Life-Course Brain Health as a Determinant of Late-Life Mental Health: American Association for Geriatric Psychiatry Expert Panel Recommendations

This position statement of the Expert Panel on Brain Health of the American Association for Geriatric Psychiatry (AAGP) emphasizes the critical role of life course brain health in shaping mental well-being during the later stages of life. Evidence posits that maintaining optimal brain health earlier in life is crucial for preventing and managing brain aging-related disorders such as dementia/cognitive decline, depression, stroke, and anxiety. We advocate for a holistic approach that integrates medical, psychological, and social frameworks with culturally tailored interventions across the lifespan to promote brain health and overall mental well-being in aging adults across all communities. Furthermore, our statement underscores the significance of prevention, early detection, and intervention in identifying cognitive decline, mood changes, and related mental illness. Action should also be taken to understand and address the needs of communities that traditionally have unequal access to preventive health information and services. By implementing culturally relevant and tailored evidence-based practices and advancing research in geriatric psychiatry, behavioral neurology, and geroscience, we can enhance the quality of life for older adults facing the unique challenges of aging. This position statement emphasizes the intrinsic link between brain health and mental health in aging, urging healthcare professionals, policymakers, and a broader society to prioritize comprehensive strategies that safeguard and promote brain health from birth through later years across all communities. The AAGP Expert Panel has the goal of launching further activities in the coming months and years.

Field Testing of Ro-Tri, a Robot-Mediated Triadic Interaction for Older Adults

Older adults residing in long term care (LTC) settings commonly experience apathy, a neuropsychiatric condition with adverse consequences of increased morbidity and mortality. Activities that combine social, physical and cognitive stimuli are most effective in engaging older adults with apathy but are time consuming and require significant staff resources. We present the results from an initial pilot field study of our socially assistive robotic (SAR) system, Ro-Tri, capable of multi-modal interventions to foster social interaction between pairs of older adults. Seven paired participants attended two sessions a week for three weeks. Sessions consisted of robot-mediated triadic interactions with three types of activities repeated once over the 3 weeks. Ro-Tri gathered quantitative interaction data, head pose, vocal sound, and physiological signals to automatically evaluate older adults' activity and social engagement. Ro-Tri functioned smoothly without any technical issues. Older adults had > 90% attendance and 100% completion rate and remained engaged with the system throughout the study duration. Participants' visual attention toward the SAR system and their partners increased 7.2% and 4.7%, respectively, with their interaction effort showing an increase of 2.9%. Older adults and LTC staff had positive perceptions with the system. These initial results demonstrate Ro-Tri's ability to engage older adults, encourage social human-to-human interaction, and assess the changes using quantitative metrics. Future studies will determine SAR's impact on apathy in LTC older adults.

Can Robots Encourage Social Engagement Among Older Adults?

Apathy in older adults in long term care (LTC) settings is common, associated with morbidity and mortality, and requires extensive personnel time. Most LTC sites are limited in their ability to provide activities. We conducted a 3-month pilot study at two LTCs to determine whether a robot, with/without virtual reality (VR), was successful in encouraging social engagement between older LTC adults. Three robot activities were offered twice weekly for three weeks (6 sessions). Two activities with VR consisted of two book sorting games. One activity was “Simon Says” where older adults took turns as leaders. Demographics and cognitive data were collected. Videos were coded and analyzed using Noldus Observer: activity engagement as visual and verbal attention to the robot activity and social engagement as visual and verbal attention towards their partner. Participants were 2 men and 14 women, mean age 83. One dropped out because of hearing problems; one dropped out because of cognitive impairment. Fourteen, ie 7 pairs, attended all 6 sessions; ten had MCI and one had AD. Social and activity engagement varied by activity and by participant. Participants’ perceptions (7-point Likert scale) remained positive over time (6.33 (SD 0.94) to 6.52 (SD 0.61)) but decreased slightly for the repeat activities (6.19 (SD 1.01) to 5.96 (SD 1.13)). Robots hold promise in LTC as ways to engage older adults who suffer from apathy. Further work is necessary to elucidate participant- and activity-level characteristics most conducive for success and mechanisms to increase the number and variety of activities.

Estradiol administration differentially affects the response to experimental psychosocial stress in post-menopausal women with or without a history of major depression

BACKGROUND:

The effects of estradiol on the brain regions involved in the response to stress and emotional processes may be particularly important in women who have alterations in these systems that make them vulnerable to Major Depressive Disorder (MDD). This study examined whether the effect of estradiol administration on the subjective distress and mood response to a laboratory-based psychosocial stress task differs in women with and without a history of MDD.

METHODS:

Participants were 65 euthymic postmenopausal women, with and without a history of MDD. They received either 3 months of open-label oral estradiol or did not receive estradiol. After 3 months, participants completed the Montreal Stress Imaging Task (MIST) and subjective distress and mood ratings.

RESULTS:

The effect of estradiol on subjective distress following the MIST differed based on MDD history. In women without a history of MDD, estradiol administration was associated with greater subjective distress than no estradiol. However, in women with a history of MDD, estradiol administration was associated with less subjective distress compared to no estradiol.

LIMITATIONS:

This study included open-label administration of estradiol and participants were not blinded to administration. Interpretation of result should include consideration of the relatively small group sizes and that results may not generalize to currently depressed individuals.

CONCLUSIONS:

In euthymic women with a history of MDD, estradiol may benefit the affective response to psychosocial stress while having comparatively little benefit in women with no MDD history. Further work should explore whether estradiol administration reduces the risk of depression recurrence in post-menopausal women with past MDD.

Reducing Antipsychotic Medication Use in Nursing Homes: A Qualitative Study of Nursing Staff Perceptions

Background and Objectives

The purpose of this study was to use qualitative methods to explore nursing home staff perceptions of antipsychotic medication use and identify both benefits and barriers to reducing inappropriate use from their perspective.

Research Design and Methods

Focus groups were conducted with a total of 29 staff in three community nursing homes that served both short and long-stay resident populations.

Results

The majority (69%) of the staff participants were licensed nurses. Participants expressed many potential benefits of antipsychotic medication reduction with four primary themes: (a) Improvement in quality of life, (b) Improvement in family satisfaction, (c) Reduction in falls, and (d) Improvement in the facility Quality Indicator score (regulatory compliance). Participants also highlighted important barriers they face when attempting to reduce or withdraw antipsychotic medications including: (a) Family resistance, (b) Potential for worsening or return of symptoms or behaviors, (c) Lack of effectiveness and/or lack of staff resources to consistently implement nonpharmacological management strategies, and (d) Risk aversion of staff and environmental safety concerns.

Discussion and Implications

Nursing home staff recognize the value of reducing antipsychotic medications; however, they also experience multiple barriers to reduction in routine clinical practice. Achievement of further reductions in antipsychotic medication use will require significant additional efforts and adequate clinical personnel to address these barriers.

Glutamate-sensitive imaging and evaluation of cognitive impairment in multiple sclerosis

BACKGROUND

Cognitive impairment (CI) profoundly impacts quality of life for patients with multiple sclerosis (MS). Dysfunctional regulation of glutamate in gray matter (GM) has been implicated in the pathogenesis of MS by post-mortem pathological studies and in CI by in vivo magnetic resonance spectroscopy, yet GM pathology is subtle and difficult to detect using conventional T₁- and T₂-weighted magnetic resonance imaging (MRI). There is a need for high-resolution, clinically accessible imaging techniques that probe molecular changes in GM.

OBJECTIVE

To study cortical GM pathology related to CI in MS using glutamate-sensitive chemical exchange saturation transfer (GluCEST) MRI at 7.0 Tesla (7T).

METHODS

A total of 20 patients with relapsing-remitting MS and 20 healthy controls underwent cognitive testing, anatomical imaging, and GluCEST imaging. Glutamate-sensitive image contrast was quantified for cortical GM, compared between cohorts, and correlated with clinical measures of CI.

RESULTS AND CONCLUSION

Glutamate-sensitive contrast was significantly increased in the prefrontal cortex of MS patients with accumulated disability (p < 0.05). In addition, glutamate-sensitive contrast in the prefrontal cortex was significantly correlated with symbol digit modality test (r_S = -0.814) and choice reaction time (r_S = 0.772) scores in patients (p < 0.05), suggesting that GluCEST MRI may have utility as a marker for GM pathology and CI.

Transdermal Nicotine for the Treatment of Mood and Cognitive Symptoms in Nonsmokers With Late-Life Depression

OBJECTIVE

Late-life depression (LLD) is characterized by poor antidepressant response and cognitive dysfunction. This study examined whether transdermal nicotine benefits mood symptoms and cognitive performance in LLD.

METHODS

In a 12-week open-label outpatient study conducted between November 2016 and August 2017, transdermal nicotine was given to 15 nonsmoking older adults (≥ 60 years of age). Eligible participants met DSM-IV-TR criteria for major depressive disorder with ≥ 15 on the Montgomery-Asberg Depression Rating scale (MADRS) and endorsed subjective cognitive impairment. Transdermal nicotine patches were applied daily and titrated in a rigid dose escalation strategy to a maximum dose of 21.0 mg/d, allowing dose reductions for tolerability. The primary mood outcome was MADRS change measured every 3 weeks, with response defined as ≥ 50% improvement from baseline and remission as MADRS score ≤ 8. The primary cognitive outcome was the Conners Continuous Performance Test (CPT), a test of attention.

RESULTS

Robust rates of response (86.7%; 13/15 subjects) and remission (53.3%; 8/15 subjects) were observed. There was a significant decrease in MADRS scores over the study (β = -1.51, P < .001), with improvement seen as early as 3 weeks (Bonferroni-adjusted P value = .004). We also observed improvement in apathy and rumination. We did not observe improvement on the CPT but did observe improvement in subjective cognitive performance and signals of potential drug effects on secondary cognitive measures of working memory, episodic memory, and self-referential emotional processing. Overall, transdermal nicotine was well tolerated, although 6 participants could not reach the maximum targeted dose.

CONCLUSIONS

Nicotine may be a promising therapy for depressed mood and cognitive performance in LLD. A definitive placebo-controlled trial and establishment of longer-term safety are necessary before clinical usage.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02816138​.

Mechanisms of Cognitive Aging in the HIV-Positive Adult

PURPOSE OF REVIEW

As of the year 2016, an estimated 50% of the United States' HIV-Positive population is aged 50 years or older. Due to a combination of increased rates of infection in older adults, and successful anti-retroviral (ART) regimens allowing HIV-positive adults to survive for decades with the disease, we are now faced with a steadily graying HIV-positive population, with only limited knowledge of how the cognitive and physiological effects of aging intersect with those of chronic HIV-infection.

RECENT FINDINGS

Age-related changes to mood, cognition, and neurological health may be experienced differently in those living with HIV, and research concerning quality of life, mental health, and cognitive aging needs to account for and explore these factors more carefully in the coming years.

SUMMARY

This review will explore the topic of cognitive aging with HIV: 1. Central nervous system (CNS) infection of HIV and how the virus affects brain integrity and function; 2. Cognitive and behavioral symptoms of HIV-Associated Neurocognitive Disorders (HAND); 3. Neurobiological theories of Cognitive Aging and how these processes may be exacerbated by HIV-infection; 4: Clinical implications and complications of aging with HIV and factors that may result in poorer cognitive outcomes.

Estrogen enhances hippocampal gray-matter volume in young and older postmenopausal women: a prospective dose-response study

Estrogen administration following menopause has been shown to support hippocampally mediated cognitive processes. A number of previous studies have examined the effect of estrogen on hippocampal structure to determine the mechanism underlying estrogen effects on hippocampal function. However, these studies have been largely observational and provided inconsistent results. We examined the effect of short-term estradiol administration on hippocampal gray-matter volume in a prospective study with multiple doses of estradiol (placebo, 1 mg, and 2 mg). Following 3 months of estradiol administration, bilateral posterior hippocampal voxel-based gray-matter volume was increased in women who received 2-mg estradiol. There were no significant differences in total hippocampal volume and no significant effects on gray-matter volume in women who received placebo or 1-mg estradiol. These findings accord with previous animal studies and provide evidence of estrogen effects on hippocampal morphology that may represent a neurobiological mechanism for estrogen effects on cognition in postmenopausal women.

Subjective memory complaints are associated with poorer cognitive performance in adults with HIV

With successful antiretroviral therapy in the US, HIV-positive adults now routinely survive into old age. However, increased life expectancy with HIV introduces the added complication of age-related cognitive decline. Aging with HIV has been associated with poorer cognitive outcomes compared to HIV-negative adults. While up to 50% of older HIV-positive adults will develop some degree of cognitive impairment over their lifetime, cognitive symptoms are often not consistently monitored, until those symptoms are significant enough to impair daily life. In this study we found that subjective memory complaint (SMC) ratings correlated with measurable memory performance impairments in HIV-positive adults, but not HIV-negative adults. As the HIV-positive population ages, structured subjective cognitive assessment may be beneficial to identify the early signs of cognitive impairment, and subsequently allow for earlier interventions to maintain cognitive performance as these adults continue to survive into old age.

Contact heat sensitivity and reports of unpleasantness in communicative people with mild to moderate cognitive impairment in Alzheimer's disease: a cross-sectional study

BACKGROUND

Compared to healthy controls, people with Alzheimer's disease (AD) have been shown to receive less pain medication and report pain less frequently. It is unknown if these findings reflect less perceived pain in AD, an inability to recognize pain, or an inability to communicate pain.

METHODS

To further examine aspects of pain processing in AD, we conducted a cross-sectional study of sex-matched adults ≥65 years old with and without AD (AD: n = 40, female = 20, median age = 75; control: n = 40, female = 20, median age = 70) to compare the psychophysical response to contact-evoked perceptual heat thresholds of warmth, mild pain, and moderate pain, and self-reported unpleasantness for each percept.

RESULTS

When compared to controls, participants with AD required higher temperatures to report sensing warmth (Cohen's d = 0.64, p = 0.002), mild pain (Cohen's d = 0.51, p = 0.016), and moderate pain (Cohen's d = 0.45, p = 0.043). Conversely, there were no significant between-group differences in unpleasantness ratings (p > 0.05).

CONCLUSIONS

The between-group findings demonstrate that when compared to controls, people with AD are less sensitive to the detection of thermal pain but do not differ in affective response to the unpleasant aspects of thermal pain. These findings suggest that people with AD may experience greater levels of pain and potentially greater levels of tissue or organ damage prior to identifying and reporting injury. This finding may help to explain the decreased frequency of pain reports and consequently a lower administration of analgesics in AD.

Sex differences in psychophysical and neurophysiological responses to pain in older adults: a cross-sectional study

Background

Neuroimaging studies in younger adults have demonstrated sex differences in brain processing of painful experimental stimuli. Such differences may contribute to findings that women suffer disproportionately from pain. It is not known whether sex-related differences in pain processing extend to older adults.

Methods

This cross-sectional study investigated sex differences in pain reports and brain response to pain in 12 cognitively healthy older female adults and 12 cognitively healthy age-matched older male adults (age range 65–81, median = 67). Participants underwent psychophysical assessments of thermal pain responses, functional MRI, and psychosocial assessment.

Results

When compared to older males, older females reported experiencing mild and moderate pain at lower stimulus intensities (i.e., exhibited greater pain sensitivity; Cohen’s d = 0.92 and 0.99, respectively, p < 0.01) yet did not report greater pain-associated unpleasantness. Imaging results indicated that, despite the lower stimulus intensities required to elicit mild pain detection in females, they exhibited less deactivations than males in regions associated with the default mode network (DMN) and in regions associated with pain affect (bilateral dorsolateral prefrontal cortex, somatomotor area, rostral anterior cingulate cortex (rACC), and dorsal ACC). Conversely, at moderate pain detection levels, males exhibited greater activation than females in several ipsilateral regions typically associated with pain sensation (e.g., primary (SI) and secondary somatosensory cortices (SII) and posterior insula). Sex differences were found in the association of brain activation in the left rACC with pain unpleasantness. In the combined sample of males and females, brain activation in the right secondary somatosensory cortex was associated with pain unpleasantness.

Conclusions

Cognitively healthy older adults in the sixth and seventh decades of life exhibit similar sex differences in pain sensitivity compared to those reported in younger individuals. However, older females did not find pain to be more unpleasant. Notably, increased sensitivity to mild pain in older females was reflected via less brain deactivation in regions associated with both the DMN and in pain affect. Current findings elevate the rACC as a key region associated with sex differences in reports of pain unpleasantness and brain deactivation in older adults. Also, pain affect may be encoded in SII in both older males and females.

Electronic supplementary material

The online version of this article (doi:10.1186/s13293-015-0041-y) contains supplementary material, which is available to authorized users.

Estradiol levels modulate brain activity and negative responses to psychosocial stress across the menstrual cycle

Although ovarian hormones are thought to have a potential role in the well-known sex difference in mood and anxiety disorders, the mechanisms through which ovarian hormone changes contribute to stress regulation are not well understood. One mechanism by which ovarian hormones might impact mood regulation is by mediating the effect of psychosocial stress, which often precedes depressive episodes and may have mood consequences that are particularly relevant in women. In the current study, brain activity and mood response to psychosocial stress was examined in healthy, normally cycling women at either the high or low estradiol phase of the menstrual cycle. Twenty eight women were exposed to the Montreal Imaging Stress Task (MIST), with brain activity determined through functional magnetic resonance imaging, and behavioral response assessed with subjective mood and stress measures. Brain activity responses to psychosocial stress differed between women in the low versus high estrogen phase of the menstrual cycle: women with high estradiol levels showed significantly less deactivation in limbic regions during psychosocial stress compared to women with low estradiol levels. Additionally, women with higher estradiol levels also had less subjective distress in response to the MIST than women with lower estradiol levels. The results of this study suggest that, in normally cycling premenopausal women, high estradiol levels attenuate the brain activation changes and negative mood response to psychosocial stress. Normal ovarian hormone fluctuations may alter the impact of psychosocially stressful events by presenting periods of increased vulnerability to psychosocial stress during low estradiol phases of the menstrual cycle. This menstrual cycle-related fluctuation in stress vulnerability may be relevant to the greater risk for affective disorder or post-traumatic stress disorder in women.

Estrogen-cholinergic interactions: Implications for cognitive aging

This article is part of a Special Issue "Estradiol and Cognition". While many studies in humans have investigated the effects of estrogen and hormone therapy on cognition, potential neurobiological correlates of these effects have been less well studied. An important site of action for estrogen in the brain is the cholinergic system. Several decades of research support the critical role of CNS cholinergic systems in cognition in humans, particularly in learning and memory formation and attention. In humans, the cholinergic system has been implicated in many aspects of cognition including the partitioning of attentional resources, working memory, inhibition of irrelevant information, and improved performance on effort-demanding tasks. Studies support the hypothesis that estradiol helps to maintain aspects of attention and verbal and visual memory. Such cognitive domains are exactly those modulated by cholinergic systems and extensive basic and preclinical work over the past several decades has clearly shown that basal forebrain cholinergic systems are dependent on estradiol support for adequate functioning. This paper will review recent human studies from our laboratories and others that have extended preclinical research examining estrogen-cholinergic interactions to humans. Studies examined include estradiol and cholinergic antagonist reversal studies in normal older women, examinations of the neural representations of estrogen-cholinergic interactions using functional brain imaging, and studies of the ability of selective estrogen receptor modulators such as tamoxifen to interact with cholinergic-mediated cognitive performance. We also discuss the implications of these studies for the underlying hypotheses of cholinergic-estrogen interactions and cognitive aging, and indications for prophylactic and therapeutic potential that may exploit these effects.

Digitizing practical production work for high-stakes assessments / La numérisation de travaux pratiques de production pour les évaluations à enjeux élevés / La numérisation de travaux pratiques de production pour les évaluations à enjeux élevés

High-stakes external assessment for practical courses is fraught with problems impacting on the manageability, validity and reliability of scoring. Alternative approaches to assessment using digital technologies have the potential to address these problems. This paper describes a study that investigated the use of these technologies to create and submit digital representations of practical production work and forms of creative expression for summative high-stakes assessment. The study set out to determine the feasibility of students creating and submitting these digital representations for assessment and to identify which of analytical or comparative pairs scoring generated the more reliable scores. This paper proposes that scoring digital representations of creative practical work submitted by students is a viable alternative to traditional approaches to assessment. L’évaluation externe à enjeux élevés dans les cours pratiques se heurte à des problèmes qui se répercutent sur la gestion, la validité et la fiabilité de la notation. Des approches différentes de l'évaluation utilisant des technologies numériques ont le potentiel de remédier à ces problèmes. Cet article décrit une étude consacrée à l'utilisation de ces technologies pour créer et soumettre des représentations numériques de travaux pratiques de production et de création pour une évaluation sommative à enjeux élevés. L'étude visait à déterminer si la création de ces représentations numériques par les étudiants et leur soumission pour évaluation étaient réalisables. Elle visait aussi à identifier quel système de notation de groupe, analytique ou comparatif, générait les scores les plus fiables. Cet article soutient que noter les représentations numériques de travaux pratiques soumis par les étudiants offre un choix viable aux approches traditionnelles d'évaluation.

Tamoxifen improves cholinergically modulated cognitive performance in postmenopausal women

Tamoxifen (TMX) is a selective estrogen receptor modulator that is used as an estrogen receptor antagonist for the treatment and prevention of breast cancer. Whether TMX has antagonist activities in the human brain is less clear and its effects on cognitive function have not been experimentally explored. This study examined how TMX affected cognitive performance in older women using a model of anticholinergic drug-induced cognitive dysfunction. Twenty-one postmenopausal women were administered 20 mg of oral TMX or placebo for 3 months. Participants then took part in five drug challenges using the anticholinergic antinicotinic agent mecamylamine (MECA) and antimuscarinic agent scopolamine (SCOP) and were tested on a comprehensive battery including tasks of attention and psychomotor function, verbal episodic memory, and spatial navigation. After a 3-month placebo washout, participants were then crossed over to the alternate treatment and repeated the drug challenges after 3 months. Compared with placebo treatment, TMX significantly attenuated the impairment from cholinergic blockade on tasks of verbal episodic memory and spatial navigation, but effects on attentional/psychomotor tasks were more variable. Analysis by APOE genotype showed that APO ɛ4+ women showed a greater beneficial effect of TMX on reversing the cholinergic impairment than APO ɛ4- women on most tasks. This study provides evidence that TMX may act as an estrogen-like agonist to enhance cholinergic system activity and hippocampally mediated learning.

Organizational Structure Reduces Processing Load in the Prefrontal Cortex During Discourse Processing of Written Text: Implications for High-Level Reading Issues After TBI

Adults with traumatic brain injury (TBI) can demonstrate marked difficulty producing discourse during story retell and story generation tasks. Changes in discourse production have been detailed in terms of fewer content units and infrequent use of story grammar elements essential for organization. One implication is that poor use of story grammar elements during discourse production may signal reduced ability to utilize these elements in other communication realms (e.g., reading comprehension). The neural architecture that supports discourse organization, primarily the medial prefrontal cortex, is particularly susceptible to damage secondary to acquired brain injury. In this event related functional magnetic resonance imaging (fMRI) study, we describe cortical activation patterns of unimpaired readers as they are presented with discourse that is varied in terms of structural organization. The results suggest reading discourse with less structure is associated with increased cortical activity (e.g., higher processing demands) as compared to reading discourse with more traditional structural cues (e.g., story grammar). We discuss cortical areas implicated and potential implications for supporting discourse communication in persons following TBI.

Nicotine treatment of mild cognitive impairment: a 6-month double-blind pilot clinical trial

OBJECTIVE

To preliminarily assess the safety and efficacy of transdermal nicotine therapy on cognitive performance and clinical status in subjects with mild cognitive impairment (MCI).

METHODS

Nonsmoking subjects with amnestic MCI were randomized to transdermal nicotine (15 mg per day or placebo) for 6 months. Primary outcome variables were attentional improvement assessed with Connors Continuous Performance Test (CPT), clinical improvement as measured by clinical global impression, and safety measures. Secondary measures included computerized cognitive testing and patient and observer ratings.

RESULTS

Of 74 subjects enrolled, 39 were randomized to nicotine and 35 to placebo. 67 subjects completed (34 nicotine, 33 placebo). The primary cognitive outcome measure (CPT) showed a significant nicotine-induced improvement. There was no statistically significant effect on clinician-rated global improvement. The secondary outcome measures showed significant nicotine-associated improvements in attention, memory, and psychomotor speed, and improvements were seen in patient/informant ratings of cognitive impairment. Safety and tolerability for transdermal nicotine were excellent.

CONCLUSION

This study demonstrated that transdermal nicotine can be safely administered to nonsmoking subjects with MCI over 6 months with improvement in primary and secondary cognitive measures of attention, memory, and mental processing, but not in ratings of clinician-rated global impression. We conclude that this initial study provides evidence for nicotine-induced cognitive improvement in subjects with MCI; however, whether these effects are clinically important will require larger studies.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that 6 months of transdermal nicotine (15 mg/day) improves cognitive test performance, but not clinical global impression of change, in nonsmoking subjects with amnestic MCI.

Estradiol interacts with the cholinergic system to affect verbal memory in postmenopausal women: evidence for the critical period hypothesis

Estradiol has been shown to interact with the cholinergic system to affect cognition in postmenopausal women. This study further investigated the interaction of estradiol and cholinergic system functioning on verbal memory and attention in two groups of healthy younger (ages 50-62) and older (ages 70-81) postmenopausal women. Twenty-two postmenopausal women were randomly and blindly placed on 1 mg of 17-beta estradiol orally for 1 month then 2 mg for 2 months or matching placebo pills after which they participated in three anticholinergic challenge sessions when verbal memory and attention were assessed. Subjects were administered either the antimuscarinic drug scopolamine (SCOP), the antinicotinic drug mecamylamine (MECA), or placebo. After the first challenge phase, they were crossed over to the other hormone treatment for another 3 months and repeated the challenges. Results showed that estradiol pretreatment significantly attenuated the anticholinergic drug-induced impairments on a test of episodic memory (the Buschke Selective Reminding Task) for the younger group only, while estradiol treatment impaired performance of the older group. The results suggest that younger subjects may experience more cholinergic benefit from estradiol treatment than older subjects, supporting the concept of a critical period for postmenopausal estrogen use.

Sex differences in visual-spatial learning using a virtual water maze in pre-pubertal children

Gonadal steroid effects during puberty are often hypothesized to account for the male advantage seen in certain spatial tasks. One spatial task where males consistently show better performance than females is the Morris Water Task in which subjects must navigate to a goal location in a pool. We examined whether sex differences exist in pre-pubertal children completing a Virtual Morris Water Task, which has previously shown strong sex differences in adults. Pre-pubertal boys show superior performance to similar-aged girls, as evidenced by shorter latencies to find the platform and stronger preferences for the platform location during a probe trial. These results suggest that sex differences in spatial learning and memory exist prior to puberty and do not appear to require the effects of sex hormones at puberty. Rather, these differences may reflect early-life hormonal effects on hippocampal-dependent processes and may suggest different preferential learning strategies by boys and girls.

Estrogen treatment effects on anticholinergic-induced cognitive dysfunction in normal postmenopausal women

Estrogen has been shown to interact with the cholinergic system and influence cognition in animal models. This study investigated the interaction of estrogen and cholinergic system functioning and the effects of this interaction on cognitive task performance in healthy older women. Fifteen post-menopausal women were randomly and blindly placed on 1 mg of 17-beta estradiol or placebo for 3 months after which they participated in five anticholinergic challenge sessions, where they were administered one of two doses of the antimuscarinic drug scopolamine (SCOP) or the antinicotinic drug mecamylamine (MECA) or placebo. After the first challenge phase, they were crossed over to the other hormone treatment for another 3 months and repeated the challenges. Performance in multiple domains of cognition was assessed during anticholinergic drug challenge, including attention and verbal and nonverbal learning and memory. Results showed that estrogen pretreatment attenuated the anticholinergic drug-induced impairments on tests of attention and tasks with speed components. This study is the first to demonstrate the interaction of estrogen and the cholinergic system and the effects on cognitive performance in humans. The results suggest that estrogen status may affect cholinergic system tone and may be important for cholinergic system integrity.

Nicotinic acetylcholine receptor system and neuropsychiatric disorders

Investigations into the neurobiology, and biophysical and pharmacological properties of nicotinic receptors, also known as nicotinic acetylcholine receptors (nAChRs), have led to an improved understanding of their role in a variety of neuropsychiatric disorders. There is a growing body of evidence linking alterations in nicotinic receptor number and/or function to conditions such as schizophrenia, Alzheimer's disease, Parkinson's disease, anxiety disorders, mood disorders, and attention deficit-hyperactivity disorder. The implications of nicotine receptor modulation upon the clinical expression and progression of these disorders is currently under investigation, utilizing techniques that include psychopharmacological, cognitive, electrophysiological and neuroimaging analysis. This review attempts to outline evidence pertaining to the role of the nicotinic receptor system in various neuropsychiatric disorders in the context of understanding appropriate targets for therapeutic drug development.

Nicotine and Nicotinic Receptor Involvement in Neuropsychiatric Disorders

Advances in the understanding of the neurobiology of the nicotinic receptor have started to be matched by an appreciation of the potential role of these receptors in a variety of neuropsychiatric disorders. While alterations in nicotinic receptor number and/or function have been associated with such conditions as Alzheimer's disease for several years, there is increasing evidence that nicotinic receptor function may play a significant role in other disorders as well including schizophrenia, Parkinson's disease, anxiety disorders, and attention deficit-hyperactivity disorder (ADHD). Research in our laboratory and those of other investigators have utilized sophisticated psychopharmacological, cognitive, electrophysiological, neuroimaging and other techniques to assess the impact of nicotinic receptor modulation on the clinical expression of these disorders. This manuscript reviews data, both experimental and clinical, relating to the role of nicotine and/or nicotinic receptor function in a variety of neuropsychiatric disorders with the perspective of developing appropriate targets for therapeutic drug development.

An 8-week multicenter, parallel-group, double-blind, placebo-controlled study of sertraline in elderly outpatients with major depression

OBJECTIVE

There have been few placebo-controlled trials of selective serotonin reuptake inhibitors for depressed elderly patients. This placebo-controlled study of sertraline was designed to confirm the results of non-placebo-controlled trials.

METHOD

The subjects were outpatients age 60 years or older who had a DSM-IV diagnosis of major depressive disorder and a total score on the 17-item Hamilton Depression Rating Scale of 18 or higher. The patients were randomly assigned to 8 weeks of double-blind treatment with placebo or a flexible daily dose of 50 or 100 mg of sertraline. The primary outcome variables were the Hamilton scale and Clinical Global Impression (CGI) scales for severity and improvement.

RESULTS

A total of 371 patients assigned to sertraline and 376 assigned to placebo took at least one dose. At endpoint, the patients receiving sertraline evidenced significantly greater improvements than those receiving placebo on the Hamilton depression scale and CGI severity and improvement scales. The mean changes from baseline to endpoint in Hamilton score were -7.4 points (SD=6.3) for sertraline and -6.6 points (SD=6.4) for placebo. The rate of CGI-defined response at endpoint was significantly higher for sertraline (45%) than for placebo (35%), and the time to sustained response was significantly shorter for sertraline (median, 57 versus 61 days). There were few discontinuations due to treatment-related adverse events, 8% for sertraline and 2% for placebo.

CONCLUSIONS

Sertraline was effective and well tolerated by older adults with major depression, although the drug-placebo difference was not large in this 8-week trial.

DHEA treatment of Alzheimer's disease: a randomized, double-blind, placebo-controlled study

OBJECTIVE

To compare the efficacy and tolerability of dehydroepiandrosterone (DHEA) vs placebo in AD.

METHOD

Fifty-eight subjects with AD were randomized to 6 month's treatment with DHEA (50 mg per os twice a day; n = 28) or placebo (n = 30) in a multi-site, double-blind pilot trial. Primary efficacy measures assessed cognitive functioning (the AD Assessment Scale-Cognitive [ADAS-Cog]) and observer-based ratings of overall changes in severity (the Clinician's Interview-Based Impression of Change with Caregiver Input [CIBIC-Plus]). At baseline, 3 months, and 6 months, the ADAS-Cog was administered, and at 3 and 6 months, the CIBIC-Plus was administered. The 6-month time point was the primary endpoint.

RESULTS

Nineteen DHEA-treated subjects and 14 placebo-treated subjects completed the trial. DHEA was relatively well-tolerated. DHEA treatment, relative to placebo, was not associated with improvement in ADAS-Cog scores at month 6 (last observation carried forward; p = 0.10); transient improvement was noted at month 3 (p = 0.014; cutoff for Bonferroni significance = 0.0125). No difference between treatments was seen on the CIBIC-Plus at either the 6-month or the 3-month time points.

CONCLUSIONS

DHEA did not significantly improve cognitive performance or overall ratings of change in severity in this small-scale pilot study. A transient effect on cognitive performance may have been seen at month 3, but narrowly missed significance.

Extended-release physostigmine in Alzheimer disease: a multicenter, double-blind, 12-week study with dose enrichment. Physostigmine Study Group

BACKGROUND

The efficacy of extended-release physostigmine salicylate, an acetylcholinesterase inhibitor, was evaluated in 850 subjects with mild-to-moderate Alzheimer disease (AD) in a multicenter trial.

METHODS

Subjects initially entered a dose-enrichment phase in which they received 1 week each of physostigmine salicylate, 24 mg/d and 30 mg/d, and daily placebo. Among the subjects who completed this phase, 35.9% responded to physostigmine treatment, whereas 62.4% were considered nonresponders, and 1.6% could not be evaluated because of missing data. After a 4-week placebo-washout phase, 176 responder subjects were randomized to receive their best dose of physostigmine or placebo in a 12-week double-blind phase. Primary efficacy measures included the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog), the Clinician's Interview-Based Impression of Change With Caregiver Input (CIBIC+), and the Clinical Global Impression of Change (CGIC).

RESULTS

In the intent-to-treat analysis of the double-blind phase, physostigmine-treated subjects scored -2.02 points better than placebo-treated subjects on the ADAS-Cog (F1,167 = 6.42 [P = .01]) and 0.33 points higher on the CIBIC+ (F1,150 = 5.68 [P = .02]). No significant improvement was observed on the CGIC or the secondary outcome measures. Nausea and vomiting were experienced by 47.0% of all physostigmine-treated subjects during the double-blind phase.

CONCLUSIONS

Physostigmine demonstrated a statistically significant benefit compared with placebo on a clinical global rating of change and an objective test of cognitive function. Given the frequency of gastrointestinal side effects, the role of this agent in clinical use remains to be determined.

Daily energy expenditure in free-living non-institutionalized Alzheimer's patients: a doubly labeled water study

Weight loss is common in Alzheimer's disease (AD), but its pathogenesis is poorly understood. It is unclear whether an elevated daily energy expenditure contributes to the weight loss. We tested the hypothesis that daily energy expenditure is higher in AD patients compared to healthy elderly. Thirty AD (73 +/- 8 years; Mini-Mental State Examination score: 16 +/- 8) and 103 healthy elderly (69 +/- 7 years) were characterized for daily energy expenditure and its components (resting and free-living physical activity energy expenditure) from doubly labeled water and indirect calorimetry. Fat-free mass and fat mass were measured from dual energy X-ray absorptiometry. Fat-free mass tended to be lower in AD patients (45 +/- 9 kg) versus healthy elderly (49 +/- 10 kg; p = 0.07), whereas no differences were noted in fat mass between groups. Daily energy expenditure was 14% lower in AD (1901 +/- 517 kcal/d) compared to healthy elderly (2213 +/- 513 kcal/d; p < 0.001), due to lower resting (1287 +/- 227 versus 1418 +/- 246 kcal/d; p < 0.01) and physical activity energy expenditures (425 +/- 317 versus 574 +/- 342 kcal/d; p < 0.05). No differences in energy expenditure were noted between groups after controlling for differences in body composition. Daily energy expenditure was examined in a subgroup (n = 11) of AD patients who lost significant body weight (5.6 +/- 2.3 kg) within the past year. There was a lower daily energy expenditure in cachectic AD patients (1799 +/- 474 kcal/d) versus non-cachectic patients (1960 +/- 544 kcal/d) and healthy elderly (2213 +/- 513 kcal/d; p < 0.01). Similarly, no differences in energy expenditure were noted between groups after controlling for differences in body composition. We conclude that absolute levels of daily energy expenditure are lower in AD patients due to their lower body mass. However, after taking into account differences in body composition, daily energy expenditure in AD patients is appropriate for their metabolic size. The hypothesis that elevated daily energy expenditure contributes to weight loss in AD is not supported by these findings.

No evidence for a higher resting metabolic rate in noninstitutionalized Alzheimer's disease patients

OBJECTIVE

It has previously been suggested that Alzheimer's disease patients have higher resting energy requirements than healthy individuals, which may contribute to their unexplained weight loss. We examined whether resting metabolic rate, the largest component of daily energy expenditure, is elevated in Alzheimer's patients compared with healthy older controls.

DESIGN

Cross-sectional.

SETTING

General Clinical Research Center and Baltimore VA Medical Center.

PATIENTS

Twenty-five noninstitutionalized demented patients (74 +/- 8 years; mean +/- SD) with a wide range of Mini-Mental Examination scores (1 to 20) and 73 healthy older individuals (69 +/- 7 years).

MEASUREMENTS

Resting metabolic rate was measured by indirect calorimetry, fat-free mass and fat mass by dual energy X-ray absorptiometry, and daily energy intake by food diaries.

RESULTS

No differences in fat-free mass and fat mass were noted between Alzheimer's disease patients and healthy older controls. Resting metabolic rate was similar in Alzheimer's disease patients (5446 +/- 962 kJ/day) and healthy older individuals (5647 +/- 887 kJ/day). These results persisted when resting metabolic rate was statistically adjusted for differences in body composition and age.

CONCLUSION

These results provide no evidence for an elevation in resting energy requirements in noninstitutionalized demented patients.

Society for Research on Nicotine and Tobacco

The proceedings of the inaugural scientific meeting of the Society for Research on Nicotine and Tobacco (SRNT) are summarized. The primary objective of the meeting was to foster the exchange of information on the effects of nicotine and tobacco use, as well as factors which influence their use, drawing from biological, behavioral and social sciences. Much of this research can be viewed as a tale of "two" drugs--nicotine as a key to an important public health problem, and nicotine as a classical tool of physiological and pharmacological research. A historical overview of research on "both" drugs is provided first. Public policy alternatives for reducing the prevalence of tobacco use have been derived in part from basic and clinical research results and are briefly outlined. Evidence for genetic determinants on nicotine use and effects is presented using data from twin studies and from molecular genetic research with humans and animals. Consistent with this research, there is evidence of individual differences in pharmacokinetics and effects of nicotine, which could account for differences in smoking behavior and nicotine dependence. Finally, recent developments in the therapeutic uses of nicotine and novel nicotinic agonists with schizophrenia, Alzheimer's disease, Parkinson's disease, Tourette's syndrome and ulcerative colitis are presented. Overall, the research presented at the meeting demonstrated the vast diversity of areas of study involving nicotine and tobacco, as well as the rich opportunities for cross-communication among researchers from different disciplines.