Reproductive patterns in psychotic patients☆,☆☆
Introduction
Longitudinal epidemiological studies have shown worse outcomes in patients with schizophrenia and bipolar disorder (psychotic disorders) than in patients with other psychiatric disorders and in the general population. These outcomes include markedly elevated mortality rates from all causes of death (Harris & Barraclough, 1998, Laursen et al., 2007b), suicide (Hiroeh et al., 2001), increased somatic and medical comorbidity (Laursen et al., 2009, Jeste et al., 1996), more unhealthy diets (Brown et al., 1999), higher rates of cigarette smoking (Itkin et al., 2001, Dalack et al., 1998, Jeste et al., 1996), and negative social consequences (Agerbo et al., 2004).
The reproductive pattern of a patient after psychotic disorder onset may also be considered an outcome measure. Men and women becoming parents have been shown to form a population segment that, among others, has a lower risk of cancer (Dalton et al., 2004) and psychiatric disorders (Munk-Olsen et al., 2006). Several studies have found reduced fertility rates among persons with schizophrenia or a combined measure of psychosis (McGrath et al., 1999, Haukka et al., 2003, Howard et al., 2002, Svensson et al., 2007, Bhatia et al., 2004), with only one recent study showing an opposite result (Nimgaonkar et al., 1997). A study detected no reduced fertility rates in patients with bipolar disorder (affective psychosis) (MacCabe et al., 2009). However, many of these studies are flawed because they have not duly considered the dimensions of ‘how’ and ‘when’ to measure reproduction. The average age at which schizophrenia sets in is in the early 20s, while bipolar disorders set in later (Laursen et al., 2007a). Common for the two disorders, and for many other psychiatric disorders, is that disease strikes during the primary reproductive period of both men's and women's lives. It should therefore be taken into account how many (if any) children the person has before disorder onset. Furthermore, women with psychotic disorders are often advised not to have children (Viguera et al., 2002a) and they may choose to have an induced abortion. The rates of induced abortion in women with psychotic disorders should therefore also be taken into account as a possible explanation for their reduced fertility.
The aim of the present study was to examine reproductive patterns following psychotic disorder onset by comparing the rates of childbirths in patients with schizophrenia and bipolar disorder with those of other psychiatric patients and members of the general population who had not been admitted to a psychiatric hospital, taking into account parental status at the time of onset of the disorder, time since onset of the disorder, and the possible effect of abortions.
Section snippets
Methods
We established a cohort study and obtained data on the vital status of the cohortees and their children. Information was drawn from the Danish Civil Registration System (Pedersen et al., 2006). We linked this information to the Danish Psychiatric Central Register (Munk-Jorgensen and Mortensen, 1997) from where we obtained information on inpatient psychiatric treatment, and to the The Danish National Hospital Register (Andersen et al., 1999) from where we obtained information about induced
Results
In the follow-up period from 1970 to 2006, a total of 2,819,941 cohort members were followed for 34,898,001 person-years during which 1,587,709 persons had at least one child.
Firstly, we examined the IRRs of having the first child among cohort members with no children and found that men (IRR = 0.10; 95% CI (0.09, 0.11)) and women (IRR = 0.18; 95% CI (0.17, 0.20)) with schizophrenia had the lowest observed fertility compared with their respective counterparts with no psychiatric admission (Table 1).
Key findings
We found a reduced fertility among both women and men with psychiatric disorders. Persons with schizophrenia had the lowest fertility followed by bipolar disorder, unipolar disorder, and the remaining disorders. The reduced fertility was most pronounced among cohortees with a psychiatric disorder when having the first child was used as the outcome. Furthermore, reproductive rates rose with time since the first psychiatric admission, and men with a psychiatric disorder had a lower fertility than
Conclusion
Drawing on the entire Danish population, we were able to describe reproductive patterns in patients with psychotic disorders. Fertility rates among persons with a psychiatric disorder are highly dependent on diagnosis. Compared with the part of the population with no psychiatric hospitalization, persons with schizophrenia had the lowest rates of childbirths. Persons with bipolar disorder had lower rates than persons with unipolar disorder and persons in the group consisting of the remaining
Role of funding source
The Stanley Medical Research Institute and The Danish Medical Research Council had no further role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.
Contributors
Dr. Thomas Munk Laursen (TML) designed the study and wrote the protocol. Authors TML and Trine Munk-Olsen managed the literature searches and analyses. Author TML undertook the statistical analysis, and author TML wrote the first draft of the manuscript. All authors contributed to and have approved the final manuscript.
Conflict of interest
None.
Acknowledgments
This study was supported by The Stanley Medical Research Institute. Dr. T Munk-Olsen has received financial support from The Danish Medical Research Council (Reference number: 09-063642/FSS).
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2020, Schizophrenia ResearchCitation Excerpt :The first and principal limitation is the small size of our sample. Children with a parent or sibling diagnosed with schizophrenia are difficult to recruit, particularly in the young age range of our sample, due to issues such as reduced fecundity in patients and the disorganization of families as a result of the illness (Laursen and Munk-Olsen, 2010; Power et al., 2013). Given our small sample size, we suggest that our results are taken as preliminary evidence of abnormal STG functional connectivity in pre-adolescent children with a familial vulnerability for schizophrenia.
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Dr. TM Laursen had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analyses.
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This study was approved by the Danish Data Protection Agency.