Bipolar Disorder with Seasonal Pattern: Clinical Characteristics and Gender Influences

Abstract

Bipolar disorder (BD) has a multifactorial etiology with heterogeneous clinical presentations. Around 25% of BD patients may present with a depressive seasonal pattern (SP). However, there are limited scientific data on the prevalence of SP, its clinical manifestations, and any gender influence. Four hundred and fifty-two BD I and II cases (62% female), recruited from three French university-affiliated psychiatric departments, were assessed for SP. Clinical, treatment, and sociodemographic variables were obtained from structured interviews. One hundred and two (23%) cases met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for SP, with similar frequency according to gender. Multivariate analysis showed a significant association between SP and BD II (odds ratio [OR] = 1.99, p = 0.01), lifetime history of rapid cycling (OR = 2.05, p = 0.02), eating disorders (OR = 2.94, p = 0.003), and total number of depressive episodes (OR = 1.13, p = 0.002). Seventy-one percent of cases were correctly classified by this analysis. However, when stratifying the analyses by gender, SP was associated with BD II subtype (OR = 2.89, p = 0.017) and total number of depressive episodes (OR = 1.21, p = 0.0018) in males but with rapid cycling (OR = 3.02, p = 0.0027) and eating disorders (OR = 2.60, p = 0.016) in females. This is the first study to identify different associations between SP and clinical characteristics of BD according to gender. The authors suggest that SP represents a potentially important specifier of BD. These findings indicate that seasonality may reflect increased severity or complexity of disorder.

A cross-sectional study of factors affecting seasonality in bipolar disorder

“…Confirming the findings of several previous studies [1,3,5] (with one excep tion), [7] we found that patients with BD are sensitive to seasonal changes. Patients experiencing seasonal changes require special attention because they may need modifications in pharmacological and behavioural management strategies, as recommended by one of these recent studies.…”

Comparison of sociodemographic and clinical characteristics of bipolar patients with and without seasonal patterns

“…Similar to our study, another study also found that the total number of episodes was higher in bipolar patients with seasonal patterns. 3,11 In our study, there was no difference in dominant bipolar type between those with and those without seasonal patterns. Although the data suggest that rates of seasonal patterns in BD II were much higher than in BD-I.…”

“…14 In our study, no other axis-I comorbidity was determined to be significant, despite eating disorders being determined significant in another study. 3 These results show us that bipolar patients with seasonal patterns have poorer prognoses than bipolar patients without seasonal patterns. [14][15][16][17][18][19] However, seasonality is not among the prognostic indicators of BD.…”

“…2 Seasonal patterns exist in mood disorders more frequently than in other psychiatric disorders. It has been reported that seasonal patterns may occur at a rate of 20-30%, particularly in bipolar patients (3). Although it is still not clear which episode type is more closely associated with which season, it has been reported that depressive episodes are more likely to occur between September and January, manic episodes between March and June, and mixed episodes between May and June, with hypomania showing a similar seasonal pattern to mania.…”

“…9 Some studies have also reported that seasonal patterns are seen more often in the bipolar II subtype and women, and the dominant episodes and first episodes of these patients are more likely to be of a depressive type. 3,10,11 Seasonal patterns are thought to be associated with some genetic factors. 12 There is a limited number of studies in our country on the prevalence of seasonal patterns in bipolar disorder (BD), its association with sociodemographic and clinical characteristics, and its effects on treatment.…”