Deconstructing pathological tau by biological process in early stages of Alzheimer disease: a method for quantifying tau spatial spread in neuroimaging

BACKGROUND

Neuroimaging studies often quantify tau burden in standardized brain regions to assess Alzheimer disease (AD) progression. However, this method ignores another key biological process in which tau spreads to additional brain regions. We have developed a metric for calculating the extent tau pathology has spread throughout the brain and evaluate the relationship between this metric and tau burden across early stages of AD.

METHODS

445 cross-sectional participants (aged ≥ 50) who had MRI, amyloid PET, tau PET, and clinical testing were separated into disease-stage groups based on amyloid positivity and cognitive status (older cognitively normal control, preclinical AD, and symptomatic AD). Tau burden and tau spatial spread were calculated for all participants.

FINDINGS

We found both tau metrics significantly elevated across increasing disease stages (p < 0.0001) and as a function of increasing amyloid burden for participants with preclinical (p < 0.0001, p = 0.0056) and symptomatic (p = 0.010, p = 0.0021) AD. An interaction was found between tau burden and tau spatial spread when predicting amyloid burden (p = 0.00013). Analyses of slope between tau metrics demonstrated more spread than burden in preclinical AD (β = 0.59), but then tau burden elevated relative to spread (β = 0.42) once participants had symptomatic AD, when the tau metrics became highly correlated (R = 0.83).

INTERPRETATION

Tau burden and tau spatial spread are both strong biomarkers for early AD but provide unique information, particularly at the preclinical stage. Tau spatial spread may demonstrate earlier changes than tau burden which could have broad impact in clinical trial design.

FUNDING

This research was supported by the Knight Alzheimer Disease Research Center (Knight ADRC, NIH grants P30AG066444, P01AG026276, P01AG003991), Dominantly Inherited Alzheimer Network (DIAN, NIH grants U01AG042791, U19AG03243808, R01AG052550-01A1, R01AG05255003), and the Barnes-Jewish Hospital Foundation Willman Scholar Fund.

Parsing memory and nonmemory contributions to age-related declines in mnemonic discrimination performance: a hierarchical Bayesian diffusion decision modeling approach

The mnemonic discrimination task (MDT) is a widely used cognitive assessment tool. Performance in this task is believed to indicate an age-related deficit in episodic memory stemming from a decreased ability to pattern-separate among similar experiences. However, cognitive processes other than memory ability might impact task performance. In this study, we investigated whether nonmnemonic decision-making processes contribute to the age-related deficit in the MDT. We applied a hierarchical Bayesian version of the Ratcliff diffusion model to the MDT performance of 26 younger and 31 cognitively normal older adults. It allowed us to decompose decision behavior in the MDT into different underlying cognitive processes, represented by specific model parameters. Model parameters were compared between groups, and differences were evaluated using the Bayes factor. Our results suggest that the age-related decline in MDT performance indicates a predominantly mnemonic deficit rather than differences in nonmnemonic decision-making processes. In addition, this mnemonic deficit might also involve a slowing in processes related to encoding and retrieval strategies, which are relevant for successful memory as well. These findings help to better understand what cognitive processes contribute to the age-related decline in MDT performance and may help to improve the diagnostic value of this popular task.

Effect of Periodontal Treatment on HbA1c among Patients with Prediabetes

Evidence is limited regarding whether periodontal treatment improves hemoglobin A1c (HbA1c) among people with prediabetes and periodontal disease, and it is unknown whether improvement of metabolic status persists >3 mo. In an exploratory post hoc analysis of the multicenter randomized controlled trial “Antibiotika und Parodontitis” (Antibiotics and Periodontitis)—a prospective, stratified, double-blind study—we assessed whether nonsurgical periodontal treatment with or without an adjunctive systemic antibiotic treatment affects HbA1c and high-sensitivity C-reactive protein (hsCRP) levels among periodontitis patients with normal HbA1c (≤5.7%, n = 218), prediabetes (5.7% < HbA1c < 6.5%, n = 101), or unknown diabetes (HbA1c ≥ 6.5%, n = 8) over a period of 27.5 mo. Nonsurgical periodontal treatment reduced mean pocket probing depth by >1 mm in both groups. In the normal HbA1c group, HbA1c values remained unchanged at 5.0% (95% CI, 4.9% to 6.1%) during the observation period. Among periodontitis patients with prediabetes, HbA1c decreased from 5.9% (95% CI, 5.9% to 6.0%) to 5.4% (95% CI, 5.3% to 5.5%) at 15.5 mo and increased to 5.6% (95% CI, 5.4% to 5.7%) after 27.5 mo. At 27.5 mo, 46% of periodontitis patients with prediabetes had normal HbA1c levels, whereas 47.9% remained unchanged and 6.3% progressed to diabetes. Median hsCRP values were reduced in the normal HbA1c and prediabetes groups from 1.2 and 1.4 mg/L to 0.7 and 0.7 mg/L, respectively. Nonsurgical periodontal treatment may improve blood glucose values among periodontitis patients with prediabetes (ClinicalTrials.gov NCT00707369).

The narcissistic self and its psychological and neural correlates: an exploratory fMRI study

BACKGROUND

The concept of narcissism has been much researched in psychoanalysis and especially in self psychology. One of the hallmarks of narcissism is altered emotion, including decreased affective resonance (e.g. empathy) with others, the neural underpinnings of which remain unclear. The aim of our exploratory study was to investigate the psychological and neural correlates of empathy in two groups of healthy subjects with high and low narcissistic personality trait. We hypothesized that high narcissistic subjects would show a differential activity pattern in regions such as the anterior insula that are typically associated with empathy.

METHOD

A sample of 34 non-clinical subjects was divided into high (n=11) and low (n=11) narcissistic groups according to the 66th and 33rd percentiles of their scores on the Narcissism Inventory (NI). Combining the psychological, behavioral and neuronal [i.e. functional magnetic resonance imaging (fMRI)] measurements of empathy, we compared the high and low narcissistic groups of subjects.

RESULTS

High narcissistic subjects showed higher scores on the Symptom Checklist-90 - Revised (SCL-90-R) and the 20-item Toronto Alexithymia Scale (TAS-20) when compared to low narcissistic subjects. High narcissistic subjects also showed significantly decreased deactivation during empathy, especially in the right anterior insula.

CONCLUSIONS

Psychological and neuroimaging data indicate respectively higher degrees of alexithymia and lower deactivation during empathy in the insula in high narcissistic subjects. Taken together, our preliminary findings demonstrate, for the first time, psychological and neuronal correlates of narcissism in non-clinical subjects. This might stipulate both novel psychodynamic conceptualization and future psychological-neuronal investigation of narcissism.

Determinants of health-related quality of life in coronary artery disease patients: a prospective study generating a structural equation model

The authors used structural equation modeling to test a conceptual model of HRQL in coronary artery disease. The model, which included biomedical factors and individual and environmental characteristics, was tested in a multicenter group of 465 patients at three timepoints (baseline evaluation of chest pain and 1- and 3-month follow-ups). A satisfactory fit was obtained for the model over time. Depression and anxiety symptoms exerted the most significant influence on HRQL. HRQL and the mediating factors were found to be distinct phenomena. The authors concluded that mediating factors, especially depression and anxiety symptoms, should be taken into consideration in clinical routine if HRQL is regarded as a clinical outcome.

[Videotape preparation of patients before hip replacement surgery improves mobility after three months]

Long-term follow-up investigations of the effect of psychological preparation on postoperative physical outcome measures have very rarely been done. In this study a three-month follow-up of a previous investigation of videotape preparation before hip replacement surgery is reported. 100 patients who previously participated in a randomized controlled study received physical examination and x-ray of the hip joint three months after the operation. The mobility of the replaced hip joint was recorded as well as ossifications of the joint. Prepared patients showed a significantly higher improvement of internal rotation, rotational range of motion, and abduction, compared to the controls. The effect sizes ranged between 21% and 32% and, thus, were of clinical relevance. Prepared patients showed less ossifications (15%) that controls (22%), this difference was not significant. For the first time it could be demonstrated that psychological preparation before surgery can not only improve short-term and psychosocial outcome parameters, but also long-term physical measures. The reason for this effect remains to be investigated.

[Cortisol in night-urine: Introduction of a research method in psychoneuroendocrinology]

Cortisol is one of the major parameters investigated in psychoneuroendocrinological research, but the methods employed for sample collecting are often unsatisfactory. A suitable method of sample collection should allow for the integrative assessment of long-term changes of the HPA-system, should be non-invasive, and should not exceed the subject's compliance. The assessment of cortisol in night-urine fulfils these demands; although this method has been occasionally employed, it has not yet been described systematically. For the first time a detailed description is given here that allows for a standardized replication. In ten previous studies and three investigations of our own this method has been successfully applied to detect changes in the cortisol excretion of patients with endocrinological and psychiatric disorders as well as in subjects under conditions of psychosocial stress. The determination of cortisol in night-urine represents an ideal method for the assessment of changes in the basal HPA-activity in numerous areas of psychoneuroendocrinological research, e.g. field and screening studies in natural environment, clinical studies in psychiatry and especially follow-up studies in psychotherapy research.

[Patients' need for information before surgery]

Frequently, prior to surgery, patients are provided with information in order to meet legal and hospital requirements, but without taking their psychological needs into consideration. In order to learn how to improve this situation, the present study was performed. By means of a semi-structured interview including a newly constructed card system, that avoids giving patients undemanded and possibly harmful implicit information, the need for information of 60 patients before hip- or knee-replacement surgery were investigated in great detail. The results show that 83.3% of the patients want to be prepared by the surgeon, preferably by means of an oral communication (75.0%). Most frequently the day when decision for surgery is made and the day of hospitalization were preferred as point of time for preparation (30% each). Patients were more interested in information about the operation and recovery (43.3% each) than about risks (33.3%). Only 11.7% wanted to get psychological preparation prior to surgery. We conclude that coming into contact and establishing a trustful relationship with the surgeon who does the operation is the most crucial need of surgical patients. He should give presurgical information according to the patient's needs, which often do not focus on the risks, as legal regulations do. By providing psychological preparation for the small number of patients in need, psychological specialists may contribute to improve satisfaction and outcome of surgical patients.

Gabapentin-induced mood changes with hypomanic features in adults

We report two adults who received gabapentin (GBP) and subsequently developed behavioural side effects. Indications for GBP treatment were newly diagnosed epilepsy in one and painful paraesthesiae in the other. Both had no past history of psychiatric or behavioural disorder. Abnormal behaviour consisted of elevated mood, euphoria, and increased energy in both patients, and pressure of speech and decreased need for sleep in one of them. These symptoms were transient and fully reversible. One patient had to discontinue GBP. Behavioural changes were not related to seizure activity. They should be recognized as a possible side effect of GBP treatment in adults.

Videotape preparation of patients before hip replacement surgery reduces stress

OBJECTIVE

Elective surgery represents a considerable source of stress for the patient. Many attempts have been made to prepare patients before surgery with the aim of reducing stress and improving outcome. This study used a novel approach to fulfill this aim by showing a videotape of a patient undergoing total hip replacement surgery, covering the time period from hospital admission to discharge, that strictly keeps to the patient's perspective.

METHODS

Before elective total hip replacement surgery, 100 patients were randomly assigned to a control group or a preparation group; the latter group was shown the videotape on the evening before surgery. Anxiety and pain were evaluated daily for 5 days, beginning with the preoperative day, by means of the State-Trait Anxiety Inventory and a visual analog scale. Intraoperative heart rate and blood pressure, as well as postoperative intake of analgesics and sedatives, were recorded. Urinary levels of cortisol, epinephrine, and norepinephrine were determined in 12-hour samples collected at night for 5 nights, beginning with the preoperative night.

RESULTS

Compared with the control group, the preparation group showed significantly less anxiety on the morning before surgery and the mornings of the first 2 postoperative days, and significantly fewer of them had an intraoperative systolic blood pressure increase of more than 15%. The pain ratings did not differ significantly between the two groups, but the prepared patients needed less analgesic medication after surgery. Prepared patients had significantly lower cortisol excretion during the preoperative night and the first 2 postoperative nights. Excretion of catecholamines did not differ significantly between groups.

CONCLUSIONS

We conclude that use of the videotape decreased anxiety and stress, measured in terms of urinary cortisol excretion and intraoperative systolic blood pressure increase, in patients undergoing hip replacement surgery and prepared them to cope better with postoperative pain.

The stress-reaction process and the adaptive modification and reorganization of neuronal networks

On the basis of a comprehensive definition of the stress-reaction process (SRP), the neurobiological and psychological consequences of this process, which are elicited by either controllable or uncontrollable stress, are described. We conclude that controllable stress triggers the stabilization and facilitation of neuronal networks involved in the generation of appropriate patterns of appraisal and coping, whereas uncontrollable stress favors the extinction of inappropriate patterns and the reorganization of neuronal connections underlying certain inappropriate behaviors. Both controllable and uncontrollable stress-reaction processes are therefore inherent challenges to the development and essential prerequisites of the adaptation of an individual's behavior to the demands of the ever-changing external world. The overabundance, as well as the lack, of either kind of SRP may lead to different psychodevelopmental failures and psychiatric disturbances.

Predictors of relapse and rehospitalization in schizophrenia and schizoaffective disorder

In a German multicenter treatment study, 354 patients with schizophrenia and schizoaffective disorder were followed for 2 years. The data collected were taken as a basis for the present predictor study. For the first time, the technique of classification and regression tree (CART) analysis has been employed for this purpose. CART yielded informative data and appeared to be a useful instrument in predictor research. On the outcome variables "relapse" and "rehospitalization," significant predictor variables were found in several areas: neuroleptic treatment, onset and previous course (precipitating factors, first manifestation, hospitalization in the preceding year, suicide attempts), psychopathology (residual type, schizoaffective disorder), social adjustment (marital status, employment, intensity of life, Phillips score), previous life experiences (traumatic experiences and psychiatric or developmental disturbances in childhood), and biology (gender, age). Our investigation confirmed the generally prevalent views regarding the value of neuroleptic treatment, the multifactorial etiology, and the vulnerability stress model of schizophrenia.

[A psychological therapy methods in chronic non-radicular backache]

The presence of psychological co-morbidity and difficulties in coping with chronic low-back pain are indications for the application of psychological therapy procedures. In the treatment of patients with chronic pain, the aim of therapy as well as the technique of the traditionally employed psychotherapeutic procedures need to be modified. What is of immediate importance is to promote an active pattern of coping with pain and discourage pain-related inactivity and reduce feelings of helplessness and hopelessness. To achieve this, it is necessary to combine various psychological treatment modalities (relaxation techniques and behavioural or psychodynamic therapy) with exercise programs as in physiotherapy or sports medicine. In the choice of the appropriate psychotherapeutic modalities, it is important to take into consideration the extent of chronicity of pain, the patient's subjective understanding of the illness, a possible wish of the patient for early retirement, previous experience with chronic pain and the extent to which the patient has been psychologically traumatised (especially in his childhood and youth). Relatives should be integrated in the planning and possibly also in carrying out of the treatment. Symptom-specific group therapy might motivate patients to undergo treatment and to change their habitual ways of life. A multimodal treatment approach incorporating orthopaedic, sports medicine, physiotherapeutic, psychological and socio-therapeutic procedures have proved to be more effective in the treatment of chronic pain than one employing monocausal treatment modalities.

[Psychosomatic aspects of chronic pain]

This paper gives a report on the current views of psychosomatic theories on chronic pain. Based on Melzack's and Wall's "gate-control theory", Freud's ideas on hysteric neurosis, and Engel's "pain-prone patient" the unidirectional nociceptive model of pain is replaced by a cybernetic system of biopsycho-social etiology. The psychodynamic theories of pain-proneness, the narcissistic mechanism in the etiology of pain, the mechanism of conversion, states of psychovegetative tension and processes of learning are presented. In addition the impact of gain from illness, life-events, coping, the doctors behavior and the comorbidity of affective disorders on pain syndromes becoming chronic is pointed out. As an example the multifactorial etiology of chronic low back pain is demonstrated.

[Coping with illness in myasthenia gravis]

Within the past few years, the introduction of immunosuppressants in the treatment of myasthenia gravis, has turned this severe, chronic and life-threatening disease into a moderate illness with good chances of control or even remission. Of 44 patients whose coping behavior and course of disease we investigated, only seven experienced a significant change in severity of the disease within nine months. This consistency in the course of the disease was also reflected in the forms of coping with the disease: in contrast to the situation two decades ago, today's myasthenia gravis patients are no longer caught up in the dilemma between passive dependency and active resistance, most of them adopting an attitude of calm acceptance. According to the Berne Forms of Coping (BEFO) which we applied, this attitude is expressed as a pattern of passive cooperation, acceptance, distraction and relativization. This coping pattern remained largely intact even in relation to the severity of the disease and the retrospectively assessed course of the disease. We present two cases to illustrate the influence of coping behavior on the course of the disease. Comparison with two other patient groups (rheumatoid arthritis and hip osteo-arthrosis) showed that there is no disease specificity of coping behavior. It can be assumed that there is a basic pattern in coping with chronic diseases, the manifestation of which is dependent on the severity and prognosis of the disease. If depressive reactions to the disease are excluded, the prevalence of longer-term pre-existent psychiatric disorders among MG patients corresponds to the average for the general population, although there is a relatively high incidence of anxiety disorders.(ABSTRACT TRUNCATED AT 250 WORDS)

Coping with myasthenia gravis and implications for psychotherapy

The aim of this study was to investigate psychosocial influences and mechanisms of coping to establish indications for psychotherapy in patients with myasthenia gravis. We investigated clinical symptoms, personality, psychopathology, and coping in 44 patients with myasthenia gravis. The patients' personalities were not characteristically altered, and in 29.5% (13/44) of them, preexistent, long-term psychiatric disturbances (according to International Classification of Diseases criteria) were present, which corresponds to the prevalence in the average population. In general, coping was characterized by an attitude of calmness and acceptance, which is attributable to effective medical treatment and could be considered an unspecific mode of coping with chronic diseases of moderate severity. Four women had undergone psychotherapy because of neurotic symptoms that were unrelated to myasthenia gravis. At the end of psychotherapy, their myasthenic symptoms had greatly improved or disappeared. Psychotherapeutic techniques may be helpful in patients with neurotic or reactive psychiatric symptoms, but there is no general implication for psychotherapy in myasthenic patients, especially if there is adequate "somatic" therapy.