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Hans-Ulrich Wittchen

Publications and source records attributed to Hans-Ulrich Wittchen.

At least 37 records · Page 2Linked to original sources
PubMed2005

Dependence symptoms in young cannabis users? A prospective epidemiological study.

AIM: To examine prospectively over a period of 4 years the profile of cannabis dependence and the risk of specific dependence criteria in a community sample of adolescents. METHODS: A representative community sample of 2446 young adults aged 14-24 years at baseline was followed up over a period of 4 years. Frequency of use measures and of criteria for DSM-IV dependence were assessed by standardized diagnostic interview measures (CIDI). To explore the nature of this association, frequency of use and concomitant use of other psychoactive substances was considered. RESULTS: 30% of the sample were cannabis users. Among all users 35% met at least one dependence criterion. Most frequently reported dependence criteria among all users were withdrawal (17%), tolerance (15%), loss of control (14%) and continued use despite a health problem (13%). Even without concomitant use of other illicit drugs, 22% of low frequency users and 81% of high frequency users met at least one dependence criterion. Symptom patterns were similar in high and low frequency users. The occurrence of a dependence syndrome or of specific dependence criteria could not be attributed to the use of other illicit drugs or to comorbid nicotine and alcohol dependence. CONCLUSIONS: Regular cannabis use in adolescence is associated with the development of a dependence syndrome. This association cannot be explained by the concomitant use of other illicit substances or by comorbid nicotine and alcohol dependence.

Adolescent↗
PubMed2005

Calculating control variables with age at onset data to adjust for conditions prior to exposure.

BACKGROUND: When assessing the association between a factor X and a subsequent outcome Y in observational studies, the question that arises is what are the variables to adjust for to reduce bias due to confounding for causal inference on the effect of X on Y. Disregarding such factors is often a source of overestimation because these variables may affect both X and Y. On the other hand, adjustment for such variables can also be a source of underestimation because such variables may be the causal consequence of X and part of the mechanism that leads from X to Y. METHODS: In this paper, we present a simple method to compute control variables in the presence of age at onset data on both X and a set of other variables. Using these age at onset data, control variables are computed that adjust only for conditions that occur prior to X. This strategy can be used in prospective as well as in survival analysis. Our method is motivated by an argument based on the counterfactual model of a causal effect. RESULTS: The procedure is exemplified by examining of the relation between panic attack and the subsequent incidence of MDD. CONCLUSIONS: The results reveal that the adjustment for all other variables, irrespective of their temporal relation to X, can yield a false negative result (despite unconsidered confounders and other sources of bias).

Adolescent↗
PubMed2005

Pathways into ecstasy use: the role of prior cannabis use and ecstasy availability.

AIM: To explore the role of cannabis use for the availability of ecstasy as a potential pathway to subsequent first ecstasy use. METHODS: Baseline and 4-year follow-up data from a prospective-longitudinal community study of originally 3021 adolescents and young adults aged 14-24 years at baseline were assessed using the standardized M-CIDI and DSM-IV criteria. RESULTS: Baseline cannabis users reported at follow-up more frequent access to ecstasy than cannabis non-users. Higher cannabis use frequencies were associated with increased ecstasy availability reports. Logistic regression analyses revealed that cannabis use and availability of ecstasy at baseline are predictors for incident ecstasy use during the follow-up period. Testing simultaneously the impact of prior cannabis use and ecstasy availability including potential confounders, the association with cannabis use and later ecstasy use was confirmed (OR=6.3; 95%CI=3.6-10.9). However, the association with ecstasy availability was no longer significant (OR=1.2; 95%CI=0.3-3.9). CONCLUSIONS: Results suggest that cannabis use is a powerful risk factor for subsequent first onset of ecstasy use and this relation cannot be sufficiently explained by availability of ecstasy in the observation period.

Adolescent↗
PubMed2005

Buprenorphine and methadone in the treatment of opioid dependence: methods and design of the COBRA study.

Buprenorphine and methadone are the two established substitution drugs licensed in many countries for the treatment of opioid dependence. Little is known, however, about how these two drugs are applied and how they work in clinical practice. In this paper we present the aims, methods, design and sampling issues of a collaborative multi-stage epidemiological study (COBRA) to address these issues. Based on a nationally representative sample of substitution physicians, the study is designed as an observational, naturalistic study, consisting of three major parts. The first part was a national survey of substitution doctors (prestudy, n = 379 doctors). The second part was a cross-sectional study (n = 223 doctors), which consisted of a target-week assessment of 2,694 consecutive patients to determine (a) the severity and problem profiles and treatment targets; (b) the choice and dosage scheme of the substitution drug; (c) past and current interventions, including treatment of comorbid hepatitis C; and (d) cross-sectional differences between the two drugs with regard to comorbidity, clinical course, acceptance/compliance and social integration. The third part consists of a prospective-longitudinal cohort study of 48 methadone-treated and 48 buprenorphine-treated patients. The cohort is followed up over a period of 12 months to investigate whether course and outcome of the patients differ by type or treatment received in terms of clinical, psychosocial, pharmaco-economic and other related measures. The response rate among substitution doctors was 57.1%; that among eligible patients was 71.7%. Comparisons with the federal registers reveal that the final samples of doctors and patients may be considered nationally representative with regard to regional distribution, training, type of setting as well as the frequency of patients treated with buprenorphine or methadone. The COBRA study provides a unique comprehensive database, informing about the natural allocation and intervention processes in routine care and about the course and outcome of patients treated with buprenorphine or methadone.

Buprenorphine↗
PubMed2005

The use of weights to account for non-response and drop-out.

BACKGROUND: Empirical studies in psychiatric research and other fields often show substantially high refusal and drop-out rates. Non-participation and drop-out may introduce a bias whose magnitude depends on how strongly its determinants are related to the respective parameter of interest. METHODS: When most information is missing, the standard approach is to estimate each respondent's probability of participating and assign each respondent a weight that is inversely proportional to this probability. This paper contains a review of the major ideas and principles regarding the computation of statistical weights and the analysis of weighted data. RESULTS: A short software review for weighted data is provided and the use of statistical weights is illustrated through data from the EDSP (Early Developmental Stages of Psychopathology) Study. The results show that disregarding different sampling and response probabilities can have a major impact on estimated odds ratios. CONCLUSIONS: The benefit of using statistical weights in reducing sampling bias should be balanced against increased variances in the weighted parameter estimates.

Adolescent↗
PubMed2005

Size and burden of social phobia in Europe.

This paper provides a critical review of the prevalence of social phobia in European countries, a description of associated disability and burden and of clinical correlates and risk factors associated with social phobia. On the basis of a comprehensive literature search we identified 21 community studies and two primary care studies. The median lifetime and 12-month prevalence rates of social phobia in community samples referring to DSM-III-R and DSM-IV criteria were 6.65% and 2.0%, respectively. Younger individuals showed the highest rates, and women were more frequently affected than men. Social phobia was shown to be a persistent condition with a remarkably high degree of comorbid conditions, associated impairment and disability. Research deficits lie in a lack of data for most EU countries and in a lack of studies in children and the elderly. No data are available addressing met and unmet needs for intervention and costs, and data for vulnerability and risk factors of malignant course are scarce.

Age of Onset↗
PubMed2005

Prevalence and burden of bipolar disorders in European countries.

A literature search, supplemented by an expert survey and selected reanalyses of existing data from epidemiological studies was performed to determine the prevalence and associated burden of bipolar I and II disorder in EU countries. Only studies using established diagnostic instruments based on DSM-III-R or DSM-IV, or ICD-10 criteria were considered. Fourteen studies from a total of 10 countries were identified. The majority of studies reported 12-month estimates of approximately 1% (range 0.5-1.1%), with little evidence of a gender difference. The cumulative lifetime incidence (two prospective-longitudinal studies) is slightly higher (1.5-2%); and when the wider range of bipolar spectrum disorders is considered estimates increased to approximately 6%. Few studies have reported separate estimates for bipolar I and II disorders. Age of first onset of bipolar disorder is most frequently reported in late adolescence and early adulthood. A high degree of concurrent and sequential comorbidity with other mental disorders and physical illnesses is common. Most studies suggest equally high or even higher levels of impairments and disabilities of bipolar disorders as compared to major depression and schizophrenia. Few data are available on treatment and health care utilization.

Age Factors↗
PubMed2005

Size and burden of mental disorders in Europe--a critical review and appraisal of 27 studies.

Epidemiological data on a wide range of mental disorders from community studies conducted in European countries are presented to determine the availability and consistency of prevalence, disability and treatment findings for the EU. Using a stepwise multimethod approach, 27 eligible studies with quite variable designs and methods including over 150,000 subjects from 16 European countries were identified. Prevalence: On the basis of meta-analytic techniques as well as on reanalyses of selected data sets, it is estimated that about 27% (equals 82.7 million; 95% CI: 78.5-87.1) of the adult EU population, 18-65 of age, is or has been affected by at least one mental disorder in the past 12 months. Taking into account the considerable degree of comorbidity (about one third had more than one disorder), the most frequent disorders are anxiety disorders, depressive, somatoform and substance dependence disorders. When taking into account design, sampling and other methodological differences between studies, little evidence seems to exist for considerable cultural or country variation. Disability and treatment: despite very divergent and fairly crude assessment strategies, the available data consistently demonstrate (a) an association of all mental disorders with a considerable disability burden in terms of number of work days lost (WLD) and (b) generally low utilization and treatment rates. Only 26% of all cases had any consultation with professional health care services, a finding suggesting a considerable degree of unmet need. The paper highlights considerable future research needs for coordinated EU studies across all disorders and age groups. As prevalence estimates could not simply be equated with defined treatment needs, such studies should determine the degree of met and unmet needs for services by taking into account severity, disability and comorbidity. These needs are most pronounced for the new EU member states as well as more generally for adolescent and older populations.

Absenteeism↗
PubMed2005

Rethinking the duration requirement for generalized anxiety disorder: evidence from the National Comorbidity Survey Replication.

BACKGROUND: The proposed revisions of the ICD and DSM diagnostic systems have led to increased interest in evaluation of diagnostic criteria. This report focuses on the DSM-IV requirement that episodes of generalized anxiety disorder (GAD) must persist for at least 6 months. Community epidemiological data are used to study the implications of changing this requirement in the range 1-12 months for estimates of prevalence, onset, course, impairment, co-morbidity, associations with parental GAD, and sociodemographic correlates. METHOD: Data come from the US National Comorbidity Survey Replication (NCS-R), a US household survey carried out during 2001-2003. Version 3.0 of the WHO Composite International Diagnostic Interview (WMH-CIDI) was used to assess DSM-IV anxiety disorders, mood disorders, substance disorders, and impulse-control disorders. RESULTS: Lifetime, 12-month, and 30-day prevalence estimates of DSM-IV GAD changed from 6.1%, 2.9%, and 1.8% to 4.2-12.7%, 2.2-5.5%, and 1.6-2.6% when the duration requirement was changed from 6 months to 1-12 months. Cases with episodes of 1-5 months did not differ greatly from those with episodes of > or = 6 months in onset, persistence, impairment, co-morbidity, parental GAD, or sociodemographic correlates. CONCLUSIONS: A large number of people suffer from a GAD-like syndrome with episodes of < 6 months duration. Little basis for excluding these people from a diagnosis is found in the associations examined here.

Adult↗
PubMed2005

Should excessive worry be required for a diagnosis of generalized anxiety disorder? Results from the US National Comorbidity Survey Replication.

BACKGROUND: Excessive worry is required by DSM-IV, but not ICD-10, for a diagnosis of generalized anxiety disorder (GAD). No large-scale epidemiological study has ever examined the implications of this requirement for estimates of prevalence, severity, or correlates of GAD. METHOD: Data were analyzed from the US National Comorbidity Survey Replication, a nationally representative, face-to-face survey of adults in the USA household population that was fielded in 2001-2003. DSM-IV GAD was assessed with Version 3.0 of the WHO Composite International Diagnostic Interview. Non-excessive worriers meeting all other DSM-IV criteria for GAD were compared with respondents who met full GAD criteria as well as with other survey respondents to consider the implications of removing the excessiveness requirement. RESULTS: The estimated lifetime prevalence of GAD increases by approximately 40% when the excessiveness requirement is removed. Excessive GAD begins earlier in life, has a more chronic course, and is associated with greater symptom severity and psychiatric co-morbidity than non-excessive GAD. However, non-excessive cases nonetheless evidence substantial persistence and impairment of GAD, high rates of treatment-seeking, and significantly elevated co-morbidity compared with respondents without GAD. Non-excessive cases also have sociodemographic characteristics and familial aggregation of GAD comparable to excessive cases. CONCLUSIONS: Individuals who meet all criteria for GAD other than excessiveness have a somewhat milder presentation than those with excessive worry, yet resemble excessive worriers in a number of important ways. These findings challenge the validity of the excessiveness requirement and highlight the need for further research into the optimal definition of GAD.

Adolescent↗
PubMed2005

Mania, hypomania, and suicidality: findings from a prospective community study.

We examined prospectively whether mania and hypomania are associated with an elevated risk for suicidality in a community sample of adolescents and young adults. Baseline and four-year follow-up data were used from the Early-Developmental-Stages-of-Psychopathology (EDSP) Study, a prospective longitudinal study of adolescents and young adults in Munich. Suicidal tendencies (ideation/attempts), mania, and hypomania were assessed using the standardized Munich-Composite-International-Diagnostic-Interview. At baseline, mania/hypomania was associated to a different degree with suicidality (Odds ratios [OR] range from 1.9 to 13.7). In the prospective analyses, the risk for subsequent incident suicidal ideation was increased in the presence of prior mania (38.0% vs. 14.1%; OR = 4.4; 95% CI = 1.4-13.5). No associations could be found between prior mania/hypo-mania and incident suicide attempts. The prospective analyses revealed a remarkable relationship between preexisting mania and increased risk for subsequent suicidal ideation.

Adolescent↗
PubMed2005

Longitudinal course of posttraumatic stress disorder and posttraumatic stress disorder symptoms in a community sample of adolescents and young adults.

OBJECTIVE: Few studies have focused on the natural course of posttraumatic stress disorder (PTSD) and its determinants in samples of the general population. The authors examined determinants of remission and chronicity of PTSD and associations with other disorders in a prospective community sample. METHOD: The data were drawn from a prospective, longitudinal epidemiological study of adolescents and young adults (age 14-24 years) in Munich, Germany (N=2,548). The course of PTSD from baseline to follow-up 34-50 months later was studied in 125 respondents with DSM-IV PTSD or subthreshold PTSD at baseline. RESULTS: Although 52% of the PTSD cases remitted during the follow-up period, 48% showed no significant remission of PTSD symptoms. Respondents with a chronic course were more likely to experience new traumatic event(s) during follow-up (odds ratio=5.21, 95% confidence interval [CI]=1.95-13.92), to have higher rates of avoidant symptoms at baseline (odds ratio=10.16, 95% CI=1.73-59.51), and to report more help seeking (odds ratio=5.50, 95% CI=1.04-29.05), compared to respondents with remission. Rates of incident somatoform disorder (odds ratio=4.24, 95% CI=1.60-11.19) and other anxiety disorders (odds ratio=4.07, 95% CI=1.15-14.37) were also significantly associated with a chronic course. CONCLUSIONS: PTSD is often a persistent and chronic disorder. Specific symptom clusters--especially avoidant symptoms--might be associated with the course of PTSD. In addition, the occurrence of new traumatic events differentiates PTSD cases with a chronic course from those with remission.

Adolescent↗
PubMed2005

Maternal suicidality and risk of suicidality in offspring: findings from a community study.

OBJECTIVE: This study evaluated the associations between suicidal ideation and suicide attempts in mothers and various aspects of suicidality in their offspring in a representative community sample. METHOD: Baseline and 4-year follow-up data were used from the Early Developmental Stages of Psychopathology study, a prospective, longitudinal community study of adolescents and young adults. Results are based on 933 adolescents who completed follow-up and for whom direct diagnostic information for the biological mother was available. Suicidal ideation and suicide attempts were assessed in adolescents and mothers with the Munich-Composite International Diagnostic Interview. RESULTS: Compared to offspring of mothers without suicidality, offspring of mothers reporting suicide attempts showed a remarkably higher risk for suicidal thoughts and suicide attempts and a tendency toward suicide attempts at an earlier age. Associations were comparable for male and female offspring. Transmission of maternal suicidality was roughly stable with control for maternal comorbid psychopathology. CONCLUSIONS: The offspring of mothers with suicide attempts are at a markedly increased risk for suicidality themselves and tend to manifest suicide attempts earlier than offspring of mothers without suicidality. Suicidality seems to run in families, independent of depression and other psychopathology.

Adolescent↗
PubMed2004

Prospective cohort study of cannabis use, predisposition for psychosis, and psychotic symptoms in young people.

OBJECTIVE: To investigate the relation between cannabis use and psychotic symptoms in individuals with above average predisposition for psychosis who first used cannabis during adolescence. DESIGN: Analysis of prospective data from a population based sample. Assessment of substance use, predisposition for psychosis, and psychotic symptoms was based on standardised personal interviews at baseline and at follow up four years later. PARTICIPANTS: 2437 young people (aged 14 to 24 years) with and without predisposition for psychosis. MAIN OUTCOME MEASURE: Psychotic symptoms at follow up as a function of cannabis use and predisposition for psychosis at baseline. RESULTS: After adjustment for age, sex, socioeconomic status, urbanicity, childhood trauma, predisposition for psychosis at baseline, and use of other drugs, tobacco, and alcohol, cannabis use at baseline increased the cumulative incidence of psychotic symptoms at follow up four years later (adjusted odds ratio 1.67, 95% confidence interval 1.13 to 2.46). The effect of cannabis use was much stronger in those with any predisposition for psychosis at baseline (23.8% adjusted difference in risk, 95% confidence interval 7.9 to 39.7, P = 0.003) than in those without (5.6%, 0.4 to 10.8, P = 0.033). The risk difference in the "predisposition" group was significantly greater than the risk difference in the "no predisposition" group (test for interaction 18.2%, 1.6 to 34.8, P = 0.032). There was a dose-response relation with increasing frequency of cannabis use. Predisposition for psychosis at baseline did not significantly predict cannabis use four years later (adjusted odds ratio 1.42, 95% confidence interval 0.88 to 2.31). CONCLUSION: Cannabis use moderately increases the risk of psychotic symptoms in young people but has a much stronger effect in those with evidence of predisposition for psychosis.

Adolescent↗
PubMed2004

Social Phobia in an Italian region: do Italian studies show lower frequencies than community surveys conducted in other European countries?

BACKGROUND: The lifetime prevalence of Social Phobia (SP) in European countries other than Italy has been estimated to range from 3.5% to 16.0%. The aim of this study was to assess the frequency of SP in Sardinia (Italy) in order to verify the evidence of a lower frequency of SP in Italy observed in previous studies (from 1.0% to 3.1%). METHODS: A randomised cross sample of 1040 subjects, living in Cagliari, in rural areas, and in a mining district in Sardinia were interviewed using a Simplified version of the Composite International Diagnostic Interview (CIDIS). Diagnoses were made according to the 10th International Classification of Diseases (ICD-10). RESULTS: Lifetime prevalence of SP was 2.2% (males: 1.5%, females: 2.8%) whereas 6-month prevalence resulted in 1.5% (males: 0.9%, females: 2.1%). Mean age at onset was 16.2 +/- 9.3 years. A statistically significant association was found with Depressive Episode, Dysthymia and Generalized Anxiety Disorder. CONCLUSIONS: The study is consistent with findings reported in several previous studies of a lower prevalence of SP in Italy. Furthermore, the results confirm the fact that SP, due to its early onset, might constitute an ideal target for early treatment aimed at preventing both the accumulation of social disabilities and impairments caused by anxiety and avoidance behaviour, as well as the onset of more serious, associated complications in later stages of the illness.

Cross-Cultural Comparison↗
PubMed2004

[The use of guidelines in the primary care management of hypertension and diabetes].

OBJECTIVES: The paper examines to what degree German primary care physicians know and work along the rules established in guidelines for arterial hypertension and diabetes mellitus. METHODS: HYDRA is a 2-stage cross-sectional point prevalence study with 1912 participating primary care settings throughout Germany including 45,125 patients. A pre-study questionnaire to assess doctors practice patterns was used. Subsequently doctors completed a structured clinical appraisal with a diagnostic workup and characterization of the current treatments provided. All patients filled out a questionnaire. RESULTS: Pre-study results show that only every second primary care physician manages the patients according to established guidelines. Further, physicians estimated their own work as problematic and not always successful. Guideline-oriented doctors were more likely to report hypertension and diabetes treatment patterns that also match guideline's recommendations. CONCLUSIONS: The study shows a considerable degree of dissatisfaction with the quality of their work among primary care physicians. Guideline-oriented doctors however reveal more frequently formally adequate management characteristics. This encouraging aspect suggests the need of more successful implementation of medical guidelines in order to achieve improved evidence-based medicine and better patient-oriented health care.

Adult↗