Summary: Researchers identified that fewer teenage boys commit suicide in regions of Sweden where bipolar diagnoses are more common. This discovery highlights the potential of more proactive care in reducing suicides.
The study found that suicide rates among boys were nearly 5% lower in regions with the highest bipolar diagnoses compared to those with the fewest. This suggests that suicide rates could be reduced through improved bipolar disorder diagnosis and treatment.
Bipolar disorder typically presents between the ages of 12 and 25 and is often associated with high suicide risk.
The study found a significant correlation between regions with a higher number of population-adjusted bipolar diagnoses and lower suicide rates among boys.
Improved bipolar disorder diagnosis and treatment could potentially help reduce the suicide rate among teenage boys in Sweden.
Source: Karolinska Institute
Bipolar disorder underlies roughly five percent of all suicides among young people. Previous studies also show that there is often a long delay between the onset of bipolarism and its correct diagnosis and treatment.
Researchers at Karolinska Institutet now show that fewer boys commit suicide in Swedish regions where bipolar diagnoses are more common.
The study, which is published in JAMA Psychiatry, could contribute to more proactive care for reducing the number of suicides.
“Bipolar disorder is often more distressing for people who develop it early in life and is one of the psychiatric disorders most associated with suicide risk,” says the study’s first author Peter Andersson, doctoral student at the Department of Clinical Neuroscience, Karolinska Institutet.
The disease usually manifests between the ages of 12 and 25 and is characterised by recurring episodes of mania and depression. Previous studies have shown that it can take up to six years for bipolar disorder to be diagnosed and treated, and comparisons with data from previous large-scale prevalence studies, indicate that under-diagnosis in Sweden is high among individuals aged 15-19.
Large regional differences
Using registry data from all of Sweden’s 21 regions between 2008 and 2021, researchers from Karolinska Institutet examined regional differences in the number of people aged 15 to 19 diagnosed with bipolar disorder and the correlation between population size-adjusted diagnoses and confirmed suicides for males and females.
The results, which included 585 confirmed suicides in this age group, showed large regional differences in the percentage of young people diagnosed with bipolar disorder.
The study also found an association between a higher number of population-adjusted bipolar diagnoses and lower suicide rates among boys.
“Our results show that the suicide rate among boys is almost five per cent lower in the regions that make most bipolar diagnoses than in those that make the fewest,” says corresponding author Adrian E. Desai Boström, resident in child and adolescent psychiatry in Stockholm and postdoc researcher at the Department of Clinical Neuroscience, Karolinska Institutet.
“This suggests that suicide among teenage boys in Sweden could be reduced with improvements to the diagnosis of bipolarism and its treatment.”
Sometimes wrongly diagnosed
The study’s complementary analyses showed that the relationship between the number of bipolar diagnoses and lower suicide rates among boys was independent of the number of care episodes and diagnoses of depression or schizophrenia.
Although the number of prescriptions for the mood stabilizer lithium paradoxically decreased when more bipolar diagnoses were established, increases were observed in the number of boys who received lithium at least once.
The researchers hypothesised that this could be interpreted as indicating that boys with bipolar disorder often begin lithium therapy but then switch to other mood-stabilising drugs for various reasons.
The researchers also see a possible risk that misguided treatment could lead to a higher suicide rate rather than no treatment at all.
“For example, some young people might be passed on by the psychiatric services to the social services under the provisions of laws relating to the care of the young and people with functional impairments,” says Andersson.
“We also know that bipolar patients are sometimes wrongly diagnosed with ‘normal’ depression.”
In a recently published study in Nature Communications the researchers found large regional differences in the use of advanced psychiatric treatments in child and adolescent psychiatry in Sweden.
They now plan to further investigate the effects of advanced psychiatric treatments on young people with bipolar disorder and other serious psychiatric conditions.
The study was a collaboration among researchers at Karolinska Institutet, Uppsala University, Umeå University, Lund University, Region Halland, and Region Stockholm in Sweden and was financed by the Swedish Research Council.
Co-author Jussi Jokinen has been part of an advisory committee for the pharmaceutical company Janssen on the use of esketamine in the treatment of depression. No other conflicts of interest have been reported.
Association of Bipolar Disorder Diagnosis With Suicide Mortality Rates in Adolescents in Sweden
The association of early diagnosis and management of bipolar disorder with adolescent suicide mortality (ASM) is unknown.
To assess regional associations between ASM and bipolar disorder diagnosis frequencies.
Design, Setting, and Participants
This cross-sectional study investigated the association between annual regional ASM and bipolar disorder diagnosis rates in Swedish adolescents aged 15 to 19 years in January 1, 2008, through December 31, 2021. Aggregated data without exclusions reported at the regional level encompassed 585 suicide deaths, constituting 588 unique observations (ie, 21 regions, 14 years, 2 sexes).
Bipolar disorder diagnosis frequencies and lithium dispensation rates were designated as fixed-effects variables (interaction term in the case of males). An interaction term between psychiatric care affiliation rates and the proportion of psychiatric visits to inpatient and outpatient clinics constituted independent fixed-effects variables. Region and year comprised random intercept effect modifiers. Variables were population adjusted and corrected for heterogeneity in reporting standards.
Main Outcomes and Measures
The main outcomes were sex-stratified, regional, and annual ASM rates in adolescents aged 15 to 19 years per 100 000 inhabitants as analyzed using generalized linear mixed-effects models.
Female adolescents were diagnosed with bipolar disorder almost 3 times more often than male adolescents (mean [SD], 149.0 [19.6] vs 55.3 [6.1] per 100 000 inhabitants, respectively). Median regional prevalence rates of bipolar disorder varied over the national median by a factor of 0.46 to 2.61 and 0.00 to 1.82 in females and males, respectively. Bipolar disorder diagnosis rates were inversely associated with male ASM (β = −0.00429; SE, 0.002; 95% CI, −0.0081 to −0.0004; P = .03) independent of lithium treatment and psychiatric care affiliation rates. This association was replicated by β-binomial models of a dichotomized quartile 4 ASM variable (odds ratio, 0.630; 95% CI, 0.457-0.869; P = .005), and both models were robust after adjusting for annual regional diagnosis rates of major depressive disorder and schizophrenia. No such association was observed in females.
Conclusions and Relevance
In this cross-sectional study, lower suicide death rates in adolescent males was robustly associated with regional diagnosis rates of bipolar disorder at an estimated magnitude of approximately 4.7% of the mean national suicide death rate. The associations could be due to treatment efficacy, early diagnosis and management, or other factors not accounted for.