Table 6 Clinical features that help to distinguish depression and CFS/ME

Physical Exertion

Exercise can improve mood and energy levels overall

Nearly always causes delayed worsening of the fatigue and other symptoms

Mood

Low

Usually normal

Motivation

Reduced

Normal in the majority and in the absence of complicating depression

Sleep

Early morning wakening common but difficult initiating sleep also seen

Difficulty initiating sleep and getting up in the morning

Memory

Often rumination about the past and feelings of guilt

Word finding difficulty and precise recollection of recent events.

Concentration

If engaged can be normal

Impaired especially with extraneous noise and movement

Energy

Persistently low but with only minor day to day variability and no delayed post-exertion worsening

Variable from day to day and accompanied by delayed worsening with physical, mental and emotional exertion

Appetite

Low. Weight can go down.

Normal. Weight either maintained or sometimes increased.

Affect

One of sadness. Reduced spontaneity of action and of facial expression

Normal. Frustration and sometimes anger seen.

Interest in outside life

Reduced. No desire to complete previous hobbies or see family and friends

Maintained. Impaired energy reduces ability to continue with hobbies, social life and leisure activities.

Response to anti-depressants

Fatigue may be improved

Little or no response if no complicating depression and many are hypersensitive to normal starting doses.