Effect of variation in BDNF Val(66)Met polymorphism, smoking, and nicotine dependence on symptom severity of depressive and anxiety disorders

Correlations among nicotine dependence, health-related quality of life, and depression in current smokers: a cross-sectional study with a mediation model

Background

Although the negative impact of smoking and health-related quality of life (HRQoL) on depression has been confirmed in various studies, There has been little exploration of how HRQoL mediates the relationship between smoking and depression. The purpose of the current study was to examine the relationship between smoking and depression in the Chinese current smokers with nicotine dependence and the mediating role of HRQoL.

Methods

A cross-sectional study named "Psychology and Behavior Investigation of Chinese Residents" was conducted from July 10 to September 15, 2021 in China. Nicotine dependence, HRQoL and depression were measured by Fagerstrom Test for Nicotine Dependence (FTND), the European Five Dimensional Five Level Health scale (EQ-5D-5L) and the 9-item Patient Health Questionnaire (PHQ-9) respectively. Information on age, gender, place of residence, household registration, education level, marital status, employment status, average family monthly income, drinking frequency, living status, BMI, multiple chronic conditions were also collected. Pearson's correlation test and logistic regression analysis were conducted to explore the association between nicotine dependence, HRQoL and depression and a mediation analysis was applied to explore the mediating effect of the HRQoL on this relationship.

Results

A total of 1,381 current smokers were included in the study. The participants showed a moderate level of nicotine dependence with a mean of 1.36(SD=1.50), a relatively high level of HRQoL scores (Mean=0.94, SD=0.13), and a depression score with a mean of 6.48(SD=6.09). Approximately 22.74% (314/1,381) of the participants were considered to indicate depression. In the univariable regression model, it was found that nicotine dependence was positively associated with depression (OR:1.094, 95%CI: 1.008-1.187), while HRQoL was negatively associated with depression (OR:0.011, 95%CI: 0.004-0.033). In the multivariable regression model, HRQoL was still notably associated with depression (OR:0.008, 95%CI: 0.002-0.027), however, the positive association was not observed between nicotine dependence and depression. The Pearson's correlation test demonstrated that nicotine dependence was negatively correlated with HRQoL(rs= -0.147, P<0.001) and HRQoL was negatively correlated with depression(rs= -0.275, P<0.001). In contrast, nicotine dependence was positively correlated with depression(rs= 0.136, P<0.001). Mediation analysis found that HRQoL moderated the relationship between nicotine dependence and depression with a mediating effect of 26.49%.

Conclusions

The findings support that nicotine dependence is positively associated with depression and HRQoL is negatively associated with depression in current smokers. HRQoL mediated the relationship between nicotine dependence and depression. The well-established imperative interventions aimed at promoting smoking cessation and improving quality of life may benefit for alleviation of depression in current smokers.

Alterations in Neurotrophins in Alcohol-Addicted Patients during Alcohol Withdrawal

BACKGROUND

Alcohol use disorder (AUD) is related to mental and somatic disorders that result in alcohol withdrawal syndrome (AWS), with 30% of AWS cases leading to life-threatening delirium tremens (DTs). Currently, studies do not support using any one biomarker in DTs. Neurotrophins affect neuromodulation, playing a role in the pathogenesis of AUD, AWS, and DTs.

METHODS

This review aims to summarize experimental and clinical data related to neurotrophins and S100B in neuroplasticity, as well as neurodegeneration in the context of AUD, AWS, and DTs. This work used publications that were selected based on the protocol consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement.

RESULTS

The BDNF level could be a good candidate biomarker for relapse susceptibility, as it is significantly reduced during consumption and gradually increases during abstinence. GDNF influences AUD through its integral role in the function of dopaminergic neurons and ablates the return to alcohol-drinking behavior. NGF protects neurons from ethanol-induced cytotoxic damage and affects recovery from cognitive deficits after brain damage. The NT-3 level is decreased after alcohol exposure and is involved in compensatory mechanisms for cognitive decline in AUD. NT-4 affects oxidative stress, which is associated with chronic alcohol consumption. S100B is used as a biomarker of brain damage, with elevated levels in serum in AUD, and can protect 5-HT neurons from the damage caused by alcohol.

CONCLUSIONS

BDNF, GDNF, NT-3, NT-4, NGF, and S100B may be valuable markers for withdrawal syndrome. In particular, the most relevant is their association with the development of delirium complications. However, there are few data concerning some neurotrophins in AWS and DTs, suggesting the need for further research.

The association between BDNF C270T genetic variants and smoking in patients with mental disorders and in healthy controls

Studies investigating the association between smoking and the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism have reported inconclusive results, while the studies on the association of smoking status with BDNF C270T polymorphism are missing. We aimed to determine the association of smoking and BDNF Val66Met and C270T genetic variants in control subjects and patients with mental disorders. This study included 3502 Caucasian subjects: 918 healthy controls and 2584 patients with mental disorders (519 individuals with posttraumatic stress disorder (PTSD), 419 patients with depression, 996 patients with schizophrenia, and 650 patients with alcohol dependence). The frequency of the BDNF Val66Met and C270T variants were presented in codominant, dominant and recessive models. BDNF C270T, but not BDNF Val66Met polymorphism, was significantly associated with smoking in all groups, since the presence of the C270T T allele was more frequently found in smokers compared to non-smokers. Significant predictors of smoking were sex, age and BDNF C270T genetic variants. However, after detailed analysis of the separate diagnostic entities, the significant association of BDNF C270T polymorphism was confirmed only in healthy subjects, but not in patients with mental disorders; and was not related to number of cigarettes smoked per day. In patients with alcohol dependence, the severity of smoking was significantly associated with BDNF Val66Met variants. This is a first report of the significant association between the BDNF C270T polymorphism and smoking status in the large groups of Caucasian cases/controls.

Associations of clinical, psychological, and socioeconomic characteristics with nicotine dependence in smokers

Cigarette smoking is a risk factor of mortality and morbidity from various cancerous, respiratory, and myocardial diseases. Nicotine dependence is assessed based on the degree of physical dependence. We aimed to determine the clinical, socioeconomic and psychological factors associated with the smoking status and degree of nicotine dependence of smokers. From April 2009 to September 2010, we retrospectively collected data from 17,577 subjects aged ≥ 18 years who had undergone a general health examination at a health promotion center. The instruments used included the Fagerström Tolerance Questionnaire (FTQ), Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI), Stress Response Inventory (SRI), and Alcohol Use Disorder Identification Test (AUDIT). Of the current smokers (N = 3946), 2345 (59%), 1154 (29%), and 447 (12%) had low, moderate, and high nicotine dependence, respectively. In multiple logistic analysis, predictors of high nicotine dependence were male sex (odds ratio [OR] 3.705, 95% confidence interval [CI] 1.997–6.945), older age (≥ 65 years) (OR 1.016, 95% CI 1.004–1.029), higher body mass index (BMI) (OR 1.048, 95% CI 1.018–1.078), diabetes (OR 1.870, 95% CI 1.251–2.794), single marital status (OR 1.575, 95% CI 1.186–2.092), lower education level (OR 1.887, 95% CI 1.463–2.433), and a higher stress level (OR 1.018, 95% CI 1.997–6.945). Thus, clinical, psychological, socioeconomic status including male, older age, higher BMI, diabetes, single marital status, lower education, and higher stress should be taken into consideration by promoting smoking cessation.

The Role of Anxiety in Smoking Onset, Severity, and Cessation-Related Outcomes: a Review of Recent Literature

PURPOSE OF REVIEW

Anxiety is one of the most common mental health conditions globally and co-occurs with smoking at a markedly high rate. The present review offers a narrative overview of the most recent research on the role of anxiety in smoking onset, maintenance, and cessation-related outcomes. Additionally, given the rise in electronic cigarette use, we review the emerging literature on the influence of anxiety on e-cigarette use.

RECENT FINDINGS

Evidence across studies varied as to the role of anxiety or anxiety symptoms in smoking behavior. The most consistent findings suggested that those with anxiety are more likely to be a smoker, supporting a high rate of co-occurrence across these conditions. Less consistent evidence was observed for the association between anxiety and onset, indicators of severity, and cessation outcomes. Although there is robust evidence for an association between smoking and anxiety, there were considerable discrepancies for the precise role of anxiety in smoking onset, severity, and cessation outcomes. Future work utilizing more sophisticated methodologies is needed to identify causal relations as well as putative moderators and mediators of the anxiety-smoking relation.

Differential Association of Serum BDNF With Poststroke Depression and Poststroke Anxiety

OBJECTIVES

To investigate the correlation between brain-derived neurotrophic factor (BDNF) and risk factors, as well as functional outcome in poststroke depression (PSD) or poststroke anxiety (PSA).

DESIGN

Cohort study.

SETTING

Stroke patients admitted to an urban rehabilitation hospital.

PARTICIPANTS

Stroke patients (N=162) without any previous history of depression and anxiety.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Sociodemographic information and comorbidities were recorded during hospital admission. Functional outcomes were assessed using FIM scores at time of admission and discharge. The influence of various factors such as BDNF and patient characteristics on functional outcome was investigated. Single-factor effect was examined using simple logistic regression, as was multi-factor effect using multiple logistic regression. The goodness-of-fit of those regression models was evaluated by the integrated area under ROC curve.

RESULTS

PSD was diagnosed in 61 (37.7%) patients, and PSA was diagnosed in 40 (24.7%). Multiple logistic analysis showed that BDNF, divorce or separation, and history of smoking were significantly associated with the occurrence of PSD but not with the occurrence of PSA. The model combining low BDNF level and divorce or separation improved the prediction for PSD. Among the variables analyzed for prediction of functional outcome, serum BDNF had a minimum correlation with motor FIM scores in PSD but no significant correlation with motor FIM scores in PSA.

CONCLUSIONS

BDNF is a valuable prediction for the occurrence of PSD but not for PSA. More strikingly, ischemic stroke patients who are divorced or separated with low serum BDNF have a much higher risk for PSD. BDNF has a minimum correlation with motor function outcome in PSD but no significant correlation with motor outcome in PSA.

Association between BDNF Val66Met polymorphism and generalized anxiety disorder and clinical characteristics in a Mexican population: A case-control study

The aim of the present case-control study was to explore the association between BDNF Val66Met (rs6265) polymorphism and generalized anxiety disorder in Mexican individuals, and whether this polymorphism plays a role in the symptomatology of anxiety.A total of 212 subjects were included in the study. Around 75 patients with generalized anxiety disorder were diagnosed by psychiatrists based on the DSM-IV instrument and 137 unrelated subjects psychiatrically healthy were used as comparison group. The subclinical symptomatology in patients was assessed with the State-Trait Anxiety Inventory. BDNF rs6265 genotypes were analyzed using the polymerase chain reaction end-point method.The association between BDNF Val66Met with the risk for generalized anxiety disorder was evaluated using 4 inheritance models. The present study showed that carrying the Met allele confers increased risk for the presence of generalized anxiety disorder (χ = 4.7, P = .03; OR (95%) 1.96 (1.05-3.56)) when patients with generalized anxiety disorder were compared with the comparison group.Our results provide evidence of an association between the Val66Met polymorphism of the BDNF gene and generalized anxiety disorder in a Mexican population. However, no association was observed between this polymorphism and the symptomatology of anxiety.

Effects of smoking on cognition and BDNF levels in a male Chinese population: relationship with BDNF Val66Met polymorphism

Recent studies demonstrate that brain-derived neurotrophic factor (BDNF) might be associated with nicotine addiction, and circulating BDNF is a biomarker of memory and general cognitive function. Moreover, studies suggest that a functional polymorphism of the BDNF Val66Met may mediate hippocampal-dependent cognitive functions. We aimed to explore the relationships between smoking, cognitive performance and BDNF in a normal Chinese Han population. We recruited 628 male healthy subjects, inducing 322 smokers and 306 nonsmokers, and genotyped them the BDNF Val66Met polymorphism. Of these, we assessed 114 smokers and 98 nonsmokers on the repeatable battery for the assessment of neuropsychological status (RBANS), and 103 smokers and 89 nonsmokers on serum BDNF levels. Smokers scored lower than the nonsmokers on RBANS total score (p = 0.002), immediate memory (p = 0.003) and delayed memory (p = 0.021). BDNF levels among the smokers who were Val allele carriers were correlated with the degree of cognitive impairments, especially attention, as well as with the carbon monoxide concentrations. Our findings suggest that smoking is associated with cognitive impairment in a male Chinese Han population. The association between higher BDNF levels and cognitive impairment, mainly attention in smokers appears to be dependent on the BDNF Val66Met polymorphism.

Depressed female smokers have higher levels of soluble tumor necrosis factor receptor 1

Aim

To examine clinical and biomarkers in depressed female smokers, in order to better clarify the process that link mood disorders, childhood trauma and smoking in women.

Methods

The clinical sample comprised women with unipolar or bipolar depression, divided into subgroups of smokers and never-smoker. The control groups comprised two subgroups non-depressed women, separated into smokers and never-smokers. A structured questionnaire was used to assess socio-demographic and clinical data. The following scales were used: 17-item version Hamilton Depression Rating Scale, Hamilton Anxiety Rating scale (HAM-A), Sheehan disability scale, the Child Trauma Questionnaire. The following biomarkers were investigated: lipid profile, including total cholesterol, high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol, triglycerides the Castelli's Risk indexes I and II; and cytokines, including interleukins (IL)-1β, IL-6, IL-10, IL-12, soluble tumor necrosis factor receptor 1 (sTNF-R1).

Results

Depressed female smokers showed a number of significant positive correlations: emotional neglect and sTNF-R1 (p = 0.02); waist circumference and sTNF-R1 (p = 0.001); body mass index and sTNF-R1 (p < 0.01); HAM-A and sTNF-R1 (p = 0.03); IL-1β and sTNF-R1 (p < 0.01); IL-10 and sTNF-R1 (p = 0.001); IL-12 and sTNF-R1 (p < 0.01);Castelli index I and sTNF-R1 (p < 0.01); Castelli index II and sTNF-R1 (p < 0.01); and a significantly negative correlation between HDLc and sTNF-R1(p = 0.014).

Conclusion

This study suggests that depressed female smokers who experienced more childhood trauma and had more anxiety symptoms are associated with the activation of inflammatory processes and alterations in components of lipid profile.

BDNF Val66Met and childhood adversity on response to physical exercise and internet-based cognitive behavioural therapy in depressed Swedish adults

The genetic effect of Brain-derived neurotrophic factor (BDNF) on treatment response in depression is not consistent in the literature. Childhood adversity is a known risk factor for depression which has been reported to increase depression susceptibility by interacting with BDNF genetic variation. We aimed to explore whether the BDNF variation Val66Met and childhood adversity (CA) predicted the treatment response to a 12-week intervention with physical exercise (PE) or internet-based cognitive behavioural therapy (ICBT) when compared with treatment as usual (TAU). A prospective cohort study nested within a randomised control trial was conducted using data from 547 participants with mild to moderate depression. Depression severity at baseline and follow-up was measured using the Montgomery-Åsberg Depression Rating Scale. Met allele carriers without exposure to CA and current antidepressant use showed higher treatment response to PE than Val homozygotes. There was no evidence to support that BDNF Val66Met or CA alone predicted treatment response to PE and ICBT. The Met carriers had higher serum mature BDNF level. These data suggest that Met allele carriers benefit more from PE treatment but only if they are not exposed to early adversity.

Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism interacts with gender to influence cortisol responses to mental stress

Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism has been associated with cortisol responses to stress with gender differences reported, although the findings are not entirely consistent. To evaluate the role of Val66Met genotype and gender on cortisol responses to stress, we conducted a 45-min mental stress protocol including four tasks and four rest periods. Blood cortisol was collected for assay immediately before and after each task and rest period. A significant two-way interaction of Val66Met genotype×gender (P=0.022) was observed on the total area under the curve (AUC), a total cortisol response over time, such that the Val/Val genotype was associated with a larger cortisol response to stress as compared to the Met group in women but not in men. Further contrast analyses between the Val/Val and Met group for each stress task showed a similar increased cortisol pattern among women Val/Val genotype but not among men. The present findings indicate the gender differences in the effect of Val66Met genotype on the cortisol responses to stress protocol, and extend the evidence for the importance of gender and the role of Val66Met in the modulation of stress reactivity and subsequent depression prevalence. Further studies and the underlying mechanism need to be investigated, which may provide an insight for prevention, intervention, and treatment strategies that target those at high risk.

BDNF Val66Met Polymorphism as a Moderator of Exercise Enhancement of Smoking Cessation Treatment in Anxiety Vulnerable Adults

BACKGROUND

Exercise interventions facilitate odds of quit success among high-anxiety sensitive adults smokers. We examined the dependency of these benefits on the genetic BDNF Val66Met (rs6265) polymorphism; individuals who are Met carriers have lower BDNF responses and reduced associated benefits from exercise. Accordingly, we hypothesized that the efficacy of vigorous exercise for smoking cessation would be specific to high-anxiety sensitive Val/Val carriers.

METHODS

Participants were adults (N=55) of European ancestry who had participated in a randomized controlled trial comparing a smoking cessation program augmented with exercise vs. augmented with a wellness control treatment. In this secondary analysis, growth curve models for point-prevalence abstinence (PPA) and prolonged abstinence (PA) employed for the main outcome analyses were amended to test the moderator effects of the BDNF Val66Met polymorphism.

RESULTS

Consistent with prediction, the advantage of exercise over control for PPA was significantly greater among high-anxiety sensitive persons with the Val/Val genotype than for those with the Val/Met genotype. This advantage did not reach statistical significance for PA. Differences in abstinence between the exercise and control interventions among low-anxiety sensitive smokers were not dependent on the BDNF Val66Met polymorphism.

CONCLUSIONS

We found that the efficacy of exercise for augmenting smoking cessation treatment is intensified among high-anxiety sensitive smokers who are Val/Val carriers. This observation is consistent with findings documenting BDNF mediation of exercise benefits and greater negative affect among smokers who are Val/Val carriers. These data encourage further evaluation of the association between the BDNF polymorphism, exercise, anxiety sensitivity, and smoking cessation.

Prenatal and Early Postnatal Exposure to Cigarette Smoke Decreases BDNF/TrkB Signaling and Increases Abnormal Behaviors Later in Life

BACKGROUND

Cigarette smoke exposure during prenatal and early postnatal periods increases the incidence of a variety of abnormal behaviors later in life. The purpose of this study was to identify the possible critical period of susceptibility to cigarette smoke exposure and evaluate the possibe effects of cigarette smoke during early life on brain-derived neurotrophic factor/neurotrophic tyrosine kinase receptor B signaling in the brain.

METHODS

Three different age of imprinting control region mice were exposed to cigarette smoke or filtered air for 10 consecutive days beginning on either gestational day 7 by maternal exposure, or postnatal days 2 or 21 by direct inhalation. A series of behavioral profiles and neurotrophins in brain were measured 24 hours after mice received acute restraint stress for 1 hour on postnatal day 59.

RESULTS

Cigarette smoke exposure in gestational day 7 and postnatal day 2 produced depression-like behaviors as evidenced by significantly increased immobility in both tail suspension and forced-swim test. Increased entry latencies, but not ambulation in the open field test, were also observed in the gestational day 7 and postnatal day 2 cigarette smoke exposure groups. Genetic analysis showed that gestational day 7 cigarette smoke exposure significantly altered mRNA level of brain-derived neurotrophic factor/tyrosine kinase receptor B in the hippocampus. However, behavioral profiles and brain-derived neurotrophic factor/tyrosine kinase receptor B signaling were not significantly changed in PND21 cigarette smoke exposure group compared with FA group.

CONCLUSIONS

These results suggest that a critical period of susceptibility to cigarette smoke exposure exists in the prenatal and early postnatal period, which results a downregulation in brain-derived neurotrophic factor/tyrosine kinase receptor B signaling in the hippocampus and enhances depression-like behaviors later in life.