Association between stereotypic behavior and polydipsia in chronic schizophrenic patients.

We assessed temporal associations between polydipsia and motor stereotypies in chronic schizophrenia. Subjects included: (a) a polydipsic patient with marked stereotypies; (b) a polydipsic patient with no history of stereotypy; (c) a nonpolydipsic patient. Stereotyped grooming and pacing were significantly associated with drinking for polydipsic patients only (polydipsic patients evidenced a 87% and 66% concordance between excessive grooming and drinking versus 12% in the control). Our findings provide the first empirical demonstration that polydipsia is temporally associated with other repetitive behaviors. The use of behavioral assessment to examine etiological theories suggesting that polydipsia stems from interacting environmental, biological, and pharmacological variables is discussed.