[Longitudinality in Primary Care and Polypharmacy. A Systematic Review]

The aim of this work was to collect, evaluate and interpret the available evidence on the relationship between continuity in primary care (i.e., longitudinality), and the prevalence of polypharmacy and its associated problems. Following the PRISMA reporting statement, we carried out a systematic review of the literature searching PubMed and Scopus databases. The screening of titles and summaries and the review of references carried out independently by two authors detected 16 works of potential interest, of which 4 were discarded after the independent review of all the originals because they did not meet inclusion criteria. The 12 papers selected studied the relationship between Longitudinality, measured with various quantitative indices, and the rate of polypharmacy or various associated problems, such as duplicate drugs, inadequate prescriptions or drug interactions. They all showed a significant relationship, often strong (RR>2 or<0.5), between longitudinality indicators and the various dependent variables. Although our knowledge could be improved by prospective studies that more directly evaluate longitudinality and its impact on problems due to excess medication, with the existing evidence, we can affirm that the protection and promotion of continuity in primary care can be a key element for the control of polypharmacy and associated problems.