Table 1.
Demographic and sleep-disordered breathing data in the study cohort and in the 3 BMI groups. Data are presented as mean ± standard deviation or % where indicated. Significant differences between the 3 BMI groups are in bold (p<0.05).
| All | BMI < 30 kg/m2 |
BMI 30 −< 35 kg/m2 |
BMI ≥ 35 kg/m2 |
p-value for comparison between groups* |
|
|---|---|---|---|---|---|
| n = 452 | n = 156 | n = 162 | n = 134 | ||
| Age (years) | 54.4 ± 10.6 | 55.1 ± 9.4 | 54.9 ± 10.9 | 52.8 ± 11.3 | 0.13 |
| % of males | 83.4 | 86.5 | 83.3 | 79.9 | 0.31 |
| Body mass index (kg/m2) | 32.7 ± 5.3 | 27.6 ± 2.0 | 32.2 ± 1.4 | 39.2 ± 3.7 | N/A |
| Current smokers (%) | 24.0 | 27.6 | 22.8 | 21.1 | 0.40 |
| Sleep disordered breathing | |||||
| Apnea-hypopnea index (events/hour) | 40.2 ± 16.1 | 38.9 ± 15.2 | 41.4 ± 16.8 | 40.4 ± 16.3 | 0.38 |
| Oxygen desaturation index (events/hour) | 31.5 ± 14.1 | 28.5 ± 12.4 | 31.7 ± 14.9 | 34.8 ± 14.2 | 0.0006 |
| Minimum SaO2 (%) | 77.2 ± 7.2 | 78.7 ± 5.9 | 77.6 ± 7.3 | 74.9 ± 8.0 | <0.0001 |
| Hypoxia time (minutes) | 42.3 ± 60.7 | 29.7 ± 41.7 | 39.0 ± 60.9 | 61.1 ± 73.7 | <0.0001 |
| Epworth Sleepiness Score | 11.6 ± 4.9 | 12.0 ± 4.8 | 11.3 ± 4.8 | 11.7 ± 5.0 | 0.46 |
| Medical history | |||||
| Hypertension (%) | 44.4 | 34.2 | 44.4 | 56.4 | 0.0008 |
| Cardiovascular disease (%) | 17.8 | 16.2 | 17.4 | 20.2 | 0.68 |
| Diabetes (%) | 11.1 | 5.2 | 8.7 | 20.9 | 0.0001 |
| Leptin levels (ng/ml)† | 10.6 (9.9–11.3) | 6.7 (6.0–7.3) | 10.8 (9.8–11.8) | 17.9 (16.1–19.9) | <0.0001 |
*
One-way ANOVA for continuous variables and Pearson chi-square test for percentages.
†
Geometric mean and 95% confidence interval determined from exponentiation of log transformed values.