A successful linkage of a named patient products of sublingual immunotherapy-dispensing registry to French healthcare insurance database (SNDS): methodological constitution of the EfficAPSI cohort

Figures & data

Figure 1. Presentation of databases and linkage.

Figure 2. Study design.

SLIT: SubLingual Immuno Therapy, AIT: Allergen Immuno Therapy, AH: AntiHistamine, INCS: IntraNasal CorticoSTEROID, ICS: Inhaled CorticoSteroid, LABA: Long-Acting Beta Agonist, SABA: Short-Acting Beta Agonist, COPD: Chronic Obstructive Pulmonary Disease, GERD: GastroEsophageal Reflux Disease, HCRU: Health Care Resource Utilization.

Table 1. Available variables extracted from both databases.

	Stallergenes Greer	SNDS
Demographic data	Not available	Age, sex, individual complementary universal insurance – CMUc, department of residence
Hospitalizations in public and private hospitals	Not available	Dates of hospitalizations, primary, related, and associated diagnoses coded using ICD-10, medical procedures, costly drugs on top of Diagnostic-Related Groups (DRG)
LTD	Not available	List of 30 LTD, coded using ICD-10, with start and end date of registration
Outpatient medical expenses	Not available	Consultation dates and specialty of physician, date, and nature of paramedical care (nurse, physiotherapist), date and type of medical procedures
Outpatient drugs	For SLIT liquid, dates of dispensation, number of vials and allergen composition of vials	Dates of dispensation, drugs coded using ATC and a unique national registration code (CIP) which inform on dosage and pack, number of packs dispensed, prescriber
Sick leave	Not available	Number of paid sick leave days

CMUc: couverture maladie universelle complémentaire; ICD-10: international classification of diseases-10^th revision; DRG: diagnostic-related groups; LTD: long-term disease; ATC: anatomical therapeutic chemical; CIP: code identifiant de présentation.

Figure 3. Flow-chart of the selection of the population.

Table 2. Description of the population at baseline, before weighting.

Characteristics, n (%)	Exposed, n = 112,492	Controls, n = 333,082	p
Age at index date, years			<0.001
Mean (SD)	37.8 (10.3)	38.8 (20.9)
[5–25]	11,435 (10.2)	92,837 (27.9)
[25–40]	53,349 (47.4)	76,904 (23.1)
[40–50]	34,417 (30.6)	55,863 (16.8)
≥50	13,291 (11.8)	107,478 (32.3)
Sex			<0.001
Male	49,450 (44.0)	132,845 (39.9)
Female	63,042 (56.0)	200,237 (60.1)
CMUc	5,930 (5.3)	44,324 (13.3)	<0.001
Comorbidities
Mild-to-moderate asthma	34,595 (30.8)	97,535 (29.3)	<0.001
Anxiety	7,521 (6.7)	47,317 (14.2)	<0.001
Depression	7,792 (6.9)	36,743 (11.0)	<0.001
Morbid obesity	899 (0.8)	5,058 (1.5)	<0.001
Nasal polyposis	24 (0.0)	126 (0.0)	0.006
Gastroesophageal reflux disease	9,256 (8.2)	56,890 (17.1)	<0.001
Sinusitis	293 (0.3)	848 (0.3)	0.737
AR treatment dispensation during the 2 years preceding the index date, mean (SD)
AH	3.9 (4.7)	5.2 (6.4)	<0.001
INCS	2.3 (2.9)	3.6 (4.4)	<0.001
AH and INCS co-dispensation	1.5 (2.3)	1.7 (3.5)	<0.001
Death	354 (0.3)	8,150 (2.4)	<0.001

SD: standard deviation; CMUc: couverture maladie universelle complémentaire; AR: allergic rhinitis; AH: antihistamine; INCS: intranasal corticosteroid.

Data availability statement

According to the principles of data protection and French regulations, the authors cannot publicly release the data from the ‘Système National des Données de Santé’ (SNDS). However, any person or structure, public or private, for-profit or nonprofit can access SNDS data upon authorization from the ‘Commission Nationale de l’Informatique et des Libertés’ (i.e., the French Data Protection Office) to carry out a study, research, or an evaluation of public interest (https://www.snds.gouv.fr).