Mortality risk in patients with preserved ratio impaired spirometry: assessing the role of physical activity

Background: While all-cause mortality is reportedly increased in preserved ratio impaired spirometry (PRISm), no remedial efforts have been suggested. Aim: To study the ability of physical activity (PA) on reducing the morality increased in PRISm patients. Design: We prospectively enrolled a cohort of Taiwanese adults from 1994 to 2018 in a health surveillance program. Methods: Mortality risks of those who were inactive were compared against those meeting the current recommendation of 150 min/week of PA. Cox proportional hazards models were used for hazard ratios and life table method was for estimating loss of life expectancy. Results: A total of 461 183 adults were enrolled. Among them, one-seventh of the cohort (65 832 or 14.3%) had PRISm, and 53.1% were inactive. Those who were inactive with PRISm had 28% increased mortality from all-cause, 45% from cardiovascular diseases (CVDs) and 67% from respiratory disease, with a 3-year reduction in life expectancy (males, 3.72 and females, 2.93). In PRISm patients who met the exercise recommendation, excess mortality was reduced by two-third, both all-cause (from 28% to 9%) and CVD (from 45% to 15%). Conclusion: PRISm involves a large portion of general population (14.3%) and shortens life expectancy by 3 years. More than half of the subjects were physically inactive, and adherence to 150 min/week of PA was associated with a two-third reduction of excess mortality from all cause and from CVD. Recommending PA among those with PRISm might be highly beneficial, although exercise alone may not eliminate all risks associated with PRISm.