Increased sensitivity to stress and episode recurrence in spontaneous recurrence of methamphetamine psychosis

Increased sensitivity to stress associated with noradrenergic hyperactivity and dopaminergic changes may precipitate stress-related psychiatric disord ers. The present study examines the relation between this increased sensiti vity and vulnerability to subsequent spontaneous recurrences of methampheta mine (MAP) psychosis (i.e. flashbacks). Plasma monoamine metabolite levels were assayed in 18 subjects with flashbacks, of whom ten experienced a sing le flashback and eight experienced further subsequent flashbacks; in 21 sub jects with a history of MAP psychosis who did not experience flashbacks; an d 33 controls. A square-root transformation was applied to monoaminergic va lues, rendering the distribution normal. The subjects with flashbacks had u ndergone frightening stressful experiences during previous MAP use. The dom inant factor triggering flashbacks was a mild fear of other people. During flashbacks, plasma noradrenaline levels markedly increased and 3-methoxytyr amine levels, an indicator of dopamine release, were elevated. Among the 18 subjects with flashbacks, the ten with subsequent flashbacks had markedly increased noradrenaline levels during flashbacks, whereas the eight with a single flashback displayed small increases in noradrenaline levels as well as 3-methoxytyramine levels. Thus, a mild fear of other people may have eli cited memories of MAP psychosis, related to frightening stressful experienc es through increased sensitivity to stress associated with noradrenergic hy peractivity, involving increased dopamine release. Robust noradrenergic hyp erreactivity to mild stress may predispose subjects to subsequent flashback s.