WINTER SEASONAL AFFECTIVE-DISORDER - A FOLLOW-UP-STUDY OF THE FIRST 59 PATIENTS OF THE NATIONAL-INSTITUTE-OF-MENTAL-HEALTH SEASONAL STUDIESPROGRAM

Objective: The purpose of this study was to characterize the long-term course of patients with seasonal affective disorder. Method: The firs t 59 patients with winter seasonal affective disorder who had entered winter protocols were retrospectively followed up after a mean interva l of 8.8 years. Detailed life charts were constructed through use of a semistructured interview and collateral records. Results: The disorde r of 25 patients (42%) remained purely seasonal, with regular recurren ces of winter depression and no depression or treatment through any su mmer. The course of illness was complicated by varying degrees of nons easonal depression in 26 patients (44%). The disorders of eight patien ts (14%) had fully remitted. Certain features of the group with compli cated seasonal affective disorder suggested that they were more severe ly ill. Twenty-four patients (41%) continued to use light treatment re gularly throughout the follow-up period. Light treatment was preferred to medication for winter recurrences, although antidepressants had be en used in the winter by most (63%) of the patients who still used lig hts at follow-up. Conclusions: The pattern of winter depressions and s ummer remissions remained fairly persistent over time in this group of patients. The temporal distribution of depressive episodes both withi n and across individual patients was consistent with the results of se veral recent follow-up studies of seasonal affective disorder, providi ng support for the predictive and construct validity of the Rosenthal et al. diagnosis of winter seasonal affective disorder. Light treatmen t, while remaining a safe and satisfactory treatment for many, may be insufficient for more severely ill patients. The appearance of nonseas onal depressions in patients with winter seasonal affective disorder m ay be associated with greater severity of illness and less responsiven ess to light treatment.