Of 378 patients in our registry, 297 patients met our inclusion criteria: 147 (49%) women reported FTRP with defecation only, and 150 (51%) women reported FTRP during other times. We found that women with defecation only FTRP were younger (median [IQR] age: 64 [48, 74] vs. 71.5 [63, 79]); baseline ODS score was higher in women with defecation only FTRP (median [IQR]: 9 [5, 13] vs. 7 [4, 10], p<0.001), while Wexner score was higher in women with FTRP during other times (median [IQR]: 12 [3, 16] vs. 15 [12, 18], p<0.001). Women with defecation only FTRP were more likely to have symptoms longer than 6 months (86% vs 73%, p=0.006). Additional patient characteristics including comorbidities and obstetrics history were comparable and are included in Table 1.
Among the full cohort, a sub-cohort of 117 patients were able to complete an MRD (Table 2a). For linear measurements of the pelvic floor, we found that women with defecation only FTRP have shorter H line at rest (median [IQR], cm: 6 [5.3, 6.7] vs. 6.5 [5.7, 7.1], p<0.001), more acute resting anorectal angle (median [IQR]: 109 [93, 120] vs. 118 [102, 130], p=0.02), and lower resting width of levator hiatus (median [IQR], cm: 6 [5.3, 6.7] vs. 6.5 [5.7, 7.1], p<0.001). Women with defecation only FTRP also have a smaller eLASV (median [IQR] cm3: 27 [17, 50] vs. 42 [27, 58], p=0.008). There are no significant differences between the distribution of type of rectal prolapse between the two groups, with similar percent of patients categorized as intra-anal RP (78% vs. 88%, p=0.21). Women with defecation only FTRP are less likely to have an open anal canal at rest (31% vs. 58%, p=0.004) and more likely to have a rectocele present (71% vs. 50%, p=0.02). There are no significant differences observed between the 2 groups for anterior and middle compartment anatomical structures and levator ani muscle characterization.
Among the full cohort, a sub-cohort of 67 patients were able to complete an 2D ARM (Table 2b). Women with defecation only FTRP had higher resting pressures (median [IQR]: 33 [16, 53] vs. 20 [16, 27], p=0.03), longer duration of sustained squeeze (median [IQR], sec: 11 [5, 17] vs. 6 [4,10], p=0.04), and higher intrarectal pressure during attempted defecation (median [IQR]: 44.4 [29.6, 59.5] vs. 33.2 [27.3, 41.0], p=0.04). The 2 groups had similar length of high-pressure zone, squeeze pressures, and percent of anal relaxation during attempted defecation. The 2 groups took similar time to expel the balloon in the BET.
In multivariable models, higher H line at rest (aOR [95% CI]: 1.5 [1.0, 2.2]) and during defecation (aOR [95% CI]: 1.4 [1.1, 1.8]), as well as higher eLASV were associated with increased odds of FTRP during other times (Table 3).