Michael A. Young

The temporal onset of individual symptoms in winter depression: differentiating underlying mechanisms

The transition from well to depressed offers a window to the mechanisms which underlie depressive symptoms. We examined the onset of each of 15 symptoms in 53 patients with winter depression. Three symptoms had a risk of onset closely associated with the onset of the episode itself and may represent a core syndrome. The risk of onset for the remaining symptoms was unrelated to the onset and the course of the episode. The symptoms were equally likely to begin at any time during the episode and suggest a different pathological mechanism. A dual vulnerability hypothesis is proposed; research and treatment implications are discussed.

An item-response theory evaluation of the Beck Hopelessness Scale

Hopelessness is an important clinical symptom for both theoretical and practical reasons. The Hopelessness Scale of Beck and colleagues was constructed to measure this construct, but has had no psychometric assessment since its original development. We conducted an evaluation of the scale using item-response theory. Results in two separate samples were nearly identical. The Hopelessness Scale was found to be unidimensional with strong item—construct relationships. However, it was relatively insensitive at lower levels of hopelessness.

Lack of stability of the RDC endogenous subtype in consecutive episodes of major depression

The stability of the endogenous subtype of major depressive disorder was examined within individuals across consecutive episodes. The subjects were 119 probands from the NIMH Collaborative Depression Study who experienced at least two episodes of unipolar major depressive disorder within a two-year period of biannual evaluations. Structured data collection methods and Research Diagnostic Criteria were employed. The inter-episode stability of subtype diagnosis was low, never producing a kappa of greater than 0.25. This result was not attributable to threshold for diagnosis, time between episodes, differences in severity, or changes in raters.

Concordance of symptoms in recurrent depressive episodes

The presence or absence of 12 depressive symptoms was examined in 93 bipolar and 108 unipolar patients who had two discrete episodes of major depression over a 5-year period. For each symptom the concordance of its presence or absence across episodes was low. The agreement observed was largely that to be expected by chance. A substantial amount of concordance was obtained if differences in episode intensity (propensity to have symptoms) were taken into account. This suggests that although there may be factors related to depression which remain stable across episodes, symptom presentation is moderated by other factors, such as intensity, which vary from episode to episode.

26 – A Comparison of Two Different Placebo-Controlled SAD Light Treatment Studies

Abstract High intensity light is widely used as an antidepressant for the treatment of winter depression. There is no doubt that treatment with light can substantially reduce and even eliminate all symptoms. However, establishing that this effect is greater than what could be produced by a placebo-control treatment is hampered by the difficulty in finding an appropriate placebo for light treatment. This paper compares two light treatment studies with good placebo controls. The first study employed a crossover design between morning light and morning placebo. The second, which is still in progress, employs a parallel design with morning light, morning placebo and evening light groups. The first study did not show a statistically significant difference between light and placebo. Although the response rates in the second study are much greater than in the first study, there is still no significant difference between light and placebo. The response to light treatment is much greater than in the first study, but the response to placebo treatment is also much greater. Several possible reasons for the greater antidepressant effects in the second study are discussed, such as a larger placebo component in all three treatments due to a more optimistic staff. Although it would be premature to draw final conclusions about efficacy, we have shown that for light treatment, like antidepressant drug treatment, most of the antidepressant effect can be attributed to placebo effects.