Trajectory and mortality of preserved ratio impaired spirometry: the Rotterdam Study.

Preserved ratio impaired spirometry (PRISm) is a heterogeneous condition but its course and disease progression remain to be elucidated. We aimed to examine its prevalence, trajectories and prognosis in the general population.In the Rotterdam Study (population-based prospective cohort) we examined prevalence, trajectories and prognosis of subjects with normal spirometry (controls; forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ≥0.7, FEV1  ≥80%), PRISm (FEV1/FVC ≥0.7, FEV1 <80%) and chronic obstructive pulmonary disease (COPD) (FEV1/FVC <0.7) at two study visits. Hazard ratios with 95% confidence intervals for mortality (until December 30, 2018) were adjusted for age, sex, body mass index, current smoking and pack-years.Of 5487 subjects (age 69.1±8.9 years; 7.1% PRISm), 1603 were re-examined after 4.5 years. Of the re-examined PRISm subjects, 15.7% transitioned to normal spirometry and 49.4% to COPD. Median lung function decline was highest in subjects with incident PRISm (FEV1 -92.8 mL·year-1, interquartile range (IQR) -131.9- -65.8 mL·year-1; FVC -93.3 mL·year-1, IQR -159.8- -49.1 mL·year-1), but similar in persistent PRISm (FEV1 -30.2 mL·year-1, IQR -67.9- -7.5 mL·year-1; FVC -20.1 mL·year-1, IQR -47.7-21.7 mL·year-1) and persistent controls (FEV1 -39.6 mL·year-1, IQR -64.3--12.7 mL·year-1; FVC -20.0 mL·year-1, IQR -55.4-18.8 mL·year-1). Of 5459 subjects with informed consent for follow-up, 692 (12.7%) died during 9.3 years (maximum) follow-up: 10.3% of controls, 18.7% of PRISm subjects and 20.8% of COPD subjects. Relative to controls, subjects with PRISm and COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2-4 had increased all-cause mortality (PRISm: HR 1.6, 95% CI 1.2-2.0; COPD GOLD 2-4: HR 1.7, 95% CI 1.4-2.1) and cardiovascular mortality (PRISm: HR 2.8, 95% CI 1.5-5.1; COPD 2-4: HR 2.1, 95% CI 1.2-3.6). Mortality within <1 year was highest in PRISm, with patients often having cardiovascular comorbidities (heart failure or coronary heart disease; 70.0%).PRISm is associated with increased mortality and this population encompasses at least three distinct subsets: one that develops COPD during follow-up, a second with high cardiovascular burden and early mortality, and a third with persistent PRISm and normal age-related lung function decline.

Normal spirometry values in healthy elderly: the Rotterdam Study.

Although many different reference values for spirometry are available from various studies, the elderly are usually underrepresented. Therefore, our objective was to assess reference values in a sample of healthy participants from a prospective population-based cohort study, including a large proportion of elderly. We included spirometry measurements of healthy, never smokers, from the Rotterdam Study and excluded participants with respiratory symptoms or prescriptions for respiratory medication. Age- and height-specific curves for the 5th (lower limit of normal) and the 50th (median) percentile of Forced Expiratory Volume in 1 s (FEV1), Forced Vital Capacity (FVC), and the ratio (FEV1/FVC) were calculated by quantile regression models. The group of healthy elderly study subjects consisted of 1,125 individuals, with a mean age of 68 years, ranging from 47 to 96 years of age. Sex stratified equations for the median and the lower limit of normal were calculated adjusted for age and height. In this study, we report age- and height-dependent reference limits for FEV1, FVC, and FEV1/FVC in a large population, and prediction equations for the lower limit of normal and median values for a sample containing a large proportion of healthy elderly.