Evidence-Based Reviews

SAD: Is seasonal affective disorder a bipolar variant?

Current Psychiatry. 2010 February;9(2):43-54

Patients with seasonal bipolarity require different treatment from those with unipolar SAD

References

1. American Psychiatric Association. Diagnostic and statistical manual of mental disorders, 4th ed, text rev. Washington, DC: American Psychiatric Association; 2000.

2. Lam RW, Levitt AJ. eds. Clinical guidelines for the treatment of seasonal affective disorder. Vancouver, BC: Clinical and Academic Publishing; 1999.

3. Rosenthal NE, Sack DA, Gillin JC, et al. Seasonal affective disorder. A description of the syndrome and preliminary findings with light therapy. Arch Gen Psychiatry. 1984;41(1):72-80.

4. Michalak EE, Wilkinson C, Hood K, et al. Seasonal and nonseasonal depression: how do they differ? Symptom profile, clinical and family history in a general population sample. J Affect Disord. 2002;69(1-3):185-192.

5. Goodwin FK, Jamison KR. Manic-depressive illness: bipolar disorders and recurrent depression. 2nd ed. New York, NY: Oxford University Press; 2007.

6. Sohn CH, Lam RW. Treatment of seasonal affective disorder: unipolar versus bipolar differences. Curr Psychiatry Rep. 2004;6(6):478-485.

7. Goikolea JM, Colom F, Martinez-Aran A, et al. Clinical and prognostic implications of seasonal pattern in bipolar disorder: a 10-year follow-up of 302 patients. Psychol Med. 2007;37:1595-1599.

8. Kessler RC, Zhao S, Blazer DG, et al. Prevalence, correlates, and course of minor depression and major depression in the National Comorbidity Survey. J Affect Disord. 1997;45(1-2):19-30.

9. Modell JG, Rosenthal NE, Harriett AE, et al. Seasonal affective disorder and its prevention by anticipatory treatment with bupropion XL. Biol Psychiatry. 2005;58:658-667.

10. Cassidy F, Carroll BJ. Seasonal variation of mixed and pure episodes of bipolar disorder. J Affect Disord. 2002;68:25-31.

11. Shin K, Schaffer A, Levitt AJ, et al. Seasonality in a community sample of bipolar, unipolar and control subjects. J Affect Disord. 2005;86:19-25.

12. Wood J, Birmaher B, Axelson D, et al. Replicable differences in preferred circadian phase between bipolar disorder patients and control individuals. Psychiatry Res. 2009;166(2-3):201-209.

13. Soreca I, Frank E, Kupfer DJ. The phenomenology of bipolar disorder: what drives the high rate of medical burden and determines long-term prognosis? Depress Anxiety. 2009;26(1):73-82.

14. Terman M, Terman J, Rafferty B. Experimental design and measures of success in the treatment of winter depression by bright light. Psychopharmacol Bull. 1990;26(4):505-510.

15. Goel N, Terman M, Terman JS, et al. Summer mood in winter depressives: validation of a structured interview. Depress Anxiety. 1999;9:83-91.

16. Denicoff KD, Leverich GS, Nolen WA, et al. Validation of the prospective NIMH-Life-Chart Method (NIMH-LCM-p) for longitudinal assessment of bipolar illness. Psychol Med. 2000;30:1391-1397.

17. Ghaemi SN, Miller CJ, Berv DA, et al. Sensitivity and specificity of a new Bipolar Spectrum Diagnostic Scale. J Affect Disord. 2005;84:273-277.

18. Phelps J, Angst J, Katzow J, et al. Validity and utility of bipolar spectrum models. Bipolar Disord. 2008;10:179-193.

19. Williams JB, Link MJ, Rosenthal NE, et al. Structured Interview Guide for the Hamilton Depression Rating Scale - Seasonal Affective Disorder Version (SIGH-SAD). New York, NY: New York State Psychiatric Institute; 1992.

20. Wu JC, Kelsoe JR, Schachat C, et al. Rapid and sustained antidepressant response with sleep deprivation and chronotherapy in bipolar disorder. Biol Psychiatry. 2009;66(3):298-301.

21. Golden RN, Gaynes BN, Ekstrom RD, et al. The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence. Am J Psychiatry. 2005;162(4):656-662.

22. Terman M, Terman JS, Ross DC. A controlled trial of timed bright light and negative air ionization for treatment of winter depression. Arch Gen Psychiatry. 1998;55(10):875-882.

23. Eastman CI, Young MA, Fogg LF, et al. Bright light treatment of winter depression: a placebo-controlled trial. Arch Gen Psychiatry. 1998;55(10):883-889.

24. Lewy AJ, Bauer VK, Cutler NL, et al. Morning vs evening light treatment of patients with winter depression. Arch Gen Psychiatry. 1998;55(10):890-896.

25. Sit D, Wisner KL, Hanusa BH, et al. Light therapy for bipolar disorder: a case series in women. Bipolar Disord. 2007;9:918-927.

26. Goodwin GM. Evidence-based guidelines for treating bipolar disorder: revised second edition—recommendations from the British Association for Psychopharmacology. J Psychopharmacol. 2009;23(4):346-388.

27. Lam RW, Levitt AJ, Levitan RD, et al. The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder. Am J Psychiatry. 2006;163:805-812.

28. Pjrek E, Konstantinidis A, Assem-Hilger E, et al. Therapeutic effects of escitalopram and reboxetine in seasonal affective disorder: a pooled analysis. J Psychiatr Res. 2009;43(8):792-797.

29. Moscovitch A, Blashko CA, Eagles JM, et al. A placebo-controlled study of sertraline in the treatment of outpatients with seasonal affective disorder. Psychopharmacology (Berl). 2004;171(4):390-397.

30. Rohan KJ, Roecklein KA, Tierney Lindsey K, et al. A randomized controlled trial of cognitive-behavioral therapy, light therapy, and their combination for seasonal affective disorder. J Consult Clin Psychol. 2007;75(3):489-500.

31. Rohan KJ. Coping with the seasons: a cognitive-behavioral approach to seasonal affective disorder. Therapist guide. New York, NY: Oxford University Press; 2008.

32. Rohan KJ, Roecklein KA, Lacy TJ, et al. Winter depression recurrence one year after cognitive-behavioral therapy, light therapy, or combination treatment. Behav Ther. 2009;40(3):225-238.

33. Frank E, Kupfer DJ, Ehlers CL, et al. Interpersonal and social rhythm therapy for bipolar disorder: integrating interpersonal and behavioral approaches. Behavior Therapist. 1994;17:143-149.

34. Frank E, Kupfer DJ, Thase ME, et al. Two-year outcomes for interpersonal and social rhythm therapy in individuals with bipolar I disorder. Arch Gen Psychiatry. 2005;62(9):996-1004.

Discuss this article

Ms. S, age 24, is referred to our team in early December by her primary care physician for “fatigue.” The patient describes going to bed and falling asleep before 9:30 these winter evenings, whereas in summer she went to bed at 11 PM. She craves bread, pasta, and sweets and reports increased appetite in winter compared with summer. Her mood is low, and she misses warm-weather activities of gardening and walking. Fatigue and difficulty concentrating are causing her problems at work and school.

Her history reveals mood elevation in spring as days become longer, with a clear change at approximately March 10 to 20. She reports “spring fever” and feeling “great” last year as soon as daylight saving time began. She slept only 3 hours a night and had a burst of ideas to expand her small business. She threw herself into her work, feeling she was making up for lost time and productivity. She also admits to making a large, misguided business investment during that time.

Upon questioning, she recalls that the previous spring she argued with her father and threw a cup of hot tea at him. When interviewed, Ms. S’s mother describes her daughter at that time as having “a very short fuse,” speaking loud and fast, staying up late at night, and looking as though she was not herself.

Seasonal affective disorder (SAD) is an umbrella term for mood disorders that follow a seasonal pattern of recurrence. Bipolar I disorder (BD I) or bipolar II disorder (BD II) with seasonal pattern (BD SP) is the DSM-IV-TR diagnosis for persons with depressive episodes in the fall or winter and mania (BD I) or hypomania (BD II) in spring or summer ( Table 1 ).¹

This article compares BD SP with major depressive disorder with seasonal pattern (MDD SP), in which depressive episodes usually occur in fall or winter and fully remit in spring or summer.¹ Rather than being categorically distinct from each other, BD SP and MDD SP may represent extreme variants on a seasonal depression continuum from unipolar to bipolar.

Table 1

DSM-IV-TR criteria for seasonal pattern specifier*

A	A regular pattern of major depressive episodes (MDEs) at a particular time of year (such as fall and/or winter)
B	Full remission or change to mania or hypomania at a particular time of year (such as spring or summer)
C	2 seasonal MDEs that followed the pattern described in (A) and (B) occurred in the past 2 years (and no nonseasonal MDEs)
D	Seasonal MDEs substantially outnumber nonseasonal MDEs across the lifespan
Cases do not meet criteria if: seasonal episodes have not been present in the past 2 consecutive winters because individuals have been successfully treated or have lived or traveled in southern locations, despite the expectation that continuing treatment is needed and/or a return to northern locales would precipitate another seasonal episode an obvious psychosocial stressor related to the mood change recurs on a seasonal basis (such as regular winter unemployment, holiday depression, anniversary reactions)
*Can be applied to a pattern of major depressive episodes in bipolar I disorder, bipolar II disorder, or major depressive disorder
Source: Adapted from reference 1

Overlap of MDD SP and BD SP

Clinical Point

Cases do not qualify for a seasonal pattern specifier if a psychosocial stressor related to the mood change recurs on a seasonal basis

The seasonal pattern specifier can be applied to a diagnosis of MDD, BD I, or BD II.¹ Seasonality-focused assessments, described below, can help characterize seasonal patterns that do not meet full SP criteria but may deserve clinical attention.

Symptom presentation. MDD SP and BD SP share similar atypical depressive symptom presentations and seasonal recurrence patterns ( Box 1 ). Hypersomnia, hyperphagia, and psychomotor retardation are more prevalent in major depressive episodes of bipolar disorders and SAD than in unipolar or nonseasonal mood disorders.^2-4 Individuals with SAD also report fatigue and decreased physical activity,³ both of which are characteristic of bipolar depressive episodes.⁵

Although psychosis and psychiatric hospitalizations are more common in BD I than unipolar disorders,⁶ individuals with BD SP are less likely to report psychosis than those with nonseasonal BD.⁷ Another study found that BD SP patients reported a higher rate of psychiatric hospitalizations than MDD SP patients (28% vs 9.4%).⁶

Recurrence pattern. Major depressive episodes are highly recurrent in both MDD and BD, with or without a seasonal pattern. Approximately 75% of individuals with MDD experience ≥1 recurrence (mean, 10.8 episodes);⁸ MDD SP patients report a mean of 13.4 episodes.⁹ The mean lifetime episodes in BD SP is 20.74, compared with 11.67 in nonseasonal BD.⁷