Association between latent tuberculosis and ischemic heart disease: a hospital-based cross-sectional study from Saudi Arabia

INTRODUCTION: atherosclerosis could be a sequela of long-term activation of cell-mediated immunity as the case of latent tuberculosis infection. Atherosclerosis is the main pathological event in ischemic heart disease. The present study aimed to assess the prevalence of Latent tuberculosis infection (LTBI) among patients with ischemic heart disease (IHD) and to detect the association between both diseases. METHODS: this cross-sectional study included 98 patients with a history of previously diagnosed ischemic heart disease who did a multi-detector computed tomography coronary angiogram (MDCTCA). Detailed clinical examination and investigations as chest X-ray and sputum examination were done for those with positive QuantiFERON-TB Gold test (QFT) to exclude active tuberculosis (TB). Participants having positive QFT results but with no evidence of active TB were considered as LTBI positive. RESULTS: the prevalence of LTBI in patients with IHD was 19.3% as only nineteen of the ninety-eight patients were diagnosed with latent tuberculosis infection using the QuantiFERON serum test. Eighty-four percent (84.2%) of patients with LTBI had coronary artery atherosclerosis (CAA) compared to only 55.6% in patients without LTBI with a statistically significant difference. In multivariable analysis, Diabetes Mellitus (DM) (AOR 0.179, 95% C.I.: 0.03-0.967), and LTBI (AOR 1.024, 95% C.I.: 1.002-1.736) were significantly associated with coronary artery atherosclerosis (p=0.0001, and p= 0.003 respectively). CONCLUSION: the prevalence of latent tuberculosis infection among patients with ischemic heart diseases is high. Among different factors that are already well known to precipitate ischemic heart disease, latent tuberculosis should be considered.