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Subject: search.filters.subject.Cognition disorders in old age

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    Ageing, cognition and omega-3 fatty acids : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand
    (Massey University, 2018) Mengelberg, Alexia
    The evidence for omega-3 polyunsaturated fatty acids (n-3 PUFA) in fish oil supplements being a safe therapeutic agent is steadily growing. However, there is still a lack of evidence around the cognitive effects of n-3 PUFAs in older adults with Mild Cognitive Impairment (MCI), the moderating effect of the Apolipoprotein E (APOE) ɛ4 allele on cognition and well-being, and the popularity of fish oil supplements in New Zealand (NZ). The primary aim of this thesis was to conduct a clinical trial to investigate the cognitive effects of a high dose docosahexaenoic acid (DHA) fish oil supplement in older adults with MCI, and to examine how the presence of the APOE ɛ4 allele affects the efficacy of fish oil. The trial involved a 12-month randomised, double-blind, placebo-controlled design with testing sessions at baseline, 6-months, 9-months and at the end of the trial. Seventy-two adults with MCI between the ages of 60 and 90 were recruited from Wellington, NZ. Participants were either given a DHA fish oil supplement containing 1491 mg of DHA and 351 mg of eicosapentaenoic acid (EPA) per day or a placebo supplement containing sunflower oil. Outcome measures included the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the National Adult Reading Test (NART), the Coin Rotation Task (CRT), the California Older Adult Stroop Test (COAST), the Trail Making Test A and B (TMT), Digit Span Backwards Test (DSBT), the Geriatric Depression Scale (GDS), the Geriatric Anxiety Inventory (GAI), the 36-Item Short Form Health Survey Questionnaire (SF-36), height, weight and blood pressure as well as red blood cell (RBC) fatty acid profiles. ANCOVAs, t-tests and chi-square tests were used to test for differences between the DHA and placebo groups. The secondary aim of this thesis was to conduct an online cross-sectional survey to investigate how popular fish oil supplements are within a sample population of New Zealanders, to determine why fish oil supplements are used, what dose fish oil users take, and where fish oil users store their supplements. The aim of the survey was to test the hypothesis that fish oil users are more likely to display healthier dietary and lifestyle habits. The final analysis (n = 60) of the trial found no evidence of a treatment effect using the cognitive measures, although it did find a treatment effect on systolic blood pressure (p = .03, ƞ2 = .08), and a treatment interaction for APOE ɛ4 carriers on depression (p = .04, ƞ2= .07) and anxiety (p = .02, ƞ2 = .09) scores in favour of the DHA group. The survey found that in a sample of 334 New Zealanders, 66.8% reported using supplements and 21.9% reported using fish oil supplements. The survey found that respondents who regularly eat oily fish are most likely to take fish oil supplements (p < .01), and that only 26% of fish oil users reported taking a dose that would meet dietary recommendations. Over half of fish oil users reported taking fish oils to ‘improve brain functioning’ and only 6.8% of fish oil users reported storing fish oil supplements in the refrigerator. The evidence from epidemiological studies suggests that fish consumption is protective against cognitive decline and dementia, and yet the evidence from clinical trials investigating the cognitive effects of n-3 PUFAs in older adults has been inconsistent and at times conflicting. It appears that the protective effect of fish may be more than the n-3 PUFA content, and that fish consumption may be part of an overall healthier diet and lifestyle, along with regular physical activity, strong social connections and an emphasis on educational attainment and engagement in cognitive activities.
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    "Where did I park my car?" : a mixed methods investigation on mild cognitive impairment diagnosis in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of a Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand
    (Massey University, 2015) McKinlay, Alison R
    Mild cognitive impairment (MCI) is defined as an objective impairment in cognitive function which spares everyday functional ability. The syndrome is shrouded in controversy regarding definition, cut-off criteria, and clinical utility. Consequently, it is an uncertain label for the client being diagnosed by their healthcare practitioner. To date, minimal research in New Zealand has focused on MCI within specialist assessment services. Reasons for this paucity of literature will be discussed throughout this thesis. The current research aimed to identify how practitioners deliver and perceive cognitive impairment diagnosis, and examine how clients respond to receiving this diagnosis. Client experiences were framed within the common sense model (CSM). This theory originates from health psychology, where coping behaviour is said to be influenced by the cognitive representations that a person has about their condition. Although the framework is previously discussed in relation to chronic illness, international researchers have started to examine the utility of the model in explaining MCI diagnosis response. Given this context, the CSM framework guided the client-focused components of this thesis. In Study One, 57 practitioners who diagnose cognitive impairment completed a questionnaire on labels applied to MCI and beliefs about the value of diagnosis delivery. Responses were analysed using content analysis to gain an impression of professional practice. Cognitive disorder - not otherwise specified (CD-NOS), early dementia, and normal ageing were reported to additionally label the symptoms of MCI in clinical practice. In Study Two, client responses were examined in a small clinical sample (N = 9) diagnosed with MCI and CD-NOS. Participants were interviewed twice within six months of initial diagnosis. Interpretative phenomenological analysis was used to gain insight into how people cope and make sense of their diagnosis over time. Descriptive analyses were also undertaken with a subset of Study Two data to examine changes and differences in coping strategies over time. Findings suggest that participants may not see their diagnosis as an illness or significant health threat in the first six months following diagnosis. This prompts a question on the suitability of an illness model with reference to diagnosis response. Findings from this research add to the literature by highlighting practice associated with an evolving form of clinical diagnosis in NZ.
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    Comparing group-based interventions in older adults with subjective memory difficulties : a dissertation presented in partial fulfilment of the requirements for the degree of Doctorate in Clinical Psychology, Massey University, Wellington, New Zealand
    (Massey University, 2014) Sothieson, Veena
    The trend internationally and within New Zealand is of an increasing aging population, with numbers of those with dementia projected to increase rapidly. One way to address this issue is to consider the practical and clinical benefits of running memory intervention groups for older adults with memory difficulties/impairment. The current study intended to address some of the limitations found in memory intervention literature by (a) using a social control group as a control comparison, which has not been done before, and (b) separating out components of memory training interventions (i.e., memory strategies and lifestyle education). Therefore, the aim was to determine the extent to which receiving Memory intervention separately from a Lifestyle Education intervention would affect memory functioning in older adults with subjective memory difficulties, when compared with a social control condition. Participants for the intervention group were recruited from rest homes and retirement villages, while social control participants were community-dwelling older adults already taking part in weekly community group activities. A brief cognitive screen and subjective outcome measures were administered at baseline, post Phase 1, post Phase 2, and at six month follow-up. Quantitative and qualitative information from a total of 13 participants were analysed. Results from each of the outcome measures across the four time points indicated that there were no significant benefits of receiving Memory and/or Lifestyle Education interventions, when compared with a social control condition. However, a small sample size, non-equivalent groups, and lack of random assignment were some of the limitations which made it difficult to reach definite conclusions. Content analysis of qualitative information following intervention sessions provided some valuable considerations for running memory groups in future. In light of its limitations, the current study highlights practical considerations and recommendations for future research in this area. In particular, it identifies the value of conducting memory intervention research with older adults in residential care settings.