Table 1. Respiratory function in 105 monotonic dystrophy type 1 (DM1) patients, normal weight (body mass index [BMI] < 25 kg/m2) and overweight (BMI ≥ 25 kg/m2).
| DM1 | BMI < 25 kg/m2 | BMI ≥ 25 kg/m2 | ||||
|---|---|---|---|---|---|---|
| Measurementa | Mean in % (SD)b | Mean in % (SD)b | N = 43c | Mean in % (SD)b | N = 62c | p-valued |
| Gender (% men) | 60.0% | 62.8% | 43 | 58.1% | 62 | 6.27 x 10−1 |
| Age (years) | 46.2 (12.0) | 45.5 (12.4) | 43 | 46.7 (11.8) | 62 | 6.14 x 10−1 |
| BMI (kg/m2) | 26.4 (5.7) | 21.7 (2.7) | 43 | 29.6 (5.0) | 62 | |
| FFMI (%cut-off) | 96.5 (14.3) # | 87.0 (10.3) | 36 | 106.3 (10.6) | 35 | 4.96 x 10−11 *** |
| FEV1 (%pred.) | 82.9 (18.6) ## | 87.3 (16.6) ## | 42 | 79.8 (19.3) ## | 61 | 3.72 x 10−2 * |
| VC (%pred.) | 83.9 (18.9) ## | 87.7 (17.1) | 43 | 81.2 (19.8) | 62 | 8.58 x 10−1 |
| FEV1/VC (%) | 101.1 (7.9) | 100.9 (8.6) | 42 | 101.4 (7.5) | 61 | 7.55 x 10−1 |
| FIV1 (%pred.) | 79.6 (21.4) ## | 82.4 (20.0) ## | 38 | 78.6 (22.1) ## | 60 | 3.81 x 10−1 |
| FRC (%pred.) | 72.3 (20.0) ## | 86.6 (17.5) ## | 39 | 62.8 (15.4) ## | 59 | 1.52 x 10−9 *** |
| RV (%pred.) | 71.1 (16.9) ## | 79.8 (19.2) ## | 40 | 65.3 (12.1) ## | 59 | 8.01 x 10−5 *** |
| ERV (%pred.) | 73.1 (36.9) ## | 98.5 (32.5) | 39 | 60.3 (31.7) ## | 59 | 1.53 x 10−7 *** |
| TLC (%pred.) | 79.0 (14.9) ## | 84.1 (12.6) ## | 41 | 75.4 (15.4) ## | 59 | 2.40 x 10−3 ** |
| DLCO/VA (%pred.) | 107.4 (16.2) ## | 102.8 (13.1) | 38 | 110.6 (17.4) ## | 56 | 1.49 x 10−2 * |
| PEmax (%pred.) | 55.7 (23.5) ## | 50.5 (21.3) ## | 40 | 59.6 (24.5) ## | 53 | 5.73 x 10−2 |
| PImax (%pred.) | 65.0 (23.4) ## | 63.5 (23.5) ## | 40 | 66.1 (23.5) ## | 51 | 5.98 x 10−1 |
a Percentage predicted (%pred.) of FFMI (%cut-off): fat-free mass index (kg/m2) as percentage of cut-off values (normal values for mean FFMI > 16.0 kg/m2 and for women FFMI > 15.0 kg/m2); FEV1: forced expiratory volume in 1 second; VC: vital capacity; FIV1: forced inspiratory volume in 1 second; FRC: functional residual capacity; RV: residual volume; ERV: expiratory reserve volume; TLC: total lung capacity; DLCO/VA: diffusion capacity corrected for alveolar volume; PEmax: maximal expiratory mouth pressure; PImax: maximal inspiratory mouth pressure.
b SD: standard deviation;
# p < 0.05;
## p < 0.001 for a paired t-test between measured and predicted values within each group.
c Number of patients with data available for each measurement.
d p-values are given for two-sample t-tests (continuous data) or Chi-squared tests (discrete data), as appropriate, between the groups of BMI.
* p < 0.05;
** p < 0.01;
*** p < 0.001.