'I just take them because I know the people that give them to me': A theory-informed interview study of community-dwelling people with dementia and carers' perspectives of medicines management.

OBJECTIVE: Identify facilitators and barriers to successful medicines management for people with dementia (PwD) in primary care from the perspectives of community-dwelling PwD and carers. METHODS: Semi-structured interviews conducted with PwD and carers in Northern Ireland. The 14-domain Theoretical Domains Framework guided data collection and analysis. Interviews explored participants' experiences and perceptions of medicines management. PwD also completed the Beliefs about Medicines Questionnaire indicating their level of agreement with statements about medicines. Qualitative data were analysed using the framework method and content analysis. Quantitative data were analysed descriptively. RESULTS: Eighteen PwD and 15 carers were interviewed. PwD believed they were competent with medicines management ('beliefs about capabilities'). Most PwD reported having strategies to prompt them to take their medicines ('memory, attention and decision processes'). Carers played an important role in supporting PwD with medicines management ('social influences') and monitoring adherence ('behavioural regulation') and anticipated having to take on a greater role as patients' cognitive impairment worsened ('beliefs about consequences'). Participants highlighted assistance provided by community pharmacies with medicines acquisition and delivery ('environmental context and resources') and placed great trust in primary healthcare professionals ('social influences'). PwD had positive attitudes towards medication and believed strongly in the necessity of their medicines. CONCLUSIONS: This is the first study to use a theoretical approach to explore medicines management for community-dwelling PwD. The findings provide new insights into the critical role of carers in facilitating optimal medicines management and will inform future intervention development, in which carers' needs assessment and involvement will be key.

Improving medicines management for people with dementia in primary care: a qualitative study of healthcare professionals to develop a theory-informed intervention.

BACKGROUND: People with dementia (PwD) face unique challenges with medicines management, yet little is known about these challenges from the perspectives of primary healthcare professionals, particularly general practitioners (GPs) and community pharmacists. Few medicines management interventions have been developed which are aimed at community-dwelling PwD. This study sought to develop an intervention to improve medicines management for PwD in primary care using a theory-informed approach. METHODS: Semi-structured interviews were conducted with GPs (n = 15) and community pharmacists (n = 15) to explore participants' views and experiences of medicines management for PwD, and their perceptions of barriers and facilitators to successful medicines management for PwD. The 14-domain Theoretical Domains Framework was the underpinning theoretical guide, allowing key theoretical domains to be identified and mapped to behaviour change techniques (BCTs) which are considered the 'active ingredients' of an intervention. Draft interventions were developed to operationalise selected BCTs and were presented to GPs and community pharmacists during task groups. Final selection of an intervention for feasibility testing was guided by feedback provided during these task groups and through application of the APEASE (Affordability, Practicability, Effectiveness/cost-effectiveness, Acceptability, Side-effects/safety, Equity) criteria. RESULTS: Participants expressed a number of concerns about medicines management for PwD, particularly monitoring adherence to medication regimens and conducting medication review. Two draft interventions comprising selected BCTs ('Modelling or demonstration of behaviour'; 'Salience of consequences'; 'Health consequences'; 'Social and environmental consequences'; 'Action planning'; Social support or encouragement', 'Self-monitoring of behaviour') were developed, each targeting GPs and community pharmacists. Following the task groups and discussions within the research team, the community pharmacy-based intervention was selected for future feasibility testing. The intervention will target community pharmacists to conduct a medication review (incorporating an adherence check) with a PwD, delivered as an online video demonstrating key behaviours. The video will include feedback emphasising positive outcomes of performing the behaviours. Action planning and a quick reference guide will be used as complementary intervention components. CONCLUSIONS: A community pharmacist-based intervention has been developed targeting medicines management for PwD in primary care using a systematic, theory-informed approach. Future work will determine the usability and acceptability of implementing this intervention in clinical practice.

The development of a Core Outcome Set for medicines management interventions for people with dementia in primary care.

BACKGROUND: people with dementia (PWD), and their carers, face challenges with medicines management activities. As interventions to support medicines management for PWD are developed, consideration must be given to the outcomes chosen to measure their effectiveness. A Core Outcome Set (COS) is a minimum set of outcomes to be measured in all trials in a particular clinical area, which seeks to reduce heterogeneity of outcome reporting across trials. OBJECTIVE: to develop a COS for trials assessing the effectiveness of medicines management interventions for PWD in primary care. METHODS: a comprehensive list of outcomes was compiled through a systematic review and semi-structured interviews with PWD (n = 18), their carers (n = 15), community pharmacists (n = 15) and general practitioners (n = 15). These outcomes were rated by a Delphi panel (n = 52) on a nine-point Likert scale from 1 (limited importance) to 9 (critical) during three sequential rounds of questionnaire distribution. The Delphi panel comprised participants with expertise in dementia and medicines management, including academics and healthcare professionals. An outcome was eligible for inclusion in the COS if ≥70% of participants rated it critical and <15% of participants rated it of limited importance. RESULTS: twenty-nine outcomes identified from the systematic review and stakeholder interviews were presented to the Delphi panel. Consensus was reached on 21 outcomes, of which the 7 most highly rated were recommended for inclusion in the COS. CONCLUSION: this study used robust methodology to develop a COS for medicines management interventions for PWD. Future work should identify the most appropriate tools to measure these outcomes.

Pain in care home residents with dementia: an exploration of frequency, prescribing and relatives' perspectives.

OBJECTIVES: This study aims to determine pain frequency amongst care home residents with dementia, to investigate variables associated with pain, to explore analgesic use among residents and to seek residents' relatives' views on provision of care and management of pain by the care home. METHODS: Structured face-to-face interviews were conducted with residents, nursing staff and relatives from nine dementia care homes in Northern Ireland, between May 2010 and March 2012. Demographic information was collected from participants, neuropsychiatric tests were used to assess residents' cognitive functioning, medication use was determined from care home records and residents' pain was assessed using a verbal descriptor scale. Relatives' views were sought on care provision and management of pain. RESULTS: Forty-two residents, 16 nurses/care assistants and 35 relatives participated; the participation rate of residents was low (27.6%). Most residents were suffering moderate-severe dementia, and some residents (26.2%) were unable to provide a self-report of pain. A significantly higher proportion of relatives (57.1%) deemed residents to be experiencing pain at the time of the interview, compared with residents (23.8%, p = 0.005) and nurses/care assistants (42.9%, p = 0.035). Most residents (88.1%) were prescribed with analgesia; non-opioid analgesics were most commonly prescribed. High proportions of residents were prescribed with psychoactive medications. Antipsychotic drug use was associated with presence of pain (p = 0.046). CONCLUSIONS: This study has reinforced the challenge of assessing and managing pain in this resident population and highlighted issues to be addressed by long-term care providers and clinicians. Participation of people with dementia, and their families, in healthcare research needs to be improved.

Survival in dementia and predictors of mortality: a review.

OBJECTIVE: Dementia is an important cause of mortality and, with the ageing population and increasing prevalence of dementia, reliable data on prognosis and survival will be of interest to patients and caregivers as well as providers and commissioners of health and social care. A review of the literature was undertaken to determine the rates of survival in dementia and Alzheimer's disease (AD) and to identify factors that are or are not predictive of mortality in dementia and AD. METHODS: Relevant articles on mortality in dementia were identified following a search of several electronic databases from 1990 to September 2012. Inclusion criteria were reports on prospective community or clinic based cohorts published in English since 1990, to reflect more recent recognition of possible predictors. RESULTS: Median survival time from age of onset of dementia ranges from 3.3 to 11.7 years, with most studies in the 7 to 10-year period. Median survival time from age of disease diagnosis ranges from 3.2 to 6.6 years for dementia or AD cohorts as a whole. Age was consistently reported as a predictor of mortality, with male gender a less consistent predictor. Increased disease severity and functional impairment were often associated with mortality. CONCLUSIONS: Substantial heterogeneity in the design of included studies limits the ability to prognosticate for individual patients. However, it is clear that dementia and AD are associated with significant mortality. Reasons for the increased mortality are not established.

Community pharmacists and people with dementia: a cross-sectional survey exploring experiences, attitudes, and knowledge of pain and its management.

OBJECTIVES: To explore community pharmacists' experiences with and attitudes towards people with dementia, and to determine the knowledge they have about pain and its management in this patient population. METHODS: A questionnaire comprising five sections, including the Approaches to Dementia Questionnaire, was mailed, on two occasions, during February and March 2011, to all community pharmacies in Northern Ireland (n = 530). RESULTS: The response rate was 34.3%. A greater proportion of pharmacists provided pharmaceutical care to people with dementia living at home (91.2%) than those living in care homes (40.1%). Respondents most frequently encountered queries relating to starting and stopping medications, compliance with medication, and availability of formulation types. The mean total score for the Approaches to Dementia Questionnaire measure was 72.8, indicating a positive attitude towards people with dementia, and respondents demonstrated a strong person-centred approach towards this patient population. The majority of respondents recognised the difficulty of assessing pain in people with dementia; however, younger pharmacists (p = 0.041) and pharmacists who provided pharmaceutical care to people with dementia (p = 0.012) were more likely to be aware of the pain assessment tools for use in people with dementia. Pharmacists appeared uncertain about how to appropriately manage pain in people with dementia. CONCLUSIONS: The study has revealed that community pharmacists often encounter people with dementia, especially those living in their own homes, and they have positive attitudes towards the patient population. However, training in the assessment and management of pain in people with dementia must be developed to further improve their knowledge in this area.

Factors influencing transition to care homes for people with dementia in Northern Ireland.

INTRODUCTION: The increasing number of people with dementia (PwD) is a significant health and financial challenge for countries. PwD often transition to a care home. This study explored factors predicting transition to care homes for PwD and the place and causes of death. METHODS: Data about dementia medication, care home transitions, demographic characteristics, deaths, and hospital admissions were extracted from national databases from 2010 to 2016. RESULTS: PwD (n = 25,418) were identified through prescriptions of dementia medication, from which 11,930 transitioned to care homes. A logistic regression showed that increased age, female sex, living in less deprived and urban areas, and hospital admissions predicted this transition. PwD who transition to care homes are more likely to die there. The most common cause of death was dementia. DISCUSSION: Certain demographic characteristics are significant predictors for care home transitions and they should be considered in the development of early community-based care services to delay transitions. In the last decades, dementia has been reported more frequently in death certificates.

Attention deficits in Alzheimer's disease and vascular dementia.

OBJECTIVE: To compare the performance of patients with mild-moderate Alzheimer's disease (AD) and vascular dementia (VaD) on tests of information processing and attention. METHOD: Patients with AD (n=75) and VaD (n=46) were recruited from a memory clinic along with dementia-free participants (n=28). They underwent specific tests of attention from the Cognitive Drug Research battery, and pen and paper tests including Colour Trails A and B and Stroop. All patients had a CT brain scan that was independently scored for white-matter change/ischaemia. RESULTS: Attention was impaired in both AD and VaD patients. VaD patients had more impaired choice reaction times and were less accurate on a vigilance test measuring sustained attention. Deficits in selective and divided attention occurred in both patient groups and showed the strongest correlations with Mini Mental State Examination scores. CONCLUSION: This study demonstrates problems with the attentional network in mild-moderate AD and VaD. The authors propose that attention should be tested routinely in a memory clinic setting.

Living alone for people on dementia medication: related use of drugs.

Approximately one-third of people with dementia in the United Kingdom live alone. People living alone with dementia may receive different treatment for dementia and may have different comorbidities compared to people who live with a caregiver. This study explored differences in medication and demographic characteristics between people living alone with dementia and those living with a caregiver in Northern Ireland. People with dementia were identified through the first date that a dementia management medication was prescribed between 2010 and 2016. In total, 25,418 people were prescribed a dementia management medication. Data for whether people with dementia lived alone was extracted through the National Health Application and Infrastructure Services and from national datasets through the Honest Broker Service. Approximately 35% (n= 8,828) of people with dementia in Northern Ireland lived alone. People with dementia who lived alone were younger (mean= 75 years, SD= 8.50) compared to people who lived with a caregiver (mean= 77 years, SD= 7.82). Binary logistic regression highlighted that people who lived alone were more likely to be treated with donepezil medication for dementia and less likely to receive antidepressants. These findings indicate that living alone did not affect treatment for dementia and comorbidity medication in people on dementia medication.

A novel reciprocal and biphasic relationship between membrane cholesterol and beta-secretase activity in SH-SY5Y cells and in human platelets.

Research into the cause of Alzheimer's disease (AD) has identified strong connections to cholesterol. Cholesterol and cholesterol esters can modulate amyloid precursor protein (APP) processing, thus altering production of the Abeta peptides that deposit in cortical amyloid plaques. Processing depends on the encounter between APP and cellular secretases, and is thus subject to the influence of cholesterol-dependent factors including protein trafficking, and distribution between membrane subdomains. We have directly investigated endogenous membrane beta-secretase activity in the presence of a range of membrane cholesterol levels in SH-SY5Y human neuroblastoma cells and human platelets. Membrane cholesterol significantly influenced membrane beta-secretase activity in a biphasic manner, with positive correlations at higher membrane cholesterol levels, and negative correlations at lower membrane cholesterol levels. Platelets from individuals with AD or mild cognitive impairment (n = 172) were significantly more likely to lie within the negative correlation zone than control platelets (n = 171). Pharmacological inhibition of SH-SY5Y beta-secretase activity resulted in increased membrane cholesterol levels. Our findings are consistent with the existence of a homeostatic feedback loop between membrane cholesterol level and membrane beta-secretase activity, and suggest that this regulatory mechanism is disrupted in platelets from individuals with cognitive impairment.

Reduced estimated glomerular filtration rate in Alzheimer's disease.

OBJECTIVES: Renal disease is increasingly regarded as an independent risk factor for vascular disease which in itself is believed to influence risk of AD. Alterations in amyloid homeostasis via reduced renal clearance of peripheral beta-amyloid (A|*beta*|) may represent another potential role for variation in renal function leading to increased risk of AD. We sought to examine estimates of glomerular filtration rate in AD and control groups. METHODS: AD patients were randomly recruited from the Memory Clinic of the Belfast City Hospital (n = 83). Genomic DNA was extracted from peripheral leucocytes and was genotyped for Apolipoprotein E using standard methods. Using creatinine values, age and gender, estimated Glomerular Filtration Rates (eGFR) were calculated using the isotope dilution mass spectrometry (IDMS)-traceable Modification of Diet in Renal Disease (MDRD) Study equation (using the United Kingdom National External Quality Assessment Scheme (UKNEQAS) correction factor). IDMS eGFR values were then compared between AD and control groups. RESULTS: Significant baseline differences in age, diastolic blood pressure, education level attained and APOE |*epsilon*|4 carriage were noted between cases and controls. The AD group had a significantly lower eGFR versus controls (69 vs 77 ml/min) which persisted after adjustment for possible confounders (p = 0.045). CONCLUSIONS: This case-control analysis suggests that using a relatively accurate estimate of renal function, patients with AD have greater renal impairment than cognitively normal controls. This may reflect impaired renal clearance of peripheral A|*beta*| or be a marker of shared vascular processes altering cerebral and renal functioning.

Genetically increased risk of sleep disruption in Alzheimer's disease.

STUDY OBJECTIVES: To investigate the role of a monoamine A oxidase promoter polymorphism in sleep disruption in Alzheimer's disease (AD). DESIGN: A case-control association analysis. SETTING: Sleep disturbance in AD is common, is extremely stressful for caregivers, and increases the risk of institutionalisation. It remains unclear why only some patients develop sleep disturbance; neuropathologic changes of AD are not typically seen in the areas of the brain responsible for sleep. We hypothesized that the risk of sleep disturbance is, at least in part, influenced by the availability of serotonin used for melatonin synthesis secondary to polymorphic variation at the enzyme monoamine oxidase A (MAO-A). PATIENTS: Patients with AD diagnosed according to standard criteria. INTERVENTIONS: Data were collected using the Sleep domain of the Neuropsychiatric Inventory with Caregiver Distress. Patients' cognition and function were assessed using the Mini-Mental State Examination and the Functional Assessment Staging. Genotyping of apolipoprotein E (APOE) and of the 30 bp variable number tandem repeat of the MAO-A promoter was by standard methods. MEASUREMENTS AND RESULTS: Of 426 patients surveyed, 54% experienced sleep disturbance. We found that the high-activity 4-repeat allele of the MAO-A VNTR promoter polymorphism confers increased susceptibility to sleep disturbance (p = .008). A quantitative sleep disturbance score was significantly higher in the patients possessing MAO-A 4-repeat allele genotypes. APOE had no influence on the development of an altered sleep phenotype. CONCLUSIONS: We conclude that sleep disturbance in AD is common and distressing and is associated with genetic variation at MAO-A.

Exploring the prevalence of and factors associated with pain: a cross-sectional study of community-dwelling people with dementia.

Few pain studies have made community-dwelling people with dementia (PWD) their focus. The aim of this study was to determine the prevalence of pain among this patient population and to explore medication use. Moreover, we sought to investigate patient and caregiver variables associated with the presence of pain. Community-dwelling PWD and their caregivers were recruited between May 2009 and July 2012 from outpatient memory clinics in Northern Ireland to take part in a face-to-face structured interview with a researcher. Patients' cognitive status and presence of depression were established. A full medication history was taken. Both patients and caregivers were asked to rate patients' pain, at the time of the interview and on an average day, using a 7-point verbal descriptor scale. From the 206 patients who were eligible to take part, 75 patient-caregiver dyads participated in the study (participation rate = 36.4%). The majority of patients (92.0%) had dementia classed as mild or moderate. Pain was commonly reported among the sample, with 57.3% of patients and 70.7% of caregivers reporting patient pain on an average day. Significant differences were found between patients' and caregivers' reports of pain. Two-fifths of patients (40.0%) were prescribed analgesia. Antipsychotic, hypnotic and anxiolytic drug use was low, whereas antidepressant drugs were prescribed more commonly. Presence of pain was unaffected by dementia severity; however, the use of prescribed analgesic medication was a significant predictor of the presence of pain in these patients, whether reported by the patient or their caregiver 'right now' or 'on an average day' (P < 0.001). Patient and caregiver recruitment was challenging, and remains a barrier to research in this area in the future.

Platelet Membrane ß-Secretase Activity in Mild Cognitive Impairment and Conversion to Dementia: a Longitudinal Study.

A blood-based biomarker to complement the clinical and neuropsychological assessments used to evaluate the risk of individuals with mild cognitive impairment (MCI) developing Alzheimer's disease (AD) would be invaluable. Previous pilot studies by our group identified elevated platelet membrane ß-secretase activity in patients with AD and MCI, as compared to controls, and this activity was influenced by membrane cholesterol levels. The present study investigated baseline platelet membrane ß-secretase activity and cholesterol levels in 97 MCI participants and 85 controls and explored whether these parameters differed in individuals with stable MCI, as compared to those who subsequently developed AD. To evaluate signal specificity, ß-secretase activity assays were conducted in the presence and absence of beta-site amyloid-ß protein precursor-cleaving enzyme (BACE) inhibitors. Baseline platelet membrane ß-secretase activity did not differ significantly in MCI participants, as compared to controls, and platelet membrane cholesterol levels were significantly lower in the MCI group. The longitudinal study indicated that the activities inhibited by two different BACE inhibitors did not predict conversion to AD; however, the activity that was not affected by BACE inhibitors was significantly (40%) higher in individuals with stable MCI, as compared with those who subsequently developed AD. These findings indicated that further research into the source of this activity could contribute to a measure facilitating prediction of the risk of conversion from MCI to AD.

Potentially Inappropriate Prescribing Among People with Dementia in Primary Care: A Retrospective Cross-Sectional Study Using the Enhanced Prescribing Database.

BACKGROUND: Little is known about prescribing appropriateness for community-dwelling people with dementia (PWD). OBJECTIVE: To estimate potentially inappropriate prescribing (PIP) prevalence among PWD in primary care in Northern Ireland, and to investigate associations between PIP, polypharmacy, age, and gender. METHODS: A retrospective cross-sectional study was conducted, using data from the Enhanced Prescribing Database. Patients were eligible if a medicine indicated for dementia management was dispensed to them during 1 January 2013-31 December 2013. Polypharmacy was indicated by use of ≥4 repeat medications from different drug groups. A subset of the Screening Tool of Older Persons Potentially Inappropriate Prescriptions (STOPP) criteria, comprising 36 indicators, was applied to the dataset. Overall prevalence of PIP and the prevalence per each STOPP criterion was calculated as a proportion of all eligible persons in the dataset. Logistic regression was used to investigate associations between PIP, polypharmacy, age, and gender. RESULTS: The study population comprised 6826 patients. Polypharmacy was observed in 81.5% (n = 5564) of patients. PIP prevalence during the study period was 64.4% (95% CI 63.2- 65.5; n = 4393). The most common instance of PIP was the use of anticholinergic/antimuscarinic medications (25.2%; 95% CI 24.2-26.2; n = 1718). In multivariable analyses, both polypharmacy and gender (being female) were associated with PIP, with odds ratios of 7.6 (95% CI 6.6-8.7) and 1.3 (95% CI 1.2-1.4), respectively. No association was observed between PIP and age, after adjustments for gender and polypharmacy. CONCLUSION: This study identified a high prevalence of PIP in community-dwelling PWD. Future interventions may need to focus on certain therapeutic categories and polypharmacy.

Cognitive, global, and functional benefits of donepezil in Alzheimer's disease and vascular dementia: results from large-scale clinical trials.

Alzheimer's disease (AD) and vascular dementia (VaD) are both associated with deficits in cholinergic neurotransmission that are amenable to therapeutic intervention. The cholinesterase inhibitor, donepezil, is clinically effective in both AD and VaD. Results from a 10-study metaanalysis of donepezil (5 or 10 mg/day) in AD and a two-study combined analysis of donepezil (5 or 10 mg/day) in VaD are presented to compare patient characteristics and donepezil treatment outcomes. The analyzed studies were randomized, placebo-controlled, and of up to 24 weeks duration. In both AD and VaD, donepezil provided significant benefits compared with placebo on measures of cognition and global function. Placebo-treated AD patients showed a decline in cognition and global function, whereas placebo-treated VaD patients remained stable, suggesting treatment effects of donepezil in VaD were driven by improvement rather than stabilization or reduced decline. More VaD patients than AD patients received concomitant medications. Cardiovascular adverse events were more common in VaD than AD patients but were not increased by donepezil. In conclusion, although there are differences between AD and VaD patients in comorbid conditions and concomitant medications, donepezil is effective and well tolerated in both types of dementia.

Plasma Complement factor H in Alzheimer's Disease.

Biomarkers for Alzheimer's disease (AD) should meet several criteria, including simplicity of testing. Inappropriate activation of the complement cascade has been implicated in the pathogenesis of AD. Complement factor H (CFH) is a regulator of the cascade, but studies on plasma CFH levels in AD have provided mixed results. This study compared plasma CFH levels in 317 AD cases with 254 controls using an immunodiffusion assay. The sample had an 80% power to detect a difference of 23 mg/L between cases and controls, but no difference was evident. Plasma CFH may not be a suitable biomarker for AD.

Moderately elevated plasma homocysteine, methylenetetrahydrofolate reductase genotype, and risk for stroke, vascular dementia, and Alzheimer disease in Northern Ireland.

BACKGROUND AND PURPOSE: Elevated plasma homocysteine level has been associated with increased risk for cardiovascular and cerebrovascular disease. Variation in the levels of this amino acid has been shown to be due to nutritional status and methylenetetrahydrofolate reductase (MTHFR) genotype. METHODS: Under a case-control design we compared fasting levels of homocysteine and MTHFR genotypes in groups of subjects consisting of stroke, vascular dementia (VaD), and Alzheimer disease patients and normal controls from Northern Ireland. RESULTS: A significant increase in plasma homocysteine was observed in all 3 disease groups compared with controls. This remained significant after allowance for confounding factors (age, sex, hypertension, cholesterol, smoking, creatinine, and nutritional measures). MTHFR genotype was not found to influence homocysteine levels, although the T allele was found to increase risk for VaD and perhaps dementia after stroke. CONCLUSIONS: We report that moderately high plasma levels of homocysteine are associated with stroke, VaD, and Alzheimer disease. This is not due to vascular risk factors, nutritional status, or MTHFR genotype.

Allelic variation at the A218C tryptophan hydroxylase polymorphism influences agitation and aggression in Alzheimer's disease.

The behavioural and psychological symptoms of dementia are common, distressing to carers, and directly linked to the requirement for institutional care. Symptoms of aggression and agitation are particularly difficult for carers to tolerate. The origin of these features is unclear although genetic and environmental modification of pre-frontal serotonergic circuitry which regulates the control of negative emotions is proposed. Following the suggestion that the A218C intronic polymorphism of the tryptophan hydroxylase gene influences aggression and anger in non-demented individuals, we tested the influence of A218C on symptoms of agitation/aggression in 396 Alzheimer's disease patients using the Neuropsychiatric Inventory. Overall, 50% of participants experienced agitation/aggression in the month prior to interview. It was observed that male patients with a history of agitation/aggression were more likely to possess C-containing genotypes (P = 0.044, OR = 1.65, CI = 0.98-2.76). We conclude that aggression in male subjects with Alzheimer's disease may be genetically linked to polymorphic variation at the tryptophan hydroxylase gene.

Psychotic symptoms in Alzheimer's disease are not influenced by polymorphic variation at the dopamine receptor DRD3 gene.

It has been suggested that genetic influences unmasked during neurodevelopment to produce schizophrenia may appear throughout neurodegeneration to produce AD plus psychosis. Risk of schizophrenia and psychosis in Alzheimer's disease (AD) has been linked to polymorphic variation at the dopamine receptor DRD3 gene implying similar causative mechanisms. We tested this association in a large cohort of Alzheimer's disease patients with a diagnosis of probable AD of 3 years or more duration from the relatively genetically homogenous Northern Irish population. We assessed relationships between genotypes/alleles of the DRD3 BalI polymorphism and the presence or absence of psychotic symptoms (delusions, hallucinations) in AD patients during the month prior to interview and at any stage during the dementia. No significant associations were found when delusions and hallucinations were cross-tabulated against S and G alleles and SS, SG and GG genotypes. Logistic regression failed to detect any influence of APOE, gender, family history or prior psychiatric history. In conclusion, we were unable to confirm previously reported associations between the DRD3 BalI polymorphism and psychotic symptoms in AD.