Causes of death and risk factors in young and old diabetic patients referred to a retinopathy clinic.

The causes of death and associated risk factors are compared in young and old diabetic patients attending a retinopathy clinic. Mortality in those diagnosed under and over the age of 30 years is also examined in order to compare insulin-dependent with non-insulin-dependent patients. A defined cohort attending the Hammersmith Hospital Retinopathy Clinic was followed for an average of 11 years.

Cigarette smoking: profiles of thromboxane- and prostacyclin-derived products in human urine.

Thromboxane (TX) B2, 2,3-dinor-TXB2, 11-dehydro-TXB2, 6-oxoprostaglandin (PG)F1 alpha and 2,3-dinor-6-oxo-PGF1 alpha were measured in 24 h urine samples obtained from 30 apparently healthy chronic cigarette smokers and 37 closely matched non-smoking control subjects. Samples were analysed using a newly developed assay based on immunoaffinity chromatography and capillary column gas chromatography/electron capture negative ion chemical ionisation mass spectrometry. There were significant and comparable increases in the excretion rates of both 2,3-dinor-TXB2 and 11-dehydro-TXB2 in the smoking compared with the non-smoking group (2P less than 0.

Does vitreous fluorophotometry reflect severity of early diabetic retinopathy?

To determine the relationship between vitreous fluorophotometry (VF) and severity of diabetic retinopathy (DR) 13 patients with mild to moderate background DR starting continuous subcutaneous insulin infusion were followed up serially for 12 months. They were studied by colour stereo retinal photographs, which were assessed by the Wisconsin Grading System, and by VF, which was assessed by the permeability index of the retina for fluorescein. By four months the severity of DR on colour photographs had deteriorated by at least one level in at least one eye in eight patients.

Progression of diabetic retinopathy and changes in serum insulin-like growth factor I (IGF I) during continuous subcutaneous insulin infusion (CSII).

The rise in serum IGF I concentration during continuous subcutaneous insulin infusion (CSII) may be a contributory factor in the deterioration of diabetic retinopathy that sometimes occurs during this treatment but the relation of serum levels to the severity of retinopathy has not been previously studied. In twelve non-obese insulin dependent diabetics (age range: 22-41 yrs) with mean +/- SD duration of diabetes: 14.8 +/- 4.

Diabetic retinopathy: II. Assessment of severity and progression from fluorescein angiograms.

A quantitative method for assessing the severity of retinopathy from fluorescein angiograms was applied to a group of patients starting continuous subcutaneous insulin infusion. There was a highly significant correlation between the area of nonperfusion as measured in the 20 degrees field centered on the right macula, and the mean retinopathy score derived by a standard method from a color retinal photographic survey. In those subjects who deteriorated more, there was an increase in the nonperfused areas, whereas the foveal avascular zone remained unchanged.

Diabetic retinopathy: I. The measurement of intercapillary area in normal retinal angiograms.

A method for the quantitation of areas of non-perfusion of retinal angiograms is described. The values for the area of the foveal avascular zone (FAZ) and the intercapillary areas in the perifoveal region of ten angiograms of normal subjects were determined. The reproducibility of measurement between and within observers was good, correlation coefficients being 0.

Hydroxyethylvaline adduct formation in haemoglobin as a biological monitor of cigarette smoke intake.

The ethylene oxide adduct formed on the N-terminal valine in haemoglobin was investigated as a biological monitor of tobacco smoke intake. The modified method developed for the determination of the hydroxyethylvaline adduct (HOEtVal) involved reaction of globin with pentafluorophenyl isothiocyanate, extraction of the HOEtVal thiohydantoin product, derivatization of this by trimethylsilylation and quantitation by capillary gas chromatography with selective ion monitoring mass spectrometry using a tetradeuterated internal standard. The method was applied to globin samples from 26 habitual cigarette smokers and 24 non-smokers.

The effect of acute hyperglycemia on flow velocity in the macular capillaries.

The effect of acute hyperglycemia on retinal blood flow was measured in 12 diabetic patients (mean blood glucose, 276 mg%) on continuous subcutaneous insulin infusion and six nondiabetic controls (mean blood glucose, 198 mg%). Flow velocity measurements in macular capillaries were made using the blue field entoptic method. Retinal artery and vein diameters were measured using red-free fundus photographs.

Does microaneurysm count reflect severity of early diabetic retinopathy?

In a group of 55 insulin-dependent diabetic patients with early diabetic retinopathy, microaneurysm counts from fluorescein angiograms were related to the level and severity of retinopathy derived by grading eight standard stereo color photographs as used in the Early Treatment of Retinopathy Study (ETDRS). All patients were studied at 0, 8, and 24 months. Significant correlations were present between both "definite" and "possible" microaneurysm count and retinopathy level of the eye studied and the mean retinopathy level of the two eyes, at all three time intervals, (P less than 0.

Continuous subcutaneous insulin infusion does not provoke significant acute-phase response.

C-reactive protein (CRP), the classical acute-phase reactant, and serum amyloid A protein (SAA), the putative precursor of AA-type amyloid fibrils, were measured in 62 diabetic patients. They were all attending their regular clinic appointments and had been asymptomatic during the 2 wk preceding sampling. CRP and SAA levels were similar in 18 patients on continuous subcutaneous insulin infusion (CSII), 27 patients treated by conventional insulin therapy (CIT), nine treated by diet only, and eight treated by diet and oral hypoglycemic agents, and were almost entirely within the normal range.

Blood pressure and the progression of mild background diabetic retinopathy.

A retrospective 5-year study examined the relationship between blood pressure and the severity and progression of mild background retinopathy in 48 patients with non-insulin-dependent diabetes and 38 with insulin-dependent diabetes who did not receive treatment in either eye for at least 3 years from their initial visit. All patients had annual medical and ophthalmic examinations including fundus photography. Retinopathy was assessed from fundus photographs using the Hammersmith grading system.

Computer-aided digitisation of fundus photographs.

A method is described for the analysis of standard retinal colour photographs with the facility to compare accurately photographs taken serially, thus yielding information on the change in the retinal disease over a period of several years. The reproducibility of placement of a microaneurysm on the same photograph by the same observer is equivalent to +/- 6.6 microns at the retina and inter-observer variation is equivalent to +/- 7.