Background: In a large cross-sectional analysis we analyzed various vascular parameters in the renal, retinal and systemic circulation, with the goal to identify which vascular parameter of early organ damage is the earliest that can be clinically detected.
Methods: In 111 patients with type 2 diabetes (T2DM) and 54 subjects without T2DM we assessed urinary albumin creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR), retinal capillary flow (RCF), intercapillary distance (ICD) as parameters of capillary rarefaction, wall-to-lumen ratio (WLR) of the retinal arterioles [all assessed by Scanning Laser Doppler Flowmetry], and central systolic pressure(cSBP) and central pulse pressure (cPP) [measured by pulse wave analysis, Syphygmocor].
Results: Compared to subjects without T2DM, patients with type 2 diabetes (duration: mean 63.9 ± 56.4, range 1-271 months) were older (59.8 ± 7.3 vs. 43.4 ± 12.9 years, p<0.001), more females (33.3 vs. 20.4 %, p<0.001) but 24-hour systolic and diastolic blood pressure did not differ between the two groups (129±11/79±8 vs. 130±11/77±6 mmHg).
| Non-T2DM-subjects (n=54) | Patients with T2DM (n= 111) | Unadjusted p-value | Age- gender- adjusted p-value | Adjusted p-value (potential confounders) | |
| ICD (µm) | 20.8 ± 3.5 | 23.9 ± 5.1 | <0.001 | <0.001 | 0.001 |
| RCF (AU) | 310.4 ± 55.1 | 297.8 ± 72.9 | 0.15 | 0.35 | 0.72 |
| WLR (-) | 0.35 ± 0.08 | 0.38 ± 0.11 | 0.04 | 0.67 | 0.90 |
| eGFR (ml/min/1.73m²) | 95.9 ± 17.3 | 91.7 ± 9.9 | 0.10 | <0.001 | <0.001 |
| 7.9 ± 7.5 | 21.3 ± 86.6 | <0.001 | 0.55 | 0.91 | |
| cPP (mmHg) | 34.8 ± 10.6 | 41.8 ± 11.7 | 0.001 | 0.31 | <0.001 |
| RCF (AU) | 310.4 ± 55.1 | 297.8 ± 72.9 | 0.15 | 0.35 | 0.72 |
| Non-T2DM-subjects (n=54) | Patients with T2DM (n= 111) | Unadjusted p-value | Age- gender- adjusted p-value | Adjusted p-value (potential confounders) | |
| ICD (µm) | 20.8 ± 3.5 | 23.9 ± 5.1 | <0.001 | <0.001 | 0.001 |
| RCF (AU) | 310.4 ± 55.1 | 297.8 ± 72.9 | 0.15 | 0.35 | 0.72 |
| WLR (-) | 0.35 ± 0.08 | 0.38 ± 0.11 | 0.04 | 0.67 | 0.90 |
| eGFR (ml/min/1.73m²) | 95.9 ± 17.3 | 91.7 ± 9.9 | 0.10 | <0.001 | <0.001 |
| 7.9 ± 7.5 | 21.3 ± 86.6 | <0.001 | 0.55 | 0.91 | |
| cPP (mmHg) | 34.8 ± 10.6 | 41.8 ± 11.7 | 0.001 | 0.31 | <0.001 |
| RCF (AU) | 310.4 ± 55.1 | 297.8 ± 72.9 | 0.15 | 0.35 | 0.72 |
Conclusion: These data suggest that at similar blood pressure capillary rarefication in the retinal circulation (ICD), eGFR in the renal circulation and central pulse pressure (cPP) of large arteries are earlier detectable than vascular remodeling of the micro- (WLR, RCF, UACR) and macrocirculation (cSPB) in patients with T2DM.
R.E. Schmieder: Consultant; Self; AstraZeneca, Bayer AG, Berlin-Chemie AG, Boehringer Ingelheim GmbH. Other Relationship; Self; Boehringer Ingelheim GmbH. Speaker's Bureau; Self; Daiichi Sankyo Company, Limited. Other Relationship; Self; Novartis AG. Consultant; Self; Novartis AG. Speaker's Bureau; Self; Servier. D. Kannenkeril: None. M.V. Karg: None. A. Bosch: None. J.M. Harazny: None. C. Ott: None.
