[Drug prescription profile in patients with advanced chronic diseases]

To analyze the prescription profile and the factors associated with multiple medications (polypharmacy) and non-adherence in patients with advanced chronic diseases.

Longitudinal cross-sectional study including 41 Spanish hospitals (PALIAR project). Polypharmacy was defined as a prescribed treatment with five or more drugs, and excessive polypharmacy when the number was ten or more. The adherence was evaluated using a questionnaire completed by the patients or their caregivers. Description of drug prescription profile and analysis was performed on the risk factors associated with multiple medications and non-adherence.

The study included 1847 patients, and 1778 (96.2%) completed the questionnaire. Mean age was 78.74±10 years. Antihypertensives (82.6%), gastroprotectives (73.8%), anti-platelets/anticoagulants (70.3%), and psychotropic drugs (51.8%) were the most frequently prescribed drugs. Prevalence of polypharmacy/excessive polypharmacy was 86.2%/31.3%, with a mean of 8±3.5 drugs per patient. Errors in treatment compliance were detected in 48.2% of patients, but 38.5% and 9.6% referred to an occasional or almost daily failure, respectively. Factors associated with non-adherence were: to be a patient with multiple diseases, cognitive impairment, three or more 3 hospital admissions in the last three months, and having polypharmacy. Factors associated with polypharmacy were: to be a patient with multiple diseases, an ECOG score <3, age <85 years, and 3 or more hospital admissions. Factors associated with excessive polypharmacy were: to be a patient with multiple diseases and previous frequent hospital admissions.

The prevalence of polypharmacy in patients with advanced chronic diseases is high, and mistakes in treatment compliance are frequent. Further studies with better defined objectives and more specific therapeutic limits are needed.