Impulsivity and midlife cardiometabolic risk: The role of maladaptive health behaviors

Faecal microbiota composition and impulsivity in a cohort of older adults with metabolic syndrome

Impulsivity is an important determinant of human behaviour, affecting self-control, reasonable thinking and food choices. Recent evidence suggests a role for gut microbiota in human behaviour, but the relationship between gut microbiota and impulsive behaviours remains largely unexplored. To address this knowledge gap, the present study aims to explore the associations between faecal microbiota composition with trait and behavioural impulsivity, in a subcohort of the PREDIMED-Plus trial, including older adults presenting overweight/obesity. Fecal samples (n = 231) were profiled for their microbiota composition using 16 S rRNA amplicon sequencing and impulsivity was determined through four different assessments. Adherence to different dietary patterns was estimated through questionnaires. Beta diversity analyses showed a significant association with the Conner's Performance Test (CPT) in multivariate-adjusted models, and, in total, 13 bacterial genera associated with CPT. Erysipelotrichaceae UCG 003 showed the highest association with CPT and known butyrate producers such as Butyricicoccus spp., Roseburia spp., and Eubacterium hallii were among the identified bacteria. The bacteria Lachnospiraceae UCG 001, Anaerostipes and Blautia were associated with CPT and also the adherence to healthy and unhealthy plant-based diets. In addition, functional analysis showed a significant negative association between the CPT and the glucuronate and galacturonate metabolic pathways. From the other impulsivity assessments, two more associations were identified, for the genus Phascolarctobacterium with the Stroop test, and the genus Lachnospiraceae GAG 54 with the positive urgency subscore of UPPS-P Impulsive Behaviour Scale. Overall, our findings suggest potential links between the faecal microbiota composition and function with behavioural impulsive inattention as determined by the CPT.

Glycated hemoglobin, type 2 diabetes, and poor diabetes control are positively associated with impulsivity changes in aged individuals with overweight or obesity and metabolic syndrome

Impulsivity has been proposed to have an impact on glycemic dysregulation. However, it remains uncertain whether an unfavorable glycemic status could also contribute to an increase in impulsivity levels. This study aims to analyze associations of baseline and time-varying glycemic status with 3-year time-varying impulsivity in older adults at high risk of cardiovascular disease. A 3-year prospective cohort design was conducted within the PREDIMED-Plus-Cognition substudy. The total population includes 487 participants (mean age = 65.2 years; female = 50.5%) with overweight or obesity and metabolic syndrome. Insulin resistance (HOMA-IR), glycated hemoglobin (HbA1c), presence of type 2 diabetes mellitus, and type 2 diabetes control were evaluated. Impulsivity was measured using the Impulsive Behavior Scale questionnaire and various cognitive measurements. Impulsivity z-scores were generated to obtain Global, Trait, and Behavioral Impulsivity domains. Linear mixed models were used to study the longitudinal associations across baseline, 1-year, and 3-year follow-up visits. HOMA-IR was not significantly related to impulsivity. Participants with higher HbA1c levels, type 2 diabetes, and poor control of diabetes showed positive associations with the Global Impulsivity domain over time, and those with higher HbA1c levels were further related to increases in the Trait and Behavioral Impulsivity domains over the follow-up visits. These results suggest a potential positive feedback loop between impulsivity and glycemic-related dysregulation.

Trait impulsivity is associated with an increased risk of type 2 diabetes incidence in adults over 8 years of follow-up: results from the NutriNet-Santé cohort

BACKGROUND

Type 2 diabetes is one of the most prevalent and preventable diseases worldwide and impulsivity, a psychological trait characterized by making quick decisions without forethought, has been suggested as a key feature for health-related conditions. However, there have been no studies examining the relationships between impulsivity and the incidence of type 2 diabetes and our aim was to assess the prospective association between trait impulsivity and the risk of developing type 2 diabetes.

METHODS

A prospective observational study design was conducted between May 2014 and February 2023 within the NutriNet-Santé cohort. A web-based platform was used to collect data from the French adult population, with voluntary enrollment and participation. Of the 157,591 adults (≥ 18 years old) participating in the NutriNet-Santé study when impulsivity was assessed, 109,214 participants were excluded due to prevalent type 1 or 2 diabetes or missing data for impulsivity or follow-up data for type 2 diabetes. Trait impulsivity, and the attention, motor, and non-planning subfactors, were assessed at baseline using the Barratt Impulsiveness Scale 11. Incident type 2 diabetes was ascertained through follow-up. Medical information was reviewed by NutriNet-Santé physician experts to ascertain incident diabetes cases based on the ICD-10. Cox regression models, using hazard ratios and 95% confidence intervals (HR [95% CI]), were performed to evaluate associations between impulsivity per 1 standard deviation increment and type 2 diabetes risk, adjusting by recognized confounders.

RESULTS

Of the 48,377 individuals studied (women 77.6%; age at baseline = 50.6 year ± 14.5 years), 556 individuals developed type 2 diabetes over a median follow-up of 7.78 (IQR: 3.97-8.49) years. Baseline impulsivity was associated with an increased risk of type 2 diabetes incidence (HR = 1.10 [1.02, 1.20]). The motor impulsivity subfactor was positively associated with type 2 diabetes risk (HR = 1.14 [1.04, 1.24]), whereas no associations were found for attention and non-planning impulsivity subfactors.

CONCLUSIONS

Trait impulsivity was associated with an increased type 2 diabetes risk, mainly driven by the motor impulsivity subfactor. If these results are replicated in other populations and settings, trait impulsivity may become an important psychological risk factor to be considered in the prevention of type 2 diabetes.

COHORT REGISTRATION

Name of registry: The NutriNet-Santé Study. A Web-based Prospective Cohort Study of the Relationship Between Nutrition and Health and of Dietary Patterns and Nutritional Status Predictors. Cohort registration number: NCT03335644. Date of registration: October 11, 2017. URL: https://clinicaltrials.gov/ct2/show/NCT03335644.

The Iowa Gambling Task: Men and Women Perform Differently. A Meta-analysis

The Iowa Gambling Task (IGT) was designed to assess decision-making under conditions of complexity and uncertainty; it is currently one of the most widely used tests to assess decision-making in both experimental and clinical settings. In the original version of the task, participants are given a loan of play money and four decks of cards and are asked to maximize profits. Although any single card unpredictably yields wins/losses, variations in frequency and size of gains/losses ultimately make two decks more advantageous in the long term. Several studies have previously suggested that there may be a sex-related difference in IGT performance. Thus, the present study aimed to explore and quantify sex differences in IGT performance by pooling the results of 110 studies. The meta-analysis revealed that males tend to perform better than females on the classic 100-trial IGT (UMD = 3.381; p < 0.001). Furthermore, the significant heterogeneity observed suggests high variability in the results obtained by individual studies. Results were not affected by publication bias or other moderators. Factors that may contribute to differences in male and female performance are discussed, such as functional sex-related asymmetries in the ventromedial prefrontal cortex and amygdala, as well as differences in sensitivity to wins/losses.

Are sick people really more impulsive?: Investigating inflammation-driven impulsivity

In both animals and humans, inflammatory stimuli - especially infections and endotoxin injections - cause "sickness behaviors," including lethargy, malaise, and low mood. An emerging line of research asserts that inflammation may provoke present-focused decision making and impulsivity. The current article assesses that claim in the context of the broader literature - including preclinical models and clinical interventions. This literature presents three challenges to purported inflammation-impulsivity link that have not been addressed to date: (1) the nebulous and imprecise definition of impulsivity; (2) reverse causality; and (3) a lack of causal evidence. These challenges point to ways in which future research designs can improve upon the extant literature to further explore the ostensible relationship between inflammation and impulsivity.

Negative urgency and central adiposity in a community sample: Moderated mediation by depressive symptoms and eating behaviors

Negative urgency - acting rashly in response to negative emotions - is a risk factor for central adiposity. We examine whether the relationship between negative urgency and waist-to-height ratio (WHtR) is mediated by eating behaviors (emotional eating, external eating, and cognitive restraint) and moderated by depressive symptom severity, factors that could be targeted to reduce risk associated with negative urgency. Using baseline data from the Nathan Kline Institute-Rockland Sample (N = 872; mean age = 42.4 years, SD = 15.3; 65% female; 27% non-White; mean body mass index = 27.9 kg/m², SD = 5.9), we conducted a series of mediation and moderated mediation analyses controlling for age, sex, race, and socioeconomic status. Overall, there was a positive association between negative urgency and WHtR. Emotional eating (ab = 0.02, SE = 0.003, 95% CI [0.02, 0.03]) and uncontrolled eating (ab = 0.008, SE = 0.002, 95% CI [0.004, 0.01]) were partial mediators of the relationship between negative urgency and WHtR, while cognitive restraint was not. In a parallel mediation model, emotional eating remained significant, while uncontrolled eating did not. Depressive symptom severity moderated the indirect effect of negative urgency on WHtR through emotional eating (b_int = -0.08, p < .001) but not the direct effect of negative urgency on WHtR. Our results indicate that emotional eating is a viable potential mechanism explaining the relationship between negative urgency and WHtR, and the indirect effect of negative urgency on WHtR through emotional eating becomes stronger as depressive symptom severity decreases.