Table 4.

Number, Rate, and Adjusted Rate Ratio of Primary and Secondary Care Contacts for Patients with Prurigo Nodularis Compared with Those for Controls in the Clinical Practice Research Datalink, 2008–2018

Healthcare Sector	Prurigo Nodularis		Controls		Incidence Rate Ratio1
	Contacts	Rate ppy	Contacts	Rate ppy	Rate Ratio	95% CI	P-Value
Main analysis
Patients	2,409		2,409
All contacts
Primary care contacts, n (rate ppy)	150,140	14.77	90,981	8.94	1.48	1.47–1.49	<0.0001
Inpatient contacts, n (rate ppy)	13,235	1.30	4,677	0.46	1.80	1.75–1.85	<0.0001
Outpatient contacts, n (rate ppy)	77,683	7.64	30,956	3.04	2.15	2.13–2.18	<0.0001
Accident and emergency contacts, n (rate ppy)	6,431	0.63	3,539	0.35	1.32	1.27–1.36	<0.0001
Prurigo related contacts
Primary care contacts, n (rate ppy)	6,752	0.66
Inpatient contacts with primary diagnosis, n (rate ppy)	324	0.03
Inpatient contacts with any diagnosis, n (rate ppy)	653	0.06
Dermatology outpatient contacts, n (rate ppy)	26,025	2.56
Sensitivity analysis
Patients
All contacts	5,441		5,441
Primary care contacts, n (rate ppy)	299,115	13.61	192,598	8.62	1.43	1.42–1.44	<0.0001
Inpatient contacts, n (rate ppy)	25,560	1.16	10,184	0.46	1.72	1.68–1.75	<0.0001
Outpatient contacts, n (rate ppy)	143,004	6.51	66,084	2.96	1.90	1.88–1.92	<0.0001
Accident and emergency contacts, n (rate ppy)	12,679	0.58	7,600	0.34	1.28	1.25–1.31)	<0.0001
Prurigo related contacts
Primary care contacts, n (rate ppy)	8,551	0.39
Inpatient contacts with primary diagnosis, n (rate ppy)	429	0.02
Inpatient contacts with any diagnosis, n (rate ppy)	761	0.03
Dermatology outpatient contacts, n (rate ppy)	37,298	1.70

Abbreviations: CHD, coronary health disease; CI, confidence interval; CKD, chronic kidney disease; ppy, per patent year; T2DM, type 2 diabetes mellitus.

¹Adjusted for age at index, gender, baseline CHD, baseline T2DM, baseline CKD, and baseline depression.