Tuberculosis among people with HIV infection in the United Kingdom: opportunities for prevention?
OBJECTIVE
To investigate the incidence of, and risk factors for, tuberculosis among HIV clinic attendees in the United Kingdom.


METHODS
Observational cohort study of 27 868 individuals in the United Kingdom Collaborative HIV Cohort collaboration, 1996-2005.


RESULTS
Among individuals not taking combination antiretroviral therapy (cART), tuberculosis incidence was considerably higher among individuals of black African vs. white or other ethnicities {incidence rates 9.9 [95% confidence intervals (CIs) 7.2, 12.6], 2.5 [95% CI 1.8, 3.0] and 4.4 [95% CI 2.7, 6.0] episodes per 1000 person-years, respectively}. Tuberculosis incidence decreased with time after starting cART; among black Africans, incidence was consistently higher and remained substantial (5.3 per 1000 person-years) at 24 months and longer after starting cART. The strongest independent risk factors for tuberculosis after cART start were most recent CD4 cell count: adjusted rate ratios (aRR) 10.65 (95% CI 6.11, 18.57), 3.40 (95% CI 2.05, 5.65), 1.77 (95% CI 1.06, 2.96) and 1.84 (95% CI 1.09, 3.12) for individuals with CD4 cell counts less than 50, 50-199, 200-349 and 350-499 cells/microl, respectively, compared with at least 500 cells/microl; and black African vs. white ethnicity [aRR 2.93 (95% CI 1.89, 4.54)]. HIV risk group, shorter time on cART, later calendar period and unsuppressed viral load were also independently associated with incident tuberculosis.


CONCLUSIONS
Tuberculosis incidence among people attending UK HIV clinics is substantial, particularly among those with non-white ethnicity and low CD4 cell counts, even after starting cART. Earlier HIV diagnosis is needed in order to implement interventions to prevent tuberculosis; tuberculosis preventive therapy should be considered in addition to cART.
Grant
Alison D
AD
Clinical Research Unit, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK. alison.grant@lshtm.ac.uk
Bansi
Loveleen
L
Ainsworth
Jonathan
J
Anderson
Jane
J
Delpech
Valerie
V
Easterbrook
Philippa
P
Fisher
Martin
M
Gazzard
Brian
B
Gilson
Richard
R
Gompels
Mark
M
Hill
Teresa
T
Johnson
Margaret
M
Leen
Clifford
C
Orkin
Chloe
C
Phillips
Andrew N
AN
Porter
Kholoud
K
Post
Frank
F
Walsh
John
J
Sabin
Caroline A
CA
D017088:AIDS-Related Opportunistic Infections / Q000188:drug therapy / Q000453:epidemiology / Q000208:ethnology / Q000517:prevention & control*; D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D012307:Risk Factors; D040242:Risk Reduction Behavior; D014376:Tuberculosis / Q000453:epidemiology / Q000208:ethnology / Q000517:prevention & control*; D006113:United Kingdom; D019562:Viral Load