Table 5.

Results of studies reporting on PWS and urological diseases, symptoms or congenital anomalies with more than one patients.

Author (year)	Study design	Method	Baseline characteristics:	Results	Limitations/remarks
Von Gontard et al. (2010) (100)	Cohort study	Questionnaire filled in by parents/caregivers	N=118 Age: mean 20.5 (SD ±11.5, range 5-45) years BMI: NA Gender: NA Genotype: 32 del, 27 mUPD, 3 ICD, 56 other/unknown	16 out of 118 patients (14%) had nocturnal enuresis of whom nine (56%) between the age of 5-12. Only four adults (7%) experienced nocturnal enuresis. A total of five out of 118 patients (4%) had additional daytime urine incontinence. The mean age in this group was 21.4 (SD ±14.8) years. Urgency symptoms were seen in nine out of 16 patients (60%) with nocturnal enuresis. Five out of 16 patients (32%) had a history of UTIs and only 2 (13%) a history of UTIs with fever.
Sinnema et al. (2012) (101)	Retrospective cohort study	Semi-structured interviews with patient and main caregivers, questionnaire filled in by parents/caregivers.	N=12 Age: mean 57.8 (SD ±6.2, range 50-66) years BMI: 31.5 (SD ±5.,0 range 23.4-37.1) kg/m2 Gender: 5M, 7F Genotype: 4 del, 8 mUPD	Kidney malformations were present in only one out of 12 (8%) patients, which was a bilateral duplication of the kidney and ureter system.	Study population overlapping with Sinnema et al., 2011 (17).
Equit et al. (2013) (102)	Cross-sectional study	Questionnaires filled in by parents/caregivers of self-help groups. Comparison with patients with fragile X-syndrome.	N=191 Age: mean 20.0 (SD ±10.5) years BMI: NA Gender: 104M, 87F Genotype: NA	56 out of 191 patients (29%) had at least one elimination disorder. - 42 out of 191 (22%) suffered from nocturnal enuresis and 23 patients (12%) from daytime urinary incontinence. Daytime urinary incontinence was more prevalent in patients with fragile X-syndrome than PWS (p<0001). The prevalence of elimination (NE, DIU or FI) disorders decreased with increasing age. - At age 4-12 had 18 out of 54 (33%) at least one elimination disorder, at age 13-17, this was 16 out of 47 (34%), at age 18-30 15 out of 60 (25%) and 30 years or older six out of 29 (21%) Urgency symptoms were present in 49 out of 191 (26%) of patients with PWS. 42 out of 191 (22%) were previously diagnosed with UTIs. More patients with PWS had have previous UTI’s compared to fragile X syndrome (42 out of 191 (22%) versus 18 out of 166 (11%), p=0.005).	Return rate of 48.9% for patients with PWS might have led to selection bias.
Meinhardt et al. (2013) (103)	Retrospective observational study	Data collected on anthropometric measurements, laboratory results and DXA scans at baseline, after one year and at last observation.	N=41 Age: mean 3.8 (SD ±3.0, range 0.4-12.2), years BMI: mean 0.6 (SDS ±1.9) Gender: 22M, 19F Genotype: NA GHt: all, none treated before study	One patient (2%) suffered from a severe UTI and convulsion during GHt after which treatment was stopped after 2.4 years and patient fully recovered.
Torrado et al. (2013) (104)	Retrospective cohort study	Data collected from medial reports of PWS compared. Prevalences of birth defects in PWS compared to general population by collecting data from multiple population registries.	N=180 Age at diagnosis 1.2 (range 0.01-17.25) years BMI: NA Gender: 93M, 87F Genotype: 109 del, 68 mUPD, 3 ICD	Five out of 180 patients (3%, one female and four males) had congenital reno-ureteral malformation; left renal hypoplasia, bilateral ureteral duplication, left bifid renal pelvis, vesicoureteral reflux, left pelvicalyceal dilatation and bilateral vesicoureteral reflux caused by ureteral valves. The prevalence of reno-ureteral malformations was significantly higher than in the general population in national and international registries (p<0.05). No association between genotype and congenital malformations was found (three del vs two non del, p=1.00).
Pacilli et al. (2018) (105)	Cohort study	Data collected from patient records from the Victorian PWS Register.	N=33 Age: range 6 months – 17 years BMI: NA Gender: all male Genotype: NA	One out of 33 (3%) patients that underwent orchidopexy was diagnosed with a horseshoe kidney.
Chao et al. (2021) (34)	Retrospective observational study	Data collection on patient characteristics and presence of LUTS. Assessments of LUTD by uroflowmetry, postvoid residual urine (PVR) by abdominal ultrasound. LUTD defined as abnormal uroflow, low peak flow rate (Qmax) or elevated PVR. Videourodynamic studies were performed in some cases.	N=37 Age: mean 17.7 (SD ±7.8, range 5-34) years BMI: mean 28.5 (SD ±11.2) kg/m2 Gender: 15M, 22F Genotype: 16 del, 3 mUPD, 18 unknown	Ten out of 37 patients (27%) had LUTS. The urodynamic tests were abnormal in 17 out of 34 (50%) of patients. Abnormal uroflowmetry pattern (nonbell shaped) was significantly more prevalent in those with LUTS than without (6 out of 8 (75%) versus 6 out of 20 (23%) respectively, p=0.0049). In patients with LUTS (n=10), 4 (40%) had daytime UI, 2 (20%) both daytime and nighttime UI, one (10%) had nocturnal enuresis and three (30%) LUTS without UI. In 10 out of 20 patients (50%) PVR was increased for their age. Qmax, voided volume and bladder capacity were significantly higher in those without LUTS (24.0 (9.0) vs 14.4 (13.5) ml/s, p=0.0046; 240.6 (124.0) vs 126.4 (91.8) ml, p=0.0142 and 247.7 (123.2) vs 143.5 (121.1) ml, p=0.0151 respectively). In three LUTS patients in whom videourodynamic studies were performed, all showed detrusor sphincter dyssynergia.	Low compliance to PVR (54%).

Body mass index (BMI), congenital anomalies of the kidney and urinary tract (CAKUT), daytime urinary incontinence (DIU), deletion (del), dual-energy X-ray absorptiometry (DXA), fecal incontinence (FI), female (F), growth hormone treatment (GHt), imprinting center defect (ICD), lower urinary tract dysfunction (LUTD), lower urinary tract symptoms (LUTS), male (M), maternal uniparental disomy (mUPD), nocturnal enuresis (NE), not available (NA), Prader-Willi syndrome (PWS), postvoid residual urine (PVR), standard deviation (SD), urinary incontinence (UI), urinary tract infection (UTI).