| 1. |
- Agardh, Elisabet, et al.
(författare)
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A 5-year follow-up study on the incidence of retinopathy in type 1 diabetes mellitus in relation to medical risk indicators
- 1994
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Ingår i: Journal of Internal Medicine. - 1365-2796. ; 235:4, s. 353-358
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES. The aim of the present study was to describe the 5-year incidence of retinopathy in type 1 diabetes mellitus and to characterize risk indicators for the development and progression of retinopathy. DESIGN. A cross-sectional study of type 1 diabetic patients taken care of at a medical department. SETTING. All type 1 diabetic patients attending the Department of Internal Medicine, University Hospital, Lund, during a 2-year period were offered ophthalmological examination. SUBJECTS. A total of 396 out of 461 (85.9%) initially examined type 1 diabetic patients formed the basis for this 5-year follow-up study. MAIN OUTCOME MEASURES. The degree of retinopathy was based on fundus photography or biomicroscopy. Degree of metabolic control was assessed by HbA1c levels, signs of nephropathy by albumin creatinine clearance ratio and urinary albumin levels. Blood pressure was measured in the supine position. Duration of diabetes, age, and insulin dosage were registered. RESULTS. The incidence of retinopathy was 47.2% and progression from background to severe retinopathy occurred in 41%. Risk indicators for the development of retinopathy were duration of diabetes (P < 0.001), degree of metabolic control (P < 0.001), insulin dosage (P < 0.05) and signs of nephropathy based on measurements of albumin creatinine clearance ratio (P < 0.01) and urinary albumin concentration (P < 0.05). Two risk indicators could be identified for progression of retinopathy, i.e. the degree of metabolic control (P < 0.01) and diastolic blood pressure (P < 0.05). CONCLUSIONS. The results suggest that apart from poor metabolic control, development of retinopathy in type 1 diabetes is associated with long diabetes duration and clinical signs of diabetic nephropathy. Progression of retinopathy is associated with poor metabolic control and elevated diastolic blood pressure levels.
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| 2. |
- Torffvit, Ole, et al.
(författare)
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Albuminuria and associated medical risk factors: a cross-sectional study in 451 type II (noninsulin-dependent) diabetic patients. Part 2
- 1991
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Ingår i: Journal of Diabetic Complications. - 0891-6632. ; 5:1, s. 29-34
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Tidskriftsartikel (refereegranskat)abstract
- The association between urinary albumin concentration (UAC) in a morning urine sample and medical risk factors was evaluated in a cross-sectional study of 451 type II (noninsulin-dependent) diabetic patients. The following four groups of patients were created according to their urinary albumin levels: A) normal (less than 12.5 mg/L); B) high normal (12.5-30 mg/L); C) microalbuminuria, ie, incipient nephropathy (31-299 mg/L); and D) clinical nephropathy (greater than or equal to 300 mg/L). The patients with high normal levels had higher HbA1c and systolic blood pressure levels than patients with values within normal limits. The prevalence of incipient and clinical diabetic nephropathy was 20 and 7%, respectively. Incipient nephropathy was associated with higher blood pressures and body weights. Patients with clinical nephropathy had even further increases in these parameters, were older, and had longer duration of diabetes. In both groups of nephropathy, men were preponderant. Thirty six percent of all patients and 73% of patients with clinical nephropathy were treated for hypertension; 55% were treated with insulin. The insulin-treated patients had poorer metabolic control, but there were no differences in blood pressure or serum creatinine levels as compared with those of patients not receiving insulin treatment. The proportion of patients with severe retinopathy increased with the degree of albuminuria, although 22% of the patients with clinical nephropathy continued to be nonretinopathic.
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| 3. |
- Torffvit, Ole, et al.
(författare)
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Albuminuria and associated medical risk factors: a cross-sectional study in 476 type I (insulin-dependent) diabetic patients. Part 1
- 1991
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Ingår i: Journal of Diabetic Complications. - 0891-6632. ; 5:1, s. 23-28
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Tidskriftsartikel (refereegranskat)abstract
- Albumin concentration in a morning urine sample was analyzed in a cross-sectional study in 476 insulin-dependent diabetic patients. The following groups of patients were defined: A) normal urinary albumin (urine albumin less than 12.5 mg/L); B) high normal albuminuria (12.5-30 mg/L); C) microalbuminuria, ie, incipient nephropathy (31-299 mg/L); and D) clinical nephropathy (greater than or equal to 300 mg/L). The prevalences of incipient and clinical diabetic nephropathy were 24.8 and 14.4%, respectively. There were no differences in clinical parameters such as age, age at onset or duration of diabetes, blood pressure, serum creatinine, or HbA1c levels between groups A and B. The frequency of retinopathy in these groups was 55 and 50%, respectively. In group C, there were increases in age, duration of diabetes, blood pressure, serum creatinine, and HbA1c levels. The frequency of retinopathy was higher (80%), and more patients had severe forms (47%). In group D, there were further increases in all parameters and, in addition, younger age at onset of diabetes. The frequency of retinopathy was 97%, and severe forms of retinopathy were more common (86%). Seventeen percent of the patients were treated for hypertension. These patients were older, had longer duration of diabetes, and had higher levels of blood pressure, serum creatinine, and urinary albumin, as well as a younger age at onset of diabetes than patients not requiring antihypertensive treatment.
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| 4. |
- Agardh, Carl-David, et al.
(författare)
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Growth hormone levels in the basal state and after thyrotropin-releasing hormone stimulation in young type 1 (insulin-dependent) diabetic patients with severe retinopathy
- 1992
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Ingår i: Diabetes Research (Edinburgh, Scotland). - 0265-5985. ; 19:2, s. 81-85
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Tidskriftsartikel (refereegranskat)abstract
- Sixteen young patients with type 1 diabetes mellitus and rapidly progressive severe retinopathy were examined regarding serum levels of growth hormone before and after the i.v. administration of 200 micrograms thyrotropin-releasing hormone (TRH). Serum IGF I, HbA1c, blood pressure, urinary albumin, and serum creatinine levels were also measured. The control group consisted of type 1 diabetic patients matched for age, duration of diabetes and metabolic control with no or minimal background retinopathy. The results show that basal growth hormone levels were above normal in both groups, and that there was a paradoxical increment in growth hormone levels after TRH stimulation (p < 0.05) in patients with severe retinopathy, but the values did not differ from patients with background retinopathy. IGD I levels were normal in all patients but one, and no differences were seen between the two groups. HbA1c, serum creatine, blood pressure, and urinary albumin levels were similar in the groups but patients with severe retinopathy were treated with more insulin (p < 0.001). Thus, neither abnormal growth hormone levels, nor IGF I, seems to be associated with the development of severe retinopathy in young type 1 diabetic patients.
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| 5. |
- Hultberg, Björn, et al.
(författare)
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Poor metabolic control, early age at onset, and marginal folate deficiency are associated with increasing levels of plasma homocysteine in insulin-dependent diabetes mellitus. A five-year follow-up study
- 1997
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Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - 1502-7686. ; 57:7, s. 595-600
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Tidskriftsartikel (refereegranskat)abstract
- In a previous study, we showed that diabetic patients exhibited significantly increased concentrations of total plasma homocysteine (tHcy), but not until the onset of nephropathy. It was suggested that the hyperhomocysteinaemia might contribute to the accelerated atherosclerotic process in diabetic patients. In the present study, we have analysed the main determinants of plasma homocysteine (i.e. serum cobalamin, blood folate and serum creatinine), and also some other parameters related to diabetes mellitus, such as medical history, metabolic and renal quantities, on two occasions with a 5-year interval in 50 patients with insulin-dependent diabetes mellitus, in order to further elucidate the relation between plasma tHcy and diabetes mellitus. The result of the present study shows that diabetic patients with the lowest age at onset and with the poorest metabolic control are those most prone to a rapid increase in plasma tHcy concentration. The increment in plasma tHcy concentration in this group of patients may at least partly be explained by a marginal deficiency of blood folate concentrations.
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| 6. |
- Agardh, Carl-David, et al.
(författare)
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The glutathione levels are reduced in Goto-Kakizaki rat retina, but are not influenced by aminoguanidine treatment
- 1998
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Ingår i: Current Eye Research. - : Informa UK Limited. - 0271-3683 .- 1460-2202. ; 17:3, s. 251-256
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To examine the levels of the free radical protecting enzyme glutathione and the endothelial/pericyte ratio in retinal capillaries in the Goto-Kakizaki (GK) Wistar rat, with and without aminoguanidine treatment. METHODS: Eight-month-old GK rats, with non-obese, spontaneous non-insulin-dependent diabetes mellitus (NIDDM), were examined after a six month period of aminoguanidine treatment. Glutathione levels were measured with high performance liquid chromatography and the endothelial/pericyte ratio was calculated in trypsin digested vessel preparations. RESULTS: The levels of glutathione in GK rat retina were significantly lower compared to controls (p = 0.0108). There was no difference in the endothelial/pericyte ratio compared to matched control rats (1.8 +/- 0.2 vs. 1.8 +/- 0.1, respectively). Aminoguanidine treatment did not influence either the degree of hyperglycemia, the levels of glutathione or the endothelial/pericyte ratio in GK or control rat retina. CONCLUSIONS: The results indicate that impaired glucose metabolism may influence one of the defense mechanisms for oxidative stress, but also suggest that decreased glutathione levels occur prior to morphological signs of pericyte loss and/or endothelial cell proliferation in this animal model of hereditary NIDDM.
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| 7. |
- Agardh, Elisabet, et al.
(författare)
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The importance of early diagnosis of treatable diabetic retinopathy for the four-year visual outcome in older-onset diabetes mellitus
- 1996
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Ingår i: Acta Ophthalmologica Scandinavica. - 1395-3907. ; 74:2, s. 166-170
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Tidskriftsartikel (refereegranskat)abstract
- The four-year visual outcome was retrospectively studied in patients with older-onset diabetes mellitus and diabetic retinopathy in need of laser treatment. Visual acuity in 53 patients examined by ophthalmologists who referred the patients for an evaluation of retinopathy before laser treatment, was compared to that of 47 patients examined by ophthalmologists who also performed the photocoagulation. The number of eyes that became blind (visual acuity < or = 6/60) during the four-year period was higher (23/90 vs 9/91; p < 0.01) among referred patients, whereas the number of retinal examinations per patient during the three-year period prior to laser treatment did not differ between the two groups. Among referred patients, 13% had not been ophthalmologically examined before the treatment-requiring retinopathy was found. Corresponding figure for those examined at the laser centre was 23%. Severe macular oedema in regularly examined patients was more common among referred patients (9/30 vs 1/32; p < 0.01). The results indicate that screening for diabetic retinopathy in older-onset diabetes was not performed satisfactorily. In addition, laser treatment was delayed in older-onset diabetic patients controlled by ophthalmologists who referred patients for photocoagulation, resulting in an increased incidence of legally blind eyes. The study also stresses the importance of carrying out knowledge of when and how to diagnose early sight-threatening diabetic retinopathy to ophthalmologists referring patients for laser treatment.
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| 8. |
- Hansson-Lundblad, C, et al.
(författare)
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Retinal examination intervals in diabetic patients on diet treatment only
- 1997
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Ingår i: Acta Ophthalmologica Scandinavica. - 1395-3907. ; 75:3, s. 244-248
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of the present study was to examine whether type 2 diabetic patients with good metabolic control achieved on diet treatment only, developed sight-threatening retinopathy during a four-year follow-up period. METHODS: A retrospective four-year follow-up study was carried out including all diabetic patients on diet treatment only, registered at the out-patient clinic at the Department of Medicine and referred for fundus photography to the Department of Ophthalmology in 1989 as well as all patients referred from primary care units for fundus photography during 1988 and 1989. One hundred and seventeen diabetic patients treated with diet only were examined with fundus photography after remittance, and after two and four years. RESULTS: Age at diabetes diagnosis was 58.8 +/- 13.8 years (mean +/- SD), age at baseline was 61.5 +/- 13.6 years, and diabetes duration was 2.7 +/- 3.1 years. During the four-year follow-up period, 48 of the patients (41%) remained on diet treatment only whereas diabetes treatment was changed in 66 (56%), from diet to oral agents only in 57 (49%), and from diet to insulin alone or in combination with oral agents in 9 (8%) of the patients. One hundred and six patients (91%) did not have any retinopathy at baseline and 11 patients (9%) had minimal background retinopathy. At follow-up, there were no signs of retinopathy in 93 patients (79%), 22 (19%) had minimal background retinopathy, and two had developed moderate background retinopathy. Out of those patients who were still on diet at follow-up, five (10%) had developed minimal background retinopathy. Mean blood glucose and HbA1c levels, registered every year during the observation period, were higher at most time points in patients who received oral agents or insulin treatment compared to those who were treated with diet only during the entire observation period. No differences were observed between patients who received oral agents and those who received insulin alone or in combination with oral agents. CONCLUSION: It is suggested, that if the initial retinal examination reveals no or minimal diabetic retinopathy at the time of diagnosis of type 2 diabetes mellitus, the second examination can be postponed at least 4 years in patients with good metabolic control on diet treatment only.
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| 9. |
- Zhang, Hui, et al.
(författare)
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Increased catalase levels and hypoxanthine-enhanced nitro-blue tetrazolium staining in rat retina after ischemia followed by recirculation
- 1995
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Ingår i: Current Eye Research. - : Informa UK Limited. - 0271-3683 .- 1460-2202. ; 14:1, s. 47-54
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, using retinal ischemia as a model, we examined if different periods of ischemia and recirculation influenced the generation of reactive oxygen species, i.e. in hydrogen peroxide generation and nitroblue tetrazolium (NBT) reduction. Ischemia was induced for 30 and 90 min by ligation of the optic nerve with the vessels and recirculation was established by removing the ligature. The rats were sacrificed after 15 min or 3 days of recirculation. The retinas were separated from the pigment epithelium for measurements of catalase activity and examination of NBT staining. Compared to controls, the catalase activity was increased after 30 and 90 min of ischemia followed by 15 min of recirculation, and after 90 min of ischemia followed by 3 days of recirculation. As in controls, NBT staining was observed, both after 30 and 90 min of ischemia followed by 15 min of recirculation, in photoreceptors, in both plexiform layers, in some ganglion and glial cells, and, occasionally, in cells in the inner nuclear layer. Opposite to controls, addition of hypoxanthine to the NBT solution resulted in an increased staining in vessels in the inner nuclear layer in retinas subjected to 30 min of ischemia followed by 3 days of recirculation. The increased catalase activity suggests an increased amount of this free radical scavenger after ischemia followed by short-term and long-term recirculation. The hypoxanthine-enhanced NBT staining of blood vessel walls after ischemia followed by long-term recirculation indicates an activation of xanthine oxidase and an increased production of NBT reductants, some of which may represent oxygen free radicals.
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| 10. |
- Zhang, Hui, et al.
(författare)
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Nitro blue tetrazolium staining: a morphological demonstration of superoxide in the rat retina
- 1993
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Ingår i: Graefe's Archive for Clinical and Experimental Ophthalmology. - 1435-702X. ; 231:3, s. 178-183
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Tidskriftsartikel (refereegranskat)abstract
- Nitro blue tetrazolium (NBT) is an artificial electron acceptor which has been suggested to be a useful tool in studies of free radicals. To establish whether NBT could be useful in morphological demonstration of free radicals in the retina, the staining pattern was examined in normal rat retina and after incubation with the free radical scavenger superoxide dismutase or with inhibitors of free radical protective enzymes, such as potassium cyanide, dicoumarol, and aminotriazole. After 60 min incubation in 1 mM NBT, staining was observed in photoreceptors, in some cells in the inner nuclear and ganglion cell layers, and in glial cells. Staining also appeared in the plexiform layers and occasionally in small blood vessels. Addition of superoxide dismutase caused a decreased staining of the inner parts of the retina. The inhibitors of free radical scavengers caused a dose-dependent increase in staining of the inner parts of the retina and, at high concentrations of potassium cyanide, of the photoreceptors. Thus, NBT seems indeed to be useful in morphological studies of free radicals in the retina.
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