Part front matter for Section 10 Restlessness

Restlessness is characterized by excessive purposeless or semi-purposeful voluntary activity. It may take the form of fiddling with objects and body parts, or making unnecessary limb movements, including tensing muscles, squeezing the hands, swinging the legs, crossing and uncrossing the knees, and shuffling the feet. It can also produce shifting of body position when lying or sitting and in more extreme forms may result in rising and pacing about. Often the same sequence of movements is repeated over and over again. Restlessness is usually, although not always, accompanied by feelings of inner tension and stress.

Restlessness is non-specific and results from a number of causes (Table 1). It is a normal response to psychological stress and is part of the ‘flight or fight’ reaction. In addition, it may be part of a number of psychiatric disorders, including anxiety states, agitated depression, hypomania, and mania. In these cases there is usually evidence of agitation in addition to the excessive motor activity.

Restlessness is also frequently encountered in organic brain disorders, especially in association with delirium. It is thus seen in delirium tremens, high fever, metabolic disturbances, and infections involving the brain. Impaired mentation, delusions, and hallucinations are accompanying features. It may occur after head injury and it is usually associated with difficulty with concentration and memory.

Restlessness can also result from severe pain. Some pains force the sufferer to lie still, particularly if movement aggravates the discomfort. Other types of pain may cause the person to toss, turn, roll about, or rise and restlessly pace.

Severe physical illness, even if unaccompanied by delirium or pain, can result in restlessness. Thus pulmonary oedema, marked bronchospasm, respiratory failure, and the like may be associated with unnecessary physical activity, including picking at the bedclothes and pushing things away. Usually such movement is restricted to the upper limbs.

Restless activity may result from administration of stimulant drugs, including amphetamines. This often involves locomotion

and such reactions are frequently accompanied by abnormal mental states, including hallucinations.

By and large, the above excessive movements are non-specific responses to a variety of mental and physical states and are not dealt with in the remainder of this section. Further discussion is limited to akathisia, restless legs syndrome (with periodic movements of sleep) and painful legs and moving toes. In akathisia there is a subjective inner sense of restlessness and tension which produces a desire to move about in an attempt to obtain relief. The restless legs syndrome, however, is characterized by feelings of discomfort in the lower limbs which force the subject to move in order to obtain some relief. There are a number of similarities between akathisia and restless legs syndrome. Both conditions produce a desire to move with an inability to sit or lie still and, in its extreme form, this results in restless pacing. It is likely that pathophysiological mechanisms involve the dopaminergic systems in both disorders, as shown by the fact that dopamine-receptor blocking drugs precipitate akathisia (Sigwald et al. 1947) and aggravate restless legs syndrome (Ekbom 1960, 1965, Akpinar 1982). In addition, Parkinson's disease is frequently associated with akathisia (Lang and Johnson 1987) and has been reported in association with restless legs syndrome (Lang 1987). There is also similarity between the drugs that produce relief of akathisia and restless legs syndrome, including benzodiazepines and opiates. While dopamine-receptor stimulants are effective in restless legs syndrome, their potential in neuroleptic-induced akathisia is widely unexplored because of their tendency to aggravate psychotic disorders (see under ‘Pathophyisological mechanisms’ in Chapter 46), but it may well be that they would similarly reduce drug-induced forms of akathisia. Both akathisia and restless legs syndrome may be associated with truly involuntary leg movements, many of which are myoclonic. In addition, such phenomena as body rocking and walking on the spot, which used to be thought characteristic of akathisia, have also been shown to occur in severe restless legs syndrome (Walters et al. 1988). The striking differences between akathisia and restless legs syndrome are the feelings of inattention and restlessness, which are characteristic of the former and the marked diurnal variation of the latter. Restless legs syndrome is thus almost exclusively symptomatic in the evening and night, or aggravated at these times. In addition, restless legs syndrome is highly associated with periodic movements of sleep which have not, so far, been demonstrated in akathisia.

The association between the syndrome of painful legs and moving toes and restlessness is less definite, and it could possibly have been included in Section 9 with Disorders of Continuous Muscle Fibre Activity. Although it is not truly a disorder of restlessness, it has a number of points of similarity with restless legs syndrome, with which it may be confused (Spillane et al. 1971, Montagna et al. 1983). Thus, both disorders present with pain and discomfort in the legs, associated with movements. Both conditions may impair sleep (Montagna et al. 1983). Symptoms in painful legs and moving toes syndrome, however, do not show diurnal variation and, far from movement relieving the discomfort, the pain often seems to be worse when the involuntary movements are particularly troublesome. Although both disorders can be associated with involuntary leg movements during sleep, the nature of these is different (Montagna et al. 1983). This section thus covers akathisia, restless legs syndrome (with periodic movements of sleep), and the syndrome of painful legs and moving toes.