Table 2.
Intervention model inputs for base-case analysis and sensitivity analysis (see Supplemental Table 2 for the respective references).
| Parameter | Value | Sensitivity analysis range |
|---|---|---|
| Epidemiology | ||
| Prevalence of PA in resistant HTN | 0.20 | 0.11–0.23 |
| Proportion of unilateral PA | 0.43 | 0.35–0.60 |
| Prevalence of incidental adrenal nodules | 0.05 | 0.01–0.09 |
| Test characteristics | ||
| Sensitivity of screening testing (ARR) | 0.78 | 0.66–0.98 |
| Specificity of screening testing (ARR) | 0.83 | 0.63–0.99 |
| Sensitivity of confirmatory testing (SIT) | 0.83 | 0.55–0.90 |
| Specificity of confirmatory testing (SIT) | 0.75 | 0.75–1.00 |
| Probability of contralateral nodule CT in APA | 0.12 | 0.06–0.13 |
| Probability of true positive CT in APA (sensitivity given APA) | 0.59 | 0.49–0.62 |
| Probability of bilateral CT abnormalities in APA | 0.15 | 0.13–0.36 |
| Probability of normal CT in APA | 0.14 | 0.07–0.25 |
| Probability of bilateral CT abnormalities in BAH (sensitivity given BAH) | 0.41 | 0.19–0.46 |
| Probability of normal CT in BAH | 0.22 | 0.22–0.43 |
| Probability of unilateral CT in BAH | 0.36 | 0.33–0.38 |
| Lateralizing AVS with BAH (false-positive given true bilateral disease) | 0.02 | 0.02–0.20 |
| Sensitivity of AVS for unilateral disease (true-positive given true unilateral disease) | 0.93 | 0.80–0.93 |
| Proportion of unsuccessful adrenal vein cannulation | 0.18 | 0.04–0.37 |
| Procedural morbidity | ||
| Morbidity from AVS (bleeding) | 0.01 | 0.006–0.07 |
| Morbidity from surgery | 0.07 | 0.06–0.08 |
| Mortality from adrenalectomy | 0.01 | 0.00–0.01 |
| Treatment effects (ΔmmHg) | ||
| SBP change with death/no treatment | 0.00 | – |
| SBP change treatment of primary hypertensive patients with MRA | 10.00 | 4–22 |
| SBP change treatment PA with MRA | 20.00 | 11–33 |
| Incremental SBP change with PA adrenalectomy (over MRA) | 10.00 | 0–20 |
| Costs | ||
| Screening ARR (CPT 82088, 84244,84132) | $93 | (0.5–1.5) BCE |
| Confirmatory saline infusion testing (CPT 96365, 93666) | $141 | (0.5–1.5) × BCE |
| Abdominal CT (CPT 74170) | $329 | (0.5–1.5) BCE |
| Adrenal venous sampling (CPT 75893, 36500) | $2,645 | (0.5–1.5) × BCE |
| Adrenalectomy (surgery + anesthesia)a (CPT 60650, 00866) | $3,054 | (0.5–1.5) × BCE |
| Hospitalization (DRGb 615) | $7,867 | (0.5–1.5) × BCE |
| Hospitalization w/MCC (DRG 614) | $16,833 | (0.5–1.5) BCE |
| One year cost of spironolactone | $158 | (0.5–1.5) × BCE |
ARR – aldosterone to renin ratio; SIT – saline-infusion testing; APA – aldosterone producing adenoma; BAH – bilateral adrenal hyperplasia; MCC – major comorbidities or complications; SBP – systolic blood pressure; MRA: Mineralocorticoid-receptor antagonist; BCE – base-case estimate.
a
Cost of anesthesia was based on the product of average anesthesia time (15 minute increments), 2013 HCPCS Anesthesia Base Units, and the national anesthesia conversion factor.
b
DRG – Diagnosis-related group for adrenal procedures with and without major comorbidities or complications.