1. Background

The number of people diagnosed with end-stage renal disease (ESRD) is increasing as a result of the aging society in South Korea and a corresponding increase in chronic disease [1]. Kidney transplantation (KT) is known to be the best treatment option for people with ESRD; it can improve quality of life, alleviate suffering from uremic symptoms, and offer a chance to live longer when compared to dialysis [2-4]. For these reasons, ESRD patients are more likely to choose transplantation over dialysis, and the number of candidates for deceased donor kidney transplantation (DDKT) has steadily increased with 21,048 patients on the KT waiting list in 2018 [5].

However, the deceased organ donation rate in Korea is nine per million people annually, which is only one-quarter to one-fifth that in countries such as Spain (47 per million) and the United States (32 per million) [5]. Furthermore, since 2016, the annual number of organ donations in Korea has been decreasing due to several social issues. For example, negative media reports on donor families’ dissatisfaction with how they were treated after organ donation—such as receiving little or no support and respect from medical personnel during the funeral process—have created negative perceptions about organ donation among the public. In addition, the families of some end-stage patients who are potential organ donors decide to withdraw them from life-sustaining treatment, which deprives them of the chance to donate their organs [6]. From the hospital perspective, labor shortage, due to the enforcement of a statutory working hour limitation for healthcare workers, has created donor management issues [6]. Therefore, the discrepancy between the number of patients awaiting KT and the deceased donor kidney supply is rapidly growing larger. These and other factors create a serious problem for those awaiting transplants and compared with ESRD patients in many Western countries, Koreans are experiencing a longer waiting time for DDKT. In fact, according to the annual report of the Korean Network for Organ Sharing (KONOS) [5], the mean waiting time for DDKT increased from 1,732 days in 2012 to 1,955 days in 2017. Additionally, DDKT candidates are faced with longer waiting times than candidates for other organ transplants.

The prolonged waiting times result in physical and psychosocial issues for DDKT candidates. The literature shows that compared with the general population, candidates on the waiting list for DDKT have higher mortality rates, more complex medical conditions and more comorbidities, and a greater number of psychological problems such as severe anxiety, depression, and stress [7-9], all of which are associated with their long waiting times [9,10]. Moreover, these risk factors can negatively affect post-transplant outcomes. In particular, recent studies have reported that pre-transplant psychosocial factors can have a negative impact on post-transplant psychosocial status and on patient compliance with treatment regimens such as immunosuppressant medication [11], consequently adversely influencing transplantation outcomes, including mortality [12]. Therefore, a thorough pre-transplant psychosocial assessment of DDKT candidates is necessary during the waiting period to identify and address high psychosocial risk.

Current guidelines recommend a detailed evaluation of DDKT candidates, including their psychosocial characteristics [13]. Psychosocial assessment is an integral component of transplantation evaluation, especially because transplantation is a highly complex procedure that requires frequent pre- and post-transplant medical care and systematic management of the patient. Once listed as candidates, patients move into what may be the most stressful period of the entire transplantation process. Therefore, for an integrated and multi-dimensional psychosocial assessment, transplantation specialists and physicians should extend their evaluation beyond basic psychosocial health, to consider whether a candidate has strong social support, a suitable lifestyle for compliance with the treatment regimen, and a full understanding of the entire transplantation process [14]. However, little attention is given to the psychosocial status of DDKT candidates in Korea, who experience longer waiting times for transplantation than is the case in most Western countries.

Standardized screening tools and evaluation criteria are essential for successful DDKT candidate management in the clinical setting [14]. Although pre-transplant physical evaluation criteria are relatively well defined, pre-transplant psychosocial assessments are less standardized, and few evidence-based guidelines or universal criteria are available for them [13]. As a result, many different formal and informal psychosocial assessment methods are employed across transplantation centers. Furthermore, psychosocial assessments and systematic management of DDKT candidates by social workers or psychiatrists are not yet routinely performed at such centers, nor have they been integrated into the routine care of wait-listed patients [16]. The Psychosocial Assessment of Candidates for Transplantation (PACT) is a scale developed to assess factors influencing psychosocial outcomes in transplantation patients. It was originally created to support the clinical judgment of clinicians and has been used by transplantation team members to make decisions about patients’ candidacy [17]. The PACT is a validated instrument that assesses transplantation-specific psychosocial risk factors. It is a helpful and easy-to-use scale that any clinician completing a psychosocial assessment can use. Recent studies have employed standardized, transplantation- specific tools such as the PACT scale to assess whether pretransplant psychosocial risk predicted post-transplant mortality among liver and heart transplantation candidates [18,19].

Psychosocial status and risk factors have rarely been investigated among DDKT candidates. Although some studies have examined the pretransplant psychosocial status of transplantation candidates, only a few studies have addressed stress and coping [20], anxiety, or depression [21], examining single variables with a focus on psychopathology in such individuals, and those studies have not used a standardized, transplantation-specific tool to assess integrated psychosocial status and candidacy for kidney transplantation. Additionally, most of these studies focus on patients’ subjective experiences, conducted through self-report surveys. Therefore, these findings do not lead to prediction or management of vulnerable and high-risk patients in the clinical setting. Consequently, little reliable information is available about the psychosocial status of wait-listed candidates.

Therefore, the assessment of DDKT candidates’ psychosocial status using specific, standardized tools and the screening of their psychosocial vulnerability in the pretransplant period is of particular importance to allow transplantation teams to identify predictors of psychosocial risk.

2. Aims of the Study

The purpose of this study was to (1) assess the psychosocial status of DDKT candidates in Korea using the global PACT score, and (2) identify predictors of high psychosocial risk. The results of this study provide information on DDKT candidates’ psychosocial status that can guide transplantation teams in developing specific interventions for wait-listed candidates to enhance their psychosocial status and improve transplantation outcomes.

1. Study Design

A descriptive, cross-sectional design was used for this study.

2. Participants

The study used a convenience sample of 157 DDKT candidates enrolled at an organ transplantation center (OTC) in Korea. Under the inclusion criteria, the study participants had to be 19 years of age or older, able to respond to the questionnaire, registered as a candidate in KONOS, and who had visited the OTC at least once to receive the 30-minute routine education from the kidney transplantation coordinator about guiding and preparing for DDKT.

Using the G*Power 3.1.9 program for statistical power analysis, the sample size was calculated to be 139, at a significance level of .05, a power of .80, and an effect size of .15 for logistic regression. Considering the expected attrition rate of 30%, 180 individuals were screened. The final sample consisted of 157 participants after excluding 23 individuals who failed to meet the inclusion criteria.

3. Data Collection

Data were collected from March 1 to December 31, 2017, through face-to-face interviews with participants using structured questionnaires, and from participants’ medical records and KONOS data. At the OTC, after a routine medical follow-up, eligible patients were asked by a researcher whether they were willing to participate in this study. The transplantation counseling room at the OTC was set as the data collection location to maintain patient comfort and confidentiality. For each participant, one interview, for an average of 30 minutes, was conducted to complete the psychosocial assessment.

The psychosocial assessment was performed by a KONOS-registered transplantation coordinator with over 10 years of work experience related to kidney transplantation. Each assessment included completion of the PACT scale, and utilized the information obtained from a comprehensive interview as well as from the social worker and nephrologist discussions with the participant. All KONOS-registered coordinators and nephrologists receive continuous training from transplant institutions in order to develop specialized care and communication skills for the management of patients. The coordinators in particular, play a unique role because they have the closest and most frequent contact with the patient. Prior to the psychosocial assessments, the coordinator and nephrologist received guidance from one of the original authors of PACT on how the instrument scores should be recorded. Finally, they agreed on each participant’s final PACT score, and after consultation with the participant, the nephrologist registered her/him as a candidate on the KONOS waiting list.

4. Ethical Considerations

This study was approved by the Institutional Review Board (IRB) of C University Hospital (IRB No. CUH 2015-07-008-002). The study’s purpose and procedures were explained to the patients and those who volunteered to participate provided written informed consent.

5. Measurements

6. Data Analyses

Psychosocial status and the sociodemographic and clinical characteristics were analyzed using descriptive statistics. Means and standard deviations were examined for continuous data, and frequencies and percentages were examined for categorical data. Binary logistic regression was performed to identify the potential predictors of psychosocial risk, which was a dichotomous variable. To determine predictors of high psychosocial risk, univariate logistic regressions were performed. The statistically significant variables in the univariate logistic regression analyses—KTMI score, RCRI score, waiting time, previous kidney transplantation, BMI, location of dialysis, age, gender, occupation, marital status, and type of health insurance—were included as covariates in a multivariate logistic regression by the enter procedure; the statistical significance level was set at p <0.05. Statistical analyses were conducted using SPSS version 22.0 (IBM SPSS Statistics for Windows, Armonk, NY: IBM Corporation). For the PACT cutoff point test, the receiver operating characteristics (ROC) curve was used to analyze the test results in order to calculate the area under the curve (AUC) and a cutoff point for Korean DDKT candidates.

1. Participant Psychosocial Status

As shown in Table 1, the mean score of the PACT final rating was 2.10. Among the PACT subscales, participants’ social support was rated the highest (3.59), whereas understanding of the transplantation process and follow-up was rated the lowest (2.37).

Table 1.

Level of PACT Subscales and Final rating (N=157)

2. Participant Demographic and Transplant-related Clinical Characteristics

Table 2 presents the demographic and transplant-related clinical characteristics of the study participants. The average age of the participants was 52.6 years (range: 19 to 72), and 58.6% of them were male. Most participants were married, had less than high school education, had no job, and were covered by Korean Medicare.

Table 2.

Descriptive of Demographic and Transplant-related Clinical Characteristics (N=157)

Among the participants’ clinical characteristics, more than half had received hemodialysis (HD) in a dialysis clinic outside the OTC, and the average duration of dialysis was 7.72 years. With regard to transplant-related factors, the mean waiting time was 5.26 years, and most participants had been awaiting DDKT for 5 or more years, had negative PRA, and had not had a previous kidney transplant. The participants’ mean BMI was 23.62.

As to transplant-related physical candidacy, both the KTMI and RCRI scores of most participants were above the intermediate level and indicated intermediate- or high-risk physical candidacy. The mean KTMI score was 3.73, and the mean RCRI score was 2.01.

3. Predictors of High Psychosocial Risk

Table 3 shows the predictors of high psychosocial risk among the participants. The results showed that increased odds of high psychosocial risk were significantly associated with older age, female gender, not being married (“others” marital status), having a job, higher KTMI score, higher RCRI score, lower BMI (<18.5 kg/m²), shorter waiting time (<5 years), receiving dialysis outside the transplantation center, and previous kidney transplantation.

Table 3.

Factors Associated with High-Psychosocial Risk

When entered into a multivariate logistic regression model, two factors remained independently associated with high psychosocial risk; higher KTMI score (OR=8.62, p=.003) and older age (OR=7.37, p=.007) (Table 3). The likelihood ratio test of the binary logistic regression model indicated the statistical significance of the model with the covariates used (χ²=39.15, df=10, p<.001). In multivariate logistic regression analysis using three cut-off points, the classification accuracy, which indicates prediction accuracy of the model, was 76.4%. Therefore, the goodness of fit test was found to be suitable for the model.

4. ROC Curve Analysis of PACT Cutoff Points

As shown in Figure 1, the ROC curve analysis demonstrated the predictive power of PACT scores at different cutoff points: 2 and 3. The results of the ROC curve analysis were used to calculate the optimal PACT cutoff point indicating psychosocial risk for the Korean DDKT candidates. Specifically, when the AUC as a measure of predictive power was compared between the cutoff points of 3 and 2, the AUC of cutoff point 3 was higher (AUC=0.80; 95% CI=0.72-0.86) than that of cutoff point 2 (AUC=0.78; 95% CI=0.69-0.85). Thus, a PACT score of 3 as a cutoff point had greater predictive value for psychosocial risk among the Korean DDKT candidates and showed good discrimination as its AUC exceeded the 0.70 standard.

Figure 1.

Receiver operator curve (ROC) analysis for PACT cutoff points of 3 and 2.