Clinical Trials of Three Non-Drug Treatments for Winter Depression (SAD)

The treatments we are investigating include bright light therapy upon awakening, and two contrasting treatments during the final hours of sleep: negative air ionization (provided at two levels) and dawn simulation (also at two levels), both switched on by a silent electronic timer or microprocessor. We hypothesize that the reduced outdoor light availability in winter, as well as reduced concentration of negative ions in the air circulation are both factors that contribute to depression. By supplementing the indoor environment with either ions or light, we are aiming to recreate summer-like conditions that are therapeutic. Our past studies have shown all three methods to have antidepressant effects in patients with seasonal affective disorder (SAD). Unlike light therapy, negative air ionization is imperceptible (you cannot sense when the ionizer is active).

Applications to the program are accepted and reviewed throughout the year. Screening interviews for entry into the program are scheduled between August and February. Patients and researchers both benefit most when applications are received by the start of the individual's "problem season," because this leaves maximum time to explore alternate treatments. Candidates undergo a two-hour personal interview at Columbia-Presbyterian Medical Center that ascertains whether they meet inclusion criteria. At a second two-hour visit we provide a standard medical examination including blood tests, urinalysis and EKG, all without cost. As an alternative, physicals may be performed by one's personal physician. Once the study is underway, there are about five additional one-hour appointments for clinical evaluations, flexibly scheduled during the business day, usually about 10 days apart.

We provide the treatment apparatus on loan. All treatments are scheduled in the morning around the time of awakening. The bedroom treatments (negative ions or dawn simulation) end by the time of awakening. The bright light treatment takes place for half an hour after waking up. Initially, patients are randomly assigned to one of the treatment groups. The treatment must be taken consistently for three weeks at the same time every day, after which it is temporarily suspended to determine whether symptoms return. Given sufficient time within the winter season, patients then have the opportunity to try one of the alternate treatments to determine which works best for them. This provides an informed, confident basis for a treatment plan for subsequent years.

As part of the protocol, patients provide saliva samples on two evenings, which are used to test for the level of melatonin, a hormone that becomes active at night. Results reveal whether a person's internal circadian rhythm is early, late or normal, information that can be used to guide the timing of future treatment. This constitutes a distinct benefit for research participants, since such a diagnostic test is not yet available in medical practice.