Pulmonary abnormalities are frequently observed in patients with heart failure (HF), but their prognostic significance has been evaluated primarily in high-income countries. In a study published in the ESC Heart Failure, Investigators assessed the relationship between lung function, HF burden, and long-term clinical outcomes in a large multinational cohort enrolled in the Global Congestive Heart Failure registry.

This sub-study included HF participants from 28 high-, middle-, and low-income countries who underwent spirometry at baseline and were followed for a median of 3.8 years. Forced expiratory volume in 1 second (FEV1) values were standardized as age-, sex-, and height-adjusted z-scores. 

Findings

• Among 3,359 patients with HF, lower FEV1 z-scores were associated with a greater burden of HF, more pronounced cardiac structural and functional abnormalities, and poorer health-related quality of life.
• Even among patients with FEV1 values within the conventionally normal range (z-score >−2), progressively lower FEV1 was associated with worsening HF severity and clinical status.
• An FEV1 z-score ≤−2 was independently associated with more than a twofold higher risk of all-cause mortality (HR 2.20; 95% CI 1.61–3.01).
• Patients with FEV1 z-score ≤−2 also had a significantly increased risk of cardiovascular mortality (HR 2.45; 95% CI 1.64–3.66).
• Reduced FEV1 was associated with a 40% higher risk of all-cause hospitalization (HR 1.40; 95% CI 1.12–1.74), with effect sizes comparable to those of established HF prognostic markers.

Investigators concluded that impaired lung function, as measured by FEV1, is independently associated with worse outcomes across the spectrum of HF. The relationship between lower FEV1 and adverse clinical outcomes was consistent across countries with differing levels of socioeconomic development, HF etiologies, HF phenotypes, and the presence or absence of airflow obstruction.