Work

Long-term effects of smoking status on respiratory function in male survivors of the Great East Japan Earthquake and Tsunami: the RIAS study

Year: 2026

Type: article

Abstract: BACKGROUND: Smoking-related respiratory decline is well established, but whether tsunami-related flood damage modifies this association among disaster survivors remains unclear. We examined 9-year changes in respiratory function by baseline smoking status among male survivors of the Great East Japan Earthquake and Tsunami, focusing on a potential interaction with flood damage. METHODS: We analyzed 1093 men in the RIAS study who completed annual surveys from 2012 to 2019. Spirometry was performed annually from 2011 to 2019. Smoking status was classified at baseline as never, former, or current smoking. Longitudinal changes in the percent-predicted vital capacity (%VC), forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC), and percent-predicted forced expiratory volume in 1 second (%FEV1) were assessed using generalized estimating equation models adjusted for clinical and lifestyle covariates. Stratified and interaction analyses evaluated modification by flood damage. RESULTS: Former and current smokers had lower FEV1/FVC than never smokers. Values of %FEV1 were also lower among former smokers and current smokers than among never smokers. Current smokers showed greater longitudinal declines in FEV1/FVC and %FEV1 than never smokers, whereas the corresponding declines in former smokers were weaker and less consistent. In the primary models, %VC did not differ significantly by smoking status. Smoking-related respiratory function patterns were broadly similar in flood-damaged and non-flood-damaged participants, and the stratified analyses showed no consistent evidence that tsunami-related flood damage modified the association. CONCLUSIONS: Among male Great East Japan Earthquake and Tsunami survivors, the smoking-related decline in obstructive respiratory indices was broadly similar in flood-damaged and non-flood-damaged participants; we found no consistent evidence that flood damage modified this association. These findings support smoking cessation and periodic lung function monitoring across flood-damage strata, while not excluding acute or persistent respiratory effects of disaster exposure.

Source: Environmental Health and Preventive Medicine

DOI: 10.1265/ehpm.26-00089