Costs of medication use among patients with juvenile idiopathic arthritis in the Dutch healthcare system

Figures & data

Table 1. Characteristics of patients included in the analysis, reported separately for all patients and for patients who received a biological during the period of follow-up in this study

	All patients	Users of biologicals during this study
Number of patients, n (%)	691 (100.0%)	211 (30.5%)
Age at JIA diagnosis in years, median (IQR)	8.0 (4.0–12.6)	9.0 (4.6–13.5)
Duration of follow-up in years, median (IQR)	4.9 (2.8–7.0)	4.7 (2.8–6.9)
Gender, n (%)
Male	244 (35.3%)	82 (38.9%)
JIA subtype, n (%)
Oligoarticular persistent JIA	294 (42.5%)	40 (19.0%)
ANA+	147 (21.3%)	22 (10.4%)
ANA-	147 (21.3%)	18 (8.5%)
Polyarticular JIA	175 (25.3%)	73 (34.6%)
RF-	144 (20.8%)	53 (25.1%)
RF+	31 (4.5%)	20 (9.5%)
Extended oligoarticular JIA	70 (10.1%)	29 (13.7%)
Enthesitis related JIA	59 (8.5%)	23 (10.9%)
Systemic JIA	57 (8.2%)	34 (16.1%)
Psoriatic arthritis	29 (4.2%)	12 (5.7%)
Undifferentiated JIA	7 (1.0%)	0 (0.0%)

ANA = antinuclear antibody; IQR = interquartile range; JIA = juvenile idiopathic arthritis; RF = rheumatoid factor

Table 2. Heat map showing an overview of mean total annual costs of medication per patient for all JIA patients and specified per subtype

From left to right, this table describes the number of patients; the mean annual costs per patient with the percentage of costs which is attributable to each of these subgroups in this database; the minimum and maximum mean annual costs per patient; as well as an overview of mean annual costs per patient when specified according to type of medication with the percentage of costs that are attributable to each type of medication.

ANA = antinuclear antibody; DMARDs = disease-modifying anti-rheumatic drugs; JIA = juvenile idiopathic arthritis; MTX = methotrexate, RF = rheumatoid factor.

Table 3. Heat map showing an overview of mean annual total costs of biologicals per patient, among users only, for all JIA patients and specified per subtype

From left to right, this table describes the number of patients; the mean annual costs per patient; the mean annual costs per patient when specified according to type of biological, including the percentage of costs that are attributable to each type of biological and the number of patients that used each type of biological. All biologicals prescribed to fewer than 5 patients were reported as ‘<5ʹ (instead of reporting the exact number), to prevent that results can be traced back to individual patients. ANA = antinuclear antibody; CTLA-4 = cytotoxic T-lymphocyte-associated protein 4; DMARDs = disease-modifying anti-rheumatic drugs; IL = interleukin; JIA = juvenile idiopathic arthritis; MTX = methotrexate, RF = rheumatoid factor, TNFα = tumor necrosis factor alpha.

Figure 1. Distribution of mean total annual costs of JIA-related medication per patient (including biologicals, non-biological DMARDs, intra-articular injections, and steroids), regardless of JIA subtype. In this figure, 4 patients were excluded because they were out of range in this figure. These involved patients with systemic JIA or polyarticular RF+ JIA. DMARDs = disease-modifying anti-rheumatic drugs; JIA = juvenile idiopathic arthritis, RF = rheumatoid factor

Figure 2. Mean annual number of days non-biological DMARDs and steroids. This figure represents the mean annual number of days of non-biological DMARD use (divided into MTX and other DMARDs) and systemic steroids among all JIA patients during the entire follow-up period, specified per JIA subtype. ANA = antinuclear antibody; DMARDs = disease-modifying anti-rheumatic drug; Enth.r. = enthesitis-related; Ext. = extended; JIA = juvenile idiopathic arthritis; MTX = methotrexate, Oligo. = oligoarticular; Poly. = polyarticular; Psor. arthr = psoriatic arthritis; RF = rheumatoid factor; Syst. = systemic; und. = undifferentiated

Figure 3. Mean days of biological use per year among users. This figure represents the mean days of biological use per year among JIA patients who were prescribed a biological during the follow-up period n = 211), specified per subtype. The first month in which a biological was prescribed was used as starting point of the analysis for each individual patient. ANA = antinuclear antibody; CTLA-4 = cytotoxic T-lymphocyte-associated protein 4; Enth.r. = enthesitis-related; Ext. = extended; IL = interleukin; JIA = juvenile idiopathic arthritis; Oligo. = oligoarticular; Poly. = polyarticular; Psor. arthr = psoriatic arthritis; RF = rheumatoid factor; Syst. = systemic; TNF = tumor necrosis factor; und. = undifferentiated

Figure 4. Overview of mean monthly costs of JIA-related medication per patient over the course of follow-up. Each point represents the mean costs of JIA-related medication for the set of patients of which data is available during each of the 120 months. ‘0ʹ represents the moment of JIA diagnosis. ‘n’ represents the number of patients included at the different months of follow-up