Prescribing quality indicators

The pharmacological treatment of elderly patients who are affected by chronic pathologies is doubtlessly a relevant issue.1 Data provided by the OsMed Report confirm that age is the most influential factor for drug use in the population, with average per capita expenditure 11 times higher for 65 years old patients than for people aged 25-34.
Polypathology, lack of periodical revision of the therapy, excess of self-medication and intake errors, all contribute to several drugs use and increase the risk of possible drug interactions and adverse reactions.2 The appropriate use of drugs is therefore one of the biggest challenge for clinical geriatric. Sine 1991, several study groups tried to develop instruments for identifying potentially inappropriate drugs;3 among these, Beers criteria in the United States and STOPP/START criteria in Ireland and United Kingdom.4,5 In Italy, the Geriatric Working Group of the Italian Agency of Medicines has developed a set of useful indicators for evaluating the quality of drug prescriptions for over-65 patients.6 Initially, various classes of prescribing inappropriateness have been identified through a wide revision of scientific literature; within each class, then, several indicators have been highlighted, selecting only those relative to drugs that are reimbursed by the National Healthcare System – whose prevalence have been evaluated by analysing the OsMed database, which collects data on A-category drugs dispensed on the national territory (more than 500 million prescriptions per year). The work group has defined 13 indicators, based on clinical-epidemiological relevance and data availability on their effects (table1). Informative sheets have been produced for each indicator, reviewed by national experts of pharmacoepidemiology. Polypharmacotherapy, adherence to therapy, prescribing cascade, undertreatment, drug interaction and drugs to avoid are the 6 categories that contain them.

Polypharmacotherapy has become a very common phenomena, in fact 11% of the elderly population (about 1.4 million people over the national territory) receive at the same time 10 or more drugs. Among the relevant prescribing factors, low adherence to therapy emerges: low adherence to therapy of antidepressants, antihypertensive, anti-diabetic and anti-osteoporosis drugs has been observed between 46 and 64%. The phenomena of prescribing cascade (i.e. when a drug adverse reaction is not recognized and is interpreted as symptom of an emerging disease, causing new drug prescriptions) is less common, with about 0.2% of the population that use antipsychotics and anti-Parkinson drugs. On the other side, pharmacological interactions are quite relevant. The simultaneous use of drugs that increase the risk of renal failure (ACE inhibitors, spironolactone and NSAIDs) has been reported in 0.7% of the population, the use of drugs that increase haemorrhagic risk (NSAIDs, antiplatelets and anticoagulant drugs) in 0.2% and the use of two or more drugs with proved QT prolongation effect in 0.3%. Very important also the use of drugs “to be avoided” such as some antihypertensives (1.65 of general population; 2.5% of hypertensive population), glibenclamide and chlorpropamide (0.7% of general population; 5.1% of diabetic population), digitalis at high dosage (0.4% of population). Undertreatment, i.e. the non-use of drugs for which clear beneficial effects for the treatment of a pathology have been identified – also resulted quite common (non-use of statins in diabetic patients, reported in 53.4% of cases).
In conclusion, these data are important not only for the identification of prescribing quality indicators, but also because these indicators are applied for the first time to the whole Italian elderly population. The results of this analysis clearly suggest the need of constant overall and integrated revision of the patient in order to always guarantee prescribing appropriateness.