Critical Reasoning

According to a review of 61 studies of patients suffering from severely debilitating depression, a large majority of the patients reported that missing a night's sleep immediately lifted their depression. Yet sleep-deprivation is not used to treat depression even though the conventional treatments, which use drugs and electric shocks, often have serious side effects.
Which of the following, if true, best explains the fact that sleep-deprivation is not used as a treatment for depression?
(A) For a small percentage of depressed patients, missing a night's sleep induces a temporary sense of euphoria.
(B) Keeping depressed patients awake is more difficult than keeping awake people who are not depressed.
(C) Prolonged loss of sleep can lead to temporary impairment of judgment comparable to that induced by consuming several ounces of alcohol.
(D) The dramatic shifts in mood connected with sleep and wakefulness have not been traced to particular changes in brain chemistry.
(E) Depression returns in full force as soon as the patient sleeps for even a few minutes.

I agree that most of the wrong choices in this question require additional information or an assumption to explain the paradox. However, the OA (E) also seems to require additional information. How can we know that the patients will sleep? We must know whether it i is possible that the patients sleep during the treatment.

Thanks!

metallicafan wrote:How can we know that the patients will sleep? We must know whether it i is possible that the patients sleep during the treatment.

The GMAT expects us to use common sense when we evaluate the answer choices.
No one can forgo sleep FOREVER.
At some point the sleep-deprived patients -- like ALL human beings -- will have to sleep.
According to the OA, their depression will return in full force as soon as they sleep for even a few minutes -- explaining why sleep-deprivation is not used to treat depression.