Diabetes and the risk of tuberculosis: a neglected threat to public health?
OBJECTIVE
Tuberculosis (TB) remains a major global public health problem. In the past, a relationship between TB and diabetes mellitus (DM) was recognized, and its importance was acknowledged through joint treatment clinics. However, this is rarely highlighted in current research or control priorities. This paper aims to evaluate the evidence for an association between these two diseases.


METHODS
A Medline literature search was undertaken, supplemented by checking references and contacting experts. We critically appraised studies that quantified the association between TB and DM, and were published after 1995. We assessed study quality according to criteria such as sample size, method of selection of cases and controls, losses to follow-up, quality and method of control of confounding, and summarized the results narratively and in tabular form.


RESULTS
All studies identified statistically significant and clinically important associations, with the increase in risk or odds of TB varying between 1.5- and 7.8-fold for those with DM. Risk was highest at younger ages. Most studies had not measured and controlled adequately for potential major confounders.


CONCLUSIONS
There is strong evidence for an association between TB and DM, which has potential public health implications. Further well-designed studies are needed to assess the magnitude precisely.
Stevenson
Catherine R
CR
Medical Research Council Epidemiology Unit, Elsie Widdowson Laboratory, Fulbourn Road, Cambridge CB1 9NL, UK.
Critchley
Julia A
JA
Forouhi
Nita G
NG
Roglic
Gojka
G
Williams
Brian G
BG
Dye
Christopher
C
Unwin
Nigel C
NC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003920:Diabetes Mellitus; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011634:Public Health; D018570:Risk Assessment; D014376:Tuberculosis / Q000209:etiology*