Aksel Bertelsen

A Comprehensive Nationwide Study of the Incidence Rate and Lifetime Risk for Treated Mental Disorders

IMPORTANCE Understanding the epidemiologic profile of the life course of mental disorders is fundamental for research and planning for health care. Although previous studies have used population surveys, informative and complementary estimates can be derived from population-based registers. OBJECTIVE To derive comprehensive and precise estimates of the incidence rate of and lifetime risk for any mental disorder and a range of specific mental disorders. DESIGN, SETTING, AND PARTICIPANTS We conducted a follow-up study of all Danish residents (5.6 million persons), to whom all treatment is provided by the government health care system without charge to the patient, from January 1, 2000, through December 31, 2012 (total follow-up, 59.5 million person-years). During the study period, 320,543 persons received first lifetime treatment in a psychiatric setting for any mental disorder; 489,006 persons were censored owing to death; and 69,987 persons were censored owing to emigration. Specific categories of mental disorders investigated included organic mental disorders, substance abuse disorders, schizophrenia, mood disorders, anxiety, eating disorders, personality disorders, mental retardation, pervasive developmental disorders, and behavioral and emotional disorders. EXPOSURES Age and sex. MAIN OUTCOMES AND MEASURES Sex- and age-specific incidence rates and cumulative incidences and sex-specific lifetime risks. RESULTS During the course of life, 37.66% of females (95% CI, 37.52%-37.80%) and 32.05% of males (31.91%-32.19%) received their first treatment in a psychiatric setting for any mental disorder. The occurrence of mental disorders varied markedly between diagnostic categories and by sex and age. The sex- and age-specific incidence rates for many mental disorders had a single peak incidence rate during the second and third decades of life. Some disorders had a second peak in the sex- and age-specific incidence rate later in life. CONCLUSIONS AND RELEVANCE This nationwide study provides a first comprehensive assessment of the lifetime risks for treated mental disorders. Approximately one-third of the Danish population received treatment for mental disorders. The distinct signatures of the different mental disorders with respect to sex and age have important implications for service planning and etiologic research.

Severe Mental Disorders in Offspring With 2 Psychiatrically Ill Parents

BACKGROUND Studies of couples of psychiatric patients with children allow us to calculate the effects of double predispositions on morbid risk in the offspring, which is of interest for molecular genetic research and for genetic counseling. OBJECTIVE To determine the risks in offspring of receiving a diagnosis of schizophrenia, bipolar disorder, unipolar depressive disorder, or any diagnosis from parents who both have received a diagnosis of schizophrenia or bipolar disorder. DESIGN National register-based cohort study. SETTING Denmark. PARTICIPANTS A population-based cohort of 2.7 million persons born in Denmark, alive in 1968 or born later than 1968, with a register link to their mother and father and aged 10 years or older in 2007. MAIN OUTCOME MEASURE Risk of schizophrenia or bipolar disorder, calculated as cumulative incidences by age 52 years. RESULTS The risk of schizophrenia in 270 offspring of 196 parent couples who were both admitted to a psychiatric facility with a diagnosis of schizophrenia was 27.3% (increasing to 39.2% when schizophrenia-related disorders were included) compared with 7.0% in 13 878 offspring from 8006 couples with only 1 parent ever admitted for schizophrenia and 0.86% in 2 239 551 offspring of 1 080 030 couples with neither parent ever admitted. The risk of bipolar disorder was 24.9% in 146 offspring of 83 parent couples who were ever admitted with bipolar disorder (increasing to 36.0% when unipolar depressive disorder was included) compared with 4.4% in 23 152 offspring from 11 995 couples with only 1 parent ever admitted and 0.48% in 2 239 553 offspring of 1 080 030 couples with neither parent ever admitted. Risks of schizophrenia and bipolar disorder in offspring of couples with 1 parent with schizophrenia and the other with bipolar disorder were 15.6% and 11.7%, respectively. The maximal risks of any psychiatric disorders in the offspring of parents both with schizophrenia or both with bipolar disorder were 67.5% and 44.2%, respectively. CONCLUSIONS Derived risks may be informative for counseling. Patterns of transmission may support evolving assumptions about genetic overlap for traditional categories.

Psychoactive substance use diagnoses among psychiatric in‐patients

Objective: To estimate the prevalence and possible under‐diagnosing of substance use disorders and to consider factors that might influence diagnosing of substance use disorders.

Incidence and diagnostic stability of ICD-10 acute and transient psychotic disorders

OBJECTIVE The 10th Revision of the International Classification of Diseases (ICD-10) introduced a new diagnostic category, F23 acute and transient psychotic disorders (ATPD) to embrace clinical concepts such as the French bouffée délirante, Kleist and Leonhards cycloid psychoses, and the Scandinavian reactive and schizophreniform psychoses. The relative rarity of these disorders and insufficient follow-up studies with adequate numbers of patients makes ATPD classification as uncertain as their validity. The aim of this study was to evaluate incidence and validity of ATPD in terms of diagnostic stability. METHOD A 6-year analysis of readmission patterns of all subjects listed in the Danish psychiatric central register as having been first-ever admitted to hospital or treated in outpatient services with a diagnosis of ATPD from January 1 to December 31, 1996, was conducted. RESULTS The incidence of ATPD was 9.6 per 100 000 population, with a higher rate of females than males (9.8 vs 9.4). Incidence rates by age group were higher for males than for females, with a marked reversal of this pattern above 50 years. This contrasted with incidence of schizophrenia that was almost twice as high in males as in females, particularly in the 20-29 year age group. Of 416 cases with a first-admission diagnosis of ATPD, an increasing number tended to change on subsequent admissions, nearly half to another F2 category schizophrenia and related disorders. The overall stability rate reached only 39%. CONCLUSIONS Although demographic differences from schizophrenia are topics that deserve further research, poor diagnostic stability argues against attempts to separate ATPD from borderland disorders.

Use of the ICD-10 Classification in Psychiatry: An International Survey

On the background of some years of experience with ICD-10 psychiatric diagnoses in many countries of the world, an international comparison was performed to evaluate the frequency and use of the ICD-10 psychiatric diagnoses. For future revision of the ICD-10, it is important to know which diagnostic categories are either not used or are used possibly in an unspecific manner. Nineteen departments of psychiatry in 10 different countries took part in the study, presenting data on 33,857 treatment cases leading to a total of 25,470 ICD-10 main diagnoses. The analysis of data reveals that on a four-character level (Fxx.x), the 10 most often used diagnostic categories represent 40% of all main diagnoses, and 70% on a three-character level (Fxx.–). There are 32 specific diagnostic categories on a four-character level which are not used at all and 121 which are used less frequently than 0.1% in inpatient and outpatient treatment. The study shows that the ICD-10 classification is in use in a variety of treatment settings worldwide. Further results and limitations of this study are discussed against the background of transcultural differences.

Schizophrenia and related disorders: experience with current diagnostic systems.

Schizophrenia and related disorders include a variety of psychotic disorders in the major classification systems, ICD-10 and DSM-IV, with only partial concordance between the two systems. They both rely on demonstrated reliability, but which disorders are the most valid still has to be determined. Particularly for the ICD-10 disorders, only few studies examining external validity have appeared. Disorders of uncertain validity include ‘schizo-affective disorders’ which in ICD-10 contain the DSM-IV psychotic mood disorders with first-rank symptoms or bizarre delusions; ICD-10 ‘schizotypal disorder’ which in DSM-IV is a personality disorder; the ICD-10 ‘acute and transient psychotic disorders’ and the DSM-IV ‘brief psychotic disorder’. Concerning diagnostic criteria, the reliability and validity of Schneiderian first-rank symptoms, ‘bizarre’ delusions and the Bleulerian ‘negative’ symptoms have been questioned. Validity studies in these areas are needed before it will be possible to provide major reconstructions for future diagnostic systems. One may hope that, eventually, one common worldwide psychiatric classification will be available.

The association between psychotic mania, psychotic depression and mixed affective episodes among 14,529 patients with bipolar disorder

BACKGROUND Psychotic and mixed affective episodes are prevalent in the course of bipolar disorder. Despite many studies on the implications of psychotic mania (PM), psychotic depression (PD) and mixed affective episodes (MAE), relatively little is known about the relationship between the three subtypes. The present study aimed to investigate whether the occurrence of PM, PD and MAE were associated with one another. METHODS This is a nationwide register-based, historical prospective cohort study. Data was obtained from the Danish Psychiatric Central Research Register. Subjects were defined as all individuals assigned with an ICD-10 diagnosis of bipolar disorder between January 1st 1994 and December 31st 2010. Potential associations among psychotic and mixed affective episodes were tested by means of logistic regression. RESULTS We identified 14,529 individuals with bipolar disorder with lifetime incidences of PM, PD and MAE of 19%, 15% and 17% respectively. We detected significant associations between PM and MAE (Adjusted Odds Ratio (AOR)=1.26, p=0.003), PD and MAE (AOR=1.24, p=0.001), and PM and PD (AOR=1.28, p=0.005). LIMITATIONS Diagnoses were assigned as part of routine clinical practice. CONCLUSIONS According to this register-based study, PD, PM and MAE are all associated with one another. This knowledge should be taken into consideration by clinicians when monitoring patients with bipolar disorder and by nosologists when defining the criteria and potential subtypes for mixed affective episodes for the upcoming DSM-5 and ICD-11.

Excess mortality of acute and transient psychotic disorders: comparison with bipolar affective disorder and schizophrenia

To investigate mortality and causes of death of short‐lived psychotic disorders, by carrying out a comparison with bipolar disorder and schizophrenia.

Long-term stability of acute and transient psychotic disorders.

Objective: To examine the temporal stability of the category ‘acute and transient psychotic disorders’ (ATPDs), ICD-10 Classification of Mental and Behavioural Disorders, including subtypes characterised by polymorphic, schizophrenic and predominantly delusional features. Method: We checked the readmission patterns of all patients aged 15–64 years (n = 5426), whether admitted to hospital or treated as outpatients, who were enrolled for the first time in the Danish Psychiatric Register with a diagnosis of ATPDs between 1995 and 2008. Results: An increasing number of cases with ATPDs changed diagnosis in subsequent admissions after 1, 2 and 5 years, mainly either to schizophrenia and related disorders or affective disorders. In their last admission, on average after 7.3 years, there were 2429 patients listed with ATPDs, accounting for an overall stability of 44.8%. Females were less likely than males to develop another diagnosis. Among the ATPD subtypes, polymorphic psychotic disorder without schizophrenic symptoms had a higher stability than those featuring schizophrenic or predominantly delusional features. Conclusions: The low diagnostic stability of ATPDs reflects the lack of clearly defining features and argues against their validity as a distinct category.

Reflections on the clinical utility of the ICD-10 and DSM-IV classifications and their diagnostic criteria

Objective: The change to non-theoretical, criteria-based diagnostic classification in ICD-10 and DSM-III/IV has presented a major innovation in clinical psychiatry. The aim of the present paper is to provide a provisional evaluation of their utility in clinical practice. Method: The method involved a close scrutiny of ICD-10 and DSM-IV with a view to identifying difficulties and problems in their use. Results and Conclusions: The criteria-based classifications are no longer just coding conventions, but have become part of the conceptual framework of the discipline itself. The advantages, particularly as to the quality and reliability of clinical diagnoses, outweigh the disadvantages with temptations to mechanistic and reductionistic applications of criteria and incomplete nosological evaluation. Comprehensive clinical evaluation, however, should work at two separate levels: one, the initial, syndromatical diagnostic level, followed by the other, the nosological level, with evaluation of factors possibly influencing course and outcome of the psychiatric disorders. Only when both the syndromatical diagnosis and nosological factors are taken into consideration, is it possible to get a full understanding of the disorder necessary for optimal treatment. In this way, clinical psychiatry can be kept as it was intended: a healing discipline.