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Background: The Australian Imaging, Biomarkers and Lifestyle (AIBL) Study commenced in 2006 as a prospective study of 1,112 individuals (768 cognitively normal (CN), 133 with mild cognitive impairment (MCI), and 211 with Alzheimer’s disease dementia (AD)) as an ‘Inception cohort’ who underwent detailed ssessments every 18 months. Over the past decade, an additional 1247 subjects have been added as an ‘Enrichment cohort’ (as of 10 April 2019). Objective: Here we provide an overview of these Inception and Enrichment cohorts of more than 8,500 person-years of investigation. Methods: Participants underwent reassessment every 18 months including comprehensive cognitive testing, neuroimaging (magnetic resonance imaging, MRI; positron emission tomography, PET), biofluid biomarkers and lifestyle evaluations. Results: AIBL has made major contributions to the understanding of the natural history of AD, with cognitive and biological definitions of its three major stages: preclinical, prodromal and clinical. Early deployment of Aβ-amyloid and tau molecular PET imaging and the development of more sensitive and specific blood tests have facilitated the assessment of genetic and environmental factors which affect age at onset and rates of progression. Conclusion: This fifteen-year study provides a large database of highly characterized individuals with longitudinal cognitive, imaging and lifestyle data and biofluid collections, to aid in the development of interventions to delay onset, prevent or treat AD. Harmonization with similar large longitudinal cohort studies is underway to further these aims.

Background There is a paucity of interventional research that systematically assesses the role of exercise intensity and cardiorespiratory fitness, and their relationship with executive function in older adults. To address this limitation, we have examined the effect of a systematically manipulated exercise intervention on executive function. Methods Ninety-nine cognitively normal participants (age = 69.10 ± 5.2 years; n = 54 female) were randomized into either a high-intensity cycle-based exercise, moderate-intensity cycle-based exercise, or no-intervention control group. All participants underwent neuropsychological testing and fitness assessment at baseline (preintervention), 6-month follow-up (postintervention), and 12-month postintervention. Executive function was measured comprehensively, including measures of each subdomain: Shifting, Updating/ Working Memory, Inhibition, Verbal Generativity, and Nonverbal Reasoning. Cardiorespiratory fitness was measured by analysis of peak aerobic capacity; VO2peak. Results First, the exercise intervention was found to increase cardiorespiratory fitness (VO2peak) in the intervention groups, in comparison to the control group (F =10.40, p≤0.01). However, the authors failed to find mean differences in executive function scores between the high-intensity, moderate intensity, or inactive control group. On the basis of change scores, cardiorespiratory fitness was found to associate positively with the executive function (EF) subdomains of Updating/Working Memory (β = 0.37, p = 0.01, r = 0.34) and Verbal Generativity (β = 0.30, p = 0.03, r = 0.28) for intervention, but not control participants. Conclusion At the aggregate level, the authors failed to find evidence that 6-months of high-intensity aerobic exercise improves EF in older adults. However, it remains possible that individual differences in experimentally induced changes in cardiorespiratory fitness may be associated with changes in Updating/ Working Memory and Verbal Generativity.

The purpose of this investigation was to assess the acute changes in growth factors associated with cognitive health following two ecologically valid, intense resistance exercise sessions. Twenty-nine late-middle-aged adults performed one session of either (a) moderate-load resistance exercise or (b) high-load resistance exercise. Venous blood was collected prior to warm-up, immediately following exercise and 30 min following exercise. Serum was analyzed for brain-derived neurotrophic factor, insulin-like growth factor 1, and vascular endothelial growth factor. Session intensity was determined by blood lactate concentration and session rating of perceived exertion. Postexercise blood lactate was greater following moderate-load when compared with high-load resistance exercise. Subjective session intensity was rated higher by the session rating of perceived exertion following moderate-load when compared with high-load resistance exercise. No differences were observed in serum growth factor levels between groups. Ecologically valid and intense moderate-load or high-load exercise methods do not alter serum growth factor levels in late-middle-aged adults.

Introduction: Evidence suggests that maintaining a higher level of cardiorespiratory fitness (CRF) later in life can offer some protection against brain volume loss as we age. By contrast, mild traumatic brain injury (mTBI) could accelerate age-related cortical atrophy. The current study sought to examine whether variations in the CRF level modified the association between mTBI history and brain volumetric measures in a sample of older adults. Methods: Seventy-nine community-dwelling older adults (mean age 68.7 ± 4.3 years, 54.4% female) were assessed for their mTBI history: 25 participants (32%) reported sustaining at least one lifetime mTBI. Participants also underwent a CRF assessment and magnetic resonance imaging (MRI) to obtain global and region-of-interest volumes. Results: Analysis of covariance, controlling for age, sex, education, and apolipoprotein (APOE) ε4 allele carriage, revealed that participants with a history of mTBI had a significantly larger total mean grey matter volume (582.21 ± 12.46 cm3) in comparison to participants with no mTBI history (571.08 ± 17.21 cm3, p = 0.01 after correction for multiple comparisons). However, no differences between groups based on mTBI history were found for total white matter volume or in any other cortical or subcortical structures examined. A subsequent moderation analysis found that CRF was predominantly non-influential on the association between mTBI history and the MRI-quantified measures of brain volume. Conclusion: While unexpected, the findings suggest that a history of mTBI can lead to grey matter alterations in the ageing brain. However, concurrent variations in the CRF level did not influence the differences in brain volume found based on mTBI exposure status.

BackgroundGrey matter atrophy occurs as a function of ageing and is accelerated in dementia. Previous research suggests physical activity attenuates grey matter loss; however, there appears to be individual variability in this effect. Understanding factors that can affect the relationship between physical activity and brain volume may enable prediction of individual response, and aid in identifying those that gain the greatest neural benefits from physical activity. The current study examined the relationship between objectively-measured physical activity and brain volume; and whether this relationship is moderated by age, sex, or a priori candidate genetic factors.MethodsData from 10,083 men and women (50 years and over) of the UK Biobank were used to examine: 1) the relationship between objectively-measured physical activity and brain volume; and 2) whether the relationship between objectively-measured physical activity and brain volume is moderated by age, sex, brain-derived neurotrophic factor (BDNF) Val66Met, or apolipoprotein (APOE) ε4 allele carriage. All participants underwent a magnetic resonance imaging scan to quantify grey matter volumes, physical activity monitoring via accelerometry, and genotyping.ResultsPhysical activity was associated with total grey matter volume (B = 0.14, p = 0.001, q = 0.005) and right hippocampal volume (B = 1.45, p = 0.008, q = 0.016). The physical activity*sex interaction predicted cortical grey matter (B = 0.22, p = 0.003, q = 0.004), total grey matter (B = 0.30, p < 0.001, q = 0.001), and right hippocampal volume (B = 3.60, p = 0.001, q = 0.002). Post-hoc analyses revealed males received benefit from higher physical activity levels, in terms of greater cortical grey matter volume (B = 0.13, p = 0.01), total grey matter volume (B=0.23, p < 0.001), and right hippocampal volume (B = 3.05, p = 0.008). No moderating effects of age, APOE ε4 allele carriage, or BDNF Val66Met genotype were observed.DiscussionOur results indicate that in males, but not females, an association exists between objectively-measured physical activity and grey matter volume. Future research should evaluate longitudinal brain volumetrics to better understand the nature of sex-effects on the relationship between physical activity and brain volume.

Objectives: To examine the associations between physical activity duration and intensity, cardiorespiratory fitness, and executive function in older adults. Methods: Data from 99 cognitively normal adults (age = 69.10 ± 5.1 years; n = 54 females) were used in the current study. Physical activity (intensity and duration) was measured with the International Physical Activity Questionnaire, and fitness was measured by analysis of maximal aerobic capacity, VO2peak. Executive function was measured comprehensively, including measures of Shifting, Updating, Inhibition, Generativity, and Nonverbal Reasoning. Results: Higher levels of cardiorespiratory fitness were associated with better performance on Generativity (B = .55; 95% confidence interval [.15, .97]). No significant associations were found between self-reported physical activity intensity/duration and executive functions. Discussion: To our knowledge, this study is the first to identify an association between fitness and Generativity. Associations between physical activity duration and intensity and executive function requires further study, using objective physical activity measures and longitudinal observations.

Background The highly encouraging findings from the Finnish Geriatric Intervention Study (known as FINGER) led to the global initiative for dementia risk reduction known as world-wide FINGERS (WW FINGERS). As part of the collaboration, our Australian AU-ARROW trial will follow the general protocol of the FINGER trial, and will also be aligned with the U.S. arm of the study, US-POINTER, though will have minor cultural and dietary modifications to determine the validity of the intervention in an Australian setting. Method AU-ARROW is a randomised, single-blind 2-year clinical trial that will recruit 600 participants aged 60-79 satisfying specific inclusion/exclusion criteria, including normal cognition and one or more cardiovascular risk factors that place them at greater risk of cognitive decline. Participants will be distributed across two sites (a) Macquarie University Health Clinics, Sydney, NSW and (b) Sarich Neuroscience Research Institute, Edith Cowan University, Perth, WA, and will be randomised equally into either the innovative multi-modal intervention group or the study control group, who will receive general lifestyle advice and annual health check-ups, without treatment. Multi-modal intervention consists of aerobic exercise, resistance training and stretching; dietary advice with monitoring to encourage adherence to the MIND diet; cognitive training sessions via the Brain HQ computerised online training system; and medical monitoring and regular health education sessions. Heart rate trackers, diet and exercise log books, and the monitoring of Brain HQ sessions will all help with adherence. Primary outcome measure is improvement in global cognitive score, measured using neurocognitive tests identical to those in the US-POINTER protocol. Additional neurocognitive tests, physical function improvements, detailed diet monitoring and sleep monitoring will provide added data. The unique extra value of AU-ARROW trial consists of the testing for Alzheimer’s disease (AD) blood biomarkers in all participants; as well as the AD Aβ amyloid-specific ligand-PET imaging, brain MRI and retinal biomarker tests that half of the participants will undergo. These tests will provide comprehensive data which have the ultimate purpose of increasing knowledge of the preclinical stages of AD, and help not only to develop preclinical AD diagnostic tests but also efficacy of AU-ARROW’s intervention.

The high prevalence of sleep disruption among older adults may have implications for cognitive aging, particularly for higher-order aspects of cognition. One domain where sleep disruption may contribute to age-related deficits is prospective memory-the ability to remember to perform deferred actions at the appropriate time in the future. Community-dwelling older adults (55-93 years, N = 133) undertook assessment of sleep using actigraphy and participated in a laboratory-based prospective memory task. After controlling for education, sleep disruption (longer awakenings) was associated with poorer prospective memory. Additionally, longer awakenings mediated the relationship between older age and poorer prospective memory. Other metrics of sleep disruption, including sleep efficiency and wake after sleep onset, were not related to prospective memory, suggesting that examining the features of individual wake episodes rather than total wake time may help clarify relationships between sleep and cognition. The mediating role of awakening length was partially a function of greater depression and poorer executive function (shifting) but not retrospective memory. This study is among the first to examine the association between objectively measured sleep and prospective memory in older adults. Furthermore, this study is novel in suggesting sleep disruption might contribute to age-related prospective memory deficits; perhaps, with implications for cognitive aging more broadly. Our results suggest that there may be opportunities to prevent prospective memory decline by treating sleep problems.

Numerous animal studies have reported exercise reduces the accumulation of Alzheimer's disease pathology, including amyloid-β (Aβ) and tau. Furthermore, we previously reported a relationship between higher levels of physical activity (PA) and lower brain Aβ burden in a human population. The recent advent of tau positron emission tomography (PET) tracers enables us to extend our investigations into the evaluation of the relationship between PA and brain tau burden. Utilizing data from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study, we have examined the cross-sectional relationship between habitual PA and PET-quantified tau burden. Forty-three cognitively healthy older adults were categorized into low-moderate PA (LMPA; n = 16) or high PA (HPA; n = 27), based on self-reported PA levels. Tau PET imaging with the AV1451 tracer was conducted on all participants. The LMPA group had significantly higher neocortical tau burden (presented as a z-score; 1.22±1.98), compared to the HPA group (z-score: - 0.28±1.18). The difference between the LMPA and HPA groups was also evident when examining regional tau burden in the temporoparietal cortex and the prefrontal cortex. Our results suggest an association between self-reported PA level and brain tau burden. Future longitudinal and interventional studies utilizing larger samples sizes are vital to further investigate the nature of the relationship between tau and PA.

Worldwide there are over 46 million people living with dementia, and this number is expected to double every 20 years reaching about 131 million by 2050. The cost to the community and government health systems, as well as the stress on families and carers is incalculable. Over three decades of research into this disease have been undertaken by several research groups in Australia, including work by our original research group in Western Australia which was involved in the discovery and sequencing of the amyloid-β peptide (also known as Aβ or A4 peptide) extracted from cerebral amyloid plaques. This review discusses the journey from the discovery of the Aβ peptide in Alzheimer’s disease (AD) brain to the establishment of pre-clinical AD using PET amyloid tracers, a method now serving as the gold standard for developing peripheral diagnostic approaches in the blood and the eye. The latter developments for early diagnosis have been largely achieved through the establishment of the Australian Imaging Biomarker and Lifestyle research group that has followed 1,100 Australians for 11 years. AIBL has also been instrumental in providing insight into the role of the major genetic risk factor apolipoprotein E ɛ4, as well as better understanding the role of lifestyle factors particularly diet, physical activity and sleep to cognitive decline and the accumulation of cerebral Aβ.

Accumulating evidence suggests a diet high in protein and fiber may confer some protection against Alzheimer's disease (AD). However, no human studies to-date have assessed the relationship between protein and fiber intake, and plasma and brain amyloid-β (Aβ). Consequently, this cross-sectional study, investigated the association of self-reported dietary intakes of protein and fiber, with plasma and brain Aβ burden (n = 541, and n = 162 respectively), in a well-characterized cohort of cognitively normal older adults, drawn from the larger Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging. We observed 12.59 and 8.43 higher odds of 'high' brain Aβ burden (PiB PET SUVR≥1.5) if protein intake fell in the lowest and middle tertile, respectively, compared to the highest tertile (p = 0.008; p = 0.013). Thus, in this cohort, the more protein consumed, the less likelihood of 'high' Aβ burden in the brain. No other significant associations were observed. The results of this study highlight the potentially protective impact of high dietary protein intake on brain Aβ burden in older adults, before objective memory decline is apparent. While longitudinal validation is required, these findings may assist in the development of dietary approaches aimed at preventing or delaying AD onset.

The global population is aging at an unprecedented rate giving rise to a greater prevalence of age-related illnesses such as dementia and vascular disease. Dementia affects approximately 47 million individuals globally with projections of 130 million by the year 2050. Late-onset Alzheimer's disease is the most common form of dementia, accounting for approximately 75% of all cases and is characterized by a progressive decline in cognitive function, memory, and cerebral volume. The pathogenesis of Alzheimer's disease is poorly understood; however, aging, genetics, and an individual's diet and lifestyle over several decades appear to be key determinants. As there is no current cure for Alzheimer's disease, postponing or preventing the onset of Alzheimer's disease and dementia through therapeutic methods should, therefore, be targeted at individuals decades prior to an individual showing signs or symptoms of decline. As a preventative tool, resistance exercise improves memory, attention, spatial awareness, reaction time, planning, and information processing. Improvements in cognitive performance following resistance exercise and training may be mediated by peripheral elevations in the physiological biomarkers (i.e., neural and vascular) explored in this review. The purpose of this review is to discuss vascular and neuronal degeneration as a cause or consequence of dementia and Alzheimer's disease, and the biological markers of neurogenesis and blood vessel growth, function, and regulation. We will also explore the merits of acute and chronic resistance training as a strategy to postpone the onset of cognitive decline, dementia, and Alzheimer's disease.

Background:This study investigated the characteristics of subjective memory complaints (SMCs) and their association with current and future cognitive functions.Methods:A cohort of 209 community-dwelling individuals without dementia aged 47–90 years old was recruited for this 3-year study. Participants underwent neuropsychological and clinical assessments annually. Participants were divided into SMCs and non-memory complainers (NMCs) using a single question at baseline and a memory complaints questionnaire following baseline, to evaluate differential patterns of complaints. In addition, comprehensive assessment of memory complaints was undertaken to evaluate whether severity and consistency of complaints differentially predicted cognitive function.Results:SMC and NMC individuals were significantly different on various features of SMCs. Greater overall severity (but not consistency) of complaints was significantly associated with current and future cognitive functioning.Conclusions:SMC individuals present distinctive features of memory complaints as compared to NMCs. Further, the severity of complaints was a significant predictor of future cognition. However, SMC did not significantly predict change over time in this sample. These findings warrant further research into the specific features of SMCs that may portend subsequent neuropathological and cognitive changes when screening individuals at increased future risk of dementia.

Background and Objective:Aberrant lipid metabolism has been implicated in sporadic Alzheimer’s disease (AD). The current study investigated plasma phospholipid and sphingolipid profiles in individuals carrying PSEN1 mutations responsible for autosomal dominant AD (ADAD). Methods:Study participants evaluated were from the Perth and Melbourne sites of the Dominantly Inherited Alzheimer Network (DIAN) study. Plasma phospholipid and sphingolipid profiles were measured using liquid chromatography coupled with mass spectrometry in 20 PSEN1 mutation carriers (MC; eight of whom were symptomatic and twelve asymptomatic, based on Clinical Dementia Rating scores) and compared with six non carriers (NC) using linear mixed models. Further, AD gold standard biomarker data obtained from the DIAN database were correlated with lipid species significantly altered between MC and NC, using Spearman’s correlation coefficient. Results:One-hundred and thirty-nine plasma phospholipid and sphingolipid species were measured. Significantly altered species in MC compared to NC primarily belonged to choline and ethanolamine containing phospholipid classes and ceramides. Further phosphatidylcholine species (34:6, 36:5, 40:6) correlated with cerebrospinal fluid tau (p < 0.05), and plasmalogen ethanolamine species (34:2, 36:,4) correlated with both cerebrospinal fluid tau and brain amyloid load within the MC group (p < 0.05). Conclusion:These findings indicate altered phospholipid and sphingolipid metabolism in ADAD and provide insight into the pathomolecular changes occurring with ADAD pathogenesis. Further, findings reported in this study allow comparison of lipid alterations in ADAD with those reported previously in sporadic AD. The findings observed in the current pilot study warrant validation in the larger DIAN cohort.

(11)C-Pittsburgh compound B (PiB) is a positron emission tomography (PET) tracer designed to bind to amyloid-β (Aβ) plaques, one of the hallmarks of Alzheimer's disease (AD). The potential of PiB as an early marker of AD led to the increasing use of PiB in clinical research studies and development of several F-18-labeled Aβ radiotracers. Automatic quantification of PiB images requires an accurate parcellation of the brain's gray matter (GM). Typically, this relies on a coregistered magnetic resonance imaging (MRI) to extract the cerebellar GM, compute the standardized uptake value ratio (SUVR), and provide parcellation and segmentation for quantification of regional and global SUVR. However, not all subjects can undergo MRI, in which case, an MR-less method is desirable. In this study, we assess 3 PET-only quantification methods: a mean atlas, an adaptive atlas, and a multi-atlas approaches on a database of 237 subjects having been imaged with both PiB PET and MRI. The PET-only methods were compared against MR-based SUVR quantification and evaluated in terms of correlation, average error, and performance in classifying subjects with low and high Aβ deposition. The mean atlas method suffered from a significant bias between the estimated neocortical SUVR and the PiB status, resulting in an overall error of 5.6% (R(2) = 0.98), compared with the adaptive and multi-atlas approaches that had errors of 3.06% and 2.74%, respectively (R(2) = 0.98), and no significant bias. In classifying PiB-negative from PiB-positive subjects, the mean atlas had 10 misclassified subjects compared with 0 for the adaptive and 1 for the multi-atlas approach. Overall, the adaptive and the multi-atlas approaches performed similarly well against the MR-based quantification and would be a suitable replacements for PiB quantification when no MRI is available.

Introduction The objective of this study was to evaluate the relationship between self-reported exercise levels and Alzheimer's disease (AD) biomarkers, in a cohort of autosomal dominant AD mutation carriers. Methods In 139 presymptomatic mutation carriers from the Dominantly Inherited Alzheimer Network, the relationship between self-reported exercise levels and brain amyloid load, cerebrospinal fluid (CSF) Aβ 42, and CSF tau levels was evaluated using linear regression. Results No differences in brain amyloid load, CSF Aβ 42 , or CSF tau were observed between low and high exercise groups. Nevertheless, when examining only those already accumulating AD pathology (i.e., amyloid positive), low exercisers had higher mean levels of brain amyloid than high exercisers. Furthermore, the interaction between exercise and estimated years from expected symptom onset was a significant predictor of brain amyloid levels. Discussion Our findings indicate a relationship exists between self-reported exercise levels and brain amyloid in autosomal dominant AD mutation carriers.

Background It is common for older adults to experience decline in some cognitive functions with increasing age. Importantly, a subset, usually referred to as super-agers (SA; Rogalski, et al., 2013, J Cog Neurosc, 25: 29-36) live to an old age whilst continuing to maintain cognitive function at levels similar to demographically-matched peers at least 20-30 years their junior. The current study reports trajectories of change in cortical thickness on a well-defined group of SAs vs. typical agers (TA) followed longitudinally over six years in the Australian Imaging, Biomarkers & Lifestyle Study (AIBL) (Ellis et al., 2009, Int Psychogeriat, 2: 672-87). Methods Super-Agers were defined as individuals aged 60+ who scored in the normative range for individuals aged 30 – 44 on the CVLT-II, a test of verbal episodic memory, at baseline and two consecutive time-points 18 months apart. SAs additionally must have performed in the unimpaired range in all other cognitive domains, as compared to same-aged peers. Typical agers must have scored within the normal range on all cognitive measures compared with same-aged peers. This report describes data from 21 SAs and 24 TAs. The TAs were chosen from a larger group matched on age, education and gender to the SA group. All participants completed brain magnetic resonance imaging every 18 months for six years. We conducted multiple linear mixed models analyses to assess the association between preservation of cortical thickness in SAs and TAs. Results From 34 regions of interest identified as potentially differentiating SAs from TAs from previous neuroimaging studies, our results were consistent in finding greater cortical thinning amongst TAs in 20 of these regions (p-values ranging between ≤ .000 and .047), with an additional five regions at trend level (p-values ranging between ≥ .05 and .073). Using false discovery rates, we found significantly preserved thickness in three regions not previously reported including left superior parietal gyrus, left precuneus, and left paracentral lobule. Conclusions SAs and TAs displayed similar cortical thickness at baseline (p >.40), but showed different trajectories over time. The findings will be discussed in the context of current models of cognitive and brain reserve.

Amyloid-beta (Abeta) plays a central role in the pathogenesis of Alzheimer's disease (AD) and has been postulated as a potential biomarker for AD. However, there is a lack of consensus as to its suitability as an AD biomarker. The objective of this study was to determine the significance of plasma Abeta as an AD biomarker and its relationship with Abeta load and to determine the effect of different assay methods on the interpretation of Abeta levels. Plasma Abeta1-40, Abeta1-42, and N-terminal cleaved fragments were measured using both a commercial multiplex assay and a well-documented ELISA in 1032 individuals drawn from the well-characterized Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging. Further, Abeta levels were compared to Abeta load derived from positron-emission tomography (PET) with the Pittsburgh compound B (PiB). Lower Abeta1-42 and Abeta1-42/1-40 ratio were observed in patients with AD and inversely correlated with PiB-PET derived Abeta load. However, assay methodology significantly impacted the interpretation of data. The cross-sectional analysis of plasma Abeta isoforms suggests that they may not be sufficient per se to diagnose AD. The value of their measurement in prognosis and monitoring of AD interventions needs further study, in addition to future longitudinal comparisons together with other predictors, which will determine whether plasma Abeta has diagnostic value in a panel of biomarkers.

Background: Currently post-mortem autopsy is the only definitive diagnosis for Alzheimer's disease (AD), while pre-mortem biomarkers in the cerebrospinal fluid and neuroimaging are invasive and uneconomical. This study compares plasma phospholipid profiles in individuals destined to develop AD (carry a mutation responsible for autosomal dominant AD; MC) with those who are non-carriers of the mutations (NC). In addition to providing insight into the pathogenesis of AD, this study allows monitoring of pathogenic phospholipid changes several years before the onset of AD; thus enabling identification of candidate phospholipids as potential diagnostic biomarkers. Methods: Participants belonged to Perth and Melbourne sites of the multicentre Dominantly Inherited Alzheimer Network (DIAN) study. The plasma phospholipid profiles of twenty-eight mutation carriers were compared against sixteen non-carriers. Plasma phospholipids were extracted by the modified Bligh and Dyer method and run on a QTRAP 4000 mass spectrometer via targeted flow injection using multiple reaction monitoring method. Results: Two-hundred and forty phospholipid species were detected, belonging to six major phospholipid classes. Phospholipid species primarily belonging to the lysophosphatidylcholine group were significantly increased in mutation carriers compared to non-carriers (p