Relationship between polypharmacy and frequency of adverse events to antiparkinsonian drugs: a preliminary study.

VERÓNICA REY; SANTIAGO PEREZ-LLORET; JEAN-LOUIS MONTASTRUC; OLIVIER RASCOL

Toronto, Canada

Congreso; Congreso Internacional de Movimientos Anormales; 2011

Objective: To evaluate the relationship between polypharmacy and most frequent AEs to antiparkinsoniandrugs (APDs) reported by Parkinson disease patients.Background: Polypharmacy is frequent in the elderly and is known to enhance the risk of related to adverseevents (AEs).Methods: 203 non-demented, non-operated Parkinson´s disease out-patients were recruited at the Toulouseand Bordeaux Movement Disorder Clinic (mean age 67 years, 62% males, and mean disease duration 9 years,mean UPDRS II+III in ON-state 37). They were systematically questioned about the presence of a predefinedlist of the most common AEs to APDs. Polypharmacy was arbitrarily defined as consumption of > 5medicaments (i.e. the median in the sample). Medications were coded by ATC.Results: Most frequent explored AEs were: weight loss, fatigue, leg oedemas, dry mouth, nausea/vomiting(NV), memory complaints, somnolence, impulse-control disorders (ICDs), orthostatic hypotension (OH), andpsychotic events (PE). Polypharmacy was present in 68 patients (34%) and was related by multivariatedlogistic regression to weight loss (OR [95% CI]: 2.44 [1.07-5.56]), dry mouth (2.33 [1.25-4.37]), NV (2.72[1.32-5.62]) and somnolence (1.87 [1.03-3.42]). On the other hand fatigue, oedemas, memory complaints,ICDs, OH and PE were not related to polypharmacy. Some medications were related to each of these AEs.Weight loss was independently related to H+-pump inhibitors (2.71 [1.00-7.45]) or domperidone (2.68[1.12-6.41]); oedemas to dopamine agonists (2.42 [1.08-5.41]); dry mouth to amantadine(4.03[1.74-11.12]), opioids (OR could not be calculated) or antidepressants (3.16 [1.47-6.79]); memorycomplaints to statins (2.85 [1.09-7.45]); ICDs to dopamine agonists (OR could not be calculated) and MAO-Binhibitors (3.76 [1.12-12.67]); OH to lack of MAO-B inhibitors (0.08 [0.01-0.68]) and non-benzodiacepinichypnotics (3.64 [1.46-9.04]); and PE to amantadine (3.03 [1.18-7.77]). Fatigue, NV and somnolence were notrelated to any particular drug.Conclusions: Polypharmacy was related to the occurrence of some AEs to APDs in this preliminary studyincluding: weight loss, dry mouth, NV and somnolence. Moreover, the presence of several AEs was also relatedwith particular drugs (leg oedemas, memory complaints, ICDs, OH and PE).