Anaemia of chronic disease among pulmonary tuberculosis patients is associated with inflammatory marker at the start of intensive phase

Abstract

ABSTRACT Tuberculosis (TB) disrupts iron balance through systemic inflammation. Pulmonary tuberculosis (PTB) is linked to diverse anaemia types, necessitating intricate haematological and biochemical assessments for diagnosis. This study aims to describe the prevalence of anaemia of chronic disease (ACD), iron deficiency anaemia (IDA) among PTB patients and factors associated with these types of anaemia. A cross-sectional analysis was conducted from community-based cohort study involving sputum-positive PTB patients from 2018 to 2020 in urban Puducherry. Participants were enrolled from 10 primary health centres within 2 weeks of initiating anti-tubercular treatment (ATT). Blood samples were collected for assessing haematological and biochemical parameters. The sTfR/log ferritin ratio was used to distinguish between ACD and IDA. Data were captured using Epicollect5 and analysed using STATA V14. Of the 176 PTB patients included, 63.07% (111/176) had anaemia, with ACD being the predominant type (84.6%, 94/111). The C-reactive protein (CRP) levels were higher among the anaemic group [40.77 (16.66-58.51) mg/dl vs 24.65 (14.23-47.26) mg/dl] and higher among the ACD as compared to IDA [46.9 (22.3-61.2) vs 20.8 (13.0-39.1) mg/dl]. Undernourished [adjusted prevalence ratio (APR) =3.43; confidence interval (CI): 1.21-9.69] and patients having low risk of dependence on tobacco [APR = 1.52; CI: 1.10-2.11] had higher risk of ACD. Female patients had higher risk of IDA [APR = 4.95, P < 0.01]. The largest proportion of the PTB participants with anaemia had ACD. Acute-phase reactant and inflammatory marker are increased among newly diagnosed new sputum smear-positive (NSP) PTB participants at the start of ATT. Addressing inflammation is needed for combating anaemia in PTB patients.