Association of nonsteroidal anti-inflammatory drugs and aspirin with cognitive performance in middle-aged adults

Association Between Non-Steroidal Anti-Inflammatory Drug Use and Cognitive Decline: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most commonly used medications in the elderly. They have been widely studied as possible preventive agents against cognitive decline because of the properties of anti-inflammatories, which sustain cerebral blood flow and mitigate the neurotoxicity of microglial cells. However, the results remain controversial.

OBJECTIVE

Our objective was to assess the effects of NSAID use on the risk of cognitive decline. We reviewed and quantitatively synthesized the evidence from prospective cohort studies via a meta-analysis.

METHODS

We identified pertinent studies by searching the PubMed, EMBASE, and China National Knowledge Infrastructure databases through to December 2015 and by reviewing the reference lists of retrieved articles. We used fixed- or random-effects models to pool relative risks (RRs) with 95 % confidence intervals (CIs) and performed sensitivity analyses to evaluate the robustness of the results. Small-study effect was evaluated using Egger's test and funnel plots.

RESULTS

Of the 2171 articles identified through searching the databases, ten articles including 11 prospective cohort studies were eligible. Overall, NSAID use was associated with a 13 % decreased risk of cognitive decline (pooled RR 0.87; 95 % CI 0.81-0.94). In subgroup analysis, the pooled RRs were 0.89 (95 % CI 0.81-0.98) for follow-up time ≥5 years, 0.85 (95 % CI 0.75-0.96) for follow-up time <5 years, and 0.85 (95 % CI 0.78-0.93) for studies conducted in North America, respectively. Sensitivity analyses found results to be robust. No evidence of significant small-study effect was identified.

CONCLUSIONS

This meta-analysis of prospective cohort studies indicates that NSAID use may be associated with a decreased risk of cognitive decline. Larger, high-quality randomized controlled trials are needed to verify the effects of NSAID use on the risk of cognitive decline.

Acetylsalicylic acid and ascorbic acid combination improves cognition; via antioxidant effect or increased expression of NMDARs and nAChRs?

Chronic inflammation occurs systematically in the central nervous system during ageing, it has been shown that neuroinflammation plays an important role in the pathogenesis of many neurodegenerative disorders. Aspirin, a nonselective COX inhibitor, as well as ascorbic acid, has been purported to protect cerebral tissue. We investigated the effects of subchronic aspirin and ascorbic acid usage on spatial learning, oxidative stress and expressions of NR2A, NR2B, nAChRα7, α4 and β2. Forty male rats (16-18 months) were divided into 4 groups, namely, control, aspirin-treated, ascorbic acid-treated, aspirin+ascorbic acid-treated groups. Following 10-weeks administration period, rats were trained and tested in the Morris water maze. 8-Hydroxy-2-deoxyguanosine and malondialdehyde were evaluated by ELISA and HPLC, respectively. Receptor expressions were assessed by western blotting of hippocampi. Spatial learning performance improved partially in the aspirin group, but significant improvement was seen in the aspirin+ascorbic acid group (p < 0.05). While 8-hydroxy-2-deoxyguanosine and malondialdehyde levels were significantly decreased, NR2B and nAChRα7 expressions were significantly increased in the aspirin+ascorbic acid group as compared to the control group (p < 0.05). Subchronic treatment with aspirin+ascorbic acid in aged rats was shown to enhance cognitive performance and increase the expressions of several receptors related to learning and memory process.

Therapeutic approaches to age-associated neurocognitive disorders

The United Nations projects that the number of individuals with dementia in developed countries alone will be approximately 36,7 million by the year 2050. International recognition of the significant emotional and economic burden of Alzheimer's disease has been matched by a dramatic increase in the development of pharmacological and nonpharmacological approaches to this illness in the past decade. Changing demographics have underscored the necessity to develop similar approaches for the remediation of the cognitive impairment associated with more benign syndromes, such as mild cognitive impairment (MCI) and age-associated cognitive decline (AACD). The present article aims to provide an overview of the most current therapeutic approaches to age-associated neurocognitive disorders. Additionally, it discusses the conceptual and methodological issues that surround the design, implementation, and interpretation of such approaches.

Nonsteroidal anti-inflammatory drugs, aspirin, and cognitive function in the Baltimore longitudinal study of aging

OBJECTIVES

To examine the relations between the use of nonaspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin and age-related change in multiple domains of cognitive function in community-dwelling individuals without dementia.

DESIGN

Longitudinal, with measures obtained on one to 18 occasions over up to 45 years.

SETTING

General community.

PARTICIPANTS

A volunteer sample of up to 2,300 participants from the Baltimore Longitudinal Study of Aging free of diagnosed dementia.

MEASUREMENTS

At each visit, reported NSAID or aspirin use (yes/no) and tests of verbal and visual memory, attention, perceptuo-motor speed, confrontation naming, executive function, and mental status.

RESULTS

Mixed-effects regression models revealed that NSAID use was associated with less prospective decline on the Blessed Information-Memory-Concentration (I-M-C) Test, a mental status test weighted for memory and concentration (P<.001), and Part B of the Trail Making Test, a test of perceptuo-motor speed and mental flexibility (P<.05). In contrast, aspirin use was related to greater prospective decline on the Blessed I-M-C Test (P<.05) and the Benton Visual Retention Test, a test of visual memory (P<.001).

CONCLUSION

Consistent with studies of incident dementia, NSAID users without dementia displayed less prospective decline in cognitive function, but on only two cognitive measures. In contrast, aspirin use was associated with greater prospective cognitive decline on select measures, potentially reflecting its common use for vascular disease prophylaxis. Effect sizes were small, calling into question clinical significance, although overall public health significance may be meaningful.

Alzheimer’s Disease and Vascular Dementia

This chapter explores the frequency with which dementing illnesses occur in populations, their distributions by personal characteristics, and what is known about their causes and potential protective factors. The primary focus is on the most common forms of dementia: Alzheimer's disease and vascular dementia. The chapter summarizes clinical and pathologic features of Alzheimer's disease and vascular dementia, and highlights recent theories of how risk factors affect brain reserve. With the evolution of the epidemiology of dementia from case-control studies to prospective cohort studies has come a new set of methodological challenges. These include identification of representative populations, enhancing subject participation and retention in studies, the need to include institutionalized as well as community-dwelling populations, the non-standardized use of cognitive tests to screen for dementia, and the complexities of the diagnostic process itself. Finally, the chapter summarizes risk and protective factors for disease expression, including cardiovascular risk factors, lifestyle factors, and factors that affect brain reserve.

Novel approaches to preventing chemotherapy-induced cognitive dysfunction in breast cancer: the art of the possible

Chemotherapy-induced cognitive dysfunction in women with breast cancer has become an increasingly important clinical issue. To date, little is known about its incidence, exact characteristics, and exact pathophysiology. Likewise, no treatments have been shown to prevent or decrease cognitive changes thought to result from chemotherapy. However, ongoing scientific research might help us understand the mechanisms that will help patients maintain maximal cognitive function. Changes in cognition due to chemotherapy might result from indirect chemical toxicity and oxidative damage, direct injury to neurons, inflammation, or a type of autoimmune response. Based on these potential causes, and based on interventions that have been tested in dementia and Alzheimer's disease, there are a number of potential, novel interventions that could be tested in clinical trials as treatments for chemotherapy-induced cognitive dysfunction. Possible anecdotal strategies to consider include hormonal interventions, antioxidants, monoamine oxidase inhibitors, growth factors, dopamine agonists, cholinesterase inhibitors, antiinflammatory agents, and behavioral interventions

Achieving and maintaining cognitive vitality with aging

Cognitive vitality is essential to quality of life and survival in old age. With normal aging, cognitive changes such as slowed speed of processing are common, but there is substantial interindividual variability, and cognitive decline is clearly not inevitable. In this review, we focus on recent research investigating the association of various lifestyle factors and medical comorbidities with cognitive aging. Most of these factors are potentially modifiable or manageable, and some are protective. For example, animal and human studies suggest that lifelong learning, mental and physical exercise, continuing social engagement, stress reduction, and proper nutrition may be important factors in promoting cognitive vitality in aging. Manageable medical comorbidities, such as diabetes, hypertension, and hyperlipidemia, also contribute to cognitive decline in older persons. Other comorbidities such as smoking and excess alcohol intake may contribute to cognitive decline, and avoiding these activities may promote cognitive vitality in aging. Various therapeutics, including cognitive enhancers and protective agents such as antioxidants and anti-inflammatories, may eventually prove useful as adjuncts for the prevention and treatment of cognitive decline with aging. The data presented in this review should interest physicians who provide preventive care management to middle-aged and older individuals who seek to maintain cognitive vitality with aging.

Chronic aspirin ingestion improves spatial learning in adult and aged rats

Epidemiological evidence suggests that nonsteroidal, anti-inflammatory drugs (NSAIDs) may retard the progression of Alzheimer's disease (AD). In the present study, we have chronically treated adult (4-5 months old) and aged (20+ months) rats with water adulterated with aspirin, and examined spatial learning in a swim maze. Adult rats (n=40) and aged rats (n=20) were divided into separate groups assigned to receive either normal drinking water or water with 2 mg/ml of aspirin dissolved in it. For 6 weeks, we monitored daily water and/or drug intake before testing all rats in a standard swim maze over an 8-day period. On average, each rat drank approximately 25 ml of water/day with no apparent control versus aspirin group differences. There was no effect of aspirin in young adult rats except during a visible platform trial where aspirin-treated rats performed better than controls. In contrast, aspirin markedly improved performance in the aged rats during hidden and visible platform trials. Such group differences abated by the eighth test day when all rats performed equally well. The improvements in performance were not correlated with changes in swim speeds indicating that the enhancement was not due to facilitated motor output. These data reveal that a modest, 6-week treatment regimen with aspirin in aged rats is sufficient to induce improvements in both speed of learning and strength of the learned response. We have yet to address the key question as to underlying physiological mechanism(s) that might underpin this augmented cognitive performance. Moreover, it would be useful to ascertain whether or not chronic NSAID treatment might reduce the extent of learning impairments in aged, cognitively impaired animals.