High mortality risk among individuals assumed to be TB-negative can be predicted using a simple test.
OBJECTIVE
To determine mortality among assumed TB negative (aTBneg) individuals in Guinea-Bissau and to investigate whether plasma levels of soluble urokinase receptor (suPAR) can be used to determine post-consultation mortality risk.


METHODS
This prospective West-African cohort study included 1007 aTBneg individuals who were enrolled from 2004 to 2006; 4983 age-matched controls were followed for comparison. Plasma suPAR levels were measured using the suPARnostic ELISA. Survival was analysed using Cox regression, ROC curves and Kaplan-Meier analysis.


RESULTS
After 3 months of follow-up, mortality was 21 per 100 person-year-observation (PYO) among aTBneg individuals and three per 100 PYO among the control population [mortality rate ratio (MRR) = 6.92 (95% CI 4.48-10.7)]. SuPAR values ranged between 0.9 and 45 ng/ml in aTBneg individuals. A log-linear relationship was found between suPAR levels <15 ng/ml and mortality. In the log-linear range, a 1 ng/ml increase was associated with a 46% increase in the mortality rate: MRR = 1.46 (95% CI 1.34-1.59). The area under the ROC curves was 0.88 for HIV-positive individuals and 0.79 for HIV-negative individuals.


CONCLUSIONS
Our study showed a high mortality rate among aTBneg individuals and demonstrated that suPAR measurements can provide prognostic information on mortality among individuals without disease diagnosis. Measuring suPAR is a technically simple method for determining mortality risk in individuals that are assumed to be TB-negative.
Rabna
Paulo
P
Bandim Health Project, Indepth Network, Bissau, Guinea-Bissau, West Africa. p.rabna@bandim.org
Andersen
Andreas
A
Wejse
Christian
C
Oliveira
Ines
I
Gomes
Victor Francisco
VF
Haaland
Maya Bonde
MB
Aaby
Peter
P
Eugen-Olsen
Jesper
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006169:Guinea-Bissau / Q000453:epidemiology; D015658:HIV Infections / Q000276:immunology / Q000401:mortality*; D015497:HIV-1; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011933:Reagent Kits, Diagnostic; D055293:Receptors, Urokinase Plasminogen Activator / Q000097:blood*; D018570:Risk Assessment; D016019:Survival Analysis; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000401:mortality*; D055815:Young Adult
D015415:Biomarkers; D011933:Reagent Kits, Diagnostic; D055293:Receptors, Urokinase Plasminogen Activator