People with spina bifida use their MACE on long-term follow-up: A single institutional retrospective cohort study

Abstract

While the Malone antegrade continence enema (MACE) facilitates bowel movements in patients with spina bifida (SB) and neuropathic bowel, little is known about its long-term use. We aimed to assess long-term MACE use and potential risk factors for disuse. All patients with SB who underwent MACE procedures at our institution were retrospectively reviewed. Main outcome was MACE disuse (no longer catheterizing the MACE for antegrade enemas) based on self-report on a clinic questionnaire, or medical record for patients last seen before introducing the questionnaire 5 years ago. Survival analysis used two timeframes: time after surgery (Analysis 1) and chronological age: accounting for older children reaching adulthood earlier (Analysis 2). Overall, 411 patients (54% female, 78% shunted, 65% augmented) underwent a MACE procedure at median 7.9 years old (median follow-up: 8.4 years). Thirty-three (8%) patients no longer used their MACE. Most common reasons for doing so were channel/stomal stenosis (61%) and excision at colostomy or other abdominal surgery (12%). Bowel management afterwards included oral agents±enemas (55%), Chait tube (30%), colostomy (12%). After correcting for differential follow-up, 90% of participants used their MACE at 10 years and 87% at 15 years after surgery. Based on chronological age, 97% used their MACE at 15 years old, 92% at 20 and 81% at 30 (Summary Figure). On multivariate analysis, umbilical MACEs were 2.4 times more likely to be disused than right lower quadrant MACEs (p=0.04). Without correcting for chronological age (Analysis 1), patients undergoing MACE surgery at older ages were more likely to stop MACE use (p=0.03). However, after accounting for chronological age (Analysis 2), patients undergoing a MACE procedure at older ages were no more likely to stop its use (p=0.47, Figure). Gender, SB type, shunt status, mobility status, bladder augmentation or a urinary catheterizable channel were not associated with stopping MACE use (p≥0.10). Participants were regularly followed in multi-disciplinary SB clinics. We did not assess continence, satisfaction or long-term urinary channel use, making it premature to recommend optimal stomal locations. Most patients with SB followed by a multi-disciplinary team continue using their MACE; 1% stopped MACE use annually, particularly after adolescence. This strongly suggests it is an effective bowel management method and transitioning to self-care plays a role in maintaining long-term MACE use. Umbilical MACEs may be at high risk of disuse, but all people with a MACE can benefit from support as they transition to adult care.