Impact of age on breathing and resistive pressure in people with and without sleep apnea

Impact of age on breathing and resistive pressure in people with and withou t sleep apnea. J Appl Physiol 90: 1074-1082, 2001.-We investigated the effe ct of age on breathing and total pulmonary resistance (RL) during sleep by studying elderly (>65 yr) and young (25-38 yr) people without sleep apnea ( EN and YN, respectively) matched for body mass index (BMI). To determine th e impact:of sleep apnea on age-related changes in breathing, we studied eld erly and young apneic patients (EA and YA, respectively) matched for apnea and BMI. In all groups (n = 11), breathing during periods of stable sleep w as analyzed to evaluate the intrinsic variability of respiratory control me chanisms. In the absence of sleep apnea, the variability of the breathing w as similar in the elderly and young [mean (+/- SD) coefficient of variation (CV) of tidal volume (VT); wake: EN 21.0 +/- 14.9%, YN 14.7 +/- 5.5%; slee p: EN 14.0 +/- 6.0%; YN 11.5 +/- 6.4%]. In patients with sleep apnea, breat hing during stable sleep was more irregular, but there were no age-related differences (CV of VT; wake: EA 22.0 +/- 11.6%, YA 16.7 +/- 11.3%; sleep: E A 32.8 +/- 24.9%, YA 25.2 +/- 16.3%). In addition, EN tended to have a high er RL (n = 6, RL midinspiration, wake: EN 7.1 +/- 3.0; YN 9.1 +/- 6.4 cmH(2 )O.1(-1).s, sleep: EN 17.5 +/- 11.7; YN 9.8 +/- 2.0 cmH(2)O.1(-1).s). We co nclude that aging per se does not contribute to the intrinsic variability o f respiratory control mechanisms, although there may be a lower: probabilit y of finding elderly people without respiratory instability.