Table 3.
Vascular reactivity and cardiovascular magnetic resonance results: cross-sectional study
| Variable | Control Subjects (n = 28) | T2DM Only (n = 27) | OSA Only (n = 29) | T2DM + OSA (n = 57) | OSA Main Effect | T2DM Main Effect | OSA × T2DM Interaction |
|---|---|---|---|---|---|---|---|
| Macrovascular reactivity | |||||||
| Flow-mediated dilation, % | 6.1 ± 4.0 | 7.3 ± 3.6 | 6.8 ± 4.5 | 4.8 ± 2.9 | 0.9 (−1.1 to 2.9) | 1.3 (−0.7 to 3.3) | −3.1 (−5.6 to −0.6)* |
| NTG-induced dilation, % | 16.5 ± 8.2 | 17.0 ± 6.9 | 15.3 ± 8.4 | 13.6 ± 7.5 | −1.2 (−4.1 to 1.7) | −0.3 (−2.8 to 2.2) | |
| Microvascular reactivity | |||||||
| ACh-induced dilation, % | 29.9 ± 22.9 | 36.9 ± 29.9 | 44.7 ± 36.1 | 31.2 ± 26.2 | 4.6 (−7.0 to 16.2) | −4.0 (−14.4 to 6.4) | |
| SNP-induced dilation, % | 28.9 ± 30.4 | 31.9 ± 27.0 | 35.7 ± 26.7 | 33.6 ± 29.7 | 9.4 (−2.0 to 20.8) | 2.5 (−7.7 to 12.7) | |
| CMR imaging | |||||||
| LV mass, g | 104.6 ± 24.8 | 96.0 ± 19.3 | 98.0 ± 32.5 | 109.1 ± 32.8 | −4.0 (−13.4 to 5.4) | 1.1 (−7.3 to 9.5) | |
| LV end-diastolic volume, ml | 158.0 ± 32.0 | 135.3 ± 22.9 | 129.5 ± 30.2 | 139.6 ± 33.4 | −27.7 (−43.2 to −12.2)† | −16.8 (−30.9 to −2.7)* | 22.4 (3.2 to 41.6)* |
| LV end-systolic volume, ml | 62.5 ± 18.7 | 52.4 ± 14.3 | 47.9 ± 16.9 | 51.2 ± 19.2 | −6.6 (−13.1 to −0.1)* | −1.9 (−7.6 to 3.8) | |
| LV ejection fraction, % | 61.0 ± 6.5 | 61.6 ± 5.8 | 63.6 ± 6.7 | 64.2 ± 6.6 | 1.0 (−1.5 to 3.5) | 0.0 (−2.4 to 2.4) | |
| RV mass, g | 34.4 ± 7.0 | 29.0 ± 5.1 | 28.8 ± 9.3 | 30.1 ± 8.2 | −2.6 (−5.7 to 0.5) | −1.5 (−4.2 to 1.2) | |
| RV end-diastolic volume, ml | 174.1 ± 31.7 | 144.8 ± 26.5 | 141.4 ± 45.1 | 146.4 ± 32.0 | −32.0 (−49.1 to −14.9)† | −21.6 (−36.5 to −6.7)† | 23.2 (2.6 to 43.8)* |
| RV end-systolic volume, ml | 79.6 ± 20.0 | 61.3 ± 16.2 | 54.5 ± 18.3 | 58.8 ± 21.7 | −20.4 (−30.8 to −10.0)† | −13.0 (−22.0 to −4.0)† | 14.4 (1.9 to 26.9)* |
| RV ejection fraction, % | 54.7 ± 6.1 | 58.1 ± 6.3 | 59.1 ± 8.0 | 60.7 ± 6.7 | 2.2 (−0.5 to 4.9) | 1.8 (−0.6 to 4.2) | — |
Definition of abbreviations: ACh = acetylcholine; CMR = cardiovascular magnetic resonance; LV = left ventricular; NTG = nitroglycerin; OSA = obstructive sleep apnea; RV = right ventricular; SNP = sodium nitroprusside; T2DM = type 2 diabetes mellitus.
Data are presented as mean ± SD; all values are unadjusted. Analysis of covariance models with an OSA ± T2DM interaction term were produced; if the interaction was significant (P × 0.05), the interaction effect and main effects are presented as the unstandardized β (95% confidence interval [CI]). If the interaction was not significant, the interaction term was removed, and the main effects are presented as the unstandardized β (95% CI). All models were adjusted for age, sex, and body mass index. The sample sizes refer to the primary outcome (flow-mediated dilation) for which there was no missing data; sample sizes varied for the other outcomes listed.
P ≤ 0.05.
P ≤ 0.01.