EFFECT OF RACE, GENDER AND BODY POSITION ON THE PREVALENCE AND TYPE OF DYSSYNERGIC DEFECATION Askin Erdogan, Kulthep Rattanakovit, Yeong Yeh Lee, Siegfried Yu, Satish SC Rao Medical College of Georgia, Georgia Regents University, Augusta, Georgia. BACKGROUND AIM METHODS CONCLUSIONS Dyssynergic defecation (DD) affects 30% of patients with chronic constipation. Whether the prevalence of DD is influenced by factors such as race, gender and body position are not known. To assess the effects of race, gender, and body position on (i) DD and its subtypes and (ii) on balloon expulsion time, in a consecutive series of constipated patients. Consecutive patients with chronic constipation (Rome III) and suspected to have DD were enrolled. Patients were evaluated with high resolution anorectal pressure topography using a 12 sensor probe and balloon, (Given Imaging, Yoqneam, Israel, figure 1). Pressure topographic changes in rectum and anal canal when bearing-down on-bed and on-commode (60-cc balloon distention) were assessed. A balloon expulsion test (BET) was also performed with a 50 ml water filed balloon (Fig 2); abnormal BET= > 60sec. Unpaired t test and Chi-square test were used. RESULTS The prevalence of DD and its subtypes were similar between Caucasians and African Americans. The prevalence of DD subtypes was influenced by gender. (Type I Male > Female, Types III and IV Female > Male). BET was affected by race (African Americans had more prolonged BET). Body position influences both the presence of and type of DD pattern, and is also affected by gender, but not by race. Hence the best method to assess dyssynergia is to have the subject attempt defecation on a commode. 185/199 screened patients (F/M=148/37, Caucasians/African Americans= 131/54, mean age 50.2 yrs) enrolled. Mean age was similar in Caucasians vs African Americans (48.9 vs 53.3 yrs, p=0.1), and women vs men (50.6 vs 48.2 yrs, p=0.5). The percentage distribution of Types I, II, III and IV DD patterns and normal pattern for caucasians and African Americans on-bed was similar (p=0.5, Table). The percentage distribution of Type I, II, III and IV DD patterns and normal pattern for caucasians and African Americans on-commode were different compared to on-bed but similar between 2 races (p=0.9). The percentage of normal defecation pattern was higher on-commode vs on- bed for Caucasians and African Americans (Table). Mean BET (sec) for African Americans was significantly higher (p=0.04) than Caucasians; 133.9±17.9 vs 95.4±9.7. However there was no significant difference between Caucasians vs African Americans regarding prevalence of normal and prolonged BET (p=0.2). The percentage distribution of Type I pattern was higher and Type III, and IV and normal pattern were lower for men vs women on-bed (p=0.0035) but not on- commode (p=0.6, Table). Mean BET for men and women was similar (p=0.7). There was no significant difference between men and women regarding prevalence of normal and prolonged BET (p=0.8). RESULTS TableType of Dyssynergic defecation on bed (%) Type of Dyssynergic defecation on commode (%) Mean BET (sec) % of BET abnormal patients * = p<0.05 I II III IVNormal I II III IVNormal Caucasians *40 African Americans *50.9 Female25.7* *22.3*10.1* Male56.8* *8.1*5.4* Fig 3 : High-resolution and Waveform Manometry images displaying Dyssynergic defecation Types I – IV Fig 1 : 12 sensor probe and balloon Fig 2 : 50 ml water-filled balloon and probe for BET Bearing down Fig 4 : HRM image in 1 subject showing dyssynergia while bearing down on bed(Lt.) and normal relaxation on commode(Rt.). On BedOn Commode