Behavioural studies in humans: anxiety, stress and smoking

Does combined training of biofeedback and neurofeedback affect smoking status, behavior, and longitudinal brain plasticity?

Introduction: Investigations of biofeedback (BF) and neurofeedback (NF) training for nicotine addiction have been long documented to lead to positive gains in smoking status, behavior and to changes in brain activity. We aimed to: (a) evaluate a multi-visit combined BF/NF intervention as an alternative smoking cessation approach, (b) validate training-induced feedback learning, and (c) document effects on resting-state functional connectivity networks (rsFCN); considering gender and degree of nicotine dependence in a longitudinal design. Methods: We analyzed clinical, behavioral, and electrophysiological data from 17 smokers who completed five BF and 20 NF sessions and three evaluation stages. Possible neuroplastic effects were explored comparing whole-brain rsFCN by phase-lag index (PLI) for different brain rhythms. PLI connections with significant change across time were investigated according to different resting-state networks (RSNs). Results: Improvements in smoking status were observed as exhaled carbon monoxide levels, Total Oxidative Stress, and Fageström scores decreased while Vitamin E levels increased across time. BF/NF promoted gains in anxiety, self-esteem, and several aspects of cognitive performance. BF learning in temperature enhancement was observed within sessions. NF learning in theta/alpha ratio increase was achieved across baselines and within sessions. PLI network connections significantly changed across time mainly between or within visual, default mode and frontoparietal networks in theta and alpha rhythms, while beta band RSNs mostly changed significantly after BF sessions. Discussion: Combined BF/NF training positively affects the clinical and behavioral status of smokers, displays benefit in smoking harm reduction, plays a neuroprotective role, leads to learning effects and to positive reorganization of RSNs across time. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT02991781.

Changes in cigarette consumption and intention to quit in response to the COVID-19 pandemic in China

INTRODUCTION

Significant changes occurred in the way people socialize and interact with each other since China reported its first COVID-19 cases. However, little is known about how smoking behaviors may have changed due to the COVID-19 pandemic in China. The aim of this study was to assess changes in smoking behavior and intention to quit during the early stage of the COVID-19 pandemic in China and to investigate the associated factors.

METHODS

An online cross-sectional survey was conducted among Chinese adult smokers. Participants were recruited through snowball sampling from 19 March to 2 April 2020.

RESULTS

A total of 1388 smokers participated in this study. Of those, 1014 (73.0%) reported not changing their cigarette consumption, 104 (7.5%) reported smoking more and 268 (19.3%) reported smoking less due to the pandemic. Average daily cigarette consumption among all participants decreased from 15.0 (IQR: 10.0-20.0) to 13.0 (IQR: 8.0-20.0) (W=6.919, p<0.001). For intention to quit, 270 (19.5%) respondents reported becoming more willing to quit, and 91 (6.6%) reported becoming less willing to quit. Multivariate analyses showed that tobacco addiction, overall knowledge about the relationship between smoking and COVID-19, level of attention devoted to COVID-19, anxiety, living alone, and number of smokers in the family were significantly correlated with cigarette consumption and intention to quit, and living alone was the strongest factor associated with increased cigarette consumption (AOR=5.29; 95% CI: 1.51-18.56).

CONCLUSIONS

The COVID-19 pandemic led to a slight decrease in cigarette consumption and an increase in quitting intention among Chinese smokers. During the early stages of the pandemic, it was important to focus on the anxiety of smokers, dispel smokers' misunderstandings of smoking and COVID-19 and create a supporting environment in the family to help smokers quit.

Prevalence of anxiety and depressive symptoms and related risk factors among physicians in China: a cross-sectional study

BACKGROUND

Physicians' poor mental health not only hinders their professional performance and affects the quality of healthcare provided but also adversely affects patients' health outcomes. Few studies in China have evaluated the mental health of physicians. The purposes of this study are to quantify Chinese physicians' anxiety and depressive symptoms as well as evaluate associated risk factors.

METHODS

In our study, 2641 physicians working in public hospitals in Shenzhen in southern China were recruited and interviewed by using a structured questionnaire along with validated scales testing anxiety and depressive symptoms. Multivariable logistic regression models were used to identify risk factors for anxiety and depressive symptoms.

RESULTS

An estimated 25.67% of physicians had anxiety symptoms, 28.13% had depressive symptoms, and 19.01% had both anxiety and depressive symptoms. More than 10% of the participants often experienced workplace violence and 63.17% sometimes encountered it. Among our study population, anxiety and depressive symptoms were associated with poor self-reported physical health, frequent workplace violence, lengthy working hours (more than 60 hours a week), frequent night shifts (twice or more per week), and lack of regular physical exercise.

CONCLUSIONS

Our study demonstrates that anxiety and depressive symptoms are common among physicians in China, and the doctor-patient relationship issue is particularly stressful. Interventions implemented to minimize workload, improve doctor-patient relationships, and assist physicians in developing healthier lifestyles are essential to combat anxiety and depressive symptoms among physicians, which may improve their professional performance.

Nicotine-induced plasma corticosterone is attenuated by social interactions in male and female adolescent rats

Most smokers begin smoking during adolescence, a period during which social reward is highly influential. Initial exposure to nicotine can produce anxiogenic effects that may be influenced by social context. This study examined play behavior and plasma corticosterone following nicotine administration (0.6 mg/kg, s.c.) in both male and female adolescent (PND39) Sprague-Dawley rats in either isolate or social contexts. In blood samples collected immediately following the 15-min test session, nicotine increased plasma corticosterone relative to saline in both male and female isolate rats, but failed to do so in both males and females placed together in same-sex pairs. Nicotine also attenuated several indices of play behavior including nape attacks, pins and social contact. In isolate rats, nicotine selectively increased locomotor activity in females; however, when administered to social pairs, nicotine decreased locomotion in both sexes. These findings suggest that the presence of a social partner may decrease the initial negative, stress-activating effects of nicotine, perhaps leading to increased nicotine reward.

Prosocial effects of nicotine and ethanol in adolescent rats through partially dissociable neurobehavioral mechanisms

The widespread use of tobacco and alcohol among adolescents might be related to the ability of nicotine and ethanol to facilitate social interactions. To investigate the neurobehavioral mechanisms underlying the prosocial effects of nicotine and ethanol, we focused on social play behavior, the most characteristic social activity in adolescent rats. Social play behavior is rewarding, and it is modulated through opioid, cannabinoid and dopaminergic neurotransmission, which are also involved in the reinforcing properties of nicotine and ethanol. We found that nicotine and ethanol increased social play, without affecting locomotion or social exploration. Their effects depended on the level of social activity of the partner, and were comparable in familiar and unfamiliar environments. At doses that increased social play, nicotine and ethanol had no anxiolytic effects in the elevated plus-maze. By contrast, the prototypical anxiolytic drug diazepam reduced social play at doses that reduced anxiety. The effects of nicotine on social play were blocked by the opioid receptor antagonist naloxone, the CB(1) cannabinoid receptor antagonist SR141716A, and the dopamine receptor antagonist alpha-flupenthixol. The effects of ethanol were blocked by SR141716A and alpha-flupenthixol, but not by naloxone. Combined administration of subeffective doses of nicotine and ethanol only modestly enhanced social play. These results show that the facilitatory effects of nicotine and ethanol on social play are behaviorally specific and mediated through neurotransmitter systems involved in positive emotions and motivation, through partially dissociable mechanisms. Furthermore, the stimulating effects of nicotine and ethanol on social play behavior are independent of their anxiolytic-like properties.