The previous studies reported Type D was associated with poor quality of life (QoL), increased psychological distress, and impaired health status in cardiac patients. The aim of this study is to assess the relationships among Type D personality, illness perception, social support, and investigate the impact of Type D personality on QoL in continuous ambulatory peritoneal dialysis (CAPD) patients. Type D personality was assessed by the Chinese 14-item Type D Personality Scale (DS14). Illness perceptions were assessed using the Chinese version of the Brief Illness Perception Questionnaire (B-IPQ). Social support status was assessed by the well-validated social support rating scale (SSRS). Patients' QoL was assessed by using Medical Outcomes Short Form 36 (SF-36), respectively. The Type Ds had significantly lower objective support score (8.18 ± 2.56 vs. 9.67 ± 3.28, p = 0.0001), subjective support score (6.71 ± 2.0 vs. 7.62 ± 1.93, p = 0.0001) and utilization of social support score (6.76 ± 2.0 vs. 7.61 ± 1.94, p = 0.0001) than that of the non-type Ds. Type Ds believed their illness had much more serious consequences (7.67 ± 2.64 vs. 6.27 ± 3.45, p < 0.001), and experience much more symptoms that they attributed to their illness (6.65 ± 2.54 vs. 7.31 ± 2.36, p = 0.023). Significant differences were found between Type Ds and non-Type Ds in PCS (40.53 ± 6.42 vs. 48.54 ± 6.21 p < 0.001) and MCS (41.7 1 ± 10.20 vs. 46.35 ± 9.31, p = 0.012). The correlation analysis demonstrated that Type D was negatively associated with physical component score (PCS) (r = -0.29, p < 0.01), mental component score (MCS) (r = -0.31, p < 0.01), and social support (r = -0.24, p < 0.001). Using multiple linear regression analysis, we found that Type D personality was independently associated with PCS (β = -0.32, p < 0.001) and MCS (β = -0.24, p < 0.001). Type D personality was a predictor of poor QoL in CAPD patients. The current study is the first to identify a strong association among Type D, illness perceptions, social support and QoL in CAPD patients. The worse illness perceptions and lower social support level therefore represent possible mechanisms to explain the link between Type D and poor QoL in CAPD patients.
Keywords: Peritoneal dialysis; Type D personality; illness perception; quality of life; social support.