https://orcid.org/0000-0002-0774-5553
Abstract
Purpose
Tolvaptan is the only approved drug for the treatment of autosomal dominant polycystic kidney disease (ADPKD) and causes significant polyuria with secondary polydipsia. Up to now, there is no study that examines tolvaptan adherence and satisfaction with information received about tolvaptan in ADPKD patients 10 years after starting tolvaptan therapy.
Patients and Methods
This pilot study includes 12 ADPKD patients that were formerly enrolled in the tolvaptan registration trials and have continued to use tolvaptan thereafter. Data were collected once via questionnaires on patients’ self-reported adherence (MARS-D: Medication Adherence Report Scale - German version) and satisfaction with the information received about tolvaptan (SIMS-D: Satisfaction with Information about Medicines Scale - German version) at the time of the present study. In addition, serum creatinine levels and clinical data were evaluated.
Results
The MARS-D demonstrated strong adherence to tolvaptan (range of possible score: 5–25; median: 23.5; range of individual results: 5). The SIMS-D showed a high level of satisfaction with the information received about the action and usage of tolvaptan (SIMS-D AU subscale; range of possible score: 0–9; median: 9, range of individual results: 1), but also revealed dissatisfaction regarding the information received about potential problems of tolvaptan in 42% of the participants (SIMS-D PP subscale; range of possible score: 0–8; median: 8, range of individual results: 6). During treatment with tolvaptan, the eGFR decreased from 78.8 ± 15.9 mL/min/1.73 m2 to 48.3 ± 19.4 mL/min/1.73 m2 (P < 0.0001).
Conclusion
Although patients reported strong adherence to tolvaptan, there was still dissatisfaction with the information received about potential problems with tolvaptan. Therefore, our data suggest conduction of at least one patient survey on adherence and satisfaction with the information received about tolvaptan during any tolvaptan treatment to improve patient education regarding the use of tolvaptan in slowing down of ADPKD.
Abbreviations
AU, action and usage of medication subscale of SIMS-D; ADPKD, autosomal dominant polycystic kidney disease; cAMP, cyclic adenosine monophosphate; CKD, chronic kidney disease; CKD-EPI, chronic kidney disease epidemiology collaboration; eGFR, estimated glomerular filtration rate; HtTKV, height-adjusted total kidney volume; MARS-D, Medication Adherence Report Scale - German version; PKD1, polycystic kidney disease 1; PKD2, polycystic kidney disease 2; PP, potential problems of medication subscale of SIMS-D; SIMS-D, satisfaction with Information about Medicines Scale - German version; TEMPO, Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes trial; TSQM-9, Abbreviated Treatment Satisfaction Questionnaire for Medication.
Data Sharing Statement
The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request and with permission of Otsuka Pharmaceutical.
Ethics Approval and Informed Consent
The study protocol was approved by the University of Dresden Ethics Committee (Bearbeitungsnummer/Processing number: EK 237062017). The investigation conforms to the principles outlined in the Declaration of Helsinki. The patients were of legal age and able to consent. Enrollment into the study took place after detailed information and written informed consent.
Consent for Publication
All authors listed have consented to the publication.
Acknowledgments
The authors thank all participants of the study for their valuable time and selfless commitment. We would also like to thank Professor Rob Horne (© Rob Horne, School of Pharmacy, University College London, Great Britain) and the Department of General Practice and Health Services Research and Department of Internal Medicine IV, Clinical Pharmacology and Pharmacoepidemiology, University Hospital Heidelberg, Heidelberg, Germany, for providing the MARS-D and SIMS-D.
Author Contributions
All authors contributed to data analysis, drafting or revising the article, gave final approval of the version to be published, agreed to the submitted journal, and agree to be accountable for all aspects of the work.
Disclosure
C.H. reports grants from Otsuka, during the conduct of the study; grants and/or personal fees from Astellas, Sanofi, Genzyme, Roche Pharma, Novartis, and Wyeth/Pfizer, outside the submitted work; P.G. functioned as an investigator in REPRISE until November 2018 (REPRISE ClinicalTrials.gov number, NCT02160145; funded by Otsuka Pharmaceuticals and Otsuka Pharmaceutical Development and Commercialization); H.S. and A.P. declare that they have no competing interests.