Among kidney transplant recipients, gender differences in medication adherence may contribute to higher graft failure risks observed in girls and young women compared with boys and young men. Our aim was to determine whether adherence differs by gender, and whether gender differences vary by age in adolescent and young adult kidney transplant recipients.
We examined data from the 3-month run-in period (no intervention) of the randomized Teen Adherence in Kidney transplant Effectiveness of Intervention trial. Adherence was monitored using electronic pillboxes in 136 patients (11–24 y) followed in 8 transplant centers in Canada and the United States. We used ordinal logistic regression with generalized estimating equations to estimate the association between gender and each of daily taking (proportion of prescribed doses taken) and timing (proportion of prescribed doses taken on time) adherence, considering effect modification by age (11–16 y vs 17–24 y).
No difference in taking adherence was observed by gender among participants aged 11 to 16 years (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.55–1.54), whereas among participants aged 17 to 24 years, women had significantly greater odds of higher taking adherence scores (OR, 3.03; 95% CI, 1.20–7.66) than men. Results were similar for timing adherence, with no difference among participants aged 11 to 16 years (OR, 1.03; 95% CI, 0.65–1.63) but a greater odds of higher timing adherence scores in women than in men among participants aged 17 to 24 years (OR, 3.26; 95% CI, 1.43–7.45). There were no differences in adherence assessed by self-report or SD of tacrolimus trough levels.
Gender differences in adherence vary by age. Whereas younger adolescents show no adherence differences by gender, young women show much better adherence than young men.
1 Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada.
2 Center for Adherence and Self-Management, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH.
3 Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH.
4 Division of Pediatric Nephrology, Hypertension and Pheresis, Washington University School of Medicine, St. Louis, MO.
5 St. Louis Children’s Hospital, St. Louis, MO.
6 Department of Pediatrics, The Hospital for Sick Children, Toronto, ON, Canada.
7 Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA.
8 Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA.
9 Research Institute of the McGill University Health Centre, Montreal, QC, Canada.
10 Department of Pediatrics, McGill University, Montreal, QC, Canada.
11 Division of Nephrology, Department of Pediatrics, Montreal Children’s Hospital, Montreal, QC, Canada.
Received 4 April 2018. Revision received 15 June 2018.
Accepted 1 July 2018.
TAKE-IT registration number: Clinicaltrials.gov registration: NCT01356277 (May 17, 2011).
The authors declare no conflicts of interest to disclose, except Dr. Foster, who is a co-investigator on 2 investigator-initiated studies funded by Astellas Canada.
The study was funded by the American National Institutes of Health, National Institutes of Diabetes, Digestive and Kidney diseases (NIDDK; R01DK092977). The funder had no role in study design, data collection, analysis, interpretation of data, writing the report, or and the decision to submit the report for publication. J.B., who was a postdoctoral fellow at the Research Institute of the McGill University Health Centre when this study was done, was supported by an RI MUHC—Desjardins Studentship in Child Health Research. B.J.F., a member of the Research Institute of the McGill University Health Centre, was supported by a Fonds de recherche du Quebec Santé Chercheur-Boursier Clinicien award.
All authors participated in research design, in the writing of the article, and in data analysis.
Supplemental digital content (SDC) is available for this article. Direct URL citations appear in the printed text, and links to the digital files are provided in the HTML text of this article on the journal’s Web site (www.transplantjournal.com).
Correspondence: Bethany J. Foster, 1001 Decarie Blvd Montreal, QC, Canada H4A 3J1. (firstname.lastname@example.org).