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Parental recall, attachment relating and self-attacking/self-reassurance: their relationship with depression.

OBJECTIVES: When things go wrong for people they can become self-critical or focus on positive, reassuring aspects of the self. This study explored the relationship between forms of self-criticism and self-reassurance, recall of parental experiences and attachment style in relation to depressed symptoms in students. METHODS: A sample of 197 undergraduate students from the UK and Canada completed self-report questionnaires measuring recall of parental styles, attachment, forms of self-criticism, self-reassurance, and depression symptoms. RESULTS: Recall of parents as rejecting and overprotecting was significantly related to both inadequacy and self-hating self-criticism. In contrast, parental warmth was negatively correlated with these forms of self-criticism. In addition, when things go wrong for the person, recall of parental warmth was associated with the ability to be self-reassuring. A mediator analysis suggested that (I) the impact of recall of negative parenting on depression is mediated through the forms of self-criticism and (2) the effect of parental warmth on depression was mediated by the ability to be self-reassuring. CONCLUSIONS: The impacts of negative parenting styles may translate into vulnerabilities to depression via the way children (and later adults) develop their self-to-self relating (e.g. as self-critical versus self-reassuring). Hence, there is a need for further research on the link between attachment experiences, recall of parental rejection/warmth and their relationship to internal, self-evaluative and affect systems in creating vulnerabilities to psychopathology.

Adult↗

Parental drinking as a risk factor for children's maladjustment: the mediating role of family environment.

In the present study, the relationships among parental drinking, family environment, and child adjustment is investigated in a community sample of 207 10-14-year-olds. Multiple aspects of perceived family environment (e.g., cohesion, organization, conflict) as well as multiple indicators of adjustment (e.g., negative affect, feelings of competence, self-esteem) are taken into consideration. Parental alcohol problems are found to be associated with low family cohesion, poor family organization, and low global self-worth of the child. A mediational analysis reveals that the relation between parental drinking and low global self-worth is mediated by family cohesion.

Adjustment Disorders↗

Criticizing and reassuring oneself: An exploration of forms, styles and reasons in female students.

OBJECTIVES: Self-critical people, compared with those who self-reassure, are at increased risk of psychopathology. However, there has been little work on the different forms and functions of these self-experiences. This study developed two self-report scales to measure forms and functions of self-criticism and self-reassurance and explore their relationship to depression. METHODS: A self-report scale measuring forms of self-criticism and self-reassuring, and a scale measuring possible functions of self-criticism, together with a measure of depression and another self-criticism scale (LOSC), were given to 246 female students. RESULTS: Self-criticizing vs. self-reassuring separated into two components. Forms of self-criticizing separated into two components related to: being self-critical, dwelling on mistakes and sense of inadequacy; and a second component of wanting to hurt the self and feeling self-disgust/hate. The reasons/functions for self-criticism separated into two components. One was related to desires to try to self-improve (called self-improving/correction), and the other to take revenge on, harm or hurt the self for failures (called self-harming/persecuting). Mediation analysis suggested that wanting to harm the self may be particularly pathogenic and is positively mediated by the effects of hating the self and negatively mediated by being able to self-reassure and focus on one's positives. CONCLUSIONS: Self-criticism is not a single process but has different forms, functions, and underpinning emotions. This indicates a need for more detailed research into the variations of self-criticism and the mechanisms for developing self-reassurance.

Adult↗

Contrasting mediating variables in two 5-a-day nutrition intervention programs.

BACKGROUND: Researchers have advocated mediational analysis for behavioral intervention studies to link the supporting theory used in an intervention with the mediating variables and with its ultimate success or failure. Few mediational analyses have been reported for school-based nutrition studies. The conduct of mediational analyses within multi-site studies may provide advantages for the standardization of methods and for the replication and generalizability of findings. METHODS: This study identified mediators of two school-based nutrition interventions for 4th graders. Three variables were tested on the four criteria necessary to establish mediation of intervention effects on changes in fruit and vegetable consumption (FVC) in 4th graders (Alabama, N = 1584; Minnesota, N = 522). FVC was measured in children using 24-h dietary recalls. Mediators were assessed using questionnaires completed by children and parents. RESULTS: All criteria were met in Alabama for a single-item measure of knowledge of the 5-a-day daily consumption guideline. Knowledge and parent consumption satisfied one criterion in Minnesota. Knowledge accounted for 9.78% of the total intervention effect in Alabama. CONCLUSIONS: Knowledge of the 5-a-day guideline for fruit and vegetable consumption may mediate intervention effects. Future work should include tests of mediational models in multi-site studies.

Alabama↗

Mechanisms of action in youth psychotherapy.

BACKGROUND: In this review, we address a basic, but unanswered, question about psychosocial interventions for youth: How does psychotherapy work? METHODS: We propose a framework for using mediation analysis to answer this question, and we review the youth therapy outcome literature for evidence on mediating mechanisms. We focus our review on clinical trials of empirically supported treatments for youth anxiety, depression, and disruptive behavior (N = 67). RESULTS: Contrary to previous reports indicating that potential mediators are rarely assessed, 63% of the studies included measures of potential mediating mechanisms in their designs. Across treatment domains, percentages ranged from 22% of the studies of learning-based interventions for anxiety (i.e., systematic desensitization, modeling, and reinforced practice) to 91% of parent training investigations. Despite the rather extensive assessment of potential mediators, only six studies included any attempt to use the measures in a formal mediation test. Thus, despite the positive effects of treatments and surprisingly ample assessment of mediators, we still know remarkably little about how youth psychotherapies work. CONCLUSIONS: We note common problems that hampered mediation testing (e.g., the design of many trials made it difficult to determine the temporal order of change in the mechanism and outcome), and we offer recommendations for improving study design to better assess mechanisms of therapeutic action. We also note the need to test mediation among referred youth treated in representative practice settings to complement the laboratory-based evidence on therapy mechanisms that prevails to date.

Adolescent↗

Grandparent-grandchild contact and attitudes toward older adults: moderator and mediator effects.

Two studies tested the intergroup contact hypothesis in the context of the grandparent-grandchild relationship. The hypothesis suggests that contact with an out-group member has more influence on attitudes toward the out-group when group memberships are salient. In Study 1, the predicted link was found but only for grandparents with whom the grandchild had more frequent contact. The second study examined only the most frequent grandparent relationship and replicated the effect. This study also investigated the role of various mediators of the link between quality of contact and attitudes, as well as quality of contact and perceived out-group variability. Perspective taking, anxiety, and accommodation mediated the effects of contact on attitudes, whereas individuation and self-disclosure mediated the effects of contact on perceived out-group variability. Moderated mediational analysis indicated that the moderating effect of group salience occurs between quality of contact and the mediator, not between the mediator and attitudes.

Adult↗

Does self-consciousness mediate the relation between self-talk and self-knowledge?

Building on Morin's understanding of the relations among self-talk, self-consciousness, and self-knowledge, this study examined the hypothesis that functional and dysfunctional self-consciousness mediate between self-talk and self-knowledge. A self-report questionnaire including 10 scales assessing different aspects of Self-talk, Self-consciousness, and Self-knowledge was administered to 200 German undergraduate university students (95 women, 105 men). Mediation analysis showed that the observed negative relationship between Self-talk and Self-knowledge was mediated by Dysfunctional Self-consciousness, while Functional Self-consciousness acted like a supressor variable. The discussion focuses on limitations of the present measures of Self-talk.

Adolescent↗

Two-sample Mendelian randomization study of gut microbiota and inflammatory proteins: Predictive, preventive, and personalized treatment for migraine.

The human gut microbiota is increasingly recognized as a significant factor in the pathogenesis of migraine, potentially via inflammatory pathways. Identifying specific human gut microbiota components associated with migraines, along with the investigation of particular inflammatory proteins, is essential for advancing primary prediction, targeted prevention, and personalized treatment strategies for migraines. We conducted a two-sample Mendelian randomization study using publicly available summary statistics from genome-wide association studies. Data for 473 human gut microbiota taxa were obtained from the Finnish national health survey conducted by the National Institute for Health and Welfare study (FINRISK, n = 5959 European participants). Genome-wide association study data (https://www.ebi.ac.uk/gwas/) for 91 circulating inflammatory proteins were obtained from 14,824 participants across 11 cohorts using the Olink Target 96 Inflammation panel. Migraine outcome data were obtained from the FinnGen R12 release, with cases defined using ICD-10 code G43. All genome-wide association study analyses were adjusted for sex, age, genotyping batch, and 10 genetic principal components to control population stratification (genomic inflation factors: 1.00–1.05). Inverse variance-weighted Mendelian randomization was the primary analysis method, with Mendelian randomization-Egger, weighted median, and mode-based methods as sensitivity analyses. Two-step Mendelian randomization mediation analysis quantified the proportion of the effects of human gut microbiota on migraine that are mediated through inflammatory proteins. Thirty-seven bacterial genera were found to be associated with migraine using the inverse variance-weighted method. Of these, 18 genera exhibited a negative association, while 19 genera demonstrated a positive association with migraine risk. Additionally, eight inflammatory proteins were found to increase the risk of migraine. Among human gut microbiota, four were observed to reduce inflammatory protein levels, whereas another four were associated with increased inflammatory protein levels. Additionally, five gut microbiota were identified to influence migraine through inflammatory proteins in both Mendelian randomization analyses. Specifically, Actinobacteria, Brachyspiraceae, CAG-269 sp001915995, and Paraglaciecola were found to affect migraine outcomes via inflammatory proteins, with mediation proportions of 12%, 19%, 15.5%, and 6.7%, respectively. Lawsonibacter sp002161175 was identified to influence migraine risk through Oncostatin-M and SLAM, with mediation proportions of 15.6% and 11.3%, respectively. Our study elucidated the role of specific human gut microbiota alterations in the pathogenesis of migraine and highlighted the mediating effects of inflammatory proteins. Targeting these particular human gut microbiota alterations offers a promising strategy for predictive, preventive, and personalized medicine in migraine management, resulting in substantial clinical advancements.

causality↗

Reliance on others for food-related activities of daily living.

Reliance on others for help with food-related activities (grocery shopping and meal preparation) [FADL] can influence food intake and can be considered part of the concept of food security for older adults. Data collected from 193 community-living seniors identified that 29.5% of these seniors required help with these activities. Covariates independently associated with FADL were: muscle strength/size, gender, avoidance of activities due to a fear of falling and occurrence of functionally limiting diagnoses. Mediation analysis identified variables that explain the "how and why" of the association between FADL and food intake. Mediators included informal supports, frequency of informal support, perceived health status, and number of medications. By specifically analyzing covariates and mediators of reliance for FADL, there is further understanding of the relationship between this reliance and food intake in older adults.

Activities of Daily Living↗

Perceptions of psychosis, coping, appraisals, and psychological distress in the relatives of patients with schizophrenia: an exploration using self-regulation theory.

OBJECTIVE: Following Leventhal's self-regulation model, the purpose of the present study was to provide an examination of the relationship between psychosis perceptions, coping strategies, appraisals, and distress in the relatives of patients with schizophrenia. DESIGN: Cross-sectional study. METHOD: Participants were 42 relatives of patients with schizophrenia who completed the Hospital Anxiety and Depression Scale (HADS), a brief coping strategies measure (COPE), the Revised Illness Perception Questionnaire (IPQR), and a measure of primary and secondary appraisals (Family Questionnaire). RESULTS: In general, carers who viewed their relative's psychosis as chronic, who had a stronger illness identity (experience of symptoms), who held a stronger belief in the severity of its consequences, and who reported weaker beliefs in treatment control but stronger beliefs that their relative could exert control over their condition had higher distress scores. Coping through seeking emotional support, the use of religion/spirituality, active coping, acceptance, and positive reframing were associated with less distress, while coping through self-blame was associated with higher distress scores. Hierarchical regression demonstrated that illness perceptions and coping (acceptance, positive reframing, and self-blame), respectively, made significant additional contributions to the variance in distress when entered after demographics, and primary and secondary appraisals. Furthermore, a mediational analysis suggested that coping strategies characterized by greater positive reframing, less self-blame, and greater acceptance mediated the relationship between distress, and both illness identity and carer's beliefs about how much personal control the patient could exercise over their condition. There was no mediational effect of coping on the relationship between distress and carers' perceptions about symptom control through medical treatment. CONCLUSION: Results provide partial but not unequivocal support for the self-regulation model in the current sample. Findings may invite us to consider the further use of the self-regulation/common sense model as a framework for understanding distress in the carers of people with a diagnosis of schizophrenia.

Adaptation, Psychological↗

Mutability and propensity in causal selection.

We examined differences in causal ratings of 1 factor depending on the mutability (defined as the ease with which a factor can be imagined to be different) and causal propensity (defined as the likelihood that the event would occur in the presence of a factor) of another factor that conjoined to produce the event. In 3 studies, causal ratings of the target factor depended on the interaction of mutability and propensity of the other factor. When the other factor was high in mutability, ratings of the target decreased as the propensity of the contributing factor increased, but when the other was low in mutability, ratings of the target increased as the propensity of the contributing factor increased. Mediation analysis indicated that mutability and propensity affected causal ratings by determining the comparison against which the event was considered. Comparison judgments also mediated beliefs about which factor should have adjusted to the other.

Adult↗

Development of a new reference standard for microarray experiments.

Often microarray studies require a reference to indirectly compare the samples under observation. References based on pooled RNA from different cell lines have already been described (here referred to as RNA-R), but they usually do not exhaustively represent the set of genes printed on a chip, thus requiring many adjustments during the analyses. A reference could also be generated in vitro transcribing the collection of cDNA clones printed on the microarray in use (here referred to as T3-R). Here we describe an alternative and simpler PCR-based methodology to construct a similar reference (Chip-R), and we extensively test and compare it to both RNA-R and T3-R. The use of both Chip-R and T3-R dramatically increases the number of signals on the slides and gives more reproducible results than RNA-R. Each reference preparation is also evaluated in a simple microarray experiment comparing two different RNA populations. Our results show that the introduction of a reference always interferes with the analysis. Indeed, the direct comparison is able to identify more up- or down-regulated genes than any reference-mediated analysis. However, if a reference has to be used, Chip-R and T3-R are able to guarantee more reliable results than RNA-R.

Calibration↗

Integrative oral and gut microbiome profiling highlights microbial correlates of complications in type 1 diabetes: a cross-sectional analysis.

BACKGROUND/OBJECTIVE: Chronic vascular complications are the primary threat in long-standing type 1 diabetes (T1D) patients. We examined the associations between oral-gut microbiome dysbiosis and these complications, offering novel insights into therapeutic strategies and underlying mechanisms. METHODS: This cross-sectional study enrolled 75 T1D participants (disease duration ≥ 10 years) and 43 healthy controls who underwent comprehensive clinical assessment, including blood glucose, lipid profile, and complication-related examinations. Fecal and oral rinse samples were collected for shotgun metagenomic sequencing. T1D participants were stratified by the presence of microvascular (retinopathy, nephropathy, or neuropathy) or macrovascular complications separately. Microbial differences across groups were assessed. RESULTS: Significant differences in oral and gut microbiota compositions were observed between T1D participants with and without complications (both microvascular and macrovascular). A core set of 26 gut and 8 oral microbial species was specifically associated with vascular complications. Butyrate-producing gut bacteria (Blautia wexlerae, Anaerobutyricum hallii, Roseburia inulinivorans, A. soehngenii) and specific oral Neisseria species were enriched in T1D without complications individuals, suggesting protective effects against complications. Mediation analysis indicated associations consistent with partial mediation between certain microbial species and the relationships of glycemic control or insulin resistance (HbA1c, glucose risk index, estimated glucose disposal rate) with complication risk. Moreover, potential oral-gut microbiome interconnections were implicated in complication development. Finally, classification models integrating both oral and gut microbial features significantly outperformed models based on either site alone in distinguishing T1D patients with complications. CONCLUSIONS: Distinct oral and gut microbiome features are associated with chronic vascular complications in T1D. These findings highlight the potential of microbiome-targeted strategies for understanding and preventing T1D-related complications.

Humans↗

When acculturation hurts: the case of immunization.

The study examined the relationship between the acculturation of Mexican American mothers in Texas and immunization status of their children between 3 and 24 months of age. Mothers' acculturation, demographic characteristics, and immunization status of their children were assessed in in-person interviews with a sample of Mexican American respondents representative for Texas (n = 2193). Acculturation was measured with ten scales assessing oral and written language use, proficiency, and preference, music and TV viewing preferences, ethnic identity, place where a person was reared, and contacts with Mexico. Immunization status, defined according to the recommendation of the CDC Advisory Committee on Immunization Practices, was determined from official shot records obtained directly from respondents or, for respondents without records, obtained from their health care providers. Regression analysis revealed that acculturation significantly contributed to inadequate immunization status, even when socioeconomic status and other demographic covariates of acculturation were statistically controlled. Mediational analysis revealed that acculturation contributed to inadequate immunization through less positive attitudes toward immunization, a diminished sense of parental responsibility for children's immunization, and more perceived barriers to immunization. It is concluded that culture-specific beliefs encouraging childhood immunization should be fostered among Mexican Americans.

Acculturation↗

Trait understanding or evaluative reasoning? An analysis of children's behavioral predictions.

This study tested the hypothesis that in predicting the future behavior of an actor, older children rely on trait inferences, whereas younger children rely on global, evaluative inferences. Vignettes depicting actors engaging in trait-relevant behaviors were presented to 5- and 6-year-olds (N = 67) and 9- and 10-year-olds (N = 71). For each actor, children made predictions of future behavior, evaluated the goodness and badness of the actor, and rated each actor on a relevant trait. A mediational analysis found that the behavioral predictions of older children were mediated solely by trait ratings, whereas those of younger children were mediated by evaluative ratings. Furthermore, unlike older children, younger children made trait-like predictions only when they made an evaluation of the actor. These results suggest that young children utilize evaluative reasoning when making behavioral predictions, and therefore rely on an inferential process that is distinct from that of older children.

Age Factors↗

Association between residential greenness and coronary heart disease: A proteomics and miRNA microarray analysis.

Greenness has been linked to cardiovascular disease. However, the specific biological mechanisms through which greenness impacts coronary heart disease (CHD) remain unclear. We aim to explore the underlying epigenetic mechanisms linking greenness and CHD by using proteomics and miRNA microarray. A total of 2387 participants were included in the population study, 816 of whom were diagnosed with CHD. Residential greenness exposure was characterized using the normalized difference vegetation index (NDVI). Generalized additive models and restricted cubic splines investigated the association between greenness and CHD. Mediation analysis examined whether cardiovascular metabolic risk factors (blood pressure, inflammation indicators, and glucose) mediated the association. After proteomics and miRNA microarray screening, Elisa and qRT-PCR validated selected proteins (THBS1, FCN3, and LTBP1) and miRNAs (miR-671-5p, miR-124-3p, and miR-379-5p) in CHD. Among these, LTBP1 and miR-379-5p showed significant differential expression (P&#xa0;<&#xa0;0.05) and were examined as potential molecular mediators. Higher greenness exposure within a 1000-m area was associated with a lower risk of CHD (OR: 0.86, 95&#xa0;% CI: 0.81, 0.92). Systolic blood pressure (6.32&#xa0;% [95&#xa0;% CI: 1.49&#xa0;%, 13.12&#xa0;%]), lymphocyte (10.98&#xa0;% [95&#xa0;% CI: 3.76&#xa0;%, 22.00&#xa0;%]), monocyte (9.94&#xa0;% [95&#xa0;% CI: 3.42&#xa0;%, 20.87&#xa0;%]), and fasting blood glucose (3.41&#xa0;% [95&#xa0;% CI: 0.56&#xa0;%, 7.84&#xa0;%]) mediated this association. LTBP1 and miR-379-5p were differentially expressed in CHD and mediated 7.19&#xa0;% [95&#xa0;% CI: 0.01&#xa0;%, 23.37&#xa0;%] and 20.03&#xa0;% [95&#xa0;% CI: 2.85&#xa0;%, 69.71&#xa0;%] of greenness effect on CHD, respectively. Combining the population study and experiments, we found that miR-379-5p and LTBP1 may jointly modulate vascular constriction and immune inflammation in the association between greenness and CHD.

Humans↗

Equivalence of the mediation, confounding and suppression effect.

This paper describes the statistical similarities among mediation, confounding, and suppression. Each is quantified by measuring the change in the relationship between an independent and a dependent variable after adding a third variable to the analysis. Mediation and confounding are identical statistically and can be distinguished only on conceptual grounds. Methods to determine the confidence intervals for confounding and suppression effects are proposed based on methods developed for mediated effects. Although the statistical estimation of effects and standard errors is the same, there are important conceptual differences among the three types of effects.

Bias↗

Association of the serotonin transporter gene with smoking behavior.

OBJECTIVE: In an ongoing molecular genetic study of temperament, participants were genotyped to examine the association of smoking with two polymorphisms of the serotonin transporter gene (SERT): the promoter region, 5-HTTLPR, and an intronic variable-number-of-tandem-repeats region (VNTR). METHOD: Full information was available for 330 families, and 244 "ever smokers" were identified (54 past smokers, 190 current smokers). The average number of cigarettes smoked per day was 13.12, and the mean Fagerstrom Tolerance Questionnaire score was 4.79. Associations of genotype, Tridimensional Personality Questionnaire scores, and smoking phenotype were tested by using a robust family design with a variance-components framework and by case-control analysis. RESULTS: There was a significant excess of the 5-HTTLPR long allele with the 12-repeat VNTR in current smokers, past smokers, and ever smokers, compared to participants who had never smoked. The results from the population design were confirmed in the family-based analysis. No association was observed between two quantitative measures of smoking and the polymorphisms. A weak association was observed between novelty seeking and the VNTR polymorphism and between reward and 5-HTTLPR. Smokers, regardless of gender, scored significantly higher on novelty seeking and did not differ on harm avoidance or reward. CONCLUSIONS: There was a highly significant association between SERT and the categorical definition of smoking, irrespective of dependence level, suggesting that this gene influences the initiation of smoking. Mediation analysis failed to substantiate the hypothesis that novelty seeking partially mediates the effect of SERT on smoking. SERT appears to independently contribute to novelty seeking and smoking.

Adolescent↗