Adjustments of medication dosages in patients with renal impairment in Botswana; findings and implications to improve patient care

Background and aims: Medication dosage adjustments for renally impaired patients have not been studied in Botswana. This study was conducted to determine prescribing practices among patients with renal impairment in medical wards to improve future patient care.Methods: We conducted a retrospective study involving medical charts of patients admitted at a tertiary level hospital in Gaborone Botswana. Study participants included all patients admitted between August and October 2016 who were hospitalized for ≥24 h. ‘Drug prescribing in renal failure: dosing guidelines for adults and children'. was used to determine the extent of dosage adjustments. A logistic regression model was used to assess which patient factors were associated with inappropriate dosage adjustment.Results: Twenty-nine percent (233/804) of patients had renal impairment. Of these, 184 patients with renal impairment were included in the final analysis. There were 1143 prescription entries, of which 20.5% (n = 234) required dosage adjustment for renal function but only 45.7% (n = 107) were adjusted correctly. Of note, 112 patients were prescribed at least one drug that required dosage adjustment and only 30.4% (n = 34) patients had all of their medications appropriately adjusted. Patient factors associated with inappropriate dosage adjustment included a higher number of medicines being prescribed. Mortality among patients with renal impairment was independently associated with higher scores of the Charlson comorbidity index and hospital stay duration of 1–7 days.Conclusion: The renal function status of patients was not sufficiently taken into account when prescribing medicines especially in patients with severely impaired kidney function in Botswana. Continuous medical education needs to be encouraged to address this, which is being implemented. We will be following this up in future studies.