Appendicitis

Metadata

Name	Appendicitis (appendicitis)
Category	Digestive
Sex
Adult	Yes
UUID	15b62403-cdb4-4d54-ad22-4d0077db6b5c
Definition	A gastrointestinal system infectious disease that involves inflammation and infection of the appendix caused by the blockage of the lumen with a small, hard piece of stool, a foreign body or worms. Mucus backs up in the appendiceal lumen, causing bacteria that live inside the appendix to multiply. The infection has_symptom pain, in the upper abdomen initially and later in the lower abdomen, has_symptom nausea, has_symptom vomiting and has_symptom fever.

Ontologies

Disease Ontology (DOID)	DOID_8337
GWAS Catalogue	EFO_0007149
MeSH	D001064
SNOMED-CT	74400008
FinnGen	K11_APPENDIX

Key Summary Statistics

Cases from any source

Total	18448
Female (%)	10336 (56%)
Male (%)	8112 (44%)

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	492.26 (477.7,506.81)
Male	462.12 (446.72,477.51)

Incidence stratified by sex

Female	6.39 (5.72,7.06)
Male	5.37 (4.7,6.05)

Incidence stratified by age

Ages 40-44	7.89 (6.1,9.67)
Ages 45-49	4.89 (3.69,6.1)
Ages 50-54	6.25 (4.99,7.52)
Ages 55-59	6.52 (5.35,7.7)
Ages 60-64	5.27 (4.36,6.17)
Ages 65-69	5.66 (4.59,6.73)

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	379 (360,398)	401 (386,417)	395 (382,408)
CALIBER	689 (682,696)	795 (787,803)	854 (844,863)

Stratified by age and Townsend deprivation status

Deprivation status	Ages 40-49	Ages 50-59	Ages 60-69
Least deprived	385(341,433)	403(369,439)	420(392,450)
Low	399(354,449)	406(372,443)	385(358,413)
Medium	367(325,413)	401(367,437)	377(349,405)
High	391(351,434)	381(349,416)	384(355,415)
Most deprived	357(322,395)	413(379,449)	411(380,444)

Stratified by age and country

Country	Ages 40-49	Ages 50-59	Ages 60-69
England	347(327,367)	340(324,356)	332(319,346)
Scotland	649(580,724)	849(789,912)	915(859,974)
Wales	289(231,358)	252(211,299)	243(208,283)

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
20002	Non-cancer illness code, self-reported	1502	appendicitis
41202	Diagnoses - main ICD10	K35	Acute appendicitis
41202	Diagnoses - main ICD10	K36	Other appendicitis
41202	Diagnoses - main ICD10	K37	Unspecified appendicitis
41204	Diagnoses - secondary ICD10	K35	Acute appendicitis
41204	Diagnoses - secondary ICD10	K36	Other appendicitis
41204	Diagnoses - secondary ICD10	K37	Unspecified appendicitis
41200	Operative procedures - main OPCS4	H01	Emergency excision of appendix
41200	Operative procedures - main OPCS4	H01.1	Emergency excision of abnormal appendix and drainage HFQ
41200	Operative procedures - main OPCS4	H01.2	Emergency excision of abnormal appendix NEC
41200	Operative procedures - main OPCS4	H01.8	Other specified emergency excision of appendix
41200	Operative procedures - main OPCS4	H01.9	Unspecified emergency excision of appendix
41200	Operative procedures - main OPCS4	H02	Other excision of appendix
41200	Operative procedures - main OPCS4	H02.1	Interval appendicectomy
41200	Operative procedures - main OPCS4	H02.2	Planned delayed appendicectomy NEC
41200	Operative procedures - main OPCS4	H02.3	Prophylactic appendicectomy NEC
41200	Operative procedures - main OPCS4	H02.8	Other specified other excision of appendix
41200	Operative procedures - main OPCS4	H02.9	Unspecified other excision of appendix
41200	Operative procedures - main OPCS4	H03	Other operations on appendix
41200	Operative procedures - main OPCS4	H03.1	Drainage of abscess of appendix
41200	Operative procedures - main OPCS4	H03.2	Drainage of appendix NEC
41210	Operative procedures - secondary OPCS4	H01	H01
41210	Operative procedures - secondary OPCS4	H01.1	H01.1
41210	Operative procedures - secondary OPCS4	H01.2	H01.2
41210	Operative procedures - secondary OPCS4	H01.8	H01.8
41210	Operative procedures - secondary OPCS4	H01.9	H01.9
41210	Operative procedures - secondary OPCS4	H02	H02
41210	Operative procedures - secondary OPCS4	H02.1	H02.1
41210	Operative procedures - secondary OPCS4	H02.2	H02.2
41210	Operative procedures - secondary OPCS4	H02.3	H02.3
41210	Operative procedures - secondary OPCS4	H02.8	H02.8
41210	Operative procedures - secondary OPCS4	H02.9	H02.9
41210	Operative procedures - secondary OPCS4	H03	H03
41210	Operative procedures - secondary OPCS4	H03.1	H03.1
41210	Operative procedures - secondary OPCS4	H03.2	H03.2
40001	Underlying (primary) cause of death: ICD10	K35	Acute appendicitis
40001	Underlying (primary) cause of death: ICD10	K36	Other appendicitis
40001	Underlying (primary) cause of death: ICD10	K37	Unspecified appendicitis
40002	Contributory (secondary) causes of death: ICD10	K35	Acute appendicitis
40002	Contributory (secondary) causes of death: ICD10	K36	Other appendicitis
40002	Contributory (secondary) causes of death: ICD10	K37	Unspecified appendicitis
42040	GP clinical event records	14C2.00	H/O: appendicitis
42040	GP clinical event records	25J6.00	Appendix mass
42040	GP clinical event records	7700000.0	Emergency excision of abnormal appendix and drainage HFQ
42040	GP clinical event records	7700100.0	Emergency excision of abnormal appendix NEC
42040	GP clinical event records	7700300.0	Emergency appendicectomy NEC
42040	GP clinical event records	7700400.0	Endoscopic emergency appendicectomy
42040	GP clinical event records	7700.00	Emergency excision of appendix
42040	GP clinical event records	7700.11	Emergency appendicectomy
42040	GP clinical event records	7700y00	Other specified emergency excision of appendix
42040	GP clinical event records	7700z00	Emergency excision of appendix NOS
42040	GP clinical event records	7701000.0	Interval appendicectomy
42040	GP clinical event records	7701300.0	Planned delayed appendicectomy NEC
42040	GP clinical event records	7701400.0	Endoscopic appendicectomy NEC
42040	GP clinical event records	7701.00	Other excision of appendix
42040	GP clinical event records	7701.11	Non emergency appendicectomy
42040	GP clinical event records	7701y00	Other specified other excision of appendix
42040	GP clinical event records	7701z00	Other excision of appendix NOS
42040	GP clinical event records	7701z11	Appendicectomy NEC
42040	GP clinical event records	7702000.0	Drainage of abscess of appendix
42040	GP clinical event records	7702100.0	Drainage of appendix NEC
42040	GP clinical event records	J200.00	Acute appendicitis with peritonitis
42040	GP clinical event records	J201.00	Acute appendicitis with appendix abscess
42040	GP clinical event records	J201.11	Abscess of appendix
42040	GP clinical event records	J201.12	Appendix abscess
42040	GP clinical event records	J202.00	Acute appendicitis without peritonitis
42040	GP clinical event records	J203.00	Acute appendicitis with generalised peritonitis
42040	GP clinical event records	J204.00	Acute appendicitis with localised peritonitis
42040	GP clinical event records	J20..00	Acute appendicitis
42040	GP clinical event records	J20z100	Acute gangrenous appendicitis
42040	GP clinical event records	J20z.00	Acute appendicitis NOS
42040	GP clinical event records	J21..00	Appendicitis, unqualified
42040	GP clinical event records	J220.00	Subacute appendicitis
42040	GP clinical event records	J221.00	Chronic appendicitis
42040	GP clinical event records	J222.00	Relapsing appendicitis
42040	GP clinical event records	J223.00	Recurrent appendicitis
42040	GP clinical event records	J22..00	Other appendicitis
42040	GP clinical event records	J22z.00	Other appendicitis NOS
42040	GP clinical event records	Jyu2000	[X]Other appendicitis
42040	GP clinical event records	XaYaL	Acute appendicitis with generalised peritonitis
42040	GP clinical event records	X304O	Appendix mass
42040	GP clinical event records	XE0aV	Acute appendicitis with appendix abscess
42040	GP clinical event records	XE0D8	Other excision of appendix NOS
42040	GP clinical event records	XaYaN	Acute appendicitis with localised peritonitis