The Impact of Financial Reward Contingencies on Cognitive Function Profiles in Adult ADHD

Objectives

Although it is well established that cognitive performance in children with attention-deficit/hyperactivity disorder (ADHD) is affected by reward and that key deficits associated with the disorder may thereby be attenuated or even compensated, this phenomenon in adults with ADHD has thus far not been addressed. Therefore, the aim of the present study was to examine the motivating effect of financial reward on task performance in adults with ADHD by focusing on the domains of executive functioning, attention, time perception, and delay aversion.

Methods

We examined male and female adults aged 18–40 years with ADHD (n = 38) along with a matched control group (n = 40) using six well-established experimental paradigms.

Results

Impaired performance in the ADHD group was observed for stop-signal omission errors, n-back accuracy, reaction time variability in the continuous performance task, and time reproduction accuracy, and reward normalized time reproduction accuracy. Furthermore, when rewarded, subjects with ADHD exhibited longer reaction times and fewer false positives in the continuous performance task, which suggests the use of strategies to prevent impulsivity errors.

Conclusions

Taken together, our results support the existence of both cognitive and motivational mechanisms for the disorder, which is in line with current models of ADHD. Furthermore, our data suggest cognitive strategies of “stopping and thinking” as a possible underlying mechanism for task improvement that seems to be mediated by reward, which highlights the importance of the interaction between motivation and cognition in adult ADHD.     

Gait Velocity Is an Indicator of Cognitive Performance in Healthy Middle-Aged Adults

Psychomotor retardation, especially motor and cognitive slowing down, has been described many times in the elderly but to our knowledge, has never been examined in healthy middle-aged adults. The present study explores whether walking time may provide an early signal of cognitive performance, using 266 healthy adults ([18–65] years old, mean age: 45.7±12.9 years) who were also subdivided in 2 groups: under or over 50. Walking time (50 meters) and cognitive performances (mini-mental state examination, Benton Visual Retention Test and Rey Complex Figure) were assessed; total psychometric score was the sum of individual test scores. Analyses were controlled for age, gender, education level, height and weight. The mean psychometric scores were within the normal range. A substantial proportion of subjects exhibited low performance in some aspects of visuospatial memory, particularly in the older subset. In the total population, walking time was negatively correlated with all cognitive tests, particularly to total psychometric score (R = −0.817, p<0.0001); the unique contribution of walking time on all cognitive scores was very high (delta R-squared = 0.496). In the older subset, performances on walk and cognition were lower than in the younger subset. Total psychometric score showed the strongest correlation with walking time in the older subset (R = −0.867; p<0.001). In all subsets, walking time was the main explanatory variable of the total psychometric score (delta R-squared: ≤ 49 = 0.361; ≥50 = 0.613). These findings indicate that i) a significant proportion of adults without cognitive complaints exhibit low cognitive performance including visuospatial memory and longer walking time, ii) cognitive functioning is strongly correlated to walking time in healthy middle-aged adults, iii) gait velocity (GV) could be an indicator of cognitive performance in some important cognitive domains. These results warrant further investigation because such data may represent a marker for the detection of middle-aged adults who are at risk for further cognitive decline.     

Attentional Control and Subjective Executive Function in Treatment-Naive Adults with Attention Deficit Hyperactivity Disorder

We investigated performance-derived measures of executive control, and their relationship with self- and informant reported executive functions in everyday life, in treatment-naive adults with newly diagnosed Attention Deficit Hyperactivity Disorder (ADHD; n = 36) and in healthy controls (n = 35). Sustained attentional control and response inhibition were examined with the Test of Variables of Attention (T.O.V.A.). Delayed responses, increased reaction time variability, and higher omission error rate to Go signals in ADHD patients relative to controls indicated fluctuating levels of attention in the patients. Furthermore, an increment in NoGo commission errors when Go stimuli increased relative to NoGo stimuli suggests reduced inhibition of task-irrelevant stimuli in conditions demanding frequent responding. The ADHD group reported significantly more cognitive and behavioral executive problems than the control group on the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A). There were overall not strong associations between task performance and ratings of everyday executive function. However, for the ADHD group, T.O.V.A. omission errors predicted self-reported difficulties on the Organization of Materials scale, and commission errors predicted informant reported difficulties on the same scale. Although ADHD patients endorsed more symptoms of depression and anxiety on the Achenbach System of Empirically Based Assessment (ASEBA) than controls, ASEBA scores were not significantly associated with T.O.V.A. performance scores. Altogether, the results indicate multifaceted alteration of attentional control in adult ADHD, and accompanying subjective difficulties with several aspects of executive function in everyday living. The relationships between the two sets of data were modest, indicating that the measures represent non-redundant features of adult ADHD.     

Relative Deprivation,Poverty, and Subjective Health: JAGES Cross-Sectional Study

To evaluate the association between relative deprivation (lacking daily necessities) and subjective health in older Japanese adults, we performed a cross-sectional analysis using data from the Japan Gerontological Evaluation Study (JAGES). The data were obtained from functionally independent residents aged ≥65 years from 24 municipalities in Japan (n = 24,742). Thirteen items in three dimensions were used to evaluate relative deprivation of material conditions. Approximately 28% of older Japanese people indicated that they lacked some daily necessities (non-monetary poverty). A two-level Poisson regression analysis revealed that relative deprivation was associated with poor self-rated health (PR = 1.3–1.5) and depressive symptoms (PR = 1.5–1.8) in both men and women, and these relationships were stronger than those observed in people living in relative poverty (monetary poverty). The interaction effect between relative deprivation and relative poverty was not associated with poor health. As a dimension of the social determinants of health, poverty should be evaluated from a multidimensional approach, capturing not only monetary conditions but also material-based, non-monetary conditions.     

Relationship between Auditory and Cognitive Abilities in Older Adults

Objective

The objective was to evaluate the association of peripheral and central hearing abilities with cognitive function in older adults.

Methods

Recruited from epidemiological studies of aging and cognition at the Rush Alzheimer’s Disease Center, participants were a community-dwelling cohort of older adults (range 63–98 years) without diagnosis of dementia. The cohort contained roughly equal numbers of Black (n=61) and White (n=63) subjects with groups similar in terms of age, gender, and years of education. Auditory abilities were measured with pure-tone audiometry, speech-in-noise perception, and discrimination thresholds for both static and dynamic spectral patterns. Cognitive performance was evaluated with a 12-test battery assessing episodic, semantic, and working memory, perceptual speed, and visuospatial abilities.

Results

Among the auditory measures, only the static and dynamic spectral-pattern discrimination thresholds were associated with cognitive performance in a regression model that included the demographic covariates race, age, gender, and years of education. Subsequent analysis indicated substantial shared variance among the covariates race and both measures of spectral-pattern discrimination in accounting for cognitive performance. Among cognitive measures, working memory and visuospatial abilities showed the strongest interrelationship to spectral-pattern discrimination performance.

Conclusions

For a cohort of older adults without diagnosis of dementia, neither hearing thresholds nor speech-in-noise ability showed significant association with a summary measure of global cognition. In contrast, the two auditory metrics of spectral-pattern discrimination ability significantly contributed to a regression model prediction of cognitive performance, demonstrating association of central auditory ability to cognitive status using auditory metrics that avoided the confounding effect of speech materials.     

Epidemiology of Treated Attention-Deficit/Hyperactivity Disorder (ADHD) across the Lifespan in Taiwan: A Nationwide Population-Based Longitudinal Study

Objectives

We used insurance claims of a nationally representative population-based cohort to assess the longitudinal treated prevalence and incidence of attention-deficit/hyperactivity disorder (ADHD) in children, adolescents and adults.

Methods

Participants were identified from among National Health Insurance enrollees in Taiwan from 1999 to 2005. We identified study subjects who had at least one service claim during these years with a principal diagnosis of ADHD. A total of 6,173 patients were recorded in the treated ADHD cohort during the 6-year study.

Results

There was a significant increase in the treated prevalence rate of ADHD during the study period, from 64.65 per 100,000 in 2000 to 145.40 per 100,000 in 2005 (p = .001). An increase in the treated incidence rate of ADHD, from 44.67 per 100,000 in 2000 to 81.20 per 100,000 in 2005, was also observed (p = .013). However, the treated prevalence of ADHD was still lower than that of the community data in Taiwan. The peak treated prevalence of ADHD was at age 7–12 years for both males and females, and the peak treated incidence of ADHD was at age 0–6 for females and age 7–12 for males. Overall, the treated incidence and prevalence rates dropped abruptly after age 13–18 (both p<.001) for males and females (p<.001 for both). Male vs. female ratios of treated prevalence and incidence were both above 1 before age 25–30 years, but below 1 thereafter.

Conclusion

Although an increasing number of people with ADHD sought treatment during 1999–2005 in Taiwan, the treated prevalence of ADHD was still lower than that of the community data. The treated incidence and prevalence of ADHD fell dramatically after age 13–18. However, more women than men sought treatment in adulthood. There may be under-diagnosis and under-treatment of ADHD, especially among females and adults.     

Dissociable Patterns in the Control of Emotional Interference in Adults with Attention-Deficit/Hyperactivity Disorder (ADHD) and in Adults with Alcohol Dependence

Objectives

To effectively manage current task demands, attention must be focused on task-relevant information while task-irrelevant information is rejected. However, in everyday life, people must cope with emotions, which may interfere with actual task demands and may challenge functional attention allocation. Control of interfering emotions has been associated with the proper functioning of the dorsolateral prefrontal cortex (DLPFC). As DLPFC dysfunction is evident in subjects with ADHD and in subjects with alcohol dependence, the current study sought to examine the bottom-up effect of emotional distraction on task performance in both disorders.

Methods

Male adults with ADHD (n = 22), male adults with alcohol dependence (n = 16), and healthy controls (n = 30) performed an emotional working memory task (n-back task). In the background of the task, we presented neutral and negative stimuli that varied in emotional saliency.

Results

In both clinical groups, a working memory deficit was evident. Moreover, both clinical groups displayed deficient emotional interference control. The n-back performance of the controls was not affected by the emotional distractors, whereas that of subjects with ADHD deteriorated in the presence of low salient distractors, and that of alcoholics did not deteriorate until high salient distractors were presented. Subsequent to task performance, subjects with ADHD accurately recognized more distractors than did alcoholics and controls. In alcoholics, picture recognition accuracy was negatively associated with n-back performance, suggesting a functional association between the ability to suppress emotional distractors and successful task performance. In subjects with ADHD, performance accuracy was negatively associated with ADHD inattentive symptoms, suggesting that inattention contributes to the performance deficit.

Conclusions

Subjects with ADHD and alcoholics both display an emotional interference control deficit, which is especially pronounced in subjects with ADHD. Beyond dysfunctional attention allocation processes, a more general attention deficit seems to contribute to the more pronounced performance deficit pattern in ADHD.     

Individual Differences in Fornix Microstructure and Body Mass Index

The prevalence of obesity and associated health conditions is increasing in the developed world. Obesity is related to atrophy and dysfunction of the hippocampus and hippocampal lesions may lead to increased appetite and weight gain. The hippocampus is connected via the fornix tract to the hypothalamus, orbitofrontal cortex, and the nucleus accumbens, all key structures for homeostatic and reward related control of food intake. The present study employed diffusion MRI tractography to investigate the relationship between microstructural properties of the fornix and variation in Body Mass Index (BMI), within normal and overweight ranges, in a group of community-dwelling older adults (53–93 years old). Larger BMI was associated with larger axial and mean diffusivity in the fornix (r = 0.64 and r = 0.55 respectively), relationships that were most pronounced in overweight individuals. Moreover, controlling for age, education, cognitive performance, blood pressure and global brain volume increased these correlations. Similar associations were not found in the parahippocampal cingulum, a comparison temporal association pathway. Thus, microstructural changes in fornix white matter were observed in older adults with increasing BMI levels from within normal to overweight ranges, so are not exclusively related to obesity. We propose that hippocampal-hypothalamic-prefrontal interactions, mediated by the fornix, contribute to the healthy functioning of networks involved in food intake control. The fornix, in turn, may display alterations in microstructure that reflect weight gain.     

The Strengths and Difficulties Questionnaire as a Predictor of Parent-Reported Diagnosis of Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder

The Strengths and Difficulties Questionnaire (SDQ) is widely used as an international standardised instrument measuring child behaviour. The primary aim of our study was to examine whether behavioral symptoms measured by SDQ were elevated among children with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) relative to the rest of the population, and to examine the predictive value of the SDQ for outcome of parent-reported clinical diagnosis of ASD/ADHD. A secondary aim was to examine the extent of overlap in symptoms between children diagnosed with these two disorders, as measured by the SDQ subscales. A cross-sectional secondary analysis of data from the Millennium Birth Cohort (n = 19,519), was conducted. Data were weighted to be representative of the UK population as a whole. ADHD or ASD identified by a medical doctor or health professional were reported by parents in 2008 and this was the case definition of diagnosis; (ADHD n = 173, ASD n = 209, excluding twins and triplets). Study children''s ages ranged from 6.3–8.2 years; (mean 7.2 years). Logistic regression was used to examine the association between the parent-reported clinical diagnosis of ASD/ADHD and teacher and parent-reported SDQ subscales. All SDQ subscales were strongly associated with both ASD and ADHD. There was substantial co-occurrence of behavioral difficulties between children diagnosed with ASD and those diagnosed with ADHD. After adjustment for other subscales, the final model for ADHD, contained hyperactivity/inattention and impact symptoms only and had a sensitivity of 91% and specificity of 90%; (AUC) = 0.94 (95% CI, 0.90–0.97). The final model for ASD was composed of all subscales except the ‘peer problems’ scales, indicating of the complexity of behavioural difficulties that may accompany ASD. A threshold of 0.03 produced model sensitivity and specificity of 79% and 93% respectively; AUC = 0.90 (95% CI, 0.86–0.95). The results support changes to DSM-5 removing exclusivity clauses.     

Estimating Cognitive Reserve in Healthy Adults Using the Cognitive Reserve Scale

The concept of cognitive reserve emerged from observed disparities between brain pathology and clinical symptoms. It may explain better neuropsychological performance in healthy individuals. The objectives of this study were to measure reserve in healthy subjects using a new Cognitive Reserve Scale (CRS), analyze the internal consistency of the CRS, and analyze validity evidence. A total of 117 healthy individuals were divided into two groups: 87 adults (aged 18–64 years) and 30 elderly adults (≥65 years). All subjects completed the CRS and a comprehensive neuropsychological battery. The internal consistency of the scale was satisfactory (α = 0.77). No significant differences were observed between genders (t = 0.51, p = 0.611), and age was corrected by averaging the CRS score. The study of validity evidence showed that education affected the CRS (t = −2.98, p = 0.004, partial h² = 0.07) and there was no significant relationship between the CRS and IQ (r = 0.09, p = 0.33). Occupational attainment and the CRS were not related (F_2,116 = 0.11, p = 0.898). In line with previous studies on reserve, heterogeneity was observed in the analyses of relationships between the CRS and cognitive performance. There were significant relationships between CRS score and the Verbal Learning Spanish–Complutense Test last trial (r = 0.24, p = 0.009), sum (r = 0.32, p = 0.000), short-term (r = 0.29, p = 0.002) and long-term memory (r = 0.22, p = 0.018), Matrix Reasoning subtest (r = 0.20, p = 0.027) and Block Design subtest (r = 0.20, p = 0.029). No other neuropsychological variables correlated with the CRS (p>0.05). The CRS is a reliable instrument that reflects the frequency of participation in brain-stimulating activities across the lifetime. The associations between the CRS and education and neuropsychological performance support validity evidence.     

Disruptions in Brain Networks of Older Fallers Are Associated with Subsequent Cognitive Decline: A 12-Month Prospective Exploratory Study

Cognitive impairment and impaired mobility are major public health concerns. There is growing recognition that impaired mobility is an early biomarker of cognitive impairment and dementia. The neural basis for this association is currently unclear. We propose disrupted functional connectivity as a potential mechanism. In this 12-month prospective exploratory study, we compared functional connectivity of four brain networks– the default mode network (DMN), fronto-executive network (FEN), fronto-parietal network (FPN), and the primary motor sensory network (SMN) – between community-dwelling older adults with ≥ two falls in the last 12 months and their non-falling counterparts (≤ one fall in the last 12 months). Functional connectivity was examined both at rest and during a simple motor tapping task. Compared with non-fallers, fallers showed more connectivity between the DMN and FPN during right finger tapping (p = 0.04), and significantly less functional connectivity between the SMN and FPN during rest (p≤0.05). Less connectivity between the SMN and FPN during rest was significantly associated with greater decline in both cognitive function and mobility over the12-month period (r = −0.32 and 0.33 respectively; p≤0.04). Thus, a recent history of multiple falls among older adults without a diagnosis of dementia may indicate sub-clinical changes in brain function and increased risk for subsequent decline.     

Non-Consent to a Wrist-Worn Accelerometer in Older Adults: The Role of Socio-Demographic,Behavioural and Health Factors

Background

Accelerometers, initially waist-worn but increasingly wrist-worn, are used to assess physical activity free from reporting-bias. However, its acceptability by study participants is unclear. Our objective is to assess factors associated with non-consent to a wrist-mounted accelerometer in older adults.

Methods

Data are from 4880 Whitehall II study participants (1328 women, age range = 60–83), requested to wear a wrist-worn accelerometer 24 h every day for 9 days in 2012/13. Sociodemographic, behavioral, and health-related factors were assessed by questionnaire and weight, height, blood pressure, cognitive and motor function were measured during a clinical examination.

Results

210 participants had contraindications and 388 (8.3%) of the remaining 4670 participants did not consent. Women, participants reporting less physical activity and less favorable general health were more likely not to consent. Among the clinical measures, cognitive impairment (Odds Ratio = 2.21, 95% confidence interval: 1.22–4.00) and slow walking speed (Odds Ratio = 1.38, 95% confidence interval: 1.02–1.86) were associated with higher odds of non-consent.

Conclusions

The rate of non-consent in our study of older adults was low. However, key markers of poor health at older ages were associated with non-consent, suggesting some selection bias in the accelerometer data.     

Statin Use and Cognitive Function: Population-Based Observational Study with Long-Term Follow-Up

We aimed to evaluate the association between statin use and cognitive function. Cognitive function was measured with the Ruff Figural Fluency Test (RFFT; worst score, 0; best score, 175 points) and the Visual Association Test (VAT; low performance, 0–10; high performance, 11–12 points) in an observational study that included 4,095 community-dwelling participants aged 35–82 years. Data on statin use were obtained from a computerized pharmacy database. Analysis were done for the total cohort and subsamples matched on cardiovascular risk (N = 1232) or propensity score for statin use (N = 3609). We found that a total of 904 participants (10%) used a statin. Statin users were older than non-users: mean age (SD) 61 (10) vs. 52 (11) years (p<0.001). The median duration of statin use was 3.8 (interquartile range, 1.6–4.5) years. Unadjusted, statin users had worse cognitive performance than non-users. The mean RFFT score (SD) in statin users and non-users was 58 (23) and 72 (26) points, respectively (p<0.001). VAT performance was high in 261 (29%) statin users and 1351 (43%) non-users (p<0.001). However, multiple regression analysis did not show a significant association of RFFT score with statin use (B, −0.82; 95%CI, −2.77 to 1.14; p = 0.41) nor with statin solubility, statin dose or duration of statin use. Statin users with high doses or long-term use had similar cognitive performance as non-users. This was found in persons with low as well as high cardiovascular risk, and in younger as well as older subjects. Also, the mean RFFT score per quintile of propensity score for statin use was comparable for statin users and non-users. Similar results were found for the VAT score as outcome measure. In conclusion, statin use was not associated with cognitive function. This was independent of statin dose or duration of statin use.     

Computerized Cognitive Training in Cognitively Healthy Older Adults: A Systematic Review and Meta-Analysis of Effect Modifiers

Background

New effective interventions to attenuate age-related cognitive decline are a global priority. Computerized cognitive training (CCT) is believed to be safe and can be inexpensive, but neither its efficacy in enhancing cognitive performance in healthy older adults nor the impact of design factors on such efficacy has been systematically analyzed. Our aim therefore was to quantitatively assess whether CCT programs can enhance cognition in healthy older adults, discriminate responsive from nonresponsive cognitive domains, and identify the most salient design factors.

Methods and Findings

We systematically searched Medline, Embase, and PsycINFO for relevant studies from the databases'' inception to 9 July 2014. Eligible studies were randomized controlled trials investigating the effects of ≥4 h of CCT on performance in neuropsychological tests in older adults without dementia or other cognitive impairment. Fifty-two studies encompassing 4,885 participants were eligible. Intervention designs varied considerably, but after removal of one outlier, heterogeneity across studies was small (I ² = 29.92%). There was no systematic evidence of publication bias. The overall effect size (Hedges'' g, random effects model) for CCT versus control was small and statistically significant, g = 0.22 (95% CI 0.15 to 0.29). Small to moderate effect sizes were found for nonverbal memory, g = 0.24 (95% CI 0.09 to 0.38); verbal memory, g = 0.08 (95% CI 0.01 to 0.15); working memory (WM), g = 0.22 (95% CI 0.09 to 0.35); processing speed, g = 0.31 (95% CI 0.11 to 0.50); and visuospatial skills, g = 0.30 (95% CI 0.07 to 0.54). No significant effects were found for executive functions and attention. Moderator analyses revealed that home-based administration was ineffective compared to group-based training, and that more than three training sessions per week was ineffective versus three or fewer. There was no evidence for the effectiveness of WM training, and only weak evidence for sessions less than 30 min. These results are limited to healthy older adults, and do not address the durability of training effects.

Conclusions

CCT is modestly effective at improving cognitive performance in healthy older adults, but efficacy varies across cognitive domains and is largely determined by design choices. Unsupervised at-home training and training more than three times per week are specifically ineffective. Further research is required to enhance efficacy of the intervention. Please see later in the article for the Editors'' Summary     

A population-based study of attention deficit/hyperactivity disorder symptoms and associated impairment in middle-aged adults

Attention deficit/hyperactivity disorder (ADHD) is the most prevalent childhood psychiatric condition. It frequently persists into adulthood and can have serious health and other adverse consequences. The majority of previous adult ADHD studies have focused on young adults so that relatively little is known about ADHD symptoms and their effects in mid and late life. In addition, effects of subclinical levels of attention deficit and hyperactivity have not been studied in detail. In this study we investigated ADHD symptoms and related impairment in a large population-based sample of middle-aged Australian adults (n = 2091; 47% male). Applying the WHO adult ADHD Self Report Screener (ASRS) we observed that 6.2% of participants had scores that were previously associated with ADHD diagnosis. No significant gender difference in the distribution of ASRS scores was observed. Multiple regression analyses indicated strong positive correlations between symptoms of ADHD and depression/anxiety and significant negative associations (p<0.01) with employment, financial stress, relationship quality, health and well-being measures in this age group. Importantly, associations were highly significant even when few ADHD symptoms were reported. Compared to the hyperactivity component, the inattention trait was particularly strongly associated and remained significant after controlling for depression/anxiety symptoms. Our study confirms previous findings and significantly adds to existing literature especially for an age-group that has not been well-studied. Our results suggest that ADHD symptoms continue to be associated with ill-health and functional impairment in mid-life and are, therefore, likely to be a major, previously unrecognized source of late-life morbidity with associated social and economic costs. Thus, there is a compelling need for better understanding and development of age-appropriate approaches to the diagnosis and treatment of ADHD in mid- to late-life.     

Family-Environmental Factors Associated with Attention Deficit Hyperactivity Disorder in Chinese Children: A Case-Control Study

Background

Attention deficit hyperactivity disorder (ADHD) is one of the most common psychiatric disorders, affecting an estimated 5 to 12% of school-aged children worldwide. From 15 to 19 million Chinese children suffer from ADHD. The aim of this study was to investigate the association between family-environmental factors and ADHD in a sample of Chinese children.

Methods

A pair-matched, case-control study was conducted with 161 ADHD children and 161 non-ADHD children of matching age and sex, all from 5–18 years of age. The ADHD subjects and the normal controls were all evaluated via structured diagnostic interviews. We examined the association between family-environmental factors and ADHD using the conditional multiple logistic regression with backward stepwise selection to predict the associated factors of ADHD.

Results

Having experienced emotional abuse and being a single child were both significant factors associated with children diagnosed with ADHD. ADHD subjects were more likely to have suffered from emotional abuse (OR = 11.09, 95% CI = 2.15–57.29, P = 0.004) and have been a single child in the family (OR = 6.32, 95% CI = 2.09–19.14, P = 0.001) when compared to normal controls. The results were not modified by other confounding factors.

Conclusion

Our findings provide evidence that family-environmental factors are associated with ADHD among children in China. These findings, if confirmed by future research, may help to decrease ADHD by increasing the awareness of the effects of childhood emotional abuse.     

Clinical and Biochemical Correlates of Serum L-Ergothioneine Concentrations in Community-Dwelling Middle-Aged and Older Adults

Background

Despite the increasing interest towards the biological role of L-ergothioneine, little is known about the serum concentrations of this unusual aminothiol in older adults. We addressed this issue in a representative sample of community-dwelling middle-aged and older adults.

Methods

Body mass index, estimated glomerular filtration rate, serum concentrations of L-ergothioneine, taurine, homocysteine, cysteine, glutathione, cysteinylglycine, and glutamylcysteine were evaluated in 439 subjects (age 55–85 years) randomly selected from the Hunter Community Study.

Results

Median L-ergothioneine concentration in the entire cohort was 1.01 IQR 0.78–1.33 µmol/L. Concentrations were not affected by gender (P = 0.41) or by presence of chronic medical conditions (P = 0.15). By considering only healthy subjects, we defined a reference interval for L-ergothioneine serum concentrations from 0.36 (90% CI 0.31–0.44) to 3.08 (90% CI 2.45–3.76) µmol/L. Using stepwise multiple linear regression analysis L-ergothioneine was negatively correlated with age (rpartial = −0.15; P = 0.0018) and with glutamylcysteine concentrations (rpartial = −0.13; P = 0.0063).

Conclusions

A thorough analysis of serum L-ergothioneine concentrations was performed in a large group of community-dwelling middle-aged and older adults. Reference intervals were established. Age and glutamylcysteine were independently negatively associated with L-ergothioneine serum concentration.     

Impact of the Non-Contributory Social Pension Program 70 y más on Older Adults’ Mental Well-Being

Background

In 2007, a non-contributory pension program was launched in rural areas of Mexico. The program consisted in a non-conditional cash transfer of US$40 monthly to all older adults (OA) aged 70 and over. We evaluate the effect of the program on mental well-being of its beneficiaries.

Methods and Findings

Quantitative and qualitative methods were used. For the quantitative component, we used the selection criteria established by the program (age and locality size) to form the Intervention (OA aged 70–74 residing in rural localities, <2500 inhabitants) and Control groups (OA aged 70–74, in localities with 2501–2700 inhabitants). Baseline data collection was conducted in 2007 where 5,465 OA were interviewed. The follow-up survey was conducted in 2008, and it was possible to interview 5,270 OA, with a response rate of 96%. A difference-in-difference linear probability model with individual fixed effect was used to estimate the impact of the program on mental well-being indicators. In 2009 a qualitative component was designed to explore possible causal pathways of such effect.

Results

After a year of exposure, the program had a significant effect on reduction of depressive symptoms (β = −0.06, CI_95% −0.12; −0.01) and an increase in empowerment indicators: OA participated in important household decisions (β = 0.09, CI_95% 0.03;0.15); and OA participated in household decisions pertaining to expenses (β = 0.11, CI_95% 0.05;0.18). Qualitative analysis found a strong trend showing a reduction of sadness, and feeling of increasing empowerment.

Conclusions

These results suggest that a non-conditional transfer in older ages have an impact beyond the economic sphere, impacting even the mental well-being. This effect could be explained because the pension produces feelings of safety and welfare. It is recommendable that governments should invest efforts towards universalizing the non-contributory pension programs in order to ensure a basic income for the elderly.     

Lipid Peroxidation and Depressed Mood in Community-Dwelling Older Men and Women

It has been hypothesized that cellular damage caused by oxidative stress is associated with late-life depression but epidemiological evidence is limited. In the present study we evaluated the association between urinary 8-iso-prostaglandin F_2α (8-iso-PGF_2α), a biomarker of lipid peroxidation, and depressed mood in a large sample of community-dwelling older adults. Participants were selected from the Health, Aging and Body Composition study, a community-based longitudinal study of older persons (aged 70–79 years). The present analyses was based on a subsample of 1027 men and 948 women free of mobility disability. Urinary concentration of 8-iso-PGF_2α was measured by radioimmunoassay methods and adjusted for urinary creatinine. Depressed mood was defined as a score greater than 5 on the 15-item Geriatric Depression Scale and/or use of antidepressant medications. Depressed mood was present in 3.0% of men and 5.5% of women. Depressed men presented higher urinary concentrations of 8-iso-PGF_2α than non-depressed men even after adjustment for multiple sociodemographic, lifestyle and health factors (p = 0.03, Cohen’s d = 0.30). This association was not present in women (depressed status-by-sex interaction p = 0.04). Our study showed that oxidative damage may be linked to depression in older men from a large sample of the general population. Further studies are needed to explore whether the modulation of oxidative stress may break down the link between late-life depression and its deleterious health consequences.     

White Matter Integrity Supports BOLD Signal Variability and Cognitive Performance in the Aging Human Brain

Decline in cognitive performance in old age is linked to both suboptimal neural processing in grey matter (GM) and reduced integrity of white matter (WM), but the whole-brain structure-function-cognition associations remain poorly understood. Here we apply a novel measure of GM processing–moment-to-moment variability in the blood oxygenation level-dependent signal (SD_BOLD)—to study the associations between GM function during resting state, performance on four main cognitive domains (i.e., fluid intelligence, perceptual speed, episodic memory, vocabulary), and WM microstructural integrity in 91 healthy older adults (aged 60-80 years). We modeled the relations between whole-GM SD_BOLD with cognitive performance using multivariate partial least squares analysis. We found that greater SD_BOLD was associated with better fluid abilities and memory. Most of regions showing behaviorally relevant SD_BOLD (e.g., precuneus and insula) were localized to inter- or intra-network “hubs” that connect and integrate segregated functional domains in the brain. Our results suggest that optimal dynamic range of neural processing in hub regions may support cognitive operations that specifically rely on the most flexible neural processing and complex cross-talk between different brain networks. Finally, we demonstrated that older adults with greater WM integrity in all major WM tracts had also greater SD_BOLD and better performance on tests of memory and fluid abilities. We conclude that SD_BOLD is a promising functional neural correlate of individual differences in cognition in healthy older adults and is supported by overall WM integrity.