| 1. |
- Forsén, A, et al.
(författare)
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A 14-year prospective study of autonomic nerve function in Type 1 diabetic patients: association with nephropathy.
- 2004
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Ingår i: Diabetic Medicine. - : Wiley. - 1464-5491 .- 0742-3071. ; 21:8, s. 852-858
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Tidskriftsartikel (refereegranskat)abstract
- Aims Prospective studies of autonomic nerve function are rare. We have followed the progression of autonomic dysfunction in relation to nephropathy over 14 years in Type 1 diabetic patients. Methods Autonomic nerve function was assessed by heart-rate responses to deep breathing (E/I ratio) and tilting (acceleration and brake indices) and by the postural blood pressure reaction in 58 patients, 43 of whom were reassessed after 14 years. Nephropathy was evaluated by the degree of albuminuria (albuminuria > 20 µg/min or > 0.03 g/24 h) and glomerular filtration rate (51Cr-EDTA plasma clearance). The acceleration index had deteriorated after 7 years (P = 0.0155), whereas the E/I ratio (P = 0.0070) and the diastolic postural blood pressure reaction (P = 0.0054) had deteriorated 14 years after the baseline examination (age-corrected values). All those with albuminuria at the third examination showed signs of autonomic neuropathy at baseline (10 of 10) compared with only nine of 22 without (P = 0.0016). Multiple regression analysis showed that the association between autonomic dysfunction and future albuminuria was due to the E/I ratio. In addition, individuals with an abnormal postural diastolic blood pressure fall (n = 7) at baseline showed a greater fall in glomerular filtration rate more than others 7-14 years later [29 (16.5) ml/min/1.72 m2 vs. 11 (9) ml/min/1.72 m2; P = 0.0074]. Conclusion Autonomic nerve function had deteriorated after 14 years. Autonomic neuropathy and abnormal postural diastolic blood pressure falls at baseline were associated with future renal complications.
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| 2. |
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| 3. |
- Freccero, Carolin, et al.
(författare)
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Sympathetic and parasympathetic neuropathy are frequent in both type 1 and type 2 diabetic patients.
- 2004
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Ingår i: Diabetes Care. - : American Diabetes Association. - 1935-5548 .- 0149-5992. ; 27:12, s. 2936-2941
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE—The aim of this study was to evaluate the frequency of sympathetic versus parasympathetic neuropathy among type 1 and type 2 diabetic patients. RESEARCH DESIGN AND METHODS—There were 43 patients with type 1 and 17 with type 2 diabetes who were investigated. Sympathetic nerve function was assessed by measurement of the vasoconstriction (VAC) index by laser Doppler perfusion imaging of a locally heated finger followed by indirect cooling. Parasympathetic nerve function was assessed by R-R interval variation during deep breathing as measured by the expiration/inspiration (E/I) ratio. Results were expressed as age-corrected z scores in SD; VAC index >1.64 SD and E/I ratio <−1.64 SD were considered abnormal. RESULTS—VAC index was abnormal in 40% with type 1 and 41% with type 2 diabetes, whereas the E/I ratio was abnormal in 42% with type 1 and 65% with type 2 diabetes. There was a clear association between VAC index and E/I ratio among type 1 (rs = 0.525; P = 0.0002) but not among type 2 (rs = 0.10) diabetic patients. Among type 2 diabetic patients, the degree of dysfunction was most severe regarding parasympathetic function (P = 0.0167). CONCLUSIONS—Sympathetic and parasympathetic neuropathy were frequent in both type 1 and type 2 diabetic patients. However, there was a difference between the two types of diabetes. Sympathetic and parasympathetic nerve functions correlated in type 1 but not in type 2 diabetic patients. The explanation for this discrepancy might be that parasympathetic nerve function was most severely affected among type 2 diabetic patients.
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| 4. |
- Freccero, Carolin, et al.
(författare)
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The influence of wavelength and probe configuration on findings of a skin vasoconstriction test when using laser Doppler perfusion devices.
- 2006
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Ingår i: Microvascular Research. - : Elsevier BV. - 1095-9319 .- 0026-2862. ; 71:Jan 3, s. 64-67
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to establish the degree to which a standardized test based on laser Doppler blood flow measurement is dependent on the particular equipment set-up being used. For this purpose, we examined finger skin blood flow with laser Doppler instruments in 20 healthy subjects. In laser Doppler perfusion monitoring (LDPM), we used a custom-made probe with two detecting fibers placed 0.25 and 1.2 min from the illuminating fiber, respectively, and two laser Doppler perfusion imagers (LDPI) with a wavelength of 632.8 nm and 780 rim, respectively. Warming of the hand was achieved with a Peltier element, and reflex vasoconstriction was induced by immersing the other hand for 3 min into a water bath kept at 15 degrees C. As a measure for the change in skin blood flow, a vasoconstriction index (VAC: cooling/before cooling) was calculated and used for the comparison of the different devices. VAC values gathered around 0.6 for all devices. However, LDPI with a wavelength of 632.9 nm showed a slightly higher VAC index, and the difference was significant. We conclude that using a standardized test is the most appropriate for monitoring changes in blood flow rather than recording and comparing discrete values in intermittent recordings. Although a difference was noted when comparing the devices, different fiber separations and wavelengths seem then to be of little consequence. (c) 2005 Published by Elsevier Inc.
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| 5. |
- Holmlund, F, et al.
(författare)
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Sympathetic skin vasoconstriction--further evaluation using laser Doppler techniques
- 2001
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Ingår i: Clinical Physiology. - : Wiley. - 1365-2281 .- 0144-5979. ; 21:3, s. 287-291
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to quantify the reflex sympathetic vasoconstriction in skin at different depths. Twenty healthy subjects were studied. Finger skin blood flow was measured using laser Doppler perfusion imaging (LDPI) and laser Doppler perfusion monitoring (LDPM). In LDPM, a probe with fibres separated 0.25 mm (deep) and 0.14 mm (superficial) from the illuminating fibre was used. Local heating (40 degrees C) was achieved with a Peltier element, and reflex vasoconstriction induced by immersion of the contra-lateral hand and forearm for 3 min in water at 15 degrees C. The change in skin blood flow was measured and a vasoconstriction index (VAC: cooling/before cooling) calculated. VAC indices of LDPI, LDPM-0.25 and LDPM-0.14 were 0.60, 0.59 and 0.60, respectively. The two components of the LDPM perfusion value, blood cell velocity and concentration, were studied separately. Their contributions in LDPM-0.25 were roughly the same, whereas the velocity component dominated in LDPM-0.14, although their relative responses in the two channels were similar. We conclude that sympathetic skin vasoconstriction does not significantly differ in two compartments, as probed with fibres separated by 0.25 and 0.14 mm. Blood cell velocity is influenced in a proportional way, as is concentration.
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| 6. |
- Rydén Ahlgren, Åsa, et al.
(författare)
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Increased aortic stiffness in women with type 1 diabetes mellitus is associated with diabetes duration and autonomic nerve function
- 1999
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Ingår i: Diabetic Medicine. - 1464-5491. ; 16:4, s. 291-297
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: The increase in risk for cardiovascular complications in diabetic women is even greater than that in diabetic men. We found arterial stiffness to be increased in women, but not in men, with Type 1 diabetes mellitus (DM). The aims of the present study were to evaluate whether the changes in arterial distensibility are influenced by diabetes duration and to evaluate any association between autonomic neuropathy and decreased arterial distensibility. METHODS: Stiffness of the abdominal aorta was measured noninvasively using echo-tracking sonography and parasympathetic function by heart rate variation during deep breathing (E/I ratio) in 40 women (mean age 33 years, range 20-61) and 38 men (mean age 36 years, range 22-56) with Type 1 DM. RESULTS: There was a significant correlation between aortic stiffness and duration of diabetes in women (r = 0.41, P = 0.008), but not in men (r = 0.15, P = 0.35). There was also a significant correlation between aortic stiffness and the E/I ratio in women (r = -0.49, P = 0.002), but not in men (r = -0.14, P = 0.41). When adjusted for diabetes duration, the significant association between the E/I ratio and aortic stiffness remained in diabetic women (r = -0.44, P = 0.008) and was stronger than the association between diabetes duration and aortic stiffness. There were no significant correlations between aortic stiffness and triglycerides or total cholesterol, respectively. CONCLUSIONS: Increased aortic wall stiffness found in women with Type 1 DM is related to diabetes duration. Further, in women with Type 1 DM there is a correlation between increased aortic stiffness and parasympathetic dysfunction. This may be of importance for the increased susceptibility to cardiovascular complications in diabetic women.
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| 7. |
- Rydén Ahlgren, Åsa, et al.
(författare)
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Increased arterial stiffness in women, but not in men, with IDDM
- 1995
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Ingår i: Diabetologia. - 1432-0428. ; 38:9, s. 1082-1089
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Tidskriftsartikel (refereegranskat)abstract
- For unknown reasons, there is a greater increase in the risk for cardiovascular complications in diabetic women than in diabetic men. Our aim was to study gender-related differences in the mechanical properties of the great arteries in patients with insulin-dependent diabetes mellitus (IDDM) but free from known cardiovascular and cerebrovascular complications. We measured arterial stiffness (beta, inversely related to arterial compliance) in the abdominal aorta and the common carotid artery non-invasively using echo-tracking sonography in 30 women (mean age 34 years, range 20-61) and 26 men (mean age 38 years, range 22-56) with IDDM. The results were compared with those of healthy individuals of corresponding age and gender. The results showed a marked gender-difference in changes of arterial stiffness. Arterial stiffness was increased in both the abdominal aorta and the common carotid artery in diabetic women compared to control women (p = 0.0001 and p = 0.0076, respectively). In contrast, there was no significant difference in stiffness of the abdominal aorta or the common carotid artery between the diabetic men and the control men (p = 0.69 and p = 0.39, respectively). In conclusion, this study has shown that stiffness of the aorta and the common carotid artery is increased in diabetic women but not in diabetic men. Increased arterial stiffness in diabetic women may be a pathogenic factor which could help to explain the gender-related differences in the risk for cardiovascular and cerebrovascular complications in diabetic subjects.
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