Non-adherence to Immunosuppressives in Kidney Transplantation in Brazil: Diagnosis and Associations - ADHERE BRAZIL Multicenter Study

Kidney transplant (KTx) is considered the best therapeutic option for patients with chronic kidney disease (CKD), based not only on medical reasons, but also on socioeconomic ones1. One of most important determinants of kidney transplants survival is the adherence to immunosuppressive drugs. Adherence may be defined as a patient's behavior agreement regarding the prescribed treatment, including the extent to which a person takes medications, follows a diet and/or implements lifestyle changes as prescribed by health care providers. In the setting of transplantation, a recent consensus conference stated nonadherence (NAd) as "deviation from the prescribed medication regimen sufficient to adversely influence the regimen's intended effect". Risk factors for NAd, have been categorized by the WHO into five dimensions: socioeconomic factors, disease, treatment factors, patient condition and health care team and health system characteristics. 2 Looking at all vascularized transplant recipients, KTx patients are reported like the most non-adherent.3 In Brazil, which is currently the second country in the absolute number of TxR, there are only two studies about prevalence of NAd, lacking in representativeness of the Brazilian scenario4,5. In 2012, 5.385 TxR were performed, but have clear regional differences in that activity: localized mostly in the South and Southeast regions, and performed by big services with high transplant activity transplantation. In this context, the approach of NAd can be fundamental importance in view of their influence on the results.6 The scientific literature recommends to use more than one a method for assessing adherence of the therapeutic regimen. Each method has advantages and disadvantages, and no method is actually considered the gold standard. On the other hand, a combination of measures maximizes accuracy to diagnostic of NAd.7,8 We intent to identify the prevalence of NAd to immunosuppressives in Brazilian kidney transplant patients, by using the more appropriated methodology of triangulation. As secondary objectives we will design the differences between centers and regions of the country as well the risk factors to NAd.

SAMPLE, SETTING AND DATA COLLECTION

Sample, Setting: The sample size was defined based on data from the 2012 Brazilian Registry of Transplant (2012 RBT)6 available by the Brazilian Association of Transplantation (ABTO). The total number of patients transplanted in Brazil from 2000 to 2012 was 59,001 , and 20,504 patients have been registered to be monitored in transplant centers who contribute to that register. Using the OpenEpi stats program, the sample was calculated for studies of population frequency, considering the hypothetical 50% confidence interval of 5% and design effect ranging from 2.0 to 3.0. The obtained sample size ranged from 755 to 1130 patients.

Selection of the centers participating in the study: According to 2012 RTB, there are 123 active transplant center in Brazil, distributed by 22 states, which performed 5.385 KTxs in that year. We will arbitrarily divide the centers in two regions, according to their transplantation activity: Region 1 or high activity, including centers from South and Southeast region, and Region 2 or low / moderate activity accomplishing centers from North, Northeast and Midwest. To ensure representativeness of the characteristics of the centers we will also take in account other characteristics: transplantation activity, university or not, presence of multidisciplinary team. We arbitrarily made a pre-selection of the centers, considering the above questions, to invite to participate of the study. The number of patients per center will be set in relation to the number of patients being followed. Patients will be randomly selected in a regular office visit using routine computerized method previously defined.

Data Collection: Data will be collected in 6-12 months and directly register in the Research Electronic Data Capture (RedCap) system during a regular office visit to transplant service, by a trained professional. The RedCap is a safe internet program, created by the Vanderbilt University, designed exclusively for capture and storage of data that can be powered remotely by trained people. The Federal University of Juiz de Fora is part of the consortium of institutions authorized to use this program. It allows data to be collected, organized and stored in the same action, making the process of data analysis (http://www.project-redcap.org/).