Inappropriate consumption and over-prescription of antibiotics have been extensively reported. Our aim was to specifically evaluate the antibiotic prescribing patterns and appropriateness among the elderly (≥65 years) from the Lombardy region (Italy) in primary care. Antibiotic consumption (as DID: DDD/1000 inhabitants × day) and prevalence rates in 2018 were assessed, and the prescribing quality was evaluated using ESAC-based indicators and WHO-AWaRe criteria. A multivariate logistic regression analysis was performed to evaluate the association between the probability of receiving an antibiotic prescription and patients' and physicians' characteristics. A total of 237,004 antibiotic users were included (mean age ± SD 75.98 ± 7.63; males 42.7%). Antibacterial consumption was equal to 17.2 DID, with values increasing with age in both males and females. The study found that the proportion of patients with at least one antibiotic prescription in 2018 was around 39.1%, with different age-related trends between males and females. Consumption (as DID) of cephalosporines (65-74 years: 1.65; 75-84 years: 2.06; ≥85 years: 2.86) and quinolones (3.88, 4.61, 4.96, respectively) increased with growing age, while consumption of penicillins (6.21, 6.08, 6.04, respectively) and macrolides, lincosamides, and streptogramins (3.25, 2.91, 2.64, respectively) decreased. In 2018, antibiotics considered to have higher toxicity concerns or resistance potential, as reported by WHO-AWaRe tool, were consumed more intensively than those to be used as first choices, independent of age and sex. The probability of receiving an antibiotic prescription was greater in females, in subjects with polypharmacy, in treatment with respiratory drugs, anti-inflammatory agents or glucocorticoids, and with previous hospitalization; but increasing age was less associated with exposition to antibiotics.
Keywords: anti-bacterial agents; antibiotic consumption; elderly; inappropriate prescribing.