Drug prescriptions unadapted to the renal function in patients aged 80 years and older

Abstract

Background: Drug-related problems are common in older people. Often they are related to low estimated glomerular filtration rate (eGFR), which has a high prevalence among older adults.

Objectives: The aim of this study was to investigate inappropriate drug prescriptions and dose adaptations in a very old population and their relationship with the eGFR.

Methods: Design: A cross-sectional study within a Belgian prospective population-based cohort study (the BELFRAIL study) of 539 participants aged 80 years and older (mean age 85 years). Drug prescriptions at inclusion were reported by the participant's responsible general practitioner. The eGFR was estimated using the MDRD equation. Based on their eGFR, the participants were divided in three groups: > 50, 30–50 and < 30 ml/min/1.73 m², respectively. Drug prescriptions were analysed in different eGFR groups. The prevalence and odds ratios of inappropriate drugs and the unadjusted defined daily doses (DDD) of the participant eGFRs were calculated.

Results: Thirty-six (of 111) and eight (of 31) of the participants with an eGFR between 30–50 and < 30 ml/min/1.73 m², respectively, had at least one inappropriate drug prescribed. No decrease in mean DDD, was observed in any prescribed drug in both lower eGFR groups. Participants with a lower eGFR were at higher risk of receiving gliclazide (OR: 4.51; 95% CI: 1.45–14.02) or unadjusted doses of allopurinol (OR: 3.48; 95% CI: 1.26–9.61).

Conclusion: Drug prescriptions inappropriate for patient eGFR are common in subjects aged 80 years and older, despite automatic eGFR reporting.

Keywords::

• Drug use
• elderly
• renal function
• eGFR
• inappropriate prescriptions

Acknowledgments

GVP is a fellow of the Research Foundation-Flanders (FWO).

This study was only possible thanks to the participating GPs who included their patients. The authors should like to thank Dr Etienne Baijot (Beauraing), Dr Pierre Leclercq (Pondrôme), Dr Baudouin Demblon (Wellin), D Daniel Simon (Rochefort), Dr Daniel Vanthuyne (Celles), Dr Yvan Mouton (Godinne), Dr Louis-Philippe Docquier (Maffe), Dr Tanguy Dethier (Ciney), Dr Patricia Eeckeleers (Leignon), Dr Jean-Paul Decaux (Dinant), Dr Christian Fery (Dinant), Dr Pascale Pierret (Heure), Dr Paul-Emile Blondeau (Beauraing), Dr Baudry Gubin (Beauraing), Dr Jacques Guisset (Wellin), Dr Quentin Gillet (Mohiville), Dr Arlette Germay (Houyet), Dr Jan Craenen (Hoeilaart), Dr Luc Meeus (Hoeilaart), Dr Herman Docx (Hoeilaart), Dr Ann Van Damme (Hoeilaart), Dr Sofie Dedeurwaerdere (Hoeilaart), Dr Bert Vaes (Hoeilaart), Dr Stein Bergiers (Hoeilaart), Dr Bernard Deman (Hoeilaart), Dr Edmond Charlier (Overijse), Dr Serge Tollet (Overijse), Dr Eddy Van Keerberghen (Overijse), Dr Etienne Smets (Overijse), Dr Yves Van Exem (Overijse), Dr Lutgart Deridder (Overijse), Dr Jan Degryse (Oudergem), Dr Katrien Van Roy (Oudergem), Dr Veerle Goossens (Tervuren), Dr Herman Willems (Overijse) and Dr Marleen Moriau (Bosvoorde).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

The BELFRAIL study (B40320084685) is funded by an unconditional grant from the Fondation Louvain. The Fondation Louvain is the support unit of the Université Catholique de Louvain in charge of developing education and research projects of the university by collecting gifts from corporate, foundations and alumni.