The changing pattern of statin use in people with dementia: A population-based study

Risks and Benefits of Clinical Diagnosis Around the Time of Dementia Onset

Diagnostic delay in dementia is common in the U.S. Drivers of diagnostic delay are poorly understood, but appear related to misconceptions about dementia, stigma, concerns about autonomy, the nature of the diagnostic process, and provider-related factors. There is little quantitative evidence underlying cited risks and benefits of receiving a diagnosis around the time of dementia onset, including impacts on physical health, impacts on mental health, care partner interactions, costs of care, increased time for care planning, or earlier access to treatment. While various groups continue to push for reductions in diagnostic delay, realization of benefits and mitigation of harms will require new research on potential benefits and harms. Workforce and resource constraints, coupled with the expected growth in the number of persons living with dementia, may be a barrier to realization of potential benefits and mitigation of identified harms, which will require adequate access to providers, services, and supports.

Validity of three risk prediction models for dementia or cognitive impairment in Australia

BACKGROUND

no studies have compared the predictive validity of different dementia risk prediction models in Australia.

OBJECTIVES

(i) to investigate the predictive validity of the Australian National University-Alzheimer's Disease Risk Index (ANU-ADRI), LIfestyle for BRAin Health (LIBRA) Index and cardiovascular risk factors, ageing and dementia study (CAIDE) models for predicting probable dementia/cognitive impairment in an Australian cohort. (ii) To develop and assess the predictive validity of a new hybrid model combining variables from the three models.

METHODS

the Hunter Community Study (HCS) included 3,306 adults aged 55-85 years with a median follow-up of 7.1 years. Probable dementia/cognitive impairment was defined using Admitted Patient Data Collection, dispensing of cholinesterase inhibitors or memantine, or a cognitive test. Model validity was assessed by calibration and discrimination. A hybrid model was developed using deep neural network analysis, a machine learning method.

RESULTS

120 (3.6%) participants developed probable dementia/cognitive impairment. Mean calibration by ANU-ADRI, LIBRA, CAIDE and the hybrid model was 19, 0.5, 4.7 and 3.4%, respectively. The discrimination of the models was 0.65 (95% CI 0.60-0.70), 0.65 (95% CI 0.60-0.71), 0.54 (95% CI 0.49-0.58) and 0.80 (95% CI 0.78-0.83), respectively.

CONCLUSION

ANU-ADRI and LIBRA were better dementia prediction tools than CAIDE for identification of high-risk individuals in this cohort. ANU-ADRI overestimated and LIBRA underestimated the risk. The new hybrid model had a higher predictive performance than the other models but it needs to be validated independently in longitudinal studies.

Statins and cognition: Modifying factors and possible underlying mechanisms

Statins are a class of widely prescribed drugs used to reduce low-density lipoprotein cholesterol (LDL-C) and important to prevent cardiovascular diseases (CVD). Most statin users are older adults with CVD, who are also at high risk of cognitive decline. It has been suggested that statins can alter cognitive performance, although their positive or negative effects are still debated. With more than 200 million people on statin therapy worldwide, it is crucial to understand the reasons behind discrepancies in the results of these studies. Here, we review the effects of statins on cognitive function and their association with different etiologies of dementia, and particularly, Alzheimer's disease (AD). First, we summarized the main individual and statin-related factors that could modify the cognitive effects of statins. Second, we proposed the underlying mechanisms for the protective and adverse effects of statins on cognitive performance. Finally, we discussed potential causes of discrepancies between studies and suggested approaches to improve future studies assessing the impact of statins on dementia risk and cognitive function.

Statin discontinuation in persons with and without Alzheimer's disease

Background

Although statin use is reported to decrease after dementia diagnosis, time to statin discontinuation and factors associated with discontinuation have not been studied in persons with Alzheimer’s disease (AD). We compared the risk of discontinuation and factors associated with discontinuation, including secondary and primary prevention indication, in statin users with and without AD.

Methods

The register-based Medication Use and Alzheimer’s Disease (MEDALZ) cohort includes community dwellers with a clinically verified AD diagnosed during 2005–2011 in Finland. On the AD diagnosis date (index date), each person with AD was matched with a comparison person without AD. We included 25,137 people with AD and 22,692 without AD who used statin on the index date or initiated within 90 days after. Cox regression models restricted to 4-year follow-up were conducted.

Result

The median time to statin discontinuation was 1.46 years in people with AD and 1.36 years in people without AD. People with AD were more likely to discontinue than people without AD (adjusted HR (aHR) 1.20 (95% CI 1.18–1.24)). This was observed for both primary (aHR 1.11 (1.06–1.16)) and secondary prevention (aHR 1.30 (1.25–1.35)) purpose. Factors associated with discontinuation included higher age and female gender, whereas concomitant cardiovascular drug use and previous statin use were associated with decreased risk.

Conclusion

The absolute difference in discontinuation rates was small, and the same factors were associated with statin discontinuation in people with and without AD. The findings suggest that cognitive decline plays a minor role on statin discontinuation.

Supplementary information

The online version contains supplementary material available at 10.1007/s00228-022-03320-3.