Characterizing Anticholinergic Abuse in Community Mental Health

Abstract

To identify factors associated with anticholinergic abuse in patients taking antipsychotics and anticholinergics and to document the extent of extrapyramidal side effects in anticholinergic abusers, 21 anticholinergic abusers were matched with 21 controls without a history of anticholinergic abuse for diagnosis and antipsychotic dose. Data were collected prospectively, and extrapyramidal side effects and abnormal involuntary movements were evaluated using the Modified Simpson Angus Scale and the Abnormal Involuntary Movement Scale. The abuse group reported significantly more subjective effects from anticholinergic agents than did those in the control group (mean +/- SD = 10.5 +/- 5.4 vs. 6.5 +/- 3.7, p less than 0.05). The abuse group was significantly more likely to report feeling a buzz (p less than 0.05) and difficulty learning (p less than 0.05) when taking anticholinergic medications. Abusers reported abusing significantly more drugs in the past (2.7 +/- 2.1 vs. 0.8 +/- 0.9, p less than 0.01) and had taken antipsychotics (12.7 +/- 6.3 vs. 8.7 +/- 5.4 years, p less than 0.05) and anticholinergics (10.9 +/- 3.1 vs. 6.1 +/- 4.6 years, p less than 0.01) significantly longer than controls had. Patients in the control group spent significantly more years working full-time than did abusers (6.2 +/- 7.3 vs. 0.7 +/- 1.4, p less than 0.01). There was a nonsignificant trend for abusers with a longer duration of antipsychotic use to have higher Abnormal Involuntary Movement Scale scores (r = 0.40, p less than 0.10). Although these drugs are potentially abusable, the term "anticholinergic abuse" should be reevaluated in light of accumulating evidence that many patients taking these drugs report improved functioning, with improvement in negative symptoms and minimal or no adverse anticholinergic effects.