Table 1.
Subject demographics for study populations.
Table 2.
Demographics for older versus younger control subjects.
Figure 1.
Typical example of genioglossus data.
Shown is a typical example of two selective concentric MUP (left) and CNMACRO MUP (right) templates from a recording from an older (top panel; 71 years, AHI 2.8) and younger (lower panel; 38 years, AHI 9.3) subject. Calibrations of the selective concentric needle MUP and CNMACRO MUP, 500 µV and 2 ms. The duration of the MUP as measured between the onset of the first and the offset of the last deviation from the baseline of the MUP are indicated by the vertical dotted lines. The duration is marked relative to the timing of the young MUPs to indicate the lengthening of the MUPs in older subjects.
Figure 2.
Mean feature values of selective concentric needle MUPs and concentric needle macro (CNMACRO) MUPs.
Each panel represents mean values of selected features from all the individual MUPs and CNMACRO MUPs. The solid columns depict values from older subjects and the shaded columns represent values from younger subjects. Significance is given where appropriate in the respective panels.
Figure 3.
Histogram display with the featured values of selective concentric needle MUPs and concentric needle macro (CNMACRO) MUPs from all 40 subjects.
The solid filled columns depict values from younger subjects and the white columns represent values from younger subjects. Medians are indicated by arrows in each panel and in each circumstance the filled arrow indicates the median of younger subjects and the unfilled arrow depicts the median of older subjects. Significance is given where appropriate in the respective panels.
Figure 4.
Duration of MUPs plotted versus subject age.
Mean MUP duration (ms) versus age (years). The MUPs with longer durations are associated with increased age. The Pearson correlation coefficient was calculated from the mean value of all 40 subjects (r = 0.660; P = 0.00000359). The open black circles depict values from older control subjects while solid circles depict values from older obstructive sleep apnea subjects. The open grey circles depict values from younger control subjects while solid circles depict values from younger obstructive sleep apnea subjects.
Table 3.
Key results from all 40 subjects.
Figure 5.
Mean relative irregularity coefficient versus minimal oxygen saturation.
More complex motor unit potentials (MUPs), as calculated with the relative irregularity, are associated with minimal oxygen saturation detected from the overnight polysomnography. The Pearson correlation coefficient was calculated from the mean value of 37 subjects (r = 0.633; P = 0.0000267). The three squares on the X-axis represent relative irregularity coefficient data from subjects whose minimal oxygen data were not obtained (not included in the correlation).
Table 4.
Key results for the 18 control subjects.