Data from: Computer-aided X-ray screening for tuberculosis and HIV testing among adults with cough in Malawi (the PROSPECT study): a randomized trial and cost-effectiveness analysis

Suboptimal tuberculosis (TB) diagnostics and HIV contribute to the high
global burden of TB. We investigated costs and yield from systematic
HIV-TB screening, including computer-aided digital chest X-ray (DCXR-CAD).
Suboptimal tuberculosis (TB) diagnostics and HIV contribute to the high
global burden of TB. We investigated costs and yield from systematic
HIV-TB screening, including computer-aided digital chest X-ray (DCXR-CAD).
In this open, three-arm randomised trial, adults (≥18 years) with cough
attending acute primary services in Malawi were randomised (1:1:1) to
standard-of-care (SOC); oral HIV testing (HIV screening) and linkage to
care; or HIV testing and linkage to care plus DCXR-CAD with sputum Xpert
for high CAD4TBv5 scores (HIV-TB screening). Participants and study staff
were not blinded to intervention allocation, but investigator blinding was
maintained until final analysis. The primary outcome was time to TB
treatment. Secondary outcomes included proportion with same-day TB
treatment; prevalence of undiagnosed/untreated bacteriologically-confirmed
TB on day 56; and undiagnosed/untreated HIV. Analysis was done on an
intention to treat basis. Cost-effectiveness analysis used a
health-provider perspective. Between 15/11/2018-27/11/2019, 8236 were
screened for eligibility, with 473, 492, and 497 randomly allocated to
SOC, HIV, and HIV-TB screening arms; 53 (11%), 52 (9%), and 47 (9%) were
lost to follow-up, respectively. At 56 days, TB treatment had been started
in 5 (1.1%) SOC, 8 (1.6%) HIV-screening, and 15 (3.0%) HIV-TB screening
participants. Median (IQR) time to TB treatment was 11 (6.5-38), 6 (1-22)
and 1 (0-3) days (hazard ratio for HIV-TB vs. SOC: 2.86, 1.04-7.87), with
same-day treatment of 0/5 (0%) SOC, 1/8 (12.5%) HIV, and 6/15 (40.0%)
HIV-TB screening arm TB patients (p=0.03). At day 56, 2 SOC (0.5%), 4 HIV
(1.0%), and 2 HIV-TB (0.5%) participants had undiagnosed
microbiologically-confirmed TB. HIV screening reduced the proportion with
undiagnosed or untreated HIV from 10 (2.7%) in the SOC arm to 2 (0.5%) in
the HIV-screening arm (risk ratio [RR]: 0.18, 0.04-0.83), and 1 (0.2%) in
the HIV-TB screening arm (RR: 0.09, 0.01-0.71). Incremental costs were
US$3.58 and US$19.92 per participant screened for HIV and HIV-TB; the
probability of cost-effectiveness at a US$1200/quality-adjusted life-year
(QALY) threshold were 83.9% and 0%. Main limitations were the lower than
anticipated prevalence of tuberculosis and short participant follow-up
period; cost and quality of life benefits of this screening approach may
accrue over a longer time horizon. DCXR-CAD with universal HIV screening
significantly increased the timeliness and completeness of HIV and TB
diagnosis. If implemented at scale this has potential to rapidly and
efficiently improve TB and HIV diagnosis and treatment.