Recent systematic review s have shown that  light therapy  is an efficacious and well-tolerated treatment for SAD .
There is also evidence for efficacy of pharmacotherapy to treat and prevent SAD .
SAD is a common condition with significant psychosocial impairment .
BACKGROUND Seasonal affective disorder ( SAD ) consists of recurrent major depressive episodes in the fall/winter with remissions in spring/summer .
RESULTS A careful history is important to make the diagnosis and differentiate SAD from other similar conditions such as subsyndromal SAD and atypical depression .
Seasonal patterns with winter worsening are also recognized in " nonseasonal " depression as well as many other psychiatric conditions , and comorbidity with SAD is common .
The pathophysiology of SAD seems to be heterogeneous as research on circadian , neurotransmitter function and genetic hypotheses have shown discrepant results .
A dual vulnerability model with differential loading on separate seasonal and depression factors has been proposed to explain these findings .
Cognitive-behavioral therapy, light therapy, and their combination in treating seasonal affective disorder.
BACKGROUND The need to develop supplementary or alternative treatments for seasonal affective disorder ( SAD ) is underscored by the significant minority ( 47 % ) of SAD patients that is refractory to light therapy , the persistence of residual symptoms despite light treatment , and poor long-term compliance with light use . Because preliminary studies suggest that cognitive and behavioral factors are involved in SAD , cognitive-behavioral therapy ( CBT ) warrants investigation as a possible treatment option . METHODS We piloted a 6-week r and omized clinical trial to compare a st and ard light therapy protocol ; a novel , SAD-tailored , group CBT intervention ; and their combination in ameliorating and remitting a current SAD episode and as prophylaxis against episode recurrence . Depressive symptom severity and remission rates were assessed at post-treatment and at a 1-year follow-up visit to examine long-term treatment durability . RESULTS CBT , light therapy , and their combination all demonstrated significant reductions in depressive symptoms on two different outcome measures . Remission rates varied by measure , but did not reach statistical significance . During the subsequent winter , CBT , particularly in combination with light therapy , appeared to improve long-term outcome regarding symptom severity , remission rates , and relapse rates . No CBT-treated participant , with or without light , experienced a full SAD relapse compared to over 60 % of those treated with light alone . LIMITATIONS These results should be viewed as preliminary and are limited by the small sample size ( n=23 ) and lack of a control group . CONCLUSIONS The nearly half of SAD patients who do not remit with light alone may benefit from CBT as an adjunct or alternative treatment , especially as a prophylaxis against episode recurrence
Recent systematic review s have shown that  light therapy  is an efficacious and well-tolerated treatment for SAD .
There is also evidence for efficacy of pharmacotherapy to treat and prevent SAD .
SAD is a common condition with significant psychosocial impairment .
BACKGROUND Seasonal affective disorder ( SAD ) consists of recurrent major depressive episodes in the fall/winter with remissions in spring/summer .
RESULTS A careful history is important to make the diagnosis and differentiate SAD from other similar conditions such as subsyndromal SAD and atypical depression .
Seasonal patterns with winter worsening are also recognized in " nonseasonal " depression as well as many other psychiatric conditions , and comorbidity with SAD is common .
The pathophysiology of SAD seems to be heterogeneous as research on circadian , neurotransmitter function and genetic hypotheses have shown discrepant results .
A dual vulnerability model with differential loading on separate seasonal and depression factors has been proposed to explain these findings .