Genome-wide analyses as part of the international FTLD-TDP whole-genome sequencing consortium reveals novel disease risk factors and increases support for immune dysfunction in FTLD.

Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) represents the most common pathological subtype of FTLD. We established the international FTLD-TDP whole-genome sequencing consortium to thoroughly characterize the known genetic causes of FTLD-TDP and identify novel genetic risk factors. Through the study of 1131 unrelated Caucasian patients, we estimated that C9orf72 repeat expansions and GRN loss-of-function mutations account for 25.5% and 13.9% of FTLD-TDP patients, respectively. Mutations in TBK1 (1.5%) and other known FTLD genes (1.4%) were rare, and the disease in 57.7% of FTLD-TDP patients was unexplained by the known FTLD genes. To unravel the contribution of common genetic factors to the FTLD-TDP etiology in these patients, we conducted a two-stage association study comprising the analysis of whole-genome sequencing data from 517 FTLD-TDP patients and 838 controls, followed by targeted genotyping of the most associated genomic loci in 119 additional FTLD-TDP patients and 1653 controls. We identified three genome-wide significant FTLD-TDP risk loci: one new locus at chromosome 7q36 within the DPP6 gene led by rs118113626 (p value = 4.82e - 08, OR = 2.12), and two known loci: UNC13A, led by rs1297319 (p value = 1.27e - 08, OR = 1.50) and HLA-DQA2 led by rs17219281 (p value = 3.22e - 08, OR = 1.98). While HLA represents a locus previously implicated in clinical FTLD and related neurodegenerative disorders, the association signal in our study is independent from previously reported associations. Through inspection of our whole-genome sequence data for genes with an excess of rare loss-of-function variants in FTLD-TDP patients (n ≥ 3) as compared to controls (n = 0), we further discovered a possible role for genes functioning within the TBK1-related immune pathway (e.g., DHX58, TRIM21, IRF7) in the genetic etiology of FTLD-TDP. Together, our study based on the largest cohort of unrelated FTLD-TDP patients assembled to date provides a comprehensive view of the genetic landscape of FTLD-TDP, nominates novel FTLD-TDP risk loci, and strongly implicates the immune pathway in FTLD-TDP pathogenesis.

Association Between Anticholinergic Medication Use and Cognition, Brain Metabolism, and Brain Atrophy in Cognitively Normal Older Adults.

IMPORTANCE: The use of anticholinergic (AC) medication is linked to cognitive impairment and an increased risk of dementia. To our knowledge, this is the first study to investigate the association between AC medication use and neuroimaging biomarkers of brain metabolism and atrophy as a proxy for understanding the underlying biology of the clinical effects of AC medications. OBJECTIVE: To assess the association between AC medication use and cognition, glucose metabolism, and brain atrophy in cognitively normal older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI) and the Indiana Memory and Aging Study (IMAS). DESIGN, SETTING, AND PARTICIPANTS: The ADNI and IMAS are longitudinal studies with cognitive, neuroimaging, and other data collected at regular intervals in clinical and academic research settings. For the participants in the ADNI, visits are repeated 3, 6, and 12 months after the baseline visit and then annually. For the participants in the IMAS, visits are repeated every 18 months after the baseline visit (402 cognitively normal older adults in the ADNI and 49 cognitively normal older adults in the IMAS were included in the present analysis). Participants were either taking (hereafter referred to as the AC+ participants [52 from the ADNI and 8 from the IMAS]) or not taking (hereafter referred to as the AC- participants [350 from the ADNI and 41 from the IMAS]) at least 1 medication with medium or high AC activity. Data analysis for this study was performed in November 2015. MAIN OUTCOMES AND MEASURES: Cognitive scores, mean fludeoxyglucose F 18 standardized uptake value ratio (participants from the ADNI only), and brain atrophy measures from structural magnetic resonance imaging were compared between AC+ participants and AC- participants after adjusting for potential confounders. The total AC burden score was calculated and was related to target measures. The association of AC use and longitudinal clinical decline (mean [SD] follow-up period, 32.1 [24.7] months [range, 6-108 months]) was examined using Cox regression. RESULTS: The 52 AC+ participants (mean [SD] age, 73.3 [6.6] years) from the ADNI showed lower mean scores on Weschler Memory Scale-Revised Logical Memory Immediate Recall (raw mean scores: 13.27 for AC+ participants and 14.16 for AC- participants; P = .04) and the Trail Making Test Part B (raw mean scores: 97.85 seconds for AC+ participants and 82.61 seconds for AC- participants; P = .04) and a lower executive function composite score (raw mean scores: 0.58 for AC+ participants and 0.78 for AC- participants; P = .04) than the 350 AC- participants (mean [SD] age, 73.3 [5.8] years) from the ADNI. Reduced total cortical volume and temporal lobe cortical thickness and greater lateral ventricle and inferior lateral ventricle volumes were seen in the AC+ participants relative to the AC- participants. CONCLUSIONS AND RELEVANCE: The use of AC medication was associated with increased brain atrophy and dysfunction and clinical decline. Thus, use of AC medication among older adults should likely be discouraged if alternative therapies are available.

Treatment options in Alzheimer's disease: maximizing benefit, managing expectations.

Alzheimer's disease (AD) is becoming an increasingly heavy burden on the society of developed countries, and physicians now face the challenge of providing efficient treatment regimens to an ever-higher number of individuals affected by the disease. Currently approved anti-AD therapies - the cholinesterase inhibitors and the N-methyl-D-aspartate receptor antagonist memantine - offer modest symptomatic relief, which can be enhanced using combination therapy with both classes of drugs. Additionally, alternative therapies such as nonsteroidal anti-inflammatory drugs, vitamin E, selegiline, Ginkgo biloba extracts, estrogens, and statins, as well as behavioral and lifestyle changes, have been explored as therapeutic options. Until a therapy is developed that can prevent or reverse the disease, the optimal goal for effective AD management is to develop a treatment regimen that will yield maximum benefits for individual patients across multiple domains, including cognition, daily functioning, and behavior, and to provide realistic expectations for patients and caregivers throughout the course of the disease. This review provides a basic overview of approved AD therapies, discusses some pharmacologic and nonpharmacologic treatment strategies that are currently being investigated, and offers suggestions for optimizing treatment to fit the needs of individual patients.

A randomized, double-blind, placebo-controlled trial of two doses of Ginkgo biloba extract in dementia of the Alzheimer's type.

CONTEXT: Previous studies of Ginkgo biloba extract (GbE) in patients with various forms of cognitive impairment or dementia have shown promising results. OBJECTIVE: To determine the clinical efficacy of GbE in mild to moderate dementia of the Alzheimer type. DESIGN: Randomized, placebo-controlled, double-blind, parallel-group, multicenter trial. SETTING: Outpatient clinics of universities and private research centers specialized in dementia. PATIENTS: 513 outpatients with uncomplicated dementia of the Alzheimer's type scoring 10 to 24 on the Mini-Mental State Examination and less than 4 on the modified Hachinski Ischemic Score, free of other serious illnesses and not requiring continuous treatment with any psychoactive drug. INTERVENTION: 26-week treatment with GbE at daily doses of 120 mg or 240 mg or placebo. MAIN OUTCOMES: Cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog), Alzheimer's Disease Cooperative Study Clinical Global Impression of Change (ADCS-CGIC). RESULTS: There were no significant between-group differences for the whole sample. There was little cognitive and functional decline of the placebo-treated patients, however. For a subgroup of patients with neuropsychiatric symptoms there was a greater decline of placebo-treated patients and significantly better cognitive performance and global assessment scores for the patients on GbE. CONCLUSION: The trial did not show efficacy of GbE, however, the lack of decline of the placebo patients may have compromised the sensitivity of the trial to detect a treatment effect. Thus, the study remains inconclusive with respect to the efficacy of GbE.

Caffeic acid phenethyl ester prevents neonatal hypoxic-ischaemic brain injury.

Neonatal hypoxic-ischaemic (HI) brain injury resulting in encephalopathy is a leading cause of morbidity and mortality with no effective treatment. Here we show that caffeic acid phenethyl ester (CAPE), an active component of propolis, administered either before or after an HI insult, significantly prevents HI-induced neonatal rat brain damage in the cortex, hippocampus and thalamus. In addition to blocking HI-induced caspase 3 activation, CAPE also inhibits HI-mediated expression of inducible nitric oxide synthase and caspase 1 in vivo and potently blocks nitric oxide-induced neurotoxicity in vitro. Furthermore, CAPE directly inhibits Ca2+-induced cytochrome c release from isolated brain mitochondria. Thus, CAPE induces neuroprotection against HI-induced neuronal death, possibly by blocking HI-induced inflammation and/or directly inhibiting the HI-induced neuronal death pathway. CAPE may therefore be a novel effective therapy for preventing neonatal HI injury.