The following is a summary of “Does peak expiratory flow moderate trajectories of cognitive function among individuals with lung diseases? A longitudinal analysis of the National Health and Aging Trends Study,” published in the FEBRUARY 2023 issue of Pulmonology by Wiley, et al.

Chronic respiratory illnesses and impaired cognitive function can coexist. Peak expiratory flow (PEF) may affect changes in cognitive performance, however, it was unclear. Therefore, for a study, researchers sought to determine if peak expiratory flow affected the development of memory, visuospatial skills, and executive function in people with chronic respiratory conditions.

The National Health and Aging Trends Study data on people with lung disorders were analyzed in this study. They estimated clock drawing and immediate and delayed recollection trajectories throughout a 10-year follow-up using multivariable-adjusted generalized linear mixed models. Using sex-specific peak expiratory flow values at the 10th, 50th, and 90th percentiles, the interaction between PEF and time was displayed.

Time-by-PEF interactions were discovered in females for both immediate (n = 489, t = 2.73, P<0.01) and delayed (n = 489, t = 3.38, P<0.01) recall. When it comes to delayed recall, females in the 10th vs. 90th percentile of PEF experienced declines of 0.17 vs. 0.032 words/year and 0.14 vs. 0.065 words/year, respectively. Recall decreased linearly over 10 years among males (immediate recall: n = 296, t = −3.08, P < 0.01; delayed recall: n = 292, t = −2.46, P = 0.02), with no interaction with PEF. Both sexes’ clock drawing scores did not change over time or depend on the PEF (females: n = 484, t = 0.25, p = 0.81; males: n = 291, t = −0.61, P = 0.55).

Over a 10-year period of follow-up, females with the lowest PEF values showed the largest rates of decrease in both immediate and delayed recall, but men showed similar declines in memory outcomes across all PEF levels. Over a ten-year period, clock drawing scores in both sexes were consistent.

Reference: resmedjournal.com/article/S0954-6111(23)00008-2/fulltext