Long-term use of pharmacological treatment in Alzheimer’s disease: a retrospective cohort study in real-world clinical practice

Purpose To assess the impact of long-term use of different drugs commonly prescribed in Alzheimer’s disease (AD) on its clinical course and to identify clinical and therapeutic factors associated with a delay in AD progression. Methods We retrospectively enrolled 50 patients visited at the Neurology Unit, Careggi University Hospital (Florence), followed for at least 24 months. AD diagnosis was made according to clinical diagnostic criteria for probable/possible AD dementia, always supported at least by one biomarker. Clinical features, MMSE scores evaluated at diagnosis and every 6 months, and AD drugs used for at least 6 months, were recorded. Cox regression analysis was performed to estimate the hazard ratio (HR) for AD progression, assuming as the “final event,” the progression to a more severe disease stage, defined as the achievement of an MMSE score less than 10. Results At baseline, the median MMSE score was 22. During follow-up (median of 41 months), 56% of patients progressed to a more severe disease stage. The use of memantine, either alone (HR 0.24; 95% CI 0.09–0.60) or combined with acetylcholinesterase inhibitors (HR 0.35; 95% CI 0.14–0.88) and a higher MMSE score at baseline (HR 0.82; 95% CI 0.70–0.96) were associated with a significantly lower risk of AD progression. Conclusion Nowadays, effective disease-modifying therapy for AD is missing. Nevertheless, when the diagnosis is established, our results support the advantage of long-term use of available pharmacological treatments, especially in combination, in delaying AD progression to its more severe disease stage.