Bipolar II disorder has the highest prevalence of seasonal affective disorder in early‐onset mood disorders: Results from a prospective observational cohort study

Abstract

Background: Many mood disorder patients experience seasonal changes in varying degrees. Studies on seasonality have shown that bipolar disorder has a higher prevalence rate in such patients; however, there is limited research on seasonality in early-onset mood disorder patients. This study estimated the prevalence of seasonality in early-onset mood disorder patients, and examined the association between seasonality and mood disorders. Methods: Early-onset mood disorder patients (n = 378; 138 major depressive disorder; 101 bipolar I disorder; 139 bipolar II disorder) of the Mood Disorder Cohort Research Consortium and healthy control subjects (n = 235) were assessed for seasonality with Seasonality Pattern Assessment Questionnaire (SPAQ).Results: A higher global seasonality score, an overall seasonal impairment score, and the prevalence of seasonal affective disorder (SAD) and subsyndromal SAD showed that mood disorder subjects had higher seasonality than the healthy subjects. The former subject group had a significantly higher mean overall seasonal impairment score than the healthy subjects (p < .001); in particular, bipolar II disorder subjects had the highest prevalence of SAD, and the diagnosis of bipolar II disorder had significantly higher odds ratios for SAD when compared to major depression and bipolar I disorder (p < .05).Conclusions: Early-onset mood disorders, especially bipolar II disorder, were associated with high seasonality. A thorough assessment of seasonality in early-onset mood disorders may be warranted for more personalized treatment and proactive prevention of mood episodes.

Differences between bipolar disorder types 1 and 2 support the DSM two-syndrome concept

“…In addition, BD-2 subjects were more prone to switch from depression to elevated mood in association with antidepressant treatment, consistent with their tendency to follow a DMI course and lesser likelihood of receiving mood-stabilizing agents. BD-2 subjects were less subject to seasonal variations than BD-1 subjects, unlike findings from a smaller recent study (Yeom et al 2021 ). The greater likelihood of having a cyclothymic temperament and a rapid-cycling course along with less seasonal changes may indicate that mood oscillations are more chaotic in BD-2 vs. BD-1 subjects.…”

Neurobiological and behavioral mechanisms of circadian rhythm disruption in bipolar disorder: A critical multi‐disciplinary literature review and agenda for future research from the ISBD task force on chronobiology

“…BD patients commonly show seasonal changes in mood, and SAD occurs more frequently in BD compared to MDD or community controls. One recent study suggested that compared to MDD and BD I, subjects with BD II were the most likely to show seasonal mood variation and disability 183 . Previous studies of seasonal BD have found association with clock gene variants.…”

“…One recent study suggested that compared to MDD and BD I, subjects with BD II were the most likely to show seasonal mood variation and disability. 183 Previous studies of seasonal BD have found association with clock gene variants. In a genetic association study of 269 BD patients (26% with SAD), the authors studied 349 SNPs and after correction for multiple testing, identified significant associations with five variants in NPAS2.…”

Bipolar Chronobiology in Men and Mice: A Narrative Review

“…Seasonal changes affect all patients with mood disorders, and seasonal affective symptoms occur more frequently in BD compared to MDD or community controls. Previous studies suggested that subjects with BD II were the most likely to show seasonal mood variation and disability compared to MDD and BD I [83]. Genome-wide association studies (GWAS) observed associations between seasonal BD and clock gene variants, especially with NPAS2, CSNK1E, and RORA [84,85].…”