Seasonal affective disorder

Last reviewed: 23 Aug 2023
Last updated: 30 Jun 2022

Summary

Definition

History and exam

Key diagnostic factors

  • ≥2-year period of seasonally related changes in mood
  • fall or winter depression
  • spring or summer symptom remission
  • atypical depressive symptoms
  • vegetative depressive symptoms
  • spring or summer manic or hypomanic symptoms
  • spring or summer depression
  • manic/hypomanic symptoms
More key diagnostic factors

Other diagnostic factors

  • somatic symptoms
  • behavioral withdrawal
  • functional impairments
  • excessive alcohol use
  • tachycardia
  • increased systolic blood pressure
  • restlessness
Other diagnostic factors

Risk factors

  • exposure to diminished light during winter and increased light during summer
  • residing at a northern latitude
  • family history of seasonal affective disorder (SAD)
  • female sex
  • age 20 to 30 years
  • psychological factors (e.g., high neuroticism)
  • psychiatric comorbidity (e.g., anxiety, ADHD, premenstrual dysphoric disorders)
  • alcohol use
More risk factors

Diagnostic investigations

1st investigations to order

  • clinical exam
More 1st investigations to order

Investigations to consider

  • blood metabolic panel
  • serum thyroid-stimulating hormone
  • toxicology screen (urine and blood)
More investigations to consider

Treatment algorithm

ACUTE

subsyndromal SAD

SAD with recurrent, unipolar depressive disorder

SAD with bipolar mood disorder

ONGOING

prevention of SAD with unipolar mood disorder

prevention of SAD with bipolar mood disorder

Contributors

Authors

Craig N. Sawchuk, PhD
Craig N. Sawchuk

Associate Professor

Co-Chair, Division of Integrated Behavioral Health

Department of Psychiatry and Psychology

Mayo Clinic

Rochester

MN

Disclosures

CNS declares that he has no competing interests.

Jason P. Veitengruber, MD
Jason P. Veitengruber

Assistant Professor

Department of Psychiatry and Behavioral Sciences

University of Washington School of Medicine

Seattle

WA

Disclosures

JPV declares that he has no competing interests.

William B. Leasure, MD

Clinical Instructor

Department of Psychiatry and Psychology

Mayo Clinic

Rochester

MN

Disclosures

WBL declares that he has no competing interests.

Peer reviewers

Stephen Lurie, MD, PhD

Director of Assessment

Office of Curriculum and Assessment

University of Rochester School of Medicine and Dentistry

Rochester

NY

Disclosures

SL declares that he has no competing interests.

Dietmar Winkler, MD

Department of Psychiatry and Psychotherapy

Medical University of Vienna

Vienna

Austria

Disclosures

DW is an author of a number of references cited in this topic. DW declares that he has no competing interests.

  • Differentials

    • Major depressive disorder, single and recurrent episodes
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    More Differentials
  • Guidelines

    • Clinical guidelines for the management of major depressive disorder in adults
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