Association of iron deficiency anemia with tuberculosis in Taiwan: A nationwide population-based study

Abstract

Background Iron deficiency is associated with decreased cellular immunity, which may predispose patients with iron deficiency anemia (IDA) to increased risk of developing tuberculosis (TB). This study investigated the relationship between newly diagnosed IDA and TB infection in Taiwan. Methods The study included data on 21,946 patients with incident IDA and 87,555 non-IDA controls from a national database covering the period 2000–2012. IDA and non-IDA subjects were matched 1:4 on age, gender, and index year. The follow-up period was defined as the time from the initial IDA diagnosis to the date of developing TB or 31 December 2013. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals, with the control group as the reference. Results The adjusted hazard ratio of TB for the IDA group was 1.99 (95% confidence interval, 1.77–2.25) compared with the control group. The subgroup analysis showed that for both genders, all age groups, and patients with diabetes mellitus, hyperlipidemia, hypertension, cancer, chronic obstructive pulmonary disease, and hepatitis B virus infection, the IDA group had significantly higher TB incidence. The association was significantly stronger within the 5 years after new IDA diagnosis for both genders and all age groups. Conclusions Higher TB incidence was discovered in the IDA group, especially for patients with comorbidities.

Anemia as a risk factor for tuberculosis: a systematic review and meta-analysis

“…Of the included 17 articles, 2 (11.8%) research articles were published in years of 2005 [ 27 ] and 2011 [ 28 ] (one in each year’s) while 5 (29.4%) of them were published in the year of 2013 [ 29 , 31 , 32 , 33 , 35 ] and 1 (5.9%) of the research articles was published in the year of 2014 [ 11 ]. Nine (52.9%) of the included articles were published between 2015 and 2019 (4 (23.5%) in 2015 [ 20 , 21 , 30 , 34 ], 2 (11.8%) in 2016 [ 22 , 24 ], and 3 (17.6%) in 2019 [ 10 , 17 , 23 ]). Three of the included studies were cross-sectional studies and were conducted in South Africa [ 11 ], Cameroon [ 29 ], and Nigeria [ 24 ].…”

“…It is also a known risk factor for some chronic diseases [ 41 ]. In the current systematic review and meta-analysis, majority of the included studies showed that anemia was a higher predicator of TB [ 10 , 11 , 17 , 22 , 27 – 29 , 30 , 31 ]. However, some studies showed that anemia was not the risk of TB [ 20 , 24 , 33 ].…”

“…The remaining 12 studies were cohort studies of which 8 (66.67%) were conducted in Africa (1 in south Africa [20], 2 in Tanzania [21,33], 1 Nigeria [34], 1 Gambia [32], and 3 in Ethiopia [10,22,30]). The other 4 cohort studies were conducted in Taiwan [17], Brazil [31], Cambodia [35], and Myanmar [23]. Based on the study participant, all of the cross-sectional and case-control studies were conducted on adults.…”

“…The assessment of potentially modifiable risk factors is a vital for the development of TB control policies [ 17 ]. Accordingly, some TB risk factors have been known for decades, including systemic diseases such as diabetes mellitus and chronic kidney disease as well as tobacco smoking, alcohol use, body mass index, silicosis, human immunodeficiency virus (HIV) infection, splenectomy, and gastrectomy [ 17 , 18 ]. Under-nutrition, refugee, homeless, and direct contact with active TB are also risk factors for TB [ 18 ].…”

Systemic Inflammation Associated with Immune Reconstitution Inflammatory Syndrome in Persons Living with HIV

“…Consequently, this process promotes HIV replication through modulation of host redox metabolism, promoting lymphocyte and macrophage-mediated inflammatory response [ 63 ]. In comparison to individuals with mono-infections, those with HIV-TB co-infection express higher levels of inflammatory cytokines such as IL-6, TNF-ɑ, IL-10, and IL-1-β ( Figure 3 ) [ 64 , 65 , 66 , 67 ]. As a consequence of chronic SI, anemia may develop and impact treatment success with antitubercular and antiretroviral therapy, in addition to the risk of IRIS development (reviewed in [ 68 ]).…”