[Negative results related to drugs required in hospitalisation]

To assess the prevalence of negative clinical outcomes associated with medication as a cause of hospital admission and to determine their characteristics (types, categories, avoidability, severity and the drug groups involved.) To determine possible risk factors related to the appearance of this problem.

An observational study carried out over a three month period in a department of the university hospital, 163 patients were selected at random. The information obtained from the patient interview, the revision of clinical records and clinical sessions were used to then identify negative clinical outcomes using the Dader method.

In 27 cases (16.6 %; 95 % confidence interval [CI], 1.6 to 23.0), negative clinical outcomes associated with medication were considered to be the main cause of hospital admission. The most frequent negative clinical outcomes associated with medication were untreated health problems, non-quantitative ineffectiveness and quantitative safety problems respectively. The overall prevalence of preventable admissions due to negative clinical outcomes associated with medication was 88.9 %; (95 % CI, 71.9 to 96.1 %.) With regards to severity, 74.1 % (95 % CI, 55.3 to 86.1 %) of the total admissions were moderate. The most common drugs implicated in hospital admissions were: antibacterial for systemic use, cardiovascular and non steroidal anti-inflammatory agents. Apart from age, no other factors were found for hospital admissions due to negative results associated with medication.

Negative clinical outcomes associated with medication as cause of hospital admission are a prevalent problem and most of them are avoidable with pharmacotherapeutic follow-up.