unexplained variation in a) incidence of diagnosed bacterial food poisoning; and b) notification of bacterial food poisoning between general practices. STUDY DESIGN: Observational study using routine surveillance data collected between 1 January 2008 and 31 December 2009. METHODS: Poisson regression, and the pseudo-R(2) statistic, was used to test for the unexplained (i.e. after adjustment for measured confounders) variation in incidence between practices. A generalized linear model, and the pseudo-R(2) statistic, was used to test for variation in notifications between practices. Both models were adjusted for demographic factors and organisational factors (Primary Care Trust and Quality and Outcomes Framework score). RESULTS: A total of 5766 incident cases (811 Salmonella and 4955 Campylobacter) were included. The adjusted incidence of Salmonella and Campylobacter was 128.3 cases per 100,000 persons per year. The adjusted incidence by general practice ranged from 9.8 to 281 per 100,000 (IQR: 90.2-151) persons per year. The median practice notification rate for Salmonella was 25% (range: 0%-100%), and 14.3% (range: 0%-87.5%) for Campylobacter. The Poisson regression model had a pseudo-R(2) of 0.080 for the total number of Salmonella and Campylobacter cases, after adjustment for Primary Care Trust and practice deprivation, suggesting substantial variation. The Generalized Linear regression model (predicting notification by general practice) had a pseudo-R(2) of 0.040 for Salmonella and Campylobacter, after adjustment for Primary Care Trust and practice deprivation, suggesting substantial unexplained variation. CONCLUSION: Substantial variation in the diagnosed incidence and notification of Salmonella and Campylobacter by general practice in the Thames Valley area exists. Practice-level factors are likely to account for some of the difference in testing and under-notification. This is important for interpreting data from surveillance systems. Further research is needed to inform interventions designed to increase notifications or improve testing.

Knowledge, attitudes and beliefs of health care workers towards influenza vaccination.

BACKGROUND: Influenza vaccination is routinely offered to health care workers in the U.K. to prevent nosocomial spread to patients and illness among health care workers. Despite its importance uptake has been low in the U.K. AIMS: To describe the knowledge, attitudes and behaviour of health care workers towards influenza vaccination offered as part of occupational health and to understand their relative importance in promoting uptake of influenza vaccine. We also sought to make comparisons with other vaccines more readily accepted as part of occupational health. METHODS: An online survey was distributed by e-mail to health care workers in the South Central Strategic Health Authority. The questionnaire included the following: demographic characteristics; vaccination status; and knowledge, attitudes and behaviour towards influenza, MMR and hepatitis B vaccination. We used logistic regression to identify the independent predictors of receipt of influenza vaccine. RESULTS: The survey was completed by 998 health care workers representing just over 1% of health care workers in the region. Of those, 69% thought that overall benefits of influenza vaccination were greater than the risks and inconvenience (versus 92% for hepatitis B and 86% for MMR). The following predicted receipt of influenza vaccine: belief that influenza poses a risk to one's own health (OR 3.74; 95% CI 2.45-5.71); belief that influenza vaccine is harmful (OR 0.25; 95% CI 0.16-0.37); and belief that influenza vaccine will protect patients (OR 2.96; 95% CI 1.89-4.62). CONCLUSIONS: Staff knowledge, attitudes and beliefs concerning influenza and its vaccine are an important predictor of uptake and should be a target for campaigns to promote uptake.

Influenza A(H1N1)pdm09 in England, 2009 to 2011: a greater burden of severe illness in the year after the pandemic than in the pandemic year.

Influenza pandemics are often perceived as single-year events, but the burden of previous influenza pandemics has in reality been spread over a number of years. The aim of this paper is to compare the burden of influenza in the pandemic year 2009/10 with that in the year immediately after (2010/11) in England. We compared four measures of disease. There was a greater burden of severe illness in 2010/11 compared with 2009/10: more deaths (474 vs 361), more critical care admissions (2,200 vs 1,700), and more hospital admissions (8,797 vs 7,879). In contrast, there were fewer general practice consultations in 2010/11 compared with 2009/10 (370,000 vs 580,000). There was also much less public interest in influenza, as assessed by number of Google searches. This is a worrying finding, as by the time of the second influenza season, much had been learnt about the potential impact of the influenza A(H1N1)pdm09 virus and an effective vaccine developed. We suggest that a widespread assumption of 'mildness' led to insufficient ongoing action to prevent influenza and hence to avoidable influenza-related deaths. This offers a lesson to all countries, both for future influenza seasons and for pandemic preparedness planning.

Mortality due to pandemic (H1N1) 2009 influenza in England: a comparison of the first and second waves.

Deaths in England attributable to pandemic (H1N1) 2009 deaths were investigated through a mandatory reporting system. The pandemic came in two waves. The second caused greater population mortality than the first (5·4 vs. 1·6 deaths per million, P<0·001). Mortality was particularly high in those with chronic neurological disease, chronic heart disease and immune suppression (450, 100, and 94 deaths per million, respectively); significantly higher than in those with chronic respiratory disease (39 per million) and those with no risk factors (2·4 per million). Greater mortality in the second wave has been observed in all previous influenza pandemics. This time, the explanation appears to be behavioural. This emphasizes the importance of maintaining public and clinical awareness of risks associated with pandemic influenza beyond the initial high-profile period.

Hospitalization in two waves of pandemic influenza A(H1N1) in England.

Uncertainties exist regarding the population risks of hospitalization due to pandemic influenza A(H1N1). Understanding these risks is important for patients, clinicians and policy makers. This study aimed to clarify these uncertainties. A national surveillance system was established for patients hospitalized with laboratory-confirmed pandemic influenza A(H1N1) in England. Information was captured on demographics, pre-existing conditions, treatment and outcomes. The relative risks of hospitalization associated with pre-existing conditions were estimated by combining the captured data with population prevalence estimates. A total of 2416 hospitalizations were reported up to 6 January 2010. Within the population, 4·7 people/100,000 were hospitalized with pandemic influenza A(H1N1). The estimated hospitalization rate of cases showed a U-shaped distribution with age. Chronic kidney disease, chronic neurological disease, chronic respiratory disease and immunosuppression were each associated with a 10- to 20-fold increased risk of hospitalization. Patients who received antiviral medication within 48 h of symptom onset were less likely to be admitted to critical care than those who received them after this time (adjusted odds ratio 0·64, 95% confidence interval 0·44-0·94, P=0·024). In England the risk of hospitalization with pandemic influenza A(H1N1) has been concentrated in the young and those with pre-existing conditions. By quantifying these risks, this study will prove useful in planning for the next winter in the northern and southern hemispheres, and for future pandemics.

Safety of benzyl benzoate lotion and permethrin in pregnancy: a retrospective matched cohort study.

OBJECTIVE: To assess the safety of benzyl benzoate lotion (BBL) and permethrin, topical treatments for scabies, during pregnancy. DESIGN: A retrospective controlled cohort study. POPULATION: Refugee and migrant women attending antenatal clinics (ANC) on the Thai-Burmese border between August 1993 and April 2006. METHODS: Women treated with either BBL (25%) or permethrin (4%) were identified from a manual search of antenatal records. Each case of scabies was matched with four scabies-free controls for gravidity, age, smoking status, malaria, period of treatment and gestational age at treatment. Conditional Poisson regression was used to estimate risk ratios for outcomes of pregnancy (proportion of abortions, congenital abnormalities, neonatal deaths, stillbirths and premature babies), mean birthweight and estimated median gestational age, for scabies and scabies-free women, independently for BBL and permethrin. RESULTS: There were no statistically significant differences in pregnancy outcomes between women who were treated with either BBL (n = 444) compared with their matched controls (n = 1,776) or permethrin (n = 196) treated women and their matched controls (n = 784). Overall, only 10.9% (n = 66) of treatments were in the first trimester. Retreatment rates were higher with BBL 16.4%, than permethrin 9.7%, P = 0.038. Scabies was more common during cooler periods. CONCLUSION: We found no evidence of adverse effects on pregnancy outcome due to topical 25% BBL or 4% permethrin.

Should doctors talk to relatives without a competent patient's consent?

A view from a student: ethical teaching, based on ethical guidelines, is at odds with clinical practice. Is this poor practice, or is the ethical guidance too simple?