Reduced pulmonary function, low-grade inflammation and increased risk of total and cardiovascular mortality in a general adult population: Prospective results from the Moli-sani study

Aim: to investigate the relation of pulmonary function impairment with mortality and the possible mediation by low-grade inflammation in a general adult population. Methods: A prospective investigation was conducted on 14,503 individuals from the Moli-sani study (apparently free from lung disease and acute inflammatory status at baseline; 2005-2010). The 2012 Global Lung Function Initiative percent predicted (% pred) value of forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC (FEF25-75) and FEV1 quotient (FEV1Q) index were used. C-reactive protein and blood cell counts were measured and a score of subclinical inflammation (INFLA-score) was calculated. Results: Over a median follow-up of 8.6y, 503 deaths (28.9% cardiovascular) were ascertained. Total mortality increased by 19% for each decrease in 1 standard deviation of FEV1% pred or FVC% pred (Hazard Ratio:1.19; 95% CI:1.11-1.28 and 1.19; 1.10-1.28, respectively). Comparable findings for FEV1Q (1.30; 1.15-1.47) were observed. A statistically significant increased risk in cardiovascular mortality of 23%, 32% and 49% was observed for 1 standard deviation decrease of FEV1% pred, FVC% pred and FEV1Q, respectively. INFLA-score mediated the association of FEV1% pred and FEV1Q with cardiovascular mortality by 22.3% and 20.1%, respectively. Subjects with FEV1, FVC lower than normal limit showed increased risk both in total and cardiovascular mortality. Abnormal FEF25-75 values were associated with 33% (1.33; 1.02-1.74) total mortality risk. Conclusions: Obstructive lung function impairment was associated with decreased survival. Low-grade inflammation mainly mediated the association of FEV1 with cardiovascular mortality.

Automated summary

This study investigated the association between pulmonary function impairment and mortality in a general adult population. The findings showed that obstructive lung function impairment was associated with decreased survival, with low-grade inflammation mainly mediating the association of FEV1 with cardiovascular mortality. Subjects with FEV1 and FVC values lower than the normal limit had increased risk in both total and cardiovascular mortality. Abnormal FEF25-75 values were also linked to higher total mortality risk.