Biomedical subjects

Axel Schnabel

Publications and source records attributed to Axel Schnabel.

7 recordsLinked to original sources

PubMed2007

HTR2C and HTR1A gene variants in German and Italian suicide attempters and completers.

The serotonin 2C (HTR2C) and 1A (HTR1A) receptors have been involved in suicide-related behaviors. We studied gene variants of both receptors in suicide attempters and completers. The sample was composed of 167 German suicide attempters (affective spectrum n = 107, schizophrenia spectrum n = 35, borderline personality disorder n = 25), 92 Caucasian individuals who committed suicide, 312 German healthy subjects, 152 Italian suicide attempters (major depression n = 68 and bipolar disorder n = 84), and 131 Italian healthy volunteers. HTR2C (SNP: rs547536, rs2192372, rs6318, rs2428707, rs4272555, rs1801412) and HTR1A (SNP: rs1423691, rs878567, and rs6295) variants were analyzed in the German sample. HTR2C rs6318 and HTR1A rs6295 were analyzed in the Italian sample. Haplotype analysis in relation to suicidal behaviors did not reveal any significant association. Single markers and haplotypes were not or only marginally associated with other related features, such as violence of suicide attempt, family history for suicide attempt or State-Trait Anger Expression Inventory (STAXI) and Questionnaire for Measuring Factors of Aggression (FAF) scores. In conclusion, our study does not support the notion that HTR2C and HTR1A gene variants are major contributors to suicide-, anger-, or aggression-related behaviors in our sample.

Adolescent↗

PubMed2006

ABCG1 gene variants in suicidal behavior and aggression-related traits.

The ABCG1 transporter seems to be involved in human cholesterol and sterol homeostasis. As alterations in cholesterol homeostasis have been widely linked to aggression, violence and suicidal behavior, we considered ABCG1 as a candidate gene for these traits. We studied 5 gene variants of ABCG1 in a sample of 571 suicide attempters, healthy controls and suicide completers. We also analyzed the relation to aggression-related traits, assessed by STAXI and FAF. Regarding the genotypes, there was no association with completed or attempted suicide with the tested SNPs. Regarding alleles, only one SNP (rs1044317) showed a slight association with suicide attempters in comparison to the controls. Interestingly, rs225374 G allele carriers had higher scores on the STAXI subscales "State Anger" and "Anger Out", as well as on the FAF subscales "Spontaneous Aggression", "Irritability" and "Aggression". Carriers of the rs914189 G allele scored higher on the FAF subscales "Spontaneous Aggression", "Reactive Aggression" and "Aggression". Carriers of the rs1044317 G allele had lower scores for STAXI "Trait Anger" and "Trait Temperament", and higher scores for STAXI "Anger Control". Our results provide evidence that the ABCG1 may influence aggression-related traits. Given that these represent intermediate phenotypes of suicidal behavior, ABCG1 might also act on suicidal behavior through these traits. The observed associations warrant further replications.

ATP Binding Cassette Transporter, Subfamily G, Mem↗

PubMed2006

[Risk factors for suicide in substance-related disorders].

OBJECTIVE: To assess the contribution of sociodemographic and psychopathologic predictors for suicide in alcohol-related disorders and in substance-related disorders in general and to examine the constellations of risk factors for suicide. METHODS: Out of 163 suicides (using psychological autopsy method) and 396 population-based control persons, 67 suicides and 67 controls with substance-related disorders (DSM-IV; alcohol-related disorders: suicides: n = 36, controls: n = 27) were assessed. RESULTS: Affective disorders, suffering from substance dependence, and low education independently predicted increased suicide risk in alcohol-related disorders as well as in substance-related disorders in general, severe nicotine consumption only in alcohol-related disorders. CONCLUSIONS: There are common risk factors for suicide in alcoholism and substance-related disorders in general. Effective suicide prevention strategies must include a focus on substance dependence as well as on affective disorders.

Adult↗

PubMed2005

Axis I disorders and personality disorders as risk factors for suicide.

There is a lack of psychological autopsy studies assessing the influence of axis I disorders on axis II disorders as risk factors for suicide. Therefore, we investigated the association between personality disorders, axis I disorders, and suicide. Psychiatric disorders were evaluated by a semi-structured interview including the Structured Clinical Interview for DSM-IV Axis I (SCID-I) and Personality Disorders (SCID-II) in 163 completed suicides (mean age 49.6 +/- 19.3 years; 64.4% men) and by personal interview in 396 population-based control persons (mean age 51.6 +/- 17.0 years; 55.8% men). In both genders, suicides significantly more often had personality disorders of all clusters than controls, also after adjustment for axis I disorders (p < 0.001, each). In addition, alcohol-related disorders, major depression, and co-occurrence of personality disorders of more than one cluster (men: OR = 16.13; women: OR = 20.43) remained independent predictors for suicide in both genders, "pure" cluster B personality disorders only in women and "pure" cluster C personality disorders only in men. In both genders, co-occurrence of personality disorders of more than one cluster contributed to risk of completed suicide after control for axis I psychiatric disorders and has to be considered as an independent risk factor for suicide.

Adult↗

PubMed2005

Nicotine use in suicides: a case-control study.

PURPOSE: Despite of higher rates of substance-related disorders in psychiatric patients and suicides than in the general population, there is no clear specificity to the relationship between nicotine use and other psychiatric disorders for suicide risk. METHODS: One hundred and sixty-three suicides (mean age 49.8 +/- 19.3 years; 64.4% males; using psychological autopsy method) and 396 control persons (mean age 51.6 +/- 17.0 years; 55.8% males) were assessed with a standardised semi-structured interview including SCID-I and SCID-II (for DSM-IV). Suicides and controls were compared in terms of nicotine consumption and psychiatric disorders. Logistic regression was used to evaluate the interactions of tobacco consumption with psychiatric disorders. RESULTS: Suicides were significantly more often current smokers and heavy users of cigarettes (> 20 cigarettes per day; P < 0.001, each). Alcohol dependence, other axis I disorders than substance-related disorders, and cluster B personality disorder(s) remained independent predictors for suicide in both genders, current nicotine consumption only in men (OR = 2.6, 95% CI 1.3-5.2). DISCUSSION AND CONCLUSIONS: In males, but not in females, nicotine consumption contributed to risk of completed suicide after control for psychiatric disorders and has to be considered as independent risk factor for suicide.

Autopsy↗

PubMed2005

[Age and gender: confounders for axis I disorders as risk factors for suicide].

OBJECTIVES AND METHODS: Aim of the study was to identify and estimate psychiatric axis I disorders as risk factors for suicide in different age groups using a psychological autopsy study with case-control design. 163 suicides and 396 population-based control persons were assessed with a standardized semi-structured interview including SCID-I (for DSM-IV). RESULTS: Logistic regression analyses revealed significantly elevated odds ratios for alcohol-related disorders in men aged 31 to 45, 46 to 60, and 61 to 75 years (OR = 9.0, OR = 7.5, and OR = 10.7, respectively) and for Major Depression, single episode, in men and women aged 61 to 75 years (OR = 42.7 and OR = 15.9). In males aged 31 to 45 years polysubstance-related disorders (OR = 9.5) and in females aged 61 to 75 years cognitive and mental disorders due to a general medical condition (OR = 12.2) were significantly and independently associated with suicide. CONCLUSIONS: Alcohol-related disorders and Major Depression differently contribute to male and female suicide risk in special age groups. These findings imply differentiated prevention strategies.

Adult↗

PubMed2004

Detection of alcohol consumption in suicides.

Screening instruments for detection of alcohol consumption, abuse, and dependence for use in psychological autopsy studies with case control design are not validated. Therefore, interrater and test-retest reliability of the Luebeck Alcohol Dependence and Abuse Screening Test (LAST) and the usability of this test for the psychological autopsy method were investigated. Alcohol consumption was evaluated by a semi-structured interview including the Structured Clinical Interview for DSM-IV Axis I (SCID-I) and the LAST in 163 completed suicides (mean age 49.6 +/- 19.3 years; 64.4% men) and by personal interview in 396 population-based controls (mean age 51.6 +/- 17.0 years; 55.8% men). Of the controls, 35 were additionally assessed by interviewing informants; these results were compared with those generated by personal interview. Comparison of LAST scores by personal and informant's interview of controls generated a Spearman correlation coefficient of 0.74 (P < 0.0001). The LAST (7 item-version, cut-off of 2) revealed high sensitivity and specificity for alcohol abuse and dependence, in both controls and suicides. LAST scores were significantly associated with high, frequent, and hazardous alcohol consumption (P < 0.001) in suicides. Our findings provide support for reliability and validity of identifying individuals with alcohol dependence and abuse obtained through the best-estimate method using the LAST. This 7-item questionnaire can be recommended as a useful tool for the psychological autopsy procedure in postmortem research.

Adult↗