Therapeutic non-adherence isa clinical challenge that likelyhas vexed doctors for centuries,perhaps millennia. If patientsfail to take their medications or keepappointments to receive maintenancetherapies, the conditions for whichthey are prescribed treatment cannotbe controlled, potentially leading toincreased morbidity and mortality.As with other medical specialties,nephrology and urology have theirshare of non-adherent patients, as illustrated by 2 studies presented atthe American Urological Association (AUA) annual meeting and whichwe report on.
In a study of patients with non-muscle invasive bladder cancer, Alexander M. Helfand, BA, a fourth-year medical student, andcolleagues found poor adherence to maintenance therapy, with “realworld”rates of adherence lower than those observed in most clinicaltrials. Only 10% of patients on the Lamm schedule completed 3 years oftreatment with 21 maintenance instillations, Helfand’s group reported.In the other study, Yooni Yi, MD, and colleagues found thatonly 50% of patients with kidney stones adhered to their prescribedmedical therapy. Being placed on combination therapy and femalegender were independently associated with lower odds of adherence.
These findings resonate with some of the published literature on nonadherence.Last year, in the Journal of Nephrology (2014;27:673-679),investigators published the results of an 8-week study of 135 hemodialysis (HD) patients showing that each week, about half of patients were adherent(missing less than 1 total daily dose per week) to phosphate bindertreatment. Over the 8-week period, only 22% of patients were totallyadherent (missing less than 1 total daily dose per week, every week). Livingwith a partner, greater social support, and better physical quality of lifewere associated with being totally adherence, the investigators reported.
Pill burden has emerged as a possible reason for non-adherence tophosphate binder therapy. A study of 233 dialysis patients found that themedian daily pill burden was 19, with phosphate binders accounting forabout half of this, according to a study published in the Clinical Journalof the American Society of Nephrology (2009;4:1089-1096). “The dailypill burden in dialysis patients is one of the highest reported to date inany chronic disease state,” the authors concluded. Results showed that62% of subjects were non-adherent. A study of 8,616 HD patients foundthat a higher pill burden was associated with lower adherence, and loweradherence was associated with higher mean phosphorus levels, researchersreported in Nephrology Dialysis Transplantation (2014;29:2092-2099).
The aforementioned new studies presented at the AUA meetingshould serve as reminders that no matter how much pharmacologictherapy advances, patient behavior will remain a significant factor inthe outcomes achieved.