Dementia incidence trend over 1992-2014 in the Netherlands: analysis of primary care data

$\textbf{Background:}$ Recent reports have suggested declining age-specific incidence rates of dementia in high-income countries over time. Improved education and cardiovascular health in early age have been suggested to bring about this effect. The aim of this study was to estimate the age- specific dementia-incidence trend in primary care records from a large population in the Netherlands. $\textbf{Methods and findings:}$ A dynamic cohort representative of the Dutch population was composed using primary care records from general practice registration networks (GPRN) across the country. Data regarding dementia incidence were obtained using general practitioner-recorded diagnosis of dementia within the electronic health records. Age-specific dementia incidence rates were calculated for all persons aged 60 years and over; negative binomial regression analysis was used to estimate the time trend. Nine out of eleven GPRNs provided data on more than 800,000 older people between 1992 and 2014, corresponding to over 4 million person- years and 23,186 incident dementia cases. The annual growth in dementia incidence rate was estimated to be 2.1% (95%CI 0.5 to 3.8%), and incidence rates were 1.08 (95%CI 1.04 to 1.13) times higher for women compared to men. There was no significant overall change since the start of a national dementia program in 2003. Despite their relatively low numbers of person years, the highest age groups contributed most to the increasing trend. Increased awareness of dementia by patients and doctors in more recent years may have influenced dementia diagnosis in GPs’ electronic health records, and needs to be taken into account when interpreting the data. $\textbf{Conclusions:}$ Within the clinical records of a large, representative sample of the Dutch population, we found no evidence for a declining incidence trend of dementia in the Netherlands. This could indicate true stability in incidence rates, or a balance between increased detection and a true reduction. Irrespective of the exact rates and mechanisms underlying these findings, they illustrate that the burden of work for physicians and nurses in general practice associated with newly diagnosed dementia has not been subject to substantial change in the past two decades. Hence, with the ageing of Western societies, we still need to anticipate on a dramatic absolute increase of dementia occurrence over the years to come

Effectiveness of a web-based health risk assessment with individually-tailored feedback on lifestyle behaviour: study protocol

<p>Abstract</p> <p>Background</p> <p>Physical inactivity, unhealthy dietary habits, smoking and high alcohol consumption are recognized risk factors for cardiovascular disease and cancer. Web-based health risk assessments with tailored feedback seem promising in promoting a healthy lifestyle. This study evaluates the effectiveness of a web-based health risk assessment with individually-tailored feedback on lifestyle behaviour, conducted in a worksite setting.</p> <p>Methods/Design</p> <p>The web-based health risk assessment starts with a questionnaire covering socio-demographic variables, family and personal medical history, lifestyle behaviour and psychological variables. Prognostic models are used to estimate individual cardiovascular risks. In case of high risk further biometric and laboratory evaluation is advised. All participants receive individually-tailored feedback on their responses to the health risk assessment questionnaire. The study uses a quasi-experimental design with a waiting list control group. Data are collected at baseline (T0) and after six months (T1). Within each company, clusters of employees are allocated to either the intervention or the control group. Primary outcome is lifestyle behaviour, expressed as the sum of five indicators namely physical activity, nutrition, smoking behaviour, alcohol consumption, and symptoms of burnout. Multilevel regression analysis will be used to answer the main research question and to correct for clustering effects. Baseline differences between the intervention and control group in the distribution of characteristics with a potential effect on lifestyle change will be taken into account in further analyses using propensity scores.</p> <p>Discussion</p> <p>This study will increase insight into the effectiveness of health risk assessments with tailored feedback and into conditions that may modify the effectiveness. This information can be used to design effective interventions for lifestyle behaviour change among employees.</p> <p>Trial registration</p> <p>Dutch Trial Register <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=NTR8148">NTR8148</a>.</p