Anorectal fistula

Metadata

Name	Anorectal fistula (anorectal_fistula)
Category	Digestive
Sex
Adult	Yes
UUID	9562f212-7362-403f-9023-06f1537a0ece
Definition	An abnormal anatomical passage connecting the RECTUM to the outside, with an orifice at the site of drainage.

Ontologies

Disease Ontology (DOID)	DOID_0060328
GWAS Catalogue	HP_0010447
MeSH	D012003
SNOMED-CT	72779005
FinnGen	K11_FISSANAL

Key Summary Statistics

Cases from any source

Total	2938
Female (%)	1031 (35%)
Male (%)	1907 (65%)

Year first recorded

Cases linked in all UK Biobank sources

Cross-source concordance

Vertical bars correspond to number of cases per source/intersection; horizontal bars to left correspond to total number of cases per source.

Incidence & prevalence

Baseline prevalence stratified by sex

Female	36.07 (32.04,40.1)
Male	75.32 (68.98,81.66)

Incidence stratified by sex

Female	1.57 (1.24,1.9)
Male	3.35 (2.83,3.88)

Incidence stratified by age

Ages 40-44	3.33 (2.2,4.47)
Ages 45-49	2.91 (2.0,3.83)
Ages 50-54	3.12 (2.25,4.0)
Ages 55-59	2.46 (1.75,3.16)
Ages 60-64	1.81 (1.3,2.33)
Ages 65-69	1.61 (1.06,2.17)

Period prevalence

Methods

Comparison with general population

Sex-standardised prevalence from CALIBER study (Kuan et al. 2019)

Population	Ages 40-49	Ages 50-59	Ages 60-69
UK Biobank	76 (68,85)	83 (76,91)	69 (64,75)
CALIBER	63 (61,65)	70 (68,73)	65 (62,67)

Stratified by age and Townsend deprivation status

Deprivation status	Ages 40-49	Ages 50-59	Ages 60-69
Least deprived	76(57,99)	79(64,96)	61(50,73)
Low	72(53,95)	69(56,86)	66(55,78)
Medium	62(45,83)	78(63,95)	68(57,81)
High	94(75,117)	85(70,103)	71(59,85)
Most deprived	73(57,91)	104(87,123)	82(69,98)

Stratified by age and country

Country	Ages 40-49	Ages 50-59	Ages 60-69
England	70(62,80)	75(68,83)	65(59,71)
Scotland	102(76,135)	124(101,150)	104(85,126)
Wales	91(59,133)	94(69,125)	61(44,83)

Risk factors analysis

‘Healthy’ BMI, smoking status ‘never’, or no hypertension (absence of hypertension records) were considered as reference values.

Hazard Ratio (HR) values with P < 0.0002 were considered to show significant association with disease onset after correction for multiple-testing using the Bonferroni method

N=154022, Events=131

Factor	Level	Hazard Ratio	P value
BMI	overweight	1.27 (0.78, 2.07)	0.333
BMI	obese	2.62 (1.63, 4.22)	6.84e-05
BMI	underweight	0 (0, Inf)	0.992
smoking	previous	1.3 (0.9, 1.9)	0.166
smoking	current	1.71 (0.99, 2.95)	0.0544
hypertension	yes	1.97 (1.38, 2.82)	0.000171

Definition

UK Biobank field id	Description	Code	Value
41202	Diagnoses - main ICD10	K60.3	Anal fistula
41202	Diagnoses - main ICD10	K60.4	Rectal fistula
41202	Diagnoses - main ICD10	K60.5	Anorectal fistula
41204	Diagnoses - secondary ICD10	K60.3	Anal fistula
41204	Diagnoses - secondary ICD10	K60.4	Rectal fistula
41204	Diagnoses - secondary ICD10	K60.5	Anorectal fistula
41200	Operative procedures - main OPCS4	H55.1	Laying open of low anal fistula
41200	Operative procedures - main OPCS4	H55.2	Laying open of high anal fistula
41200	Operative procedures - main OPCS4	H55.3	Laying open of anal fistula NEC
41200	Operative procedures - main OPCS4	H55.4	Insertion of seton into high anal fistula and partial laying open of track HFQ
41200	Operative procedures - main OPCS4	H55.5	Fistulography of anal fistula
41200	Operative procedures - main OPCS4	H55.6	Probing of perineal fistula
41200	Operative procedures - main OPCS4	H55.7	Repair of anal fistula using plug
41210	Operative procedures - secondary OPCS4	H55.1	H55.1
41210	Operative procedures - secondary OPCS4	H55.2	H55.2
41210	Operative procedures - secondary OPCS4	H55.3	H55.3
41210	Operative procedures - secondary OPCS4	H55.4	H55.4
41210	Operative procedures - secondary OPCS4	H55.5	H55.5
41210	Operative procedures - secondary OPCS4	H55.6	H55.6
41210	Operative procedures - secondary OPCS4	H55.7	H55.7
40001	Underlying (primary) cause of death: ICD10	K60.3	Anal fistula
40001	Underlying (primary) cause of death: ICD10	K60.4	Rectal fistula
40001	Underlying (primary) cause of death: ICD10	K60.5	Anorectal fistula
40002	Contributory (secondary) causes of death: ICD10	K60.3	Anal fistula
40002	Contributory (secondary) causes of death: ICD10	K60.4	Rectal fistula
40002	Contributory (secondary) causes of death: ICD10	K60.5	Anorectal fistula
42040	GP clinical event records	7729700.0	Closure of rectal fistula
42040	GP clinical event records	7738000.0	Laying open of low anal fistula
42040	GP clinical event records	7738100.0	Laying open of high anal fistula
42040	GP clinical event records	7738200.0	Laying open of anal fistula NEC
42040	GP clinical event records	7738300.0	Insertion seton in high anal fistula+part lay open track HFQ
42040	GP clinical event records	7738400.0	Fistulography of anal fistula
42040	GP clinical event records	7738600.0	Excision of fistula in ano
42040	GP clinical event records	7738611.0	Excision of anal fistula
42040	GP clinical event records	7738.11	Anal fistula operations
42040	GP clinical event records	7738900.0	Repair of anal fistula using plug
42040	GP clinical event records	J531000	Sub-mucosal anal fistula
42040	GP clinical event records	J531100	Inter-muscular anal fistula
42040	GP clinical event records	J531200	Ano-rectal fistula
42040	GP clinical event records	J531300	Rectal fistula
42040	GP clinical event records	J531.00	Fistula-in-ano
42040	GP clinical event records	J531z00	Fistula-in-ano NOS
42040	GP clinical event records	J53..00	Anal fissure and fistula
42040	GP clinical event records	J53z.00	Anal fissure and fistula NOS
42040	GP clinical event records	XaPpU	Repair of anal fistula using plug