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In order to determine the factors related to the occurrence of hypertension in diabetic patients, blood pressure distributions were determined, using standardised methods, in a sample of 5,842 patients attending ten diabetic clinics in the London area. After allowing for the influence of age and obesity, BPs tended to be higher in patients with non-insulin-dependent diabetes compared with those with insulin-dependent diabetes, and were in general higher in males compared with females. Average BPs were lower in South Indian patients when contrasted with Caucasians and Afro-Caribbeans. The frequency of WHO-defined hypertension was highest in the non-insulin-dependent patients older than 55 years, being 43% for males and 52% for females. A substantial proportion of subjects already taking anti-hypertensive treatment had BPs above 160/95 mmHg. Centile distributions of BP in this population have been used to assess the implications of treatment strategies in diabetic patients.

We have examined the relationship between baseline variables and the incidence of new macrovascular complications amongst the 497 members of the London cohort of the WHO Multinational Study of Vascular Disease in Diabetics over a mean 8.33-year follow-up. In univariate logistic regression analysis the incidence of new ischaemic electrocardiographic abnormality was significantly associated with systolic and diastolic blood pressure, diabetes duration and hypertension in patients with insulin-dependent diabetes, and with smoking in patients with non-insulin-dependent diabetes. New myocardial infarction was associated with systolic blood pressure, plasma cholesterol, proteinuria and smoking in patient with non-insulin-dependent diabetes; there were no significant associations among patients with insulin-dependent diabetes. All new ischaemic heart disease was associated with hypertension in patients with insulin-dependent diabetes, and plasma cholesterol and smoking in patients with non-insulin-dependent diabetes. New cerebrovascular disease was associated with systolic and diastolic blood pressure, ECG abnormality and hypertension. New peripheral vascular disease was associated with smoking. Multivariate analysis showed the following significant associations 1) in patients with insulin-dependent diabetes: ECG abnormality; hypertension, myocardial infarction; smoking, ischaemic heart disease; hypertension, diabetes duration and smoking, 2) in patients with non-insulin-dependent diabetes: ECG abnormality; smoking, myocardial infarction; serum cholesterol, proteinuria and smoking ischaemic heart disease; smoking. For new cerebrovascular disease, proteinuria and ECG abnormality were significant predictors in multivariate analysis. Patients with diabetes share many of the established risk factors for nondiabetic subjects, in addition proteinuria may be of significance in the prediction of macrovascular disease in diabetes.

We report on the incidence of new macrovascular disease among the 497 members of the London Cohort of the WHO Multinational Study of Vascular Disease in Diabetics (aged 35-54 years at recruitment) over a mean 8.33 year follow-up period. Overall at the end of the follow-up period the prevalence of macrovascular disease in the cohort was 45%; 43% of the subjects showed evidence of ischaemic heart disease, 4.5% of cerebrovascular disease and 4.2% of peripheral vascular disease. The incidence rates for new disease in those subjects who were free at baseline expressed per 1000 patient years of follow-up were: ischaemic ECG abnormality 23.6 (patients with insulin-dependent diabetes 19.8, patients with non-insulin-dependent diabetes 28.1), myocardial infarction 17.6 (patients with insulin-dependent diabetes 16.5, patients with non-insulin-dependent diabetes 18.8), all ichaemic heart disease 31.7 (patients with insulin-dependent diabetes 30.3, patients with non-insulin-dependent diabetes 33.4), cerebrovascular disease 5.9 and peripheral vascular disease 5.2. Incidence rates were generally similar among men and women except for myocardial infarction in patients with non-insulin-dependent diabetes where men had a significantly higher incidence rate. Macrovascular disease is a major problem in patients with diabetes and in this age group is mainly manifested as ischaemic heart disease.

Using the Life Events and Difficulties Schedule of Brown and Harris, the relationship between preceding stress and the onset of diabetic complications and premature death was investigated prospectively in a random sample of 130 patients with diabetes, aged 35-59 years. The presence of stress, assessed as severe life-events and severe long-term difficulties, was not significantly associated with premature death or the onset of macrovascular disease over the relatively short period of follow-up (4 years). Those who commenced anti-hypertensive therapy during the follow-up period were significantly more likely to have experienced five or more severe life-events during the previous 5 years (40 vs 6%, p less than 0.01), and also to have experienced one or more severe long-term difficulties during the same time period (60 vs 28%, p less than 0.05). A multiple Cox regression analysis showed that the effects of stress were independent of other factors such as baseline blood pressure, type of diabetes, sex, and ethnic group.

The 497 members of the London Cohort of the WHO Multinational Study of Vascular Disease in Diabetics have been followed for mortality from 1975 to 1987. During this period 92 patients died. The most common cause of death was myocardial infarction: 36 (39.1%) deaths, heart disease was responsible for 51.1% of deaths and all cardiovascular disease for 55.4%. Neoplastic disease accounted for 25% of the deaths and diabetic nephropathy for 5.4%. Age-standardised mortality rates were higher in men than in women in both Type 1 (insulin-dependent) diabetes and Type 2 (non-insulin-dependent) diabetes. Standardised mortality ratios for the first and second five year follow-up periods were higher for men than for women in Type 2 diabetes but were higher for women than men in Type 1. The results suggest that the female survival advantage seen in the general population may persist in Type 2 but not in Type 1 diabetes.

Potential risk factors have been examined for association with mortality over a 10-12 year follow-up of the patients of the London Cohort of the WHO Multinational Study of Vascular Disease in Diabetics (aged 35-54 years at entry to the study). Proteinuria has the strongest association with all-cause mortality in univariate analysis being significant in patients of both sexes with Type 2 (non-insulin-dependent) diabetes mellitus and in women with Type 1 (insulin-dependent) diabetes mellitus; both systolic blood pressure (men) and hypertension (both sexes) (as a categorical variable) are significant in Type 1 diabetes. Hypertension is also significantly associated with all-cause mortality in multivariate analysis in both sexes with Type 1 diabetes as proteinuria is in women with Type 2 diabetes. There is an unexpected negative association between plasma creatinine and all-cause mortality in men with Type 2 diabetes. Systolic blood pressure and hypertension are also significantly linked with cardiovascular mortality in Type 1 diabetes, hypertension having an estimated relative risk of 4.6 [corrected] in multivariate analysis. Serum cholesterol and proteinuria showed the strongest associations with cardiovascular mortality in Type 2 diabetes. Proteinuria is associated with non-cardiovascular mortality in both types of diabetes in univariate but not multivariate analysis. In multivariate analysis hypertension (Type 1 diabetes) and diabetes duration (Type 2 diabetes) are associated with non-cardiovascular mortality. Hypertension and proteinuria have the most consistent associations with mortality in the different analyses with the effect of hypertension appearing stronger in Type 1 diabetes and proteinuria in Type 2 diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)

Data from the clinical records of patients known to have diabetes and admitted to hospital in North West London, Cambridge or Newcastle were compared with data on the same admissions taken from the system responsible for recording information on all acute hospital admissions (Hospital Activity Analysis). In 89 out of 751 admissions (12%), either the sex, date of birth or marital status of the patient was incorrectly recorded. The diagnosis of diabetes was omitted in 32 (10%) of 315 admissions in which diabetes or a complication of diabetes was regarded as the principal cause of admission and in 12 (23%) out of 53 in which the principal cause was closely related to diabetes. These included cases in which the diagnosis had not been stated (by the clinician) on the discharge summary (the source document for Hospital Activity Analysis) as well as instances in which the coding clerk had failed to record the diagnosis. The validity of information collected on hospital admissions is dependent on the presentation of data by the clinician to the coding clerk. There may be a lack of awareness of the importance of the clinical discharge summary as a source document for such systems.

Adenovirus uncouples DNA replication from polyamine biosynthesis and causes chromosome aberrations in rodent cells. Addition of polyamines protected infected cells from this chromosome damage. Spermine was the only individual polyamine which protected. The diamine oxidase inhibitor aminoguanidine also protected. Neither compound detectably reduced synthesis of viral early proteins. The protective effects of spermine and aminoguanidine were not additive. Maximal protection was obtained when the compounds were added 4.5 h before mitosis, but significant protection was observed up to 1.25 h before mitosis. This suggests that the compounds act in G2. In vitro, spermine bound strongly to DNA and protected it from mild endonuclease attack, but aminoguanidine did neither. We propose that viral infection causes a deficiency in spermine during a critical period G2, possibly accompanied by an increase in endonuclease activity. The resulting chromosome damage can be prevented by adding exogenous spermine, or by inhibiting the oxidative degradation of endogenous spermine.

Mutants dl312, dl314, hr1, and hr3 with mutations in region E1A of adenovirus type 5 were defective for the induction of cell cycle abnormalities detectable by flow cytometry, cell DNA replication, thymidine kinase production, and chromosome aberrations and did not synthesize the viral DNA-binding protein (E2A) in rat cells. dl311, a leaky E1A mutant, induced cell cycle effects at high multiplicity in only one of three experiments, and synthesized the DNA-binding protein. hr7 (E1B) gave a wild-type response in all tests. dl313 was also positive in all tests, although it induced fewer polyploid cells than did wild-type virus, probably because of the leftward extension of the dl313 E1B deletion into E1A. sub315 and sub316, with mutations which also span the E1A-E1B border, synthesized DNA-binding protein, but caused no cell cycle alterations detectable by flow cytometry in rat or mouse cells. Although the participation of other viral early regions cannot be completely excluded, our results suggest that alteration of cell cycle progression is a direct effect of E1A unrelated to its control of other viral early regions, and may be the function of E1A in transformation.