T-helper 1 and 2 activation with fresh or cultured allo- or xenoislets.
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Animals↗
Biomedical subjects
R Navalesi
Publications and source records attributed to R Navalesi.
Difference in treatment of foot ulcerations in Boston, USA and Pisa, Italy.
Primary care of the diabetic patient with foot ulcer can be provided by medically or surgically trained practitioners. We have prospectively followed 90 sequential patients with newly developed foot ulcers from two major centers. One in the USA where the primary doctor was a podiatrist and one in Europe with a diabetologist. Thirty-four patients from Boston and 56 from Pisa (mean age, 55.6; range, 26-75 years; vs. 66.5; range, 35-94; P < 0.001), matched for sex, weight, type, duration of diabetes, renal impairment and retinopathy took part. Boston patients had more severe neuropathy, assessed with clinical examination utilizing a neuropathy disability score (NDS) (16 +/- 6 vs. 6 +/- 3 (mean +/- S.D.) P < 0.001) and vibration perception threshold (46 +/- 8 vs. 35 +/- 12 V: P < 0.001) while no difference existed in the number of patients with clinical infection, a history of lower extremity by-pass operation (6 (18%) vs. 3 (5%); P = NS) and in the size and the severity of the ulcer, according to the Wagner classification. Initial treatment was similar in both centers with emphasis on outpatient ulcer debridement, pressure relieving foot-wear and topical wound care. Hospitalization was needed in five (15%) Boston and 12 (21%) Pisa patients (P = NS) while surgery was performed on five (15%) Boston and 16 (29%) Pisa patients (P = NS). The in-hospital stay was similar in both centers (1.4 +/- 4.4 vs. 2.1 +/- 5.9 days; P = NS). The most common operations in both centers were incision, drainage and bone debridement. Ulcers healed in all patients but the amount of healing time was shorter in Boston patients (6.7 +/- 4.2 vs. 10.5 +/- 6.5 weeks; P < 0.02). We conclude that despite the differences in the two systems similar success rates were achieved in the two centers while a more surgically oriented strategy may have resulted in a slightly shorter healing time.
Adult↗
Transcapillary escape rate of albumin in type II diabetic patients. The relationship with microalbuminuria and hypertension.
OBJECTIVE: To study why in type II diabetes, microalbuminuria, a marker of generalized vascular dysfunction, and hypertension have been linked with both renal and cardiovascular organ damage. RESEARCH DESIGN AND METHODS: To investigate the effect of moderately elevated blood pressure on vascular damage, the transcapillary escape rate of albumin (TERalb) was measured by intravenous injection of purified 125I-human serum albumin in 9 healthy control subjects (group 1), 9 nondiabetic hypertensive subjects (group 2), and 73 nonobese type II diabetic patients stratified as follows: group 3: 17 normoalbuminuric-normotensive subjects; group 4: 22 normoalbuminuric-hypertensive subjects (systolic blood pressure [sBP] > or = 140 mmHg or diastolic blood pressure [dBP] > or = mmHg or both); group 5: 16 normotensive subjects with microalbuminuria (albumin excretion rate [AER]: 20-200 micrograms/min); and group 6: 18 microalbuminuric-hypertensive subjects. RESULTS: Groups 3-6 had similar age, sex, duration of diabetes (group 3: 7.8 +/- 5.5; group 4: 9.7 +/- 8.7; group 5: 12.1 +/- 8.1; and group 6: 10.7 +/- 8.3 years), BMI, HbA1c (7.8 +/- 1.1, 7.5 +/- 1.5, 8.7 +/- 1.5, and 7.7 +/- 1.1%, respectively), blood glucose, and lipid profile. Systolic and diastolic blood pressure did not differ in the three hypertensive group (group 2: 154 +/- 3/99 +/- 6; group 4: 149 +/- 13/95 +/- 6; group 6: 154 +/- 15/91 +/- 9 mmHg) and were significantly lower (P < 0.001) in group 3 (126 +/- 12/76 +/- 7), group 5 (128 +/- 11/77 +/- 5), and healthy control subjects (group 1: 133 +/- 7/81 +/- 4). TERalb was similar in control subjects (5.77 +/- 1.06%/h) and in normoalbuminuric-normotensive subjects (5.81 +/- 1.51%/h) but significantly higher (P < 0.0001) in microalbuminuric subjects with or without hypertension (9.11 +/- 1.65 and 8.60 +/- 1.50%/h, respectively) as well as in normoalbuminuric diabetic patients with hypertension (8.10 +/- 2.27%/h) and in essential hypertensive subjects (8.12 +/- 1.68%/h). CONCLUSIONS: By stepwise regression, TERalb was related (step 1) to log-AER (r = 0.30) or to the presence of microalbuminuria (r = 0.36) and (step 2) to dBP (multiple r = 0.40) or to the presence of hypertension (multiple r = 0.51) in the whole diabetic cohort (groups 3-6). TERalb was related to dBP (r = 0.47) or to the presence of hypertension (r = 0.56) only in normoalbuminuric diabetic patients (groups 3 and 4) and to log-AER (r = 0.56) or the presence of microalbuminuria (r = 0.68) only in normotensive patients (groups 3 and 5). In type II diabetic patients, TERalb was elevated in subjects with increased albuminuria, irrespective of blood pressure levels, but also was independently related to the presence of mild-to-moderate systemic hypertension.
Adult↗
A natural apolipoprotein A-I variant, apoA-I (L141R)Pisa, interferes with the formation of alpha-high density lipoproteins (HDL) but not with the formation of pre beta 1-HDL and influences efflux of cholesterol into plasma.
ApoA-I(L141R)Pisa is a naturally occurring apolipoprotein A-I variant that causes virtual absence of HDL in hemizygotes and hypoalphalipoproteinemia with half-normal levels of HDL-cholesterol in heterozygotes. In this study we analyzed the distribution of HDL subclasses in plasmas of four hemizygotes for this mutation. We also investigated the abilities of these plasmas to esterify cholesterol and to promote cholesterol efflux. Residual apoA-I-containing lipoproteins in plasmas of hemizygotes for apoA-I(L141R)Pisa correspond to pre beta 1-LpA-I and small alpha-LpA-I. Unlike normal pre beta 1-LpA-I, pre beta 1-LpA-I of apoA-I(L141R)Pisa hemizygotes was not converted into a larger alpha-migrating particle. Plasmas of apoA-I(L141R)Pisa hemizygotes were significantly reduced in their activity to esterify cholesterol in either endogenous or exogenous lipoproteins. Cholesterol efflux capacity was significantly lower than that of normal plasma. Efflux of [3H] cholesterol from radiolabeled fibroblasts into apoB-depleted plasma of normal probands was biphasic with fast cholesterol efflux occurring in the first minute. Thereafter, cholesterol efflux was slow and unsaturable. After incubation with radiolabeled fibroblasts, efflux values of [3H]cholesterol into apoB-depleted plasma from normal controls and from apoA-I(L141R)Pisa hemizygotes were indistinguishable at 1 min. Longer incubations with apoB-free plasma from apoA-I(L141R)Pisa hemizygotes did not, however, lead to the unsaturable increase in cholesterol efflux that was observed during incubations with apoB-free plasma of normolipidemic probands. Pre beta 1-LpA-I of apoA-I(L141R)Pisa hemizygotes took up significantly less cell-derived [3H]cholesterol than pre beta 1-LpA-I of normal donors. We conclude that apoA-I(L141R)Pisa interferes with the formation of lipid-rich alpha-HDL but not with that of lipid-poor pre beta 1-LpA-I. Very low concentrations of alpha-HDL in plasmas of apoA-I(L141R)Pisa hemizygotes combined with reduced LCAT activity cause a decrease of the slow, unspecific, and LCAT-dependent components of cholesterol efflux into plasma.
Animals↗
Screening of gestational diabetes in Tuscany: results in 2000 cases.
According to the guidelines of the "Third international workshop conference on GDM", we have examined 2000 pregnant women. The glucose challenge test (GCT) was positive in 408 cases (20.4%) and negative in 1592 (79.6%). The OGTT (Carpenter and Coustan's criteria) was performed in 647 pregnant women. GDM and IGGT prevalence was of 6.25% and 5.5% respectively and normal glucose tolerance (NGT) 88.25%. The GCT effectiveness for GDM and IGGT diagnosis is: sensibility 75.1%, specificity 44%, positive predictive value 46.4% and negative predictive value 74%. GDM and IGGT compared with NGT women were significantly older (p < 0.05) and prepregnancy BMI was higher (p < 0.01); the prevalence of previous macrosomia (p < 0.01), previous gestational diabetes (p < 0.01) and family history for diabetes mellitus (p < 0.05) was greater in GDM and IGCT. The prevalence of preterm delivery was higher in both GDM and IGCT (GDM 12.5% and IGGT 15.4% vs NGT 6%; p < 0.01), as well as the prevalence of cesarean sections (GDM 31.6% vs IGGT 23.5% and NGT 20.3%; p < 0.02), and the occurrence of macrosomia (GDM 27.6%, IGGT 16.6% and NGT 16.2%). In addition a higher prevalence (p < 0.01) of hyperbilirubinaemia, hypoglycemia and hypertrophy cardiomyopathy was observed in newborns from GDM women. Our data show that: GCT has a good specificity for GDM diagnosis, prevalence of GDM in our population is about 6%, GDM is still correlated to an elevated maternal and neonatal morbility.
Adult↗
Gestational diabetes: clinical characteristics and birth weight.
This retrospective study investigates the clinical characteristics of gestational diabetes mellitus (GDM) (time of diagnosis, different treatment, metabolic parameters, etc.) in relation to prepregnancy body mass index (BMI) and the influence of BMI on neonatal outcome. 93 GDM women and 110 control subjects were divided into three groups in relation to their prepregnancy BMI: normalweight (Nw), overweight (Ow) and obese (Ob). GDM was diagnosed significantly (p < 0.01) earlier in Ow and Ob than in Nw. Preterm deliveries and cesarean sections resulted significantly (p < 0.01) increased in all BMI categories of GDM respect to matched controls. Prevalence of neonatal macrosomia was higher in GDM patients (44.6%) compared with normal controls (15.4%) and correlated (p < 0.01) with prepregnancy BMI in both groups. Nevertheless in each BMI category the prevalence of macrosomia was significantly higher in GDM patients. The body weight increase during pregnancy was not associated with neonatal macrosomia. This study shows that prepregnancy BMI is an important risk factor for GDM and is predictive for macrosomia specially in women suffering from GDM.
Adult↗
Compound heterozygosity for a structural apolipoprotein A-I variant, apo A-I(L141R)Pisa, and an apolipoprotein A-I null allele in patients with absence of HDL cholesterol, corneal opacifications, and coronary heart disease.
BACKGROUND: The concentration of HDL cholesterol is inversely correlated with the risk of coronary heart disease (CHD). Some rare mutations in the apolipoprotein (apo) A-I gene are associated with low levels of HDL cholesterol. Their association with cardiovascular risk is controversial. METHODS AND RESULTS: We studied the molecular defects underlying corneal opacities and absence of HDL cholesterol in three brothers and a sister. In a family study, the importance of these defects for lipid metabolism and manifestation of coronary heart disease was investigated. The frequency of these apo A-I defects was assessed by genotype and phenotype analysis of 477 DNA- and plasma samples, respectively, from the population. The four patients were compound heterozygotes for a null allele and a missense mutation in the apo A-I gene that leads to a leucine-->arginine substitution at residue 141 [apo A-I(L141R)Pisa]. Heterozygotes for either the null allele or the structural variant had half-normal concentrations of HDL cholesterol and apo A-I compared with unaffected family members. Apo A-I(L141R)Pisa was detected in one more unrelated subject. Coronary angiography of the four compound heterozygotes revealed the presence of CHD in all male patients, whose ages ranged between 45 and 52 years. They presented with additional risk factors, including elevated LDL cholesterol levels, obesity, and arterial hypertension. Despite complete HDL deficiency and hypercholesterolemia, CHD was absent in the 51-year-old premenopausal sister. CONCLUSIONS: Apo A-I deficiency may lead to premature atherosclerosis if present in conjunction with additional cardiovascular risk factors.
Adolescent↗
Characterization of peripheral benzodiazepine receptors in purified large mammal pancreatic islets.
In this work, we evaluated the biochemical properties of peripheral benzodiazepine receptors (PBRs) in the porcine endocrine pancreas and their role in insulin release. Binding of [3H]1-(2-chlorophenyl-N-methyl-1-methyl-propyl)-3-isoquinolinecarboxa mide ([3H]PK-11195), a specific ligand of PBRs, to islet membranes was saturable and Scatchard's analysis of saturation curve demonstrated the presence of a single population of binding sites, with a dissociation constant (Kd) value of 4.75 +/- 0.70 nM and a maximum amount of specifically bound ligand (Bmax) of 4505 +/- 502 fmol/mg of proteins. The pharmacological profile of PBRs was determined as the ability of PK-11195 and several benzodiazepine compounds to displace [3H]PK-11195 from these binding sites. The rank order of potency yielded the following affinity results: PK-11195 > 7-chloro-1,3-dihydro-1-methyl-5-(p-chlorophenyl)-2H-1,4-benzodiazepine-2 -on (Ro 5-4864) > diazepam > or = flunitrazepam >> flumazenil. Secretion studies demonstrated that PK-11195 (1 and 10 microM) and Ro 5-4864 (10 and 50 microM) significantly potentiated insulin secretion from freshly isolated porcine islets at 3.3 mM glucose. This potentiating effect was not observed at 16.7 mM glucose concentration nor by the addition of clonazepam. These results show the presence of PBRs in purified porcine pancreatic islets and suggest an implication of PBRs in the mechanisms of insulin release.
Animals↗
Prolonged survival of discordant porcine islet xenografts.
Purified porcine islets were prepared by collagenase digestion and density gradient purification, and transplanted under the kidney capsule of C57B/B6 mice with streptozotocin-induced diabetes which were receiving varying temporary immunosuppressive therapies. Islets that had been cultured for 1 day at 37 degree C were rejected after : 9+/-0.1 (mean+/-SE) days in control mice: 14+/-3 days in mice receiving mouse antilymphocyte serum (MLS) plus porcine antilymphocyte serum (PLS) on day of transplant (day 0); 43+/-6 days in mice treated for 1 week with anti-CD4 antibody (aCD4); 36+/-4 days in mice given aCD4 for 1 week plus PLS on days 0 and 7; 47+/-3 days in mice treated with aCD4 for 1 week plus MLS and PLS on day 21. Porcine islet survival in these latter three groups was significantly (P<0.01) and similarly longer than in the control and MLS plus PLS groups. Then, we transplanted islets that had been either cultured at 24 degrees C for 7 days or cryopreserved into 7-day aCD4-treated mice, to evaluate whether low temperature culture or the freezing-thawing procedure could affect survival. Neither 7-day, low temperature culture (mean survival time: 37+/-2 days) nor cryopreservation (mean survival time: 39+/-2 days) prolonged islets function further. Thus, the present study demonstrates that prolonged survival can be achieved with discordant porcine islet xenografts, and shows the greater efficacy of aCD4 treatment, which was not improved by additional immunosuppressive therapies we tested, nor by culture or cryopreservation of the islets.
Animals↗
Lymphokine release during co-culture of human lympho-mononuclear cells and fresh or cultured human, porcine and bovine pancreatic islets.
In this study we evaluated whether isolated human (HI), porcine (PI) and bovine (BI) islets, either fresh (Fr) or cultured for 4 weeks (4 w) affect cytokine release from human lymphomononuclear cells (LMC) differently. We prepared LMC from peripheral blood by density gradient purification and co-cultured 1 x 10(6) LMC for 24 h with 100 hand-picked islets, either within 48 h of isolation or after culture for 4 weeks. Soluble interleukin-2 receptor (IL-2R), interferon-gamma (IFN), interleukin-4 (IL-4) and interleukin-10 (IL-10) were measured by sandwich enzyme-linked immunoadsorbent assay. Compared with controls (Ctrl, LMC without islets), Fr-HI, Fr-PI and Fr-BI caused a similar increase of IL-2R and IFN release, whereas 4 w-HI and 4 w-BI did not lead to any significant production of these two cytokines. IL-10 concentrations increased with Fr-PI and Fr-BI, but not with Fr-HI, and no major effect of the 4-week culture was seen. IL-4 levels were below the detection limit of the method used in these experiments. Thus, fresh allo- and xeno-islets caused a similar increase of the release of cytokines known to be markers of Th1 activation, whereas the release of IL-10, a marker of Th2 activation, increased with xeno-, but not with allo-islets; culturing the islets for 4 weeks decreased Th1, but not Th2 activation.
Animals↗
Long-term survival and function of isolated bovine pancreatic islets maintained in different culture media.
Bovine islets are being evaluated for their potential in transplantation studies. We studied the recovery, morphology, and function of purified bovine islets cultured up to 4 weeks under varying conditions. Approximately 60% of the initial islet mass could be recovered after 4 weeks at 37 degrees C in CMRL 1066 or M 199 culture medium, and the cultured islets were well preserved histologically and viable both in vitro and in vivo. On the other hand, culture with RPMI 1640 caused disaggregation of the islets within a few days, with altered in vitro viability. Thus, culturing purified bovine islets with appropriate media is a suitable procedure to maintain islet mass, morphology, and function in the long term.
Animals↗
Diabetologic in-service education for health professionals from non-diabetological departments.
In order to test whether or not an in-service requalification course on diabetes care for health professionals (HP) of nondiabetological departments can enhance their level of knowledge about diabetes and the quality of care for diabetic inpatients admitted for reasons other than diabetes, we carried out a requalification course involving 171 HP (161 nurses and 10 midwives) from nondiabetological departments of our hospital. Areas of intervention were: general knowledge of diabetes (GKD), bedside monitoring of blood glucose (BMG), insulin preparation and administration (IPA), diagnosis and treatment of hypoglycemic crises (DTH), and hospitalization-related problems (HRP). HP, divided into groups of about 20 each, completed a basal evaluation by means of a 25-item multiple choice questionnaire, and then attended six separate educative sessions, each of focusing on one topic, consisting of a theory lesson and an interactive exercise of equivalent length. At the end of the course, HP were re-evaluated with the same questionnaire, and their skills in BMG, IPA and DTH were tested by means of specific operational checklists, which divided each complex operation into a sequence of single operations, and then compared them with those of a control group of untrained colleagues (CG). The global knowledge of diabetes after the courses significantly improved, as gathered from the percentages of correct answers in each questionnaire (61.82% +/- 23.64% vs 31.18% +/- 20.00%; P < 0.001); separate analysis of different areas evidenced improvements in GKD (72.28% +/- 12.47% vs 31.46% +/- 20.56%; P < 0.01), BMG (68.77% +/- 15.75% vs 37.50% +/- 27.75%; P < 0.01), IPA (72.02% +/- 11.72% vs 33.45% +/- 21.22%; P < 0.05), and DTH (90.76% +/- 6.86% vs 49.82% +/- 26.68%; P < 0.05), but not in HRP. Professional skills profiles of HP, evaluated by measuring the number of errors done performing each task, were significantly (P < 0.001) better than those of CG, for BMG (1.09 +/- 0.73 vs 4.91 +/- 2.01), IPA (2.36 +/- 1.64 vs 5.64 +/- 2.25), and DHT (1.27 +/- 0.94 vs 3.82 +/- 1.12). Linear regression showed a significant (P < 0.001) correlation of skills and knowledge after the course for BMG (r2 = .49), IPA (r2 = .53), and DTH (r2 = .61). Positive although nonspecific indicators of outcomes of the course were the increase (of about 100%) of requests to our metabolic unit for diabetological consultations from other departments as well as the mentioning of diabetes in the diagnosis of discharge, and the 20% increase in the consumption of sticks for BMG. The course produced a significant improvement of knowledge and skills on specific diabetological items among participants.
Diabetes Mellitus↗
Metformin potentiates glucose-stimulated insulin secretion.
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Drug Synergism↗
Neonatal outcome and obstetric complications in women with gestational diabetes: effects of maternal body mass index.
OBJECTIVE: To evaluate in a selected population the clinical characteristics (time of diagnosis, different treatment, metabolic parameters, etc.) of gestational diabetes in relation to prepregnancy body mass index (BMI) and the influence of BMI on neonatal outcome. DESIGN: This study was retrospectively led using a computerized data system for all deliveries that occurred at the Departments of Obstetrics and Gynecology of the University of Pisa (Italy) from 1 January 1987 to 31 December 1992. SUBJECTS: 93 women with GDM and 110 control subjects divided into three groups according to their pre-pregnancy BMI: normal weight (Nw), overweight (Ow) and obese (Ob). MEASUREMENTS: Time of diagnosis, mode of treatment and metabolic control of GDM; time and mode of delivery, neonatal outcome (macrosomia, respiratory distress syndrome, hyperbilirubinemia, hypoglycemia, polycythemia, hypocalcemia). RESULTS: GDM was diagnosed earlier in Ow and Ob than in Nw (p < 0.01) and insulin treatment was used in 86% of Ob-GDM, 91% of Ow-GDM and in 77% of Nw-GDM women (p < 0.001). Preterm deliveries and cesarean sections resulted significantly increased in all BMI categories of GDM patients with respect to matched normal controls. Prevalence of neonatal macrosomia was higher in GDM patients (44.6%) compared with normal controls (15.4%) and correlated (p > 0.01) with prepregnancy BMI in both groups. The body weight increase during pregnancy was not associated with neonatal macrosomia. CONCLUSIONS: The degree of overweight is associated with an earlier diagnosis of GDM; prepregnancy BMI is more predictive of macrosomia than weight gain, both in control and GDM women; GDM seems to play the most important role in increasing the possibility of the occurrence of macrosomia.
Body Mass Index↗
Effects of tryptophan load on amino acid metabolism in type 1 diabetic patients.
Tolerance to an oral tryptophan load (50 mg/kg body weight) was evaluated in a group of 15 insulin-dependent diabetic patients of both sexes in poor metabolic control. Tryptophan was measured fluorometrically, and the plasma levels of the other physiological amino acids were determined by HPLC. The ratio of the plasma concentration of each large neutral amino acid (LNAA) to the sum of the others was calculated to serve as an index for the competitive transport of these amino acids into the brain. The results show that post-loading plasma tryptophan levels in diabetic patients increased less than in healthy controls, suggesting enhanced liver catabolism of this amino acid (as reported for diabetic animals). Small changes were observed in the post-loading plasma concentrations of other amino acids. Therefore, the increment in the tryptophan/LNAA ratio in controls (basal, 0.12 +/- 0.01; 120 min after the load, 0.89 +/- 0.04; 240 min, 0.51 +/- 0.03) was greatly attenuated in diabetic patients (basal, 0.11 +/- 0.01, NS; 120 min, 0.46 +/- 0.04, p < 0.01; 240 min, 0.31 +/- 0.04, p < 0.01). Post-loading excursions in some other ratios were slightly larger in control than diabetic subjects. These differences, which may occur to a lesser extent after a protein-rich meal, could modify the availability of precursor amino acids to the brain for synthesis of neurotransmitters. Thus, as happens in certain animal species, an impairment of the post-absorptive accumulation of tryptophan and serotonin in the brain may occur in diabetic patients as a result of altered metabolic disposal of tryptophan.
Adult↗
Cryopreservation of purified bovine islets of Langerhans.
In this study, bovine islets were isolated by collagenase digestion and density gradient purification, equilibrated stepwise with 3 M dimethylsulfoxide at 24 degrees C, nucleated at -150 degrees C, slow cooled at 0.25 degrees C/min down to -40 degrees C, and finally stored at -150 degrees C. After variable periods of time, the islets were quickly thawed at 37 degrees C, and dimethylsulfoxide was removed by 0.75 M sucrose. Postthawing recovery was 86 +/- 6% islet equivalents. Histology confirmed the identity and morphological integrity of the islets. Insulin release from the frozen-thawed islets was 0.13 +/- 0.03 microU/is/min at 3.3 mmol/L glucose and increased significantly (0.27 +/- 0.04 microU/is/min, P < 0.05) at 25 mmol/L glucose. Encapsulated, cryopreserved islets reversed hyperglycemia in diabetic mice after 6-8 days following implantation. Therefore, the method described in this paper permitted successful cryopreservation of bovine islets of proven in vitro and in vivo viability.
Animals↗
Genetically determined absence of HDL-cholesterol and coronary atherosclerosis.
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Aged↗
Blood pressure, retinopathy and urinary albumin excretion in IDDM: the EURODIAB IDDM Complications Study.
Several studies have shown an association between blood pressure and nephropathy, but few have been large enough to examine whether, or how, this relation is influenced by retinopathy. We have therefore examined the independent relations of blood pressure to urinary albumin excretion and retinopathy in a cross-sectional observational study of over 3000 insulin-dependent diabetic patients (the EURODIAB IDDM Complications Study). The relation of blood pressure to urinary albumin excretion differed strikingly between patients with (46%) and without (54%) retinopathy. In those with retinopathy, mean urinary albumin excretion rate was normal (< 20 micrograms/min) below median diastolic pressure (75 mmHg) and increased steeply (p < 0.001) with blood pressure above this level. However, in patients without retinopathy, mean albumin excretion rate was normal across the range of diastolic pressure. This finding could not be explained by differences in glycaemic control or duration of diabetes between patients with and without retinopathy. These data identify a subgroup of patients whose high risk of nephropathy may reflect abnormal renal vulnerability to mildly raised blood pressure. Retinopathy is a close correlate of this vulnerability. Detection of even mild retinopathy, together with raised blood pressure, may be important in assessing nephropathy risk.
Adult↗