Prescription inappropriateness in geriatrics: the STOPP&START criteria today

The management of the pharmacological therapy in the elderly patient has become more and more a relevant and critical aspect.¹ The physiological aging process is characterised by structural and functional changes that affect all systems and translate in a reduced ability to maintain homeostasis and an increased vulnerability to external attacks. In addition to the complex physiopathology of the elderly, chronic diseases and comorbidities, often present, frequently impose multiple prescriptions, enhancing the sensitiveness to drug interactions and adverse reactions.²
The definition of prescription inappropriateness includes: wrong prescriptions (drugs that increase significantly the risk of adverse events), unjustified prescription (drug prescribed without a clear clinical indication) and missed prescriptions (omission of drugs with a potential benefit).^3,4
In choosing the most appropriate therapy for the patient, it is essential to keep in mind factors like comorbidity, functional and cognitive state, therapeutic goals and life expectancy. Prescription inappropriateness is one of the principal risk factors for adverse reactions in the elderly, which cause hospitalisation, death and a wide use of financial and healthcare resources.^5,6,7
If we consider that the major part of adverse reactions to drugs could be prevented,⁸ an instrument able to detect prescription inappropriateness would be essential for improving the quality of healthcare.⁹

A method that works

The STOPP&START method is a screening tool for prescription inappropriateness based on two typologies of criteria: classes of drugs that should not be prescribed to elderly patients (STOPP: Screening Tool of Older Person’s Prescriptions) and classes of drugs that should be prescribed (START: Screening Tool to Alert doctors to Right Treatment). The first version of the STOPP&START criteria was validated and published in 2008 and had been elaborated by a group of English and Irish experts in geriatric pharmacology using the Delphi method.¹⁰ In literature there are both observational studies and clinical trials that have applied these criteria¹¹ and showed the greater sensitiveness and completeness of this method compared to others (e.g. the well-known US Beers criteria).¹² Applying the method as a screening tool when the patient is hospitalised is linked to an improved prescription appropriateness at the discharge and later on, reduced delirium episodes, falls and hospitalisation duration, besides savings in financial terms.¹³
In October 2014 an update of the STOPP&START criteria was published: the number of recommendations increased from 87 to 114 and their elaboration involved experts in geriatric pharmacology from 13 European countries.¹⁴
There are 80 STOPP criteria: they identify the drugs that must be discontinued in the elderly patient because of wrong posology, therapy duration or missing clinical indications. There are 34 START criteria: they identify the drugs with potential benefit or prevention of a disease.
To date, few studies have used the new STOPP&START criteria.

The first study in Italy

One of the first Italian observational studies with the updated version of the criteria has been conducted at the Geriatric Unit A and B of the University Hospital of Verona between September 2015 and February 2016. The patients included in the study were the first 5 patients hospitalised of each week, regardless of their age, provenience, gender or type of disease; those with less than 6 months of life expectancy were excluded. From the study emerges that the prevalence of prescription inappropriateness in elderly patients is elevated.
Among the most frequent inappropriateness according to the STOPP criteria: the inappropriate use of benzodiazepines, drugs prescribed without a specific duration, even when this was clearly defined, drugs prescribed without the support of a clinical indication (most frequently proton pump inhibitors and allopurinol), concomitant presence in the therapy of aldosterone antagonist and potassium-sparing diuretics without a biannual monitoring of potassium blood levels and, to conclude, the prescription of ticlopidine (even though there are more effective and safer alternative drugs).
In regard to the most missed prescriptions according to the START criteria, it has been observed that: 30% of the patients had not been covered by the anti-flu vaccine the previous year, none had ever been vaccinated against the pneumococcus and no discharge letter recommended the vaccinations. Other frequent omissions of prescriptions concerned vitamin D and calcium supplementation in patients at risk of deficiency and the missed prescription of antiplatelet, statins and ACE inhibitors therapies.
In regard to the impact of hospitalisation on the therapies, it has been observed that the average number of inappropriate drugs per patient according to STOPP criteria diminished (statistically significant decrease) at the discharge compared to the admission. The prevalence of patients with at least one inappropriate drug in the therapy passed from 77% at the admission to 66% at the discharge. In regard to the impact of hospitalisation on missed prescriptions (START) it has been observed that the prevalence of patients with at least one omission was 100% both at the admission and the discharge. It has also been noted, however, that by excluding the vaccinations from the analysis the trend of the prevalence between admission and discharge changed: the prevalence of patients with at least one missed prescription diminished at the discharge, passing from 59% at the admission to 51%.
In the same study the patients at higher risk of prescription inappropriateness, and therefore those who need to be evaluated most accurately, were: those who were institutionalised or received home assistance, those who were bedridden or had low-mobility, patients who had been hospitalized once or more in the last year, those with one or more geriatric syndromes, patients under polytherapy or with cognitive decline. Besides, it has been observed that the concomitant presence of four factors (cognitive decline, place of provenience, low mobility, at least one hospitalisation in the last year) was associated with an increased risk of inappropriate prescription. In particular, having 3 or 4 of these factors meant a 5-times increase in the risk of having two or more inappropriate drugs in the therapy (odds ratio: 5.5) compared to whom did not have these factors. Applying the STOPP&START criteria as a screening tool when admitting a patient to the hospital or to the general practitioner clinic could offer the opportunity to reflect upon the patient’s therapy and identify the prescription mistakes or omissions. This method cannot substitute the clinical evaluation and judgement, but could be an instrument to support and optimise the therapies, that for fragile patients like the elderly need to be re-evaluated frequently.