Table 3.
Summary of results of decision tree analysis of syphilis costs: Components of lifetime cost per infection
| Outcome | Percentage of infections in which outcome occurs | Discounted cost of outcome if outcome occurs | Contribution of outcome to average cost per infection |
|---|---|---|---|
| Outcomes among infections that are reported as cases | |||
| Treated for P&S or early non-P&S syphilis, no early neurosyphilis/ocular syphilis | 48.79% | $680 | $331.75 |
| Treated for P&S or early non-P&S syphilis, and early neurosyphilis/ocular syphilis | 1.61% | $8,350 | $134.67 |
| Treated for late syphilis,* no early neurosyphilis/ocular syphilis | 28.65% | $1,612 | $461.78 |
| Treated for late syphilis,* and early neurosyphilis/ocular syphilis | 0.95% | $9,282 | $87.91 |
| Outcomes among infections that are not reported as cases ** | |||
| Treated for syphilis but not reported as a case | 14.50% | $1,025 | $148.58 |
| Treated inadvertently, or unrelated death within 30 years, or both | 4.84% | $0 | $0.00 |
| Latent syphilis, no adverse outcomes, no treatment costs | 0.45% | $0 | $0.00 |
| Treated for late benign syphilis | 0.11% | $1,236 | $1.31 |
| Treated for cardiovascular syphilis | 0.06% | $14,461 | $8.59 |
| Treated for tabes dorsalis | 0.01% | $16,768 | $2.21 |
| Treated for meningovascular syphilis | 0.02% | $32,300 | $6.40 |
| Treated for general paresis | 0.01% | $54,176 | $7.15 |
| Total (all outcomes) | 100% | Not applicable | $1,190.36 |
The “treated for late syphilis” outcome also includes those treated for syphilis of unknown duration. See manuscript text and Figure 1 for a more detailed description of the outcomes.
“Infections that are not reported as cases” refers to those who are not reported as cases within 30 years as shown in the decision tree in Figure 1.
For those treated for syphilis but not reported as a case, we assumed that the proportion treated for P&S or early non-P&S syphilis would be the same as for the reported cases (e.g., the $1,025 value shown here was calculated as (0.630 x $680) + ((1 – 0.630) x $1,612), where 0.630 is the base case probability of treatment for P&S or early non-P&S syphilis among reported cases. We assumed no early symptomatic neurosyphilis and no ocular syphilis among those treated for syphilis but not reported as a case.
The discounted costs in this table have been discounted to the time of infection.
Costs are in 2019 U.S. dollars.