Seasonality is associated with anxiety and depression: The Hordaland health study

Oyane, Nicolas M.F.; Bjelland, Ingvar; Pallesen, Ståle; Holsten, Fred; Bjorvatn, Bjørn

doi:10.1016/j.jad.2007.05.002

« Previous Next »Journal of Affective Disorders
Volume 105, Issue 1 , Pages 147-155, January 2008

Seasonality is associated with anxiety and depression: The Hordaland health study

Nicolas M.F. Oyane
- Department of Public Health and Primary Health Care, University of Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Norway
- Corresponding author. Department of Public Health and Primary Health Care, University of Bergen, Kalfarveien 31, 5018 Bergen, Norway. Tel.: +47 93834962.
Ingvar Bjelland
- Department of Child and Adolescent Mental Health Services, Haukeland University Hospital, Norway
Ståle Pallesen
- Department of Psychosocial Science, University of Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Norway
Fred Holsten
- Department of Psychiatry, University of Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Norway
Bjørn Bjorvatn
- Department of Public Health and Primary Health Care, University of Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Norway

Received 25 February 2007; received in revised form 2 May 2007; accepted 3 May 2007.

Abstract

Background

The purpose of this study was to assess how seasonal changes in mood and behaviour were associated with depression and anxiety symptoms in a sample from a general population, and to investigate how prevalence figures were affected by month of questionnaire completion.

Methods

The target population included all individuals in the Hordaland county (Norway) born 1953–57 (N=29,400). In total, 8598 men (57% response rate) and 9983 women (70% response rate) attended the screening station. Half of the men (randomly chosen) and all of the women were offered a questionnaire to fill in with items on seasonality. This was measured using the Global Seasonality Score (GSS), a central component of the Seasonal Pattern Assessment Questionnaire (SPAQ). The Hospital Anxiety and Depression Scale (HADS) was used to measure anxiety and depression. Both questionnaires were completed by 2980 men (68.9%) and 8074 women (80.9%).

Results

Seasonality was positively associated with levels of both anxiety and depression regardless of the season the interview took place. In subjects with a low/moderate degree of seasonality there were modestly higher levels of depressive symptoms during November through March than the other months.