Characteristics of patients with otherwise typical winter depression, but with incomplete summer remission

Seasonal affective disorder, winter depression type (WD-SAD), is characterized by recurring autumn/winter depression with full remission or hypomania/mania in summer. However, some patients have an otherwise typical WD but with incomplete summer remission. We wanted to elucidate in what other respects such patients differ from typical WD-SAD patients.

14 patients meeting DSM-III-R criteria for Seasonal Pattern except for incomplete summer remission (ISR), were compared with 144 patients meeting the full criteria, including complete summer remission (CSR), with regard to demography, illness history, clinical symptoms, and response to light treatment.

In comparison with the CSR group, the ISR group had a longer duration of illness, more often used antidepressants, and improved significantly less after treatment with bright light for 6 days, whereas the symptomatology in winter (Montgomery-Asberg Depression Rating Scale plus hypersomnia, hyperphagia, and carbohydrate craving) was similar in the two groups.

The ISR group was small, and the severity of their summer depression could only be assessed retrospectively.

Patients with otherwise typical WD but with incomplete summer remission respond poorly to light treatment. Full summer remission should be retained as a criterion for WD-SAD.