Patient preferences in the treatment of diabetic retinopathy

Figures & data

Table 1 Base case estimates for diabetic retinopathy treatments

Attribute	Selective VEGF inhibitor	Focal laser	Panretinal laser	Steroid
Number of physician visits to receive treatment over a one-year period^a	9 visits	2 visits	6 visits	2 visits
Administration of eye treatment	One injection of medicine into eye	Laser procedure, in which 40–60 spots are placed on a small area of the central retina	Laser procedure, in which approximately 500 spots are placed across the retina	One injection of medicine into eye
Treatment-related pain	Mild pain at the time of treatment	Mild pain at the time of treatment	Moderate pain at the time of treatment, and some pain after treatment lasting for a day	Mild pain at the time of treatment
Benefit observed from subsequent treatments^b	After treatment wears off, same benefit is observed with each subsequent treatment	After treatment wears off, treatment benefit decreases with each subsequent treatment	After treatment wears off, treatment benefit decreases with each subsequent treatment	After treatment wears off, treatment benefit decreases with each subsequent treatment
% chance of improving central vision, in which you can read two more lines of letters on a vision chart	30%	20%	33%	40%
% chance of having blurry or blank patches in central field of vision	0%	20%	0%	0%
% chance of having blurry or blank patches in your side vision, which may result in difficulty noticing objects off to the side and seeing in dim light	0%	0%	33%	0%
% chance of needing treatment daily drops for glaucoma, which is increased eye pressure	0%	0%	0%	35%
% chance of needing surgery for glaucoma (increased eye pressure) in an operating room	0%	0%	0%	2%
% chance of having misty vision and/or glare from lights because of cataract formation	0%	0%	0%	40%
% chance of having heart attack or stroke which does not result in death	1%	0%	0%	0%

Note:

a Improvement in central vision after repeated treatments;

a number of visits specifically to receive diabetic retinopathy treatment, not routine follow-ups or monitoring for side effects.

Abbreviation: VEGF, vascular endothelial growth factor.

Table 2 Relative importance of attributes in influencing patient preferences

Attribute	Most favorable level	Least favorable level	Relative importance (% ± SEM)^a
Chance of cataract formation	0%	54%	12.8 ± 0.03
Chance of improving vision	55%	15%	12.3 ± 0.06
Chance of blurry/blank patches, side	0%	47%	11.5 ± 0.03
Chance of blurry/blank patches, central	0%	20%	10.9 ± 0.02
Benefit observed from subsequent treatments	After treatment wears off, same benefit is observed with each subsequent treatment	After treatment wears off, treatment benefit decreases with each subsequent treatment	9.6 ± 0.03
Chance of needing daily drops for glaucoma	0%	50%	9.6 ± 0.03
Chance of cardiovascular event	0%	3%	9.3 ± 0.03
Chance of needing surgery for glaucoma	0%	5%	8.6 ± 0.03
Number of physician visits	1 visit	9 visits	6.1 ± 0.03
Treatment-related pain	Mild pain at the time of treatment	Moderate pain at the time of treatment, and some pain after treatment lasting for a day	5.5 ± 0.03
Mode of administration	Laser procedure, in which 40–60 spots are placed on a small area of the central retina	Laser procedure, in which approximately 500 spots are placed across the retina	3.8 ± 0.03

Note:

a Ratio data (10% is twice as important than 5%).

Abbreviation: SEM standard error of the mean.

Table 3 Estimated percentages of patients preferring each diabetic retinopathy treatment given utilities of base case attributes

DR treatment	Overall (n = 161) % (SEM)	Treatment-naïve (n = 41) % (SEM)	Laser experience (n = 79) % (SEM)	Injection experience (n = 5) % (SEM)	Experience with both therapies (n = 36) % (SEM)
Anti-VEGF	52% (1.7)	49% (3.8)	51% (2.2)	56% (8.5)	57% (3.3)
Steroid	20% (1.2)	21% (2.4)	18% (1.4)	15% (2.8)	26% (3.0)
Focal laser	17% (1.1)	19% (2.4)	19% (1.7)	16% (7.8)	10% (1.3)
Panretinal laser	11% (0.8)	11% (1.6)	12% (1.2)	13% (1.9)	7% (1.4)

Abbreviations: DR, diabetic retinopathy; VEGR, vascular endothelial growth factor; SEM, standard error of the mean.

Table 4 Estimated percentages of patients preferring each diabetic retinopathy treatment given utilities of base case attributes by diabetic macular edema/proliferative diabetic retinopathy status

DR treatment	Neither DME nor PDR (n = 29) % (SEM)	DME only (n = 50) % (SEM)	PDR only (n = 40) % (SEM)	Both DME and PDR (n = 42) % (SEM)
Anti-VEGF	51% (3.6)	56% (2.8)	46% (3.7)	54% (3.1)
Steroid	21% (2.4)	14% (1.3)	27% (2.9)	21% (1.9)
Focal laser	17% (2.9)	19% (2.1)	17% (2.5)	15% (1.8)
Panretinal laser	11% (1.7)	12% (1.3)	10% (1.8)	11% (1.6)

Abbreviations: VEGF, vascular endothelial growth factor; DME, diabetic macular edema; DR, diabetic retinopathy; PDR, proliferative diabetic retinopathy; SEM, standard error of the mean.

Table 5 Sensitivity analyses: Percentages preferring each diabetic retinopathy treatment given improvements in base case attribute levels*

Attribute improvements	Preferring anti-VEGF (%)	Preferring steroid (%)	Preferring focal laser (%)	Preferring panretinal laser (%)
Improvements to steroid treatment:
• Cataracts (40% to 0%)	25%	59%	9%	7%
• Benefit (benefit decreases to same benefit with subsequent treatment)
Improvements to focal laser:
• Blurry/blank patches, central (20% to 0%)	31%	12%	51%	6%
• Benefit (benefit decreases to same benefit with subsequent treatment)
Improvements to panretinal laser:
• Benefit (benefit decreases to same benefit with subsequent treatment)	35%	14%	10%	41%
• Blurry/blank patches, peripheral (33% to 0%)

Note:

* Table presents all attributes that are needed to improve in order for the respective treatment to be more preferred than anti-VEGF.

Abbreviation: VEGF, vascular endothelial growth factor.