Long-term health economic benefits of sensor-augmented pump therapy vs continuous subcutaneous insulin infusion alone in type 1 diabetes: a UK perspective

Figures & data

Table 1. Baseline cohort characteristics and treatment effects.

Parameter	Value
Mean age, years	27
Male, %	48.5
HbA1c, % (mmol/mol)	10 (86)
Duration of diabetes, years	13
Treatment effect, reduction in HbA1c, %
SAP + LGS	−1.49
CSII	−0.62

CSII, continuous subcutaneous insulin infusion; HbA_1c, glycated hemoglobin; SAP, sensor-augmented pump therapy.

Table 2. Summary of base-case results.

	SAP + LGS	CSII alone	Difference
Life expectancy, years	23.79	21.91	1.88
Undiscounted life expectancy, years	30.86	27.83	3.03
Quality-adjusted life expectancy, QALYs	17.88	14.89	2.99
Total direct costs, GBP	125,559	88,991	36,568
Treatment costs, GBP	59,561	14,238	45,323
Cardiovascular complication costs, GBP	4674	4346	328
Renal complication costs, GBP	8270	11,536	−3266
Ulcer/amputation/neuropathy costs, GBP	33,505	38,456	−4951
Ophthalmic complication costs, GBP	17,793	17,285	508
ICER (95% CI), GBP per QALY gained	12,233 (12,225–12,351)

CI, confidence interval; CSII, continuous subcutaneous insulin infusion; ICER, incremental cost-effectiveness ratio; QALY, quality-adjusted life year; SAP, sensor-augmented pump therapy; LGS, low glucose suspend.

All costs are presented in 2013 GBP.

Table 3. Delay in onset of diabetes-related complications with SAP + LGS vs CSII alone.

	Time alive and free of complication, years
	SAP + LGS	CSII alone	Difference
Microalbuminuria	11.6	9.1	2.5
Gross proteinuria	26.7	22.9	3.8
End-stage renal disease	30.2	27.0	3.2
First ulcer	22.7	19.1	3.6
Amputation	28.3	25.1	3.2
Neuropathy	14.6	11.2	3.4
Peripheral vascular disease	29.4	26.5	2.9
Congestive heart failure	29.5	26.6	3.0
Angina	29.2	26.3	2.8
Myocardial infarction	29.7	26.8	2.9
Stroke	29.3	26.7	2.7
Cataract	27.0	24.6	2.4
Macular edema	19.0	16.8	2.2
Severe vision loss	23.2	20.8	2.3
Proliferative retinopathy	26.0	22.5	3.5

CSII, continuous subcutaneous insulin infusion; SAP, sensor-augmented pump therapy; LGS, low glucose suspend.

Table 4. Summary findings of sensitivity analyses.

Scenario	Quality-adjusted life expectancy, QALYs			Costs, GBP			ICER, GBP per QALY gained
	SAP  + LGS	CSII	Difference	SAP  + LGS	CSII	Difference
Base case	17.86	14.87	2.99	125,559	88,991	36,568	12,233
Societal perspective	17.86	14.87	2.99	250,651	240,609	10,042	3359
No FoH utility (base case 0.0552 benefit for SAP)	16.56	14.87	1.68	125,559	88,991	36,568	21,816
No severe hypoglycemia benefit	17.81	15.03	2.73	125,513	87,831	37,682	13,818
No FoH utility and no severe hypoglycemia benefit	16.50	15.08	1.42	125,513	87,831	37,682	26,600
Baseline HbA1c 9.0% (75 mmol/mol) (base case 10%)	18.91	16.08	2.83	122,536	83,387	39,149	13,839
Baseline HbA1c 8.1% (65 mmol/mol) (base case 10%)	19.81	17.12	2.69	119,690	78,348	41,342	15,392
Discount rates 3.5% per annum costs and outcomes (base case 3.5% for costs and 1.5% for clinical outcomes)	13.43	11.44	1.99	125,559	88,991	36,568	18,371

CSII, continuous subcutaneous insulin infusion; ICER, incremental cost-effectiveness ratio; FoH, fear of hypoglycemia; QALY, quality-adjusted life year; SAP, sensor augmented pump therapy; SMBG, self-monitoring of blood glucose; LGS, low glucose suspend.

Figure 1. Cost-effectiveness acceptability curve for SAP + LGS vs CSII. CSII, continuous subcutaneous insulin infusion; QALY, quality-adjusted life year; SAP, sensor-augmented pump.