Anemia and high-output cardiac hypertrophy in Tanzania and Haiti: a cross-sectional analysis

BACKGROUND: Low- and middle-income countries (LMICs) face a growing burden of cardiovascular disease (CVD) that is not fully explained by traditional risk factors like hypertension. Anemia is highly prevalent in LMICs and may be an important non-traditional CVD risk factor. We evaluated the association between anemia and preclinical CVD, including left ventricular hypertrophy (LVH) and other echocardiographic measures, in two diverse LMIC settings. METHODS: This was a cross-sectional analysis of data from two separate cohorts of adults in Mwanza, Tanzania (n = 999; data collected 2022-2023) and Port-au-Prince, Haiti (n = 3,005; data collected 2019-2021). Participants underwent clinical examinations, laboratory testing, and echocardiography. Models assessing the relationship between anemia and echocardiographic outcomes were adjusted for age, sex, HIV status, blood pressure, and body mass index. RESULTS: Anemia prevalence was 23% in Tanzania and 32% in Haiti. Despite lower blood pressure and BMI among anemic participants, moderate/severe anemia were strongly associated with higher LVMI and LVH in both cohorts. In combined analyses, moderate/severe anemia were associated with LVMI increases of 8.4 g/m² and 29.7 g/m², respectively. Anemia was also associated with echocardiographic changes characteristic of a high-output cardiac state, including increased cardiac and stroke volume indices. Moderate/severe anemia was associated with18.2% of LVH cases in Tanzania and 9.1% in Haiti, and 34.4% among people with HIV. CONCLUSIONS: Anemia was independently associated with high-output cardiac hypertrophy in two distinct LMIC populations, underscoring anemia as a potentially modifiable CVD risk factor. Enhanced anemia screening and management could serve as a vital strategy to mitigate the rising burden of CVD in these regions.