Patients’ and rheumatologists’ preferences for the attributes of biological agents used in the treatment of rheumatic diseases in Spain

Figures & data

Table 1 Attributes and levels included in the scenarios

Attribute	Level
Administration method	• Subcutaneous self-administration at home
	• Intravenous administration by a health care professional at hospital
Risk of adverse events	• High risk of adverse events
	• Low risk of adverse events
Pain relief and improvement in functional capacity	• Pain relief and improvement in functional capacity
	• No pain relief and no improvement in functional capacity
Duration of effect (time until perceiving the need for a new dose)	• 1 week
	• 2 weeks
	• 4 weeks
	• 8 weeks

Table 2 Patient sociodemographic and clinical variables

Patient variables	Total (488)	RA (165)	AS (158)	PsA (165)	P-value
Age (years), mean (SD)	50.61 (12.06)	55.9 (11.5)	46.3 (11.4)	49.5 (11.4)	<0.001
Sex					<0.001
Male (%)	50.9	26.2	71.8	55.8
Female (%)	49.1	73.8	28.2	44.2
	MD 0.6%	MD 0.6%	MD 1.3%	MD 0
Marital status					0.016
Married (%)	70.1	72.1	63.3	74.5
Single (%)	14.8	10.3	22.8	11.5
Cohabiting (%)	6.4	5.4	7.6	6.1
Separated/divorced (%)	4.9	5.4	5.1	4.3
Widowed (%)	3.9	6.7	1.2	3.6
Place of residence					0.136
Living at own home (%)	92.2	95.7	87.9	92.7
Living at parents’ home (%)	5.8	2.4	9.6	5.5
Living at home of others (%)	1.9	1.8	1.9	1.8
	MD 0.4%	MD 0.6%	MD 0.6%	MD 0
Level of studies					0.413
Primary (%)	35.2	39.4	29.1	36.9
Secondary (%)	24.8	18.8	20.2	15.2
Other (%)	40	42.2	50.7	47.9
Employment status					<0.001
Employed (%)	38.6	25.9	45.8	44.2
Sick leave due to RD (%)	13	16.6	11.6	10.9
Retired (%)	16.4	25.9	6.5	16.4
Other (%)	32	32.7	36.6	28.5
Other variables
Regular alcohol consumption (%)	16	11.7	22.1	14.6	0.034
	MD 1.4%	MD 1.2%	MD 2.5%	MD 0.6%
Nonsmokers (%)	49.1	53.0	47.5	46.7	0.098
Weight (kg), mean (SD)	75.8 (15.4)	71.1 (14.9)	77.6 (15.3)	78.6 (15)	<0.001
	MD 0.8%	MD 1.2%	MD 0	MD 1.2%
Height (cm), mean (SD)	166.5 (9.3)	162.7 (8.7)	169.3 (8.9)	167.4 (9)	<0.001
	MD 0.8%	MD 1.2%	MD 0	MD 1.2%
BMI (kg/m^2), mean (SD)	27.3 (4.8)	26.8 (5)	27 (4.6)	28 (4.9)	0.058
	MD 0.8%	MD 1.2%	MD 0	MD 1.2%
Charlson index, median (SD)	0.4 (0.7)	0.5 (0.8)	0.2 (0.6)	0.3 (0.7)	<0.001
	MD 0.4%	MD 0.6%	MD 0	MD 0.6%
Time since first symptoms, mean (SD)	15 (9.6)	14.1 (8.5)	17.4 (11.2)	13.6 (8.5)	0.005
Time since diagnosis (years), mean (SD)	12.6 (8.2)	13 (7.8)	13.1 (9.2)	12.6 (8.2)	0.142
Disabling symptoms
None	29.1%	25.5%	30.4%	31.5%	0.437
Joint rigidity	30.9%	25.5%	8.2%	18.2%	0.759
Joint swelling	17.4%	30.9%	32.9%	29.1%	<0.001
Joint pain	51.8%	58.8%	43.7%	52.7%	0.055
	MD 0.2%
Limitation of functional capacity	34%	37.6%	39.2%	25.5%	0.016
Others	4.3%	3.6%	7.6%	1.8%	0.033
Complications associated with RD
Without complications	68.9%	22.7%	20.9%	25.2%	0.132
Amyloidosis	0.4%	0	0.2%	0.2%	0.598
Anemia	2.7%	1.8%	0.4%	0.4%	0.05
	MD 0.2%
Cardiac complications	1.4%	1%	0	0.4%	0.07
Intestinal complications	3.5%	0.6%	2.3%	0.6%	0.015
Ocular complications	10%	2.9%	5.9%	1.2%	<0.001
Renal complications	1.2%	0.4%	0.4%	0.4%	0.999
Pulmonary complications	2.7%	2.3%	0.2%	0.2%	0.001
Neurological complications	0.8%	0.2%	0.4%	0.2%	0.751
Others	9.8%	3.7%	2.0%	4.1%	0.185
Comorbid conditions
Without comorbidities	43.9%	12.7%	16.2%	15%	0.078
	MD 0.2%
Infectious and parasitic	2%	1%	0.4%	0.6%	0.519
	MD 0.2%
Neoplasia	0.8%	0.8%	0	0	0.043
	MD 0.4%
Endocrine, nutritional and metabolic	22.7%	10.5%	4.7%	7.6%	0.002
	MD 0.2%
Blood and hematopoietic organs	1.6%	0.2%	0.6%	0.8%	0.406
	MD 0.2%
Mental disorders	1.6%	0.2%	0.8%	0.6%	0.386
	MD 0.2%
Nervous system and sense organs	1.8%	1%	0.6%	0.2%	0.33
	MD 0.4%
Circulatory system	12.7%	5.9%	2.9%	3.9%	0.055
	MD 0.2%
Respiratory system	4.1%	1.4%	1.4%	1.2%	0.935
	MD 0.2%
Digestive system	7%	1.6%	3.3%	2%	0.153
	MD 0.2%
Genitourinary system	4.1%	1.2%	1%	1.8%	0.537
	MD 0.2%
Skin and subcutaneous tissue	3.5%	0.4%	1.2%	1.8%	0.104
	MD 0.2%
Osteomyoarticular system and connective tissue	6.4%	3.1%	1.2%	2%	0.148
	MD 0.2%
Congenital anomalies	0.2%	0.2%	0	0	0.376
	MD 0.2%
Others	8.8%	2.3%	2.3%	4.3%	0.09
	MD 0.4%

Note: Percentages calculated on data available.

Abbreviations: MD, missing data; BMI, body mass index; RA, rheumatoid arthritis; AS, ankylosing spondylitis; PsA, psoriatic arthritis; SD, standard deviation; RD, rheumatic disease.

Table 3 Number and percentage of patients receiving treatment with BAs at the time of study inclusion, and previous treatment

	Actual treatment with BAs				Previous treatment with BAs
	Total, %	RA	AS	PsA	Total, %	RA	AS	PsA
Etanercept	133	23.6%	20.9%	37%	44	12.7%	6.3%	7.9%
	27.3%				9%
Adalimumab	128	21.2%	27.2%	30.3%	52	14.5%	12%	5.5%
	27.3%				10.7%
Infliximab	113	9.7%	36.7%	23.6%	46	8.5%	10.1%	9.7%
	23.2%				9.4%
Golimumab	37	2.4%	13.3%	7.3%	13	3%	1.9%	3%
	7.6%				2.7%
Tocilizumab	25	15.2%	0	0	4	2.4%	0	0
	5.1%				0.8%
Abatacept	24	12.1%	0.6%	1.8%	2	1.2%	0	0
	4.9%				0.4%
Rituximab	12	7.3%	0	0	4	2.4%	0	0
	2.5%				0.8%
Certolizumab pegol	9	5.5%	0	0	2	1.2%	0	0
	1.8%				0.4%
Ustekinumab	1	0	0	0.6%	0	0	0	0
	0.2%

Abbreviations: BAs, biological agents; RA, rheumatoid arthritis; AS, ankylosing spondylitis; PsA, psoriatic arthritis.

Figure 1 Patients’ (A) and rheumatologists’ (B) utility values.

Note: Estimated utility values for each attribute in the sample of patients and rheumatologists.
Abbreviation: AEs, adverse events.

Figure 2 Relative importance values given by both patients and rheumatologists to the attributes of biological agents and for specific rheumatic conditions.

Abbreviations: RA, rheumatoid arthritis; AS, ankylosing spondylitis; PsA, psoriatic arthritis.

Figure 3 Pareto diagrams representing patients’ and professionals’ utility values for subcutaneous and intravenous treatment alternatives.

Notes: (A) Utility values for patients regarding subcutaneous treatment. (B) Utility values for patients regarding intravenous treatment. (C) Utility values for professionals regarding subcutaneous treatment. (D) Utility values for professionals regarding intravenous treatment. Duration of effect indicates the time until perceiving the need for a new dose (1 week, 4 weeks, and 8 weeks).
Abbreviations: AEs, adverse events; BA, biological agent.

Table 4 Factors influencing patients’ and rheumatologists’ preferencesa

Factors	Estimated coefficient	P-value
Patients
Administration method
Age	−5.72	0.0012
Sex (female vs male)	−10.45	0.0142
Intestinal complications (yes vs no)b	−11.05	0.024
Smoking habits: nonsmoker <1 year (vs smoker)	−0.61	0.8162
Smoking habits: nonsmoker >1 year (vs smoker)	1.12	0.6246
Smoking habits: never-smoker (vs smoker)	0.16	0.1019
Joint swelling (yes vs no)	4.27	0.0939
Joint rigidity (yes vs no)	−3.21	0.1185
Complications associated with RD (yes vs no)b	2.01	0.1111
Cardiac complications (yes vs no)b	−3.65	0.0619
Renal complications (yes vs no)b	−18.66	0.0227
Pulmonary complications (yes vs no)b	−11.21	0.0064
Neurological complications (yes vs no)b	9.4	0.0443
Genitourinary comorbidities not associated with RD (yes vs no)b	0.12	0.1221
Skin comorbidities not associated with RD (yes vs no)b	−2.86	0.1418
Risk of side effects
Sex (female vs male)	5.08	0.0013
Pathology (AS vs RA)	4.12	0.0367
Joint rigidity (yes vs no)	4.48	0.0057
Limitation of functional capacity (yes vs no)	−5.42	0.0008
Intestinal complications (yes vs no)b	10.45	0.0083
Ocular complications (yes vs no)b	−5.55	0.0255
Genitourinary comorbidities (yes vs no)b	7.74	0.0237
BMI	−0.28	0.0666
Pathology (PsA vs RA)	1.58	0.3854
Pulmonary complications (yes vs no)b	8.42	0.0738
Osteomyoarticular comorbidities (yes vs no)b	−4.38	0.1352
Relief of pain
Joint swelling (yes vs no)	−2.96	0.0283
Limitation of functional capacity (yes vs no)	6.76	0.0011
Age	−1.49	0.5293
Pathology (AS vs no AS)	4.28	0.0616
Pathology (PsA vs no PsA)	−6.72	0.0134
Renal complications (yes vs no)b	12.33	0.1574
Blood complications (yes vs no)b	10.15	0.1423
Skin complications (yes vs no)b	11.94	0.0852
Duration of effect
Sex (female)	2.37	0.0836
BMI	0.22	0.1273
Regular alcohol consumption (no vs yes)	−3.17	0.084
Symptom duration	−0.13	0.0581
Endocrine comorbidities (yes vs no)b	−2.3	0.1521
Circulatory comorbidities (yes vs no)b	3.63	0.0828
Congenital anomalies/comorbidities (yes vs no)b	−22.11	0.1096
Rheumatologists
Administration method	NA	NA
Risk of side effects
Age	−1.31	0.0007
Duration of professional exercise	1.03	0.0099
Relief of pain
Sex (female vs male)	−6.39	0.0329
Age	0.3	0.0662
Time until perceiving the need for a new dose
Age	0.59	0.0396
Sex (female vs male)	3.88	0.0256
Duration of professional practice	−0.61	0.04

Notes:

a Results from multivariate regression analysis;

b according to physician’s judgment. The coefficients of the quantitative variables indicate the magnitude of change in the independent variable for each unit of increase in the dependent variable. In the qualitative variables, coefficients indicate the change in the variable response with respect to the reference category (positive values indicate increase; negative values indicate decrease).

Abbreviations: BMI, body mass index; RA, rheumatoid arthritis; AS, ankylosing spondylitis; PsA, psoriatic arthritis; RD, rheumatic disease; NA, not applicable.