Women seeking fistula repair services between September 2007 and September 2010 were recruited for this prospective cohort study at 11 sites in five countries; Bangladesh (three sites), Guinea (one site), Niger (two sites), Nigeria (three sites) and Uganda (two sites). Study sites included a mix of public, private, and faith-based institutions located in both urban and rural settings. All were receiving support to conduct fistula repairs from EngenderHealth’s Fistula Care project. The study protocol was reviewed and approved as required by institutional and government guidelines. Approvals were obtained from the Comite National D’Ethique pour la Recherché en Santé in Guinea; the Ministere de la Sante Publique in Niger; the National Health Research Ethics Committee, the Kebbi State Ministry of Health, the Sokoto State Ministry for Women Affairs, and the Zamfara State Hospital Services Management Board in Nigeria; and the National Council for Science and Technology in Uganda. The Bangladesh Medical Research Council declined to review the study due to its observational nature.
Women were eligible for the study if they freely consented to participate and signed an informed consent form, had a urinary fistula or rectovaginal fistula (RVF) (obstetric or traumatic in origin) and agreed to attend one follow-up visit three months following their fistula repair surgery. Women were excluded if they did not consent to participate, had incontinence unrelated to a fistula, or had a condition, which in the opinion of the site investigator prevented her from undergoing fistula repair surgery or contraindicated her participation in the study. Urinary fistula was broadly defined as an abnormal connection/communication between the genital and urinary tracts, including vesicovaginal (VVF), vesicouterine, urethrovaginal, and ureterovaginal fistula. Given that genital fistula does occur in young women/girls we did not have a lower age limit for study participation. Status as a “minor” was determined in accordance with legal age of adulthood in each country. Proxy consent was based on each country’s legislation and, where appropriate, was obtained from a relevant legal authority (i.e. parent or guardian). Proxy consent did not substitute for the minor’s consent, but rather supplemented it.
Given the observational nature of the study, no new interventions were introduced and clinical procedures were not standardized within or across sites for study purposes. Care of patients before, during and after their fistula repair surgery was at the discretion of the surgeon and other site staff. Repair surgeries were conducted either by trained fistula surgeons or by surgeons being trained to repair fistulas under the guidance of a fistula surgery trainer. The surgeons included some who were based at the study sites and others who were surgeons visiting the sites during focused outreach efforts.
Data were collected on standardized forms during participant’s hospital stay and at the 3 month follow-up exam. Interviews were carried out at admission, discharge and follow-up in English, French or local languages. Participants were given funds to cover their return transport for the follow-up visit, and at most sites a small gift to express our appreciation that they had returned for follow-up (e.g. a blanket, fabric for making a dress or a carrying basket). As is the standard practice at all study sites, repair services and follow-up care were provided at no cost.
The primary outcome was fistula closure 3 month postsurgery, determined by pelvic examination, with a dye test in women who had urine leakage. If no pelvic examination or dye test was conducted (186/1274, 14.6%) fistula closure was determined by providers’ response to the question “Does the client have continuous and uncontrolled leakage of urine.” The secondary outcome was residual incontinence among women with a closed fistula 3 month post-surgery. Residual incontinence, including overflow, stress and urge incontinence, was determined by the surgeons based on the participants history and clinical examination findings; additional specialized diagnostics were not done in most cases.
The potential predictors of fistula closure and residual incontinence included patient characteristics, fistula characteristics, and context of repair. Patient characteristics included age and years living with the fistula (both continuous variables), rural residence, education (dichotomized at primary education or higher), parity (dichotomized at greater than three), whether the patient had delivered via c-section, whether or not the patient had previously undergone surgery for the fistula, and whether the patient had female genital cutting (FGC). FCG status was assessed during a clinical exam; data for the other variables were derived from the participant interviews. Comorbidities assessed included malnutrition, determined through skin-fold measurement, body mass index or visual assessment; anemia, determined through hemoglobin level, hematocrit or visual assessment; and other conditions as reported by clinicians.
Fistula characteristics assessed included fistula location, bladder size (dichotomized as small versus normal or distended), fistula size, degree of scarring (none/mild, moderate or severe), number of fistulas (dichotomized at greater than one), ureter involvement (yes or no), and degree of urethral involvement. Urethral involvement was categorized as “partial” (urethra involved but not completely destroyed or separated), and “complete destruction or circumferential,” where circumferential referred to complete separation of the urethra from the bladder. Because there are no agreed upon standard definitions or objective measure for most of the fistula characteristics assessed, the operating surgeon made subjective assessments based on their clinical judgment and experience.
Variables related to context of repair included whether the repair was conducted during routine services or an outreach activity and whether it was conducted during a training session, as well as surgeon experience. Surgeon experience was measured by the number of complex repairs the surgeon reported ever conducting; complex was defined subjectively by each surgeon, and the variable was dichotomized at greater than 200 complex repairs.
For bivariable analyses, patient, fistula and contextual correlates of surgery outcome were compared using risk ratios (RRs) and corresponding 95% confidence intervals (CIs); these were derived using generalized estimating equations (GEE), accounting for clustering of patient outcomes within facilities. RRs and corresponding 95% CIs were generated using the logarithm link function and binomial distribution specification in SAS PROC GENMOD.(28
Variables eligible for inclusion in multivariable models were conceptually associated with repair outcomes and statistically associated (p-value <0.20) with repair outcomes in bivariable analysis. In the event that variables were too highly correlated (r >0.4) only one was included. For example, prior repair was included instead of fistula duration. Multivariable GEE models using the log-binomial specification in GENMOD were used to generate adjusted RRs (ARR) and corresponding 95% CIs; where the log-binomial model failed to converge, SAS PROC GENMOD’s Poisson regression capability with a log link function and robust variance was used.(29
) All data were analyzed using SAS version 9.2.