The Clinical Characteristics of Patients with Chronic Idiopathic Anal Pain

The aim of this study was to investigate the clinical characteristics, treatment outcomes and psychological distress in patients with chronic idiopathic anal pain. The study was conducted on patients referred to Hangzhou Third Hospital for chronic anal pain from January, 2010 to December, 2014. Patient demographics, clinical history, anorectal physiology, and radiological imaging data were recorded for all patients. The treatment outcome was noted for patients treated and followed up for more than 6 month at the present unit. Ninety-six patients with mean age of 45.1 years (range, 17-82) were studied. Seventy-one patients (74.0%) had functional anorectal pain(FARP). The main complaints were dull, sharp, stabbing, or spasm pain. Among all patients, 34.3% reported that their pain radiated into other locations. Fifty-one patients (53.1%) had bowel dysfunction, while 28.1% patients had urinary dysfunction. The common factors associated with pain relief were day time, lying down and warm water baths; the factors that contributed to aggravated pain were night time, defecation or sitting. 92.7% (89/96) of patients reported symptoms of psychological disturbance. FARP patients exhibited increased depression than non-FARP patients(P<0.05). In addition, female patients were more likely to have depression than male patients (P<0.05). The overall pain treatment success rate was 55.2% (53/96). The pain treatment outcome was better in non-FARP patients than in FARP patients(χ2=3.85, P<0.05). Conclusively, chronic idiopathic anal pain is a complex clinical symptom, involving pelvic floor muscles, the nervous system, endocrine system, and the patients' psychological conditions. Further research is needed to improve diagnosis and treatment for patients with chronic idiopathic anal pain.