Understanding outcomes after transplant requires a biopsychosocial model that includes biomedical and psychosocial factors. The latter, to date, are assessed only in a limited way as part of transplant registries or cohort studies.
The Swiss Transplant Cohort Study (STCS) is a nationwide open cohort study (starting May 2008) to systematically and prospectively assess psychosocial factors. This article describes the framework underpinning STCSs psychosocial assessment.
The STCS framework was adapted from the multidimensional conceptual perspective of Dew et al to describe transplant psychosocial domains and specific outcomes by adding a time perspective, a system perspective, and interaction among domains.
We propose a multidimensional, multilevel biopsychosocial framework representing mutually influencing domains from before to after transplant, and exemplify each domain by factors included in STCS and their measurement. The transplant patient, centrally positioned, is described by clinical and sociodemographic characteristics (eg, socioeconomic status, educational, professional, and relationship status).
The following psychosocial domains further describe the patient: (1) physical/functional (eg, perceived health status, sleep quality, daytime sleepiness), (2) psychological (eg, depression, stress), (3) behavioral (eg, medication adherence, smoking, drug use, physical activity, sun protection), (4) social (eg, work capacity/return to work), and (5) global quality of life.
Factors associated with health care system level (eg, trust in transplant team) are also included in the model. Conclusion The STCSs psychosocial framework provides a basis for studying the interplay of biomedical, sociodemographic, psychosocial, behavioral, and health care system factors in view of transplant outcomes and therefore has the potential to guide biopsychosocial transplant research. (Progress in Transplantation. 2013; 23:xxx-xxx)
Context Daytime sleepiness in kidney transplant recipients has emerged as a potential predictor of impaired adherence to the immunosuppressive medication regimen. Thus there is a need to assess daytime sleepiness in clinical practice and transplant registries. Objective To evaluate the validity of a single-item measure of daytime sleepiness integrated in the Swiss Transplant Cohort Study (STCS), using the American Educational Research Association framework. Methods Using a cross-sectional design, we enrolled a convenience sample of 926 home-dwelling kidney transplant recipients (median age, 59.69 years; 25%-75% quartile [Q25-Q75], 50.27-59.69), 63% men; median time since transplant 9.42 years (Q25-Q75, 4.93-15.85). Daytime sleepiness was assessed by using a single item from the STCS and the 8 items of the validated Epworth Sleepiness Scale. Receiver operating characteristic curve analysis was used to determine the cutoff for the STCS daytime sleepiness item against the Epworth Sleepiness Scale score. Results Based on the receiver operating characteristic curve analysis, a score greater than 4 on the STCS daytime sleepiness item is recommended to detect daytime sleepiness. Content validity was high as all expert reviews were unanimous. Concurrent validity was moderate (Spearman ρ, 0.531; P < .001) and convergent validity with depression and poor sleep quality although low, was significant (ρ, 0.235; P <.001 and ρ, 0.318, P =.002, respectively). For the group difference validity: kidney transplant recipients with moderate, severe, and extremely severe depressive symptom scores had 3.4, 4.3, and 5.9 times higher odds of having daytime sleepiness, respectively, as compared with recipients without depressive symptoms. Conclusion The accumulated evidence provided evidence for the validity of the STCS daytime sleepiness item as a simple screening scale for daytime sleepiness.
( Progress in Transplantation. 2013;23:xxx-xxx)
Context Poor sleep quality and poor daytime functioning affect many kidney transplant patients.
Objective To evaluate the validity of 2 items assessing sleep quality and daytime functioning using the Pittsburgh Sleep Quality Index as reference standard before use in a large cohort study, following the American Psychological Associations guidelines.
Design A cross-sectional study using a psychosocial questionnaire developed for a large cohort study and the Pittsburgh Sleep Quality Index.
Sample and Setting One hundred thirty-five home-dwelling kidney transplant patients aged 21 to 76 years (mean, 51.6 years; SD, 11.9 years).
Main Outcome Measures Evidence on content, internal structure, and relation to other variables.
Results The Pittsburgh Sleep Quality Index indicated a 47.4% prevalence of poor sleep quality; the sleep quality item in the psychosocial questionnaire showed a 30.7% prevalence of poor sleep quality and a 34.1% prevalence of poor daytime functioning. Content validity was good for the psychosocial questionnaires sleep quality item but poor for its daytime functioning item. As hypothesized, the psychosocial questionnaires sleep quality item was moderately correlated with its daytime functioning item (Spearman rho, ρs = 0.520, P < .001), indicating related but distinct concepts. When combined, the 2 items from the psychosocial questionnaire showed significant correlations with the total score on the Pittsburgh Sleep Quality Index ( ρs = -0.784, P < .001), depressive symptoms ( ρs = -0.680, P < .001), perceived health status ( ρs =0.619, P <.001), and subjective health status ( ρs =0.671, P <.001) in the expected directions.
Conclusion For kidney transplant patients, validity is strong for the psychosocial questionnaires sleep quality item, but the mixed findings regarding the validity of the daytime functioning item suggest that additional items are needed to measure daytime functioning. ( Progress in Transplantation. 2011;21)