Characteristics of anorectal motility in elderly patients with functional defecation disorders / 中华老年医学杂志

ABSTRACT

Objective:To investigate the characteristics of anorectal dynamics in elderly patients with functional defecation disorders(FDD), and to provide a basis for their diagnosis, treatment and prevention.Methods:In this retrospective study, 226 patients with FDD receiving 3D high-resolution anorectal manometry were divided into an elderly group(93 cases)and a non-elderly group(133 cases). Results from anorectal manometry parameters were compared and analysis of patterns of anorectal pressure changes in elderly participants based on sex, the Bristol stool classification and clinical symptoms was conducted.Results:The resting anal pressure, rectal pressure and anal relaxation rate were lower( t=-3.407, -2.051, Z=2.548, P=0.001, 0.040, 0.011)and the volume of first sensation was higher( t=1.998, P=0.047)in the elderly group than in the non-elderly group.The maximum anal squeezing pressure, residual anal pressure and maximum tolerated volume were higher( t=4.589, 4.730, 2.025, all P<0.05), whereas the anal relaxation rate and anorectal pressure gradient were lower in elderly men than in elderly women( Z=4.059, t=-3.714, P<0.001 for both). Regarding the types of FDD, both the elderly group and the non-elderly group were dominated with type Ⅱ defecation disorder, with more men than women having type Ⅱ defecation disorder in the elderly group( χ2=10.343, P=0.001). In cases of paradoxical sphincter contraction during simulated defecation, the incidence in the elderly group was 80.65%(75/93), which was higher than 68.42%(91/133)in the non-elderly group( χ2=4.194, P=0.041). The volume of first sensation, volume of first defecation sensation, and maximum tolerated volume of patients in the elderly group without the urge to defecate were(59.86±23.84)ml, (96.76±34.61)ml, and(144.32±30.57)ml, respectively, higher than those of patients with the urge to defecate(46.79±17.20)ml, (75.26±28.75)ml, and(120.00±40.28)ml( t=-2.241, -2.493, -2.891, P=0.027, 0.014, 0.005). The rectal pressure(26.52±16.08)mmHg of patients with defecation dyssynergia was lower than that of patients without defecation dyssynergia(39.91±8.82)mmHg(1 mmHg=0.133 kPa)( t=-3.128, P=0.002), while the resting anal pressure of patients with defecation dyssynergia(90.60±28.44)mmHg was higher than that of patients without defecation dyssynergia(73.65±27.10)mmHg( t=-2.201, P=0.030). The resting anal pressure and maximum anal squeezing pressure in patients with anal blockage sensation[(87.11±24.64)mmHg, (149.28±48.29)mmHg]were higher than those in patients without anal blockage sensation[(72.43±20.02)mmHg, (121.76±26.35)mmHg]( t=2.954、3.066, P=0.004、0.003). There was no significant difference in values from parameters of anorectal dynamics between patients with different Bristol stool types, with and without incomplete defecation or with different degrees of abdominal distension(all P>0.05). Conclusions:Anorectal dynamics in patients with FDD are characterized by paradoxical anal sphincter movements, but older patients with FDD are mainly characterized by inadequate rectal propulsion, pelvic floor muscle dysfunction and reduced rectal sensitivity.