[Show abstract][Hide abstract] ABSTRACT: The purposes of this study were to evaluate the long-term stability of a seasonal pattern of recurrent depression, identify possible factors associated with alteration of the seasonal pattern, and determine whether atypical vegetative symptoms during early seasonal depressive episodes predict future seasonal relapses.
The subjects were 41 patients satisfying the criteria used in the Japanese multicenter study of seasonal affective disorder who were consistently treated at the same outpatient clinic. Their longitudinal courses were evaluated by using case records and the Schedule for Affective Disorder and Schizophrenia--Life-time Version; the mean follow-up period was 10.4 years.
Nine subjects (22.0%) consistently showed a fall-winter pattern of recurrence throughout follow-up. Seventeen patients with an initial fall-winter pattern subsequently tended to shift seasons or show less seasonality. This alteration in pattern was possibly associated with antidepressant therapy or life events. Eleven patients with an initial diagnosis of nonseasonal affective disorder subsequently developed seasonal affective disorder; no specific factors were associated with this change. Atypical vegetative symptoms were significantly more common in patients with stable seasonal patterns of recurrence than in those who lost seasonality.
Although seasonal affective disorder appeared to be altered by antidepressant treatment, the presence of a core group of patients with a consistent seasonal pattern of recurrent depression suggests the validity of seasonal affective disorder as a distinct subtype of recurrent affective illness. The findings also suggest that atypical vegetative symptoms during early seasonal depressive episodes predict the subsequent seasonality of depression.
No preview · Article · Jul 1995 · American Journal of Psychiatry
[Show abstract][Hide abstract] ABSTRACT: A nationwide survey of seasonal affective disorder (SAD) was performed from autumn 1990 to spring 1991 with the cooperation of 53 outpatient university psychiatric clinics in Japan. Forty-six SAD patients were identified among 5265 depressed outpatients. SAD was generally reported to occur in 1-3% of the depressed outpatients newly attending each facility. Hours of sunshine were found to be a more relevant variable influencing the prevalence of SAD than latitude or the mean temperature in December. The unexpectedly low percentage (20-30%) of SAD patients with atypical vegetative symptoms suggests that SAD patients who have no prior knowledge of SAD and those who are recruited via the media have different vegetative symptom profiles.
No preview · Article · May 1993 · Acta Psychiatrica Scandinavica