Impact of sunlight on the age of onset of bipolar disorder


Michael Bauer, Charite University Medicine Berlin
Tasha Glenn, ChronoRecord Association Inc.
Martin Alda, McGill University
Ole A. Andreassen, Oslo University Hospital and Institute of Clinical Medicine
Raffaella Ardau, University-Hospital of Cagliari
Frank Bellivier, FondaMental Fondation
Michael Berk, Deakin University
Thomas D. Bjella, Oslo University Hospital
Letizia Bossini, University of Siena School of Medicine
Maria Del Zompo, University of Cagliari
Seetal Dodd, Deakin University
Andrea Fagiolini, University of Siena School of Medicine
Mark A. Frye, Mayo Clinic
Ana Gonzalez-Pinto, University of the Basque Country
Chantal Henry, Universite Paris
Flavio Kapczinski, Federal University of Rio Grande do Sul
Sebastian Kliwicki, Poznan University of Medical Science
Barbara Konig, BIPOLAR Zentrum Wiener Neustadt
Mauricio Kunz, Federal University of Rio Grande do Sul
Beny Lafer, Massachusetts General Hospital
Carlos Lopez-Jaramillo, Universidad de Antioquia
Mirko Manchia, Dalhousie University
Wendy K. Marsh, University of Massachusetts Medical SchoolFollow
Monica Martinez-Cengotitabengoa, University of the Basque Country
Ingrid Melle, Oslo University Hospital
Gunnar Morken, The Norwegian University of Science and Technology
Rodrigo A. Munoz, University of California San Diego
Fabiano G. Nery, University of Sao Paulo Medical School
Claire O'Donovan, Dalhousie University
Andrea Pfennig, Technische Universitat Dresden
Danilo Quiroz, Clinicas PsicoMedica Research Group
Natalie L. Rasgon, Stanford University School of Medicine
Andreas Reif, Cardiff University
Janusz Rybakowski, Poznan University of Medical Science
Kemal Sagduyu, University of Missouri Kansas City School of Medicine
Christian Simhandl, BIPOLAR Zentrum Wiener Neustadt
Carla Torrent, University of Barcelona
Eduard Vieta, University of Barcelona
Mark Zetin, Chapman University
Peter C. Whybrow, University of California Los Angeles

UMMS Affiliation

Department of Psychiatry

Publication Date


Document Type



Adolescent; Adult; Age of Onset; Aged; Aged, 80 and over; Bipolar Disorder; Female; Geography, Medical; Humans; Male; Middle Aged; *Photoperiod; Retrospective Studies; Seasons; *Solar Energy; *Sunlight


Mental and Social Health | Psychiatry | Psychiatry and Psychology


OBJECTIVE: Although bipolar disorder has high heritability, the onset occurs during several decades of life, suggesting that social and environmental factors may have considerable influence on disease onset. This study examined the association between the age of onset and sunlight at the location of onset.

METHOD: Data were obtained from 2414 patients with a diagnosis of bipolar I disorder, according to DSM-IV criteria. Data were collected at 24 sites in 13 countries spanning latitudes 6.3 to 63.4 degrees from the equator, including data from both hemispheres. The age of onset and location of onset were obtained retrospectively, from patient records and/or direct interviews. Solar insolation data, or the amount of electromagnetic energy striking the surface of the earth, were obtained from the NASA Surface Meteorology and Solar Energy (SSE) database for each location of onset.

RESULTS: The larger the maximum monthly increase in solar insolation at the location of onset, the younger the age of onset (coefficient= -4.724, 95% CI: -8.124 to -1.323, p=0.006), controlling for each country's median age. The maximum monthly increase in solar insolation occurred in springtime. No relationships were found between the age of onset and latitude, yearly total solar insolation, and the maximum monthly decrease in solar insolation. The largest maximum monthly increases in solar insolation occurred in diverse environments, including Norway, arid areas in California, and Chile.

CONCLUSION: The large maximum monthly increase in sunlight in springtime may have an important influence on the onset of bipolar disorder.

DOI of Published Version



Bipolar Disord. 2012 Sep;14(6):654-63. doi: 10.1111/j.1399-5618.2012.01025.x. Link to article on publisher's site

Journal/Book/Conference Title

Bipolar disorders

Related Resources

Link to Article in PubMed

PubMed ID