Table 1.

Characteristics of studies for gastroparesis (GP), organized by population setting and then first author.

Study	Data Source	Dates	Case Definition	# GP Studied	# At Risk Population	Estimates and Major Findings
Community
Jung, et al. 2009	Rochester Epidemiology Project	1996 – 2006	ICD codes, objective tests, and Sx	222	124,277	Prevalence: men and women 9.6 and 37.8 (average 24.2) per 100,000 persons; Incidence: men and women 2.5 and 9.8 (average 6.3) per 100,000 person-years, respectively¥
Syed, et al. 2020	Explorys	1999 – 2014	ICD-9 code	69,950	43,827,910	Prevalence overall 159.6 per 100,000 persons; T1D and T2D prevalence was 4.59% and 1.31%, respectively
Ye, et al. 2021 (UK)	UK Clinical Practice Research Datalink	2000 – 2016	Chart diagnosis	1,135	11,576,068	Prevalence 13.8 per 100,000 persons; incidence 1.9 per 100,000 person-years; 39.4% idiopathic, 37.5% diabetic¥
Ye, et al. 2022 (USA)	Optum Clinformatics Data Mart	2000 – 2019	ICD codes, objective tests, and Sx	71,775	82,574,650	Overall prevalence of GP 267.7 per 100,000; “definite” GP: 21.5 per 100,000 persons; female predominance; 57.4% diabetic, 15% post-surgical, 11.8% drug-induced, 11.3% idiopathic¥
Inpatient/Emergency Department
Bell, et al. 2002 §	NC Hospital Discharge Database	1998	ICD-9 code	1,476	NA	Of all GP discharges, 38.9% had diabetic GP; mortality among diabetic GP 0.6%; female predominance
Bielefeldt 2013	State Inpatient Database	2007 – 2010	ICD-9 code	NA*	NA	Fewest and greatest inpatient admissions in Utah and Maryland, respectively; mortality estimate 0.5 to 2.3 per 100,000 persons†
Hirsch, et al. 2019	National ED Sample	2006 – 2013	ICD-9 code	203,248	240 millionΩ	ED visits increased from 12.9 to 27.3 per 100,000 visits; among diabetic GP, visits increased by 148%; female predominance
Kichloo, et al. 2021		2016 – 2017	ICD-10 code	99,695	> 71 millionα	78.1% with diabetic GP; overall inpatient mortality estimate 0.25%; non-diabetic GP more common in white race
Nusrat, et al. 2013	Nationwide Inpatient Sample	1994 – 2009	ICD-9 code	129,578Δ	NA	Hospitalizations for primarily GP increased 18-fold while FGIDs decreased by half; female predominance
Wadhwa, et al. 2017		1997 – 2013	ICD-9 code	150,532Δ	NA	Discharge diagnoses overall increased 4-fold¥; female predominance; among T1D and T2D there was 6- and 3.7-fold increases, respectively
Wang, et al. 2008		1995 – 2004	ICD-9 code	60,895	361,768,699	Hospitalizations with GP as primary and secondary diagnosis increased 2.5- and 2.4-fold, respectively
Diabetes Mellitus
Aleppo, et al. 2017	T1D Exchange Registry	2010 – 2012	Chart diagnosis	340	7,107	4.8% prevalence among persons with T1D; female predominance
Choung, et al. 2012	Rochester Epidemiology Project	1996 – 2006	ICD codes, objective tests, and Sx	15	227 T1D, 360 T2D, 639 controls	Incidence of GP over 10 years: 5.2% in T1D, 1.0% in T2D, and 0.2% in controls

^§Study estimates were limited to patients with concurrent diagnosis of diabetes based on the medical record.

^*Admissions for GP ranged from 24.3 to 117.1 per 100,000 persons (normalized to state 2010 census data).

^†Estimates standardized to state populations based on 2010 census data.

^ΔNumber obtained by estimating values from graphical figures using the WebPlotDigitizer, version 4.5 (https://apps.automeris.io/wpd/), accessed April 10, 2022.

^ΩEstimated as NEDS captures about 30 million ED visits per year.

^αExact number not provided.

^¥Prevalence and incidence estimates were, at minimum, age-adjusted/standardized to the population.

ED, Emergency Department; FGID, functional gastrointestinal disorders; GP, gastroparesis; ICD, International Classification of Diseases; NA, not available; NC, North Caroline; Sx, symptoms; T1D, type 1 diabetes mellitus; T2D, type 2 diabetes mellitus; UK, United Kingdom; USA, United States of America.