Risk factors for acute and chronic postoperative pain in patients with benign and malignant renal disease after nephrectomy.

AIMS: This longitudinal study was performed in order to analyze the incidence of and perioperative risk factors for the development of chronic postsurgical pain (CPSP) in patients after nephrectomy.
METHODS: For baseline data acquisition, valid instruments were used for scoring sociodemographic, psychological, psychosocial, pain, pain treatment, and comorbidity factors: the Mainz Pain Staging System (MPSS) for pain chronicity, the Chronic Pain Grading Questionnaire (CPGQ), the Neuropathic Pain Scale (NPS), the Hospital Anxiety and Depression Scale (HADS), the Short Form 12 (SF-12) for health-related quality of life, the Habitual Well-Being Questionnaire (HWBQ), the Symptom Check List (SCL-8) for detecting psychosomatic dysfunction, and the Weighted Illness Check List (WICL) for evaluation of comorbidities and their impact on activities of daily living. Pain intensities were recorded over the first 6 postoperative days after nephrectomy. A sample of 35 patients was followed up for 3 and 6 months.
RESULTS: Patients with more intense postoperative pain during the first 6 days had significantly higher preoperative anxiety scores. The incidence of CPSP 3 and 6 months after nephrectomy was 28.6% and 8.6%, respectively. Preoperatively increased anxiety scores, reduced physical health-related quality of life (SF-12), multiple comorbid conditions, and increased comorbidity-related disability were significantly associated with the occurrence of CPSP after 3 months. These patients also reported more severe pain during the first week after surgery. Preoperative "current pain intensity" was significantly increased in CPSP patients.
CONCLUSIONS: Our results demonstrate a multifactorial development of CPSP. This process may contribute not only to the occurrence of chronic postsurgical pain but also to the biopsychosocial impairment in these patients as often seen in other chronic pain populations.