Transmission of Alzheimer's disease-associated microbiota dysbiosis and its impact on cognitive function: evidence from mice and patients.

Spouses of Alzheimer's disease (AD) patients are at a higher risk of developing incidental dementia. However, the causes and underlying mechanism of this clinical observation remain largely unknown. One possible explanation is linked to microbiota dysbiosis, a condition that has been associated with AD. However, it remains unclear whether gut microbiota dysbiosis can be transmitted from AD individuals to non-AD individuals and contribute to the development of AD pathogenesis and cognitive impairment. We, therefore, set out to perform both animal studies and clinical investigation by co-housing wild-type mice and AD transgenic mice, analyzing microbiota via 16S rRNA gene sequencing, measuring short-chain fatty acid amounts, and employing behavioral test, mass spectrometry, site-mutations and other methods. The present study revealed that co-housing between wild-type mice and AD transgenic mice or administrating feces of AD transgenic mice to wild-type mice resulted in AD-associated gut microbiota dysbiosis, Tau phosphorylation, and cognitive impairment in the wild-type mice. Gavage with Lactobacillus and Bifidobacterium restored these changes in the wild-type mice. The oral and gut microbiota of AD patient partners resembled that of AD patients but differed from healthy controls, indicating the transmission of microbiota. The underlying mechanism of these findings includes that the butyric acid-mediated acetylation of GSK3ß at lysine 15 regulated its phosphorylation at serine 9, consequently impacting Tau phosphorylation. Pending confirmative studies, these results provide insight into a potential link between the transmission of AD-associated microbiota dysbiosis and development of cognitive impairment, which underscore the need for further research in this area.

Postoperative Delirium Is Associated with Long-term Decline in Activities of Daily Living.

BACKGROUND: Postoperative delirium is one of the most common complications in the elderly surgical population. However, its long-term outcomes remain largely to be determined. Therefore a prospective cohort study was conducted to determine the association between postoperative delirium and long-term decline in activities of daily living and postoperative mortality. The hypothesis in the present study was that postoperative delirium was associated with a greater decline in activities of daily living and higher mortality within 24 to 36 months after anesthesia and surgery. METHODS: The participants (at least 65 yr old) having the surgeries of (1) proximal femoral nail, (2) hip replacement, or (3) open reduction and internal fixation under general anesthesia were enrolled. The Confusion Assessment Method algorithm was administered to diagnose delirium before and on the first, second, and fourth days after the surgery. Activities of daily living were evaluated by using the Chinese version of the activities of daily living scale (range, 14 to 56 points), and preoperative cognitive function was assessed by using the Chinese Mini-Mental State Examination (range, 0 to 30 points). The follow-up assessments, including activities of daily living and mortality, were conducted between 24 and 36 months after anesthesia and surgery. RESULTS: Of 130 participants (80 ± 6 yr, 24% male), 34 (26%) developed postoperative delirium during the hospitalization. There were 32% of the participants who were lost to follow-up, resulting in 88 participants who were finally included in the data analysis. The participants with postoperative delirium had a greater decline in activities of daily living (16 ± 15 vs. 9 ± 15, P = 0.037) and higher 36-month mortality (8 of 28, 29% vs. 7 of 75, 9%; P = 0.009) as compared with the participants without postoperative delirium. CONCLUSIONS: Postoperative delirium was associated with long-term detrimental outcomes, including greater decline in activities of daily living and a higher rate of postoperative mortality.

Transmission of Alzheimer's Disease-Associated Microbiota Dysbiosis and its Impact on Cognitive Function: Evidence from Mouse Models and Human Patients.

Spouses of Alzheimer's disease (AD) patients are at higher risk of developing AD dementia, but the reasons and underlying mechanism are unknown. One potential factor is gut microbiota dysbiosis, which has been associated with AD. However, it remains unclear whether the gut microbiota dysbiosis can be transmitted to non-AD individuals and contribute to the development of AD pathogenesis and cognitive impairment. The present study found that co-housing wild-type mice with AD transgenic mice or giving them AD transgenic mice feces caused AD-associated gut microbiota dysbiosis, Tau phosphorylation, and cognitive impairment. Gavage with Lactobacillus and Bifidobacterium restored these changes. The oral and gut microbiota of AD patient partners resembled that of AD patients but differed from healthy controls, indicating the transmission of oral and gut microbiota and its impact on cognitive function. The underlying mechanism of these findings includes that the butyric acid-mediated acetylation of GSK3ß at lysine 15 regulated its phosphorylation at serine 9, consequently impacting Tau phosphorylation. These results provide insight into a potential link between gut microbiota dysbiosis and AD and underscore the need for further research in this area.

Case report: Treatment of psychiatric symptoms for an acromegalic patient with pituitary adenoma.

Acromegalic patients always demonstrate a wide range of clinic manifestations, including typical physical changes such as acral and facial features, as well as untypical neuropsychiatric and psychological disturbances. However, there is still a lack of clinical guidance on the treatment for acromegalic patients with psychiatric comorbidities. We therefore share this case to provide a reference for clinicians to manage the acromegalic patients with psychiatric symptoms. This case report describes a 41-year-old male with an 8-year history of acromegaly due to growth hormone-secreting pituitary adenoma, the maximum cross-sectional area of which was 42 mm × 37 mm demonstrated by pituitary magnetic resonance imaging (MRI). The patient received conservative medicine treatment by regularly injecting with Sandostatin LAR 10 mg per month. Two days before admission, he suddenly presented with an acute psychotic episode. In addition to the typical acromegaly-associated changes, his main clinical presentations were olfactory/auditory hallucinations, reference/persecutory delusions, instable emotion and impulsive behavior. Considering the schizophrenic-like psychoses and course features, he was diagnosed with Brief Psychotic Disorder according to Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) after a multidisciplinary consultation and evaluation. He was prescribed Aripiprazole, which had less extrapyramidal symptoms and minimal influence on prolactin elevation, with the dose of 5 mg per day to control the psychiatric symptoms and he responded quite well. At the time of discharge and the follow-up 2 month later, the patient was stable without recurrence of any psychotic symptoms. The levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) 1 week after discharge were 2.22 ng/mL [normal range (0-2.47 ng/mL)] and 381 µg/L [normal range (94-284 µg/L)], respectively, which were similar to those before the psychotic episode. Results from this report further supported that small dose of Aripiprazole had little influence on hormonal levels and the development of pituitary macroadenoma. This particular case emphasizes the importance for the clinician to master and carefully identify the possible symptoms of mental disorders associated with acromegaly, and also highlights the need for further investigation in more efficient treatment strategies for acromegalic cases with psychiatric comorbidities.

Retinal nerve fiber layer thickness is associated with hippocampus and lingual gyrus volumes in nondemented older adults.

OBJECTIVES: Abnormal retina structures, such as thinner retinal nerve fiber layer (RNFL), have been frequently reported in patients with Alzheimer's disease (AD). However, the association between RNFL and brain structures in cognitively normal adults remains unknown. We therefore set out to conduct a cross-sectional investigation to determine whether RNFL thickness is associated with brain structure volumes in nondemented older adults. METHODS: We measured RNFL thickness by optical coherence tomography and brain structure volumes by 3 T magnetic resonance imaging. Cognitive function was assessed using the Chinese version of Repeatable Battery for the Assessment of Neurological Status. Pearson correlation was initially employed to screen for the potential associations among RNFL thickness, brain structure volumes and cognitive function. And then, multivariable linear regression models were conducted to further examine such associations adjusting for possible confounding factors, including age, sex, years of education and the estimated total intracranial volume (eTIV). RESULTS: 113 participants (≥ 65 years old) were screened and 80 of them (mean age: 68 ± 5.3 years; 48% male) were included in the final analysis. RNFL thickness in temporal quadrant was associated with medial temporal lobes volumes [unadjusted: r = 0.155, P = 0.175; adjusted: ß = 0.205 (0.014, 0.383), P = 0.035], and especially associated with the hippocampus volume [unadjusted: r = 0.213, P = 0.062; adjusted: ß = 0.251 (0.060, 0.435), P = 0.011] after adjusted for age, sex, years of education and eTIV. Moreover, it showed that RNFL thickness in inferior quadrant [unadjusted: r = 0.221, P = 0.052; adjusted: ß = 0.226 (0.010. 0.446), P = 0.041] was significantly associated with occipital lobes volumes after the adjustment of age, sex, years of education and eTIV, and selectively associated with the substructure of lingual gyrus volume [unadjusted: r = 0.223, P = 0.050; adjusted: ß = 0.278 (0.058, 0.487), P = 0.014]. In addition, average RNFL thickness was associated with the cognitive domain of visuospatial/constructional [unadjusted: r = 0.114, P = 0.322; adjusted: ß = 0.216 (0.006, 0.426), P = 0.044] after the adjustment in these nondemented older adults. CONCLUSIONS: Quadrant-specific associations exist between RNFL thickness and brain regions vulnerable to aging or neurodegeneration in older adults with normal cognition. These findings would promote further investigations into using RNFL as a noninvasive and less expensive biomarker of neurocognitive aging and AD-related neurodegeneration.

The Reliability and Validity of the Chinese Version of Confusion Assessment Method Based Scoring System for Delirium Severity (CAM-S).

Previous studies showed that the Confusion Assessment Method based delirium severity evaluation tool (CAM-S) had good reliability and validity. However, there is no Chinese version of the CAM-S. Therefore, we set out to perform a prospective investigation in older Chinese patients who had total joint replacement surgery under general anesthesia in Tenth People's Hospital in Shanghai, P.R. China. A total of 576 participants, aged 60 years or older, were screened, 179 participants were enrolled, and 125 of them were included for the final analysis. Pre-operative evaluations were conducted one day before the surgery. Postoperative evaluations were conducted twice daily from postoperative day 1 to day 3. The incidence of postoperative delirium was 24.8%. The Chinese version of CAM-S [including a Short Form (CAM-S Short Form) and a Long Form (CAM-S Long Form)] had an optimal reliability reflected by internal consistency (Cronbach's α= 0.748 and 0.839 for CAM-S Short Form and CAM-S Long Form respectively), split-halves reliability (Pearson correlation coefficient = 0.372 and 0.384 for CAM-S Short Form and CAM-S Long Form respectively), and inter-rater reliability (intra-class correlation coefficients = 0.629 and 0.945 for CAM-S Short Form and CAM-S Long Form respectively). Additionally, the Chinese version of CAM-S also showed a good discriminate validity. The domain scores of CAM-S were inversely correlated with corresponding domain scores of the MMSE. Finally, a receiver operating characteristic (ROC) analysis obtained an optimal cutoff point of 2.5 for CAM-S Short Form and 3.5 for CAM-S Long Form in recognizing delirium diagnosed by CAM. The areas under the ROC were 0.989 (95% CI 0.972 - 1.000, p < 0.001) and 0.964 (95% CI 0.946 - 0.982, p < 0.001), respectively. These data suggest that the Chinese version of CAM-S has good reliability and validity in evaluating postoperative delirium in geriatric Chinese patients and may be a useful tool to assess the severity of delirium.

Retinal Nerve Fiber Layer Thinning Is Associated With Brain Atrophy: A Longitudinal Study in Nondemented Older Adults.

Backgrounds: Abnormal retinal nerve fiber layer (RNFL) thickness has been observed in patients with Alzheimer's disease (AD) and therefore suggested to be a potential biomarker of AD. However, whether the changes in RNFL thickness are associated with the atrophy of brain structure volumes remains unknown. We, therefore, set out a prospective investigation to determine the association between longitudinal changes of RNFL thickness and brain atrophy in nondemented older participants over a period of 12 months. Materials and Methods: We measured the RNFL thickness using optical coherence tomography (OCT) and brain structure volumes by 3T magnetic resonance imaging (MRI) before and after 12 months. Cognitive function was assessed using the Chinese version of Mini-Mental State Examination (CMMSE) and Repeatable Battery for the Assessment of Neurological Status. Associations among the changes of RNFL, brain structures and cognitive function were analyzed with Spearman correlation and multiple linear regression models adjusting for the confounding factors. Results: Fifty old participants were screened and 40 participants (mean age 71.8 ± 3.9 years, 60% were male) were enrolled at baseline. Among them, 28 participants completed the follow-up assessments. The average reduction of RNFL thickness was inversely associated with the decrease of central cingulate cortex volume after the adjustment of age and total intracranial volume (ß = -0.41, P = 0.039). Specifically, the reduction of RNFL thickness in the inferior, not other quadrants, was independently associated with the decline of central cingulate cortex volume after the adjustment (ß = -0.52, P = 0.006). Moreover, RNFL thinning, central cingulate cortex atrophy and the aggregation of white matter hyperintensities (WMH) were found associated with episodic memory in these older adults with normal cognition. Conclusions: RNFL thinning was associated with cingulate cortex atrophy and episodic memory decline in old participants. The longitudinal changes of RNFL thickness are suggested to be a useful complementary index of neurocognitive aging or neurodegeneration.

Multidimensional Approaches for A Case of Severe Adult Obsessive - Compulsive Disorder.

Obsessive-compulsive disorder (OCD) is a chronic, distressing and substantially impairing neuropsychiatric disorder, characterized by obsessions or compulsions. The current case describes a 44-year-old adult female diagnosed with OCD. The patient had an incomplete response to several SSRIs alone during her past treatment, and led a poor-quality life for at least three years. Current multidimensional approaches, including combined cognitive behavioral therapy (CBT) and the Selective Serotonin Reuptake Inhibitor (SSRI, Sertraline) with a small dose of antipsychotics (Aripiprazole) for augmentation, as well as familial support and resources from the internet were provided for the patient for six months. Standardized assessments with Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) every two months indicated significant reductions in obsessive and compulsive symptoms, with significant improvements in her social functioning and quality of life. A case such as this one provides preliminary support to multidimensional approaches for OCD treatment in order to achieve an optimal response, though further rigorous clinical trials are needed to provide more evidence.

Treatment resistant depression or dementia: a case report.

The current case describes a 78-year-old female with two previous episodes of major depression who presented with both symptoms of depression (amotivation and flattened affect) and typical symptoms of dementia (impaired memory and executive functioning). Even after a detailed clinical exam and neuropsychiatric testing, it remained difficult to definitively classify the diagnosis as either treatment-resistant depression or old-age dementia. After 8 weeks of inpatient treatment, including changing her reserpine-based antihypertensive medication, adjusting her antidepressants, and providing psychotherapy, her depressive and anxiety symptoms improved, but most of her cognitive symptoms persisted. Her symptoms did not change over 7 months of post-hospitalization follow-up. She subsequently developed advanced breast cancer and started chemotherapy; at this point her depressive and cognitive symptoms became more pronounced. We conclude that it will take two-to-three years of follow-up to determine whether the cognitive symptoms are residual to her depression or a newly emerging dementia (or both). This case shows that for elderly patients who have symptoms of both depression and dementia, detailed clinical examination and neuropsychiatric testing may need to be combined with longitudinal assessment of their responsiveness to treatment before a definitive diagnosis can be assigned.

The Utilization of Retinal Nerve Fiber Layer Thickness to Predict Cognitive Deterioration.

Our previous studies have shown that longitudinal reduction in retinal nerve fiber layer (RNFL) thickness is associated with cognitive deterioration. However, whether the combination of longitudinal reduction in RNFL thickness with baseline episodic memory performance can better predict cognitive deterioration remains unknown. Therefore, we set out to re-analyze the data obtained from our previous studies with 78 elderly adults (mean age 74.4 ± 3.83 years, 48.7% male) in the community over a 25-month period. The participants were categorized as either stable participants whose cognitive status did not change (n = 60) or converted participants whose cognitive status deteriorated (n = 18). A logistic regression analysis was applied to determine a conversion score for predicting the cognitive deterioration in the participants. We found that the area under the receiver operating characteristic curve (AUC) for the multivariable model was 0.854 (95% CI 0.762-0.947) using baseline story recall as a predictor, but the AUC increased to 0.915 (95% CI 0.849-0.981) with the addition of the longitudinal reduction of RNFL thickness in the inferior quadrant. The conversion score was significantly higher for the converted participants than the stable participants (0.59 ± 0.30 versus 0.12 ± 0.19, p <  0.001). Finally, the optimal cutoff value of the conversion score (0.134) was determined by the analysis of receiver operating characteristic curve, and this conversion score generated a sensitivity of 0.944 and a specificity of 0.767 in predicting the cognitive deterioration. These findings have established a system to perform a larger scale study to further test whether the longitudinal reduction in RNFL thickness could serve as a biomarker of Alzheimer's disease.

Is the Best Evidence Good Enough: Quality Assessment and Factor Analysis of Meta-Analyses on Depression.

BACKGROUND: The quality of meta-analyses (MAs) on depression remains uninvestigated. OBJECTIVE: To assess the overall reporting and methodological qualities of MAs on depression and to explore potential factors influencing both qualities. METHODS: MAs investigating epidemiology and interventions for depression published in the most recent year (2014-2015) were selected from PubMed, EMBASE, PsycINFO and Cochrane Library. The characteristics of the included studies were collected and the total and per-item quality scores of the included studies were calculated based on the two checklists. Univariate and multivariate linear regression analyses were used to explore the potential factors influencing the quality of the articles. RESULTS: A total of 217 MAs from 74 peer-reviewed journals were included. The mean score of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was 23.0 of 27 and mean score of Assessment of Multiple Systematic Reviews (AMSTAR) was 8.3 of 11. Items assessing registration and protocol (14.2%, 37/217) in PRISMA and item requiring a full list of included and excluded studies (16.1%, 40/217) in AMSTAR had poorer adherences than other items. The MAs that included only RCTs, pre-registered, had five more authors or authors from Cochrane groups and the MAs found negative results had better reporting and methodological qualities. CONCLUSIONS: The reporting and methodological qualities of MAs on depression remained to be improved. Design of included studies, characteristics of authors and pre-registration in PROSPERO database are important factors influencing quality of MAs in the field of depression.

Meta-analysis of the relationship of peripheral retinal nerve fiber layer thickness to Alzheimer's disease and mild cognitive impairment.

BACKGROUND: Previous studies report that the thickness of the peripheral retinal nerve fiber layer (RNFL) in individuals with Alzheimer's disease (AD) and mild cognitive impairment (MCI) is significantly thinner than in normal controls (NC), but RNFL thickness in different quadrants of the optic nerve remains unclear. AIM: Conduct a systematic review of studies that assess peripheral RNFL thickness in AD and MCI. METHODS: Based on pre-defined criteria, studies in English or Chinese were identified from PubMed, Embase, ISI web of knowledge, Ovid/Medline, Science Direct, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Chongqing VIP database, WANFANG DATA, and the China BioMedical Literature Service System (SinoMed). Review Manager 5.3 was used for analysis. RESULTS: The 19 cross-sectional studies identified had a pooled sample of 1455 individuals. There was substantial heterogeneity between studies that compared RNFL in AD or MCI to normal controls, but this heterogeneity was primarily restricted to low-quality studies. Combining 6 high-quality studies (n=578) indicated that total RNFL thickness and the thickness of superior and inferior RNFL quadrants in AD were significantly thinner than in normal controls. Similarly, combining 5 high-quality studies (n=541) indicated significantly thinner total RNFL thickness in MCI than in controls. Six studies (n=589) found thinner RNFL in the superior and inferior quadrants in MCI than in controls;and 6 studies (n=487) found thinner RNFL in the temporal quadrant in MCI than in controls. Finally, 7 studies (n=432) indicated that total RNFL was thinner in AD than in MCI, and 6 studies (n=364) indicated thinner RNFL in the superior and inferior quadrants in AD than in MCI. CONCLUSION: Much of the heterogeneity in results from previous studies may be due to poor methodology. Peripheral RNFL thicknesses, particularly in the superior and inferior quadrants, becomes progressively thinner as cognitive function declines, so this could be a candidate biomarker for early identification of AD. Methodologically rigorous studies in large population-based cohort studies that follow elderly individuals over time and that simultaneously collect information on potential mediating factors (such as blood pressure, blood glucose, and lipid levels) are needed to confirm or disprove the potential predictive value of RNFL.

Different MMSE Score Is Associated with Postoperative Delirium in Young-Old and Old-Old Adults.

BACKGROUND: Postoperative delirium is one of the most common postoperative complications in geriatric patients. Mini-mental state examination (MMSE) assesses cognitive function in patients and is associated with postoperative delirium. However, whether there is an age-dependent relationship between preoperative MMSE score and postoperative delirium remains unknown. METHODS: We therefore set out to investigate the association between preoperative MMSE score and postoperative delirium in young-old (≤80 year-old, 75.46±4.69 years, 27.0% male, n = 63) and old-old (>80 year-old, 84.51±3.46 years, 20.9% male, n = 67) participants, who had repairs of hip fractures under general anesthesia. The Confusion Assessment Method and Memorial Delirium Assessment Scale were administrated before surgery, and on the first, second and fourth days after surgery, to assess the incidence and severity of the delirium, respectively. A receiver operating characteristic curve analysis was used to calculate the optimal cutoff score of MMSE in predicting postoperative delirium. RESULTS: Thirty-four (26.2%) of 130 patients (80.12±6.12 years, 23.8% male) developed postoperative delirium. Preoperative MMSE scores were negatively associated with higher incidences and greater severity of postoperative delirium. The optimal cutoff scores of MMSE associated with postoperative delirium for young-old and old-old participants were 18.4 and 21.4, with a sensitivity of 60% and 83.8%, and a specificity of 92.5% and 62.8%, respectively. CONCLUSION: The data demonstrated the optimal cutoff score of MMSE associated with postoperative delirium in young-old adults might be lower than that in old-old adults. Pending further investigation, these findings suggest that the association between preoperative MMSE score and postoperative delirium is age-dependent.

Retinal nerve fiber layer thickness is associated with episodic memory deficit in mild cognitive impairment patients.

Changes in retinal nerve fiber layer (RNFL) thickness have been reported in patients with mild cognitive impairment (MCI), the pre-dementia stage of Alzheimer's disease (AD). However, whether RNFL thickness is associated with specific cognitive impairment of MCI patients remains unknown. Therefore, we set out to investigate the potential association between RNFL thickness and episodic memory in MCI patients. Seventy five older adults (mean age 74 ± 3 years, 55% men) were included in the study. Fifty-two participants had normal cognition (NC), and 23 participants were diagnosed with MCI. RNFL thickness was obtained by optical coherence tomography measurement. Cognitive function was evaluated by the Repeatable Battery for the Assessment of Neuropsychological Status on the same day of the optical examination. We found that nasal quadrant RNFL thickness was positively associated with episodic memory scores in the participants with normal cognition: word list learning (r=0.392, p=0.004) and story recall (r=0.307, p=0.027). In the participants with MCI, however, the inferior quadrant RNFL thickness was inversely associated with the episodic memory score: word list learning (r=-0.652, p=0.001), story memory (r=-0.429, p=0.041), and story recall (r=-0.502, p=0.015,). The findings from this pilot study suggest that the inferior quadrant RNFL thickness was associated with specific episodic memory in MCI patients and could serve as a biomarker of MCI and AD. These findings would promote more studies to determine the potential application of RNFL as an AD biomarker.

Greater attenuation of retinal nerve fiber layer thickness in Alzheimer's disease patients.

Thinning of retinal nerve fiber layer (RNFL) may reflect neurodegeneration of the central nervous system, which has been reported as part of the neuropathogenesis of Alzheimer's disease (AD). Specifically, AD patients have thinner RNFL as compared to age-matched normal controls. However, whether reduction of RNFL over time can predict those at higher risk to develop cognitive deterioration remains unknown. We therefore set out a prospective clinical investigation to determine both the reduction of RNFL thickness and the deterioration of cognitive function over a period of 25 months in 78 participants (mean age 72.31 ± 3.98 years, 52% men). The participants were categorized as stable participants whose cognitive status remained unchanged (n = 60) and converted participants whose cognitive status deteriorated, which was diagnosed by DSM-VI (for AD) and Petersen's definition (for mild cognitive impairment) (n = 18). Here we show for the first time that the converted participants had greater reduction of RNFL thickness than the stable participants. Specifically, the reduction in the thickness of the inferior quadrant RNFL in the converted participants was greater than that in stable participants [-11.0 ± 12.8 (mean ± standard deviation) µm versus 0.4 ± 15.7 µm, p = 0.009]. These data showed that greater reduction in the inferior quadrant of RNFL thickness might indicate a higher risk for the old adults to develop cognitive deterioration. These findings have established a system to embark on a larger scale study to further test whether changes in RNFL thickness can serve as a biomarker of AD.

Using the Chinese version of Memorial Delirium Assessment Scale to describe postoperative delirium after hip surgery.

OBJECTIVE: Memorial Delirium Assessment Scale (MDAS) assesses severity of delirium. However, whether the MDAS can be used in a Chinese population is unknown. Moreover, the optimal postoperative MDAS cutoff point for describing postoperative delirium in Chinese remains largely to be determined. We therefore performed a pilot study to validate MDAS in the Chinese language and to determine the optimal postoperative MDAS cutoff point for delirium. METHODS: Eighty-two patients (80 ± 6 years, 21.9% male), who had hip surgery under general anesthesia, were enrolled. The Confusion Assessment Method (CAM) and Mini-Mental State Examination (MMSE) were administered to the patients before surgery. The CAM and MDAS were performed on the patients on the first, second and fourth postoperative days. The reliability and validity of the MDAS were determined. A receiver operating characteristic (ROC) curve was used to determine the optimal Chinese version MDAS cutoff point for the identification of delirium. RESULTS: The Chinese version of the MDAS had satisfactory internal consistency (α = 0.910). ROC analysis obtained an average optimal MDAS cutoff point of 7.5 in describing the CAM-defined postoperative delirium, with an area under the ROC of 0.990 (95% CI 0.977-1.000, P < 0.001). CONCLUSIONS: The Chinese version of the MDAS had good reliability and validity. The patients whose postoperative Chinese version MDAS cutoff point score was 7.5 would likely have postoperative delirium. These results have established a system for a larger scale study in the future.

The attenuation of retinal nerve fiber layer thickness and cognitive deterioration.

Thinner retinal nerve fiber layer (RNFL) has been reported in Alzheimer's disease (AD) patient. However, whether changes in RNFL thickness can predict the cognitive deterioration remains unknown. We therefore set out a prospective clinical investigation to determine the potential association between the attenuation of RNFL thickness and the deterioration of cognitive function over a period of 25 months. We assessed cognitive function using the Repeatable Battery for the Assessment of Neuropsychological Status and measured RNFL thickness employing optical coherence tomography in 78 participants (mean age 72.31 ± 3.98 years, 52% men). The participants were categorized as stable participants whose cognitive status remained no change (N = 60) and converted participants whose cognitive status deteriorated (N = 18). We found that there was an association between the attenuation of superior quadrant RNFL thickness and the deterioration of cognitive function in the stable participants. In the converted participants, however, there was an inverse association between the reduction of inferior quadrant RNFL thickness and decline of cognitive functions [scores of list recall (R = -0.670, P = 0.002), adjusted (R = -0.493, P = 0.031)]. These data showed that less reduction in the inferior quadrant of RNFL thickness might indicate a higher risk for the patients to develop cognitive deterioration. These findings have established a system to embark a larger scale study to further test whether changes in RNFL thickness can serve as a biomarker of AD, and would lead to mechanistic studies to determine the cellular mechanisms of cognitive deterioration.