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R D Forrest

Publications and source records attributed to R D Forrest.

At least 19 recordsLinked to original sources
PubMed1999

[Report from the medical tent at three rock festivals. Lots of music, great fun and very little drunkeness].

Rock festivals are popular summer attractions in Scandinavia, and each of the largest festivals has its own voluntary medical crew of doctors, nurses and nursing auxiliaries. The medical crew is an important part of the festival safety facilities, providing free acute health care to festival visitors, and thus relieving pressure on local primary health centres and hospitals. In 1998, 797 of the 25,000 visitors to the three-day Hultsfred Festival were treated at the medical tent, 465 of them by a doctor; and 305 of the 17,000 people attending the two-day Fanclub88 event were treated at the medical tent, 132 by a doctor. No figures are available for the 1998 Roskilde Festival in Denmark, but at the 1997 festival, 3,369 of the 95,000 visitors were treated at the medical tent.

Denmark↗
PubMed1995

A study of uranium lung clearance at a uranium processing plant.

A study has been made of the retention of uranium in the lungs of persons exposed chronically to low levels of uranium aerosols at the Y-12 Plant. A new characterization of the workplace aerosols shows an activity median aerodynamic diameter of 8 microns to be representative of the uranium oxides handled at the Y-12 Plant. The usual ICRP respiratory-system model is employed in conjunction with bioassay data from worker exposures to deduce a new set of parameters to describe lung clearance of these aerosols. This new assessment leads to good agreement between in vivo estimates of uranium lung burdens.

Aerosols↗
PubMed1992

A comparison of the relationships of the glucose tolerance test and the glycated haemoglobin assay with diabetic vascular disease in the community. The Islington Diabetes Survey.

We have compared the relationships of fasting and 2 h blood-glucose during a 75 g oral glucose tolerance test, and those of an affinity chromatography assay of glycated haemoglobin, with the presence of vascular complications of diabetes mellitus in 223 subjects without known diabetes aged over 40 years selected from a community screening study population. The subjects included 15 (6.9%) with newly diagnosed diabetes and 52 (24.1%) with impaired glucose tolerance. Employing receiver operating characteristic analysis, the tests were similar in their relationship with three cases of retinopathy, 19 of microalbuminuria and six of peripheral neuropathy. The prevalence of coronary heart disease, defined as angina, myocardial infarction, or electrocardiographic changes of ischaemia, increased linearly across all four quartiles of both 2 h blood glucose and glycated haemoglobin concentration, but using logistic regression analysis, 2 h blood glucose was a better predictor of coronary heart disease than glycated haemoglobin. Receiver operating characteristic analysis also showed that 2 h blood glucose generally performed better than any of four assays of glycated haemoglobin in classifying those subjects with coronary heart disease.

Aged↗
PubMed1991

Misclassification of diabetic subjects may account for the increased vascular risk of impaired glucose tolerance: the Islington Diabetes Survey.

We have studied the associations of macrovascular disease and hypertension with impaired glucose tolerance in a recall sample of 223 subjects selected from a population aged greater than or equal to 40 years who had been screened for diabetes using two separate glucose tolerance tests. Blood pressure was higher in subjects with diabetes, but not in those with impaired glucose tolerance, than in normals. Coronary heart disease, based on ECG criteria and history, was more frequent both in subjects with impaired glucose tolerance (odds ratio 1.94, 95% CI 1.02-3.69) and those with diabetes (odds ratio 3.88, 95% CI 1.33-11.97) than in normals, but the excess in the impaired glucose tolerance group was reduced, and was no longer significant, when adjusted for other variables (odds ratio 1.29, 95% CI 0.62-2.66). Peripheral vascular disease was more frequent in subjects with diabetes, but not in those with impaired glucose tolerance. When the subjects with impaired glucose tolerance on a single test were reclassified according to the results of a separate glucose tolerance test, the prevalence of coronary heart disease increased significantly with increasing degrees of glucose intolerance. Subjects with impaired glucose tolerance on both tests had an adjusted odds ratio of coronary heart disease of 0.90 (95% CI 0.42-1.94) compared with normal subjects. The excess of macrovascular disease in subjects with impaired glucose tolerance may result, at least in part, from the admixture of 'false negative diabetics' in that class.

Adult↗
PubMed1990

Unexplained variability of glycated haemoglobin in non-diabetic subjects not related to glycaemia.

We have studied levels of glycated haemoglobin in a sample of 223 people aged over 40 years without known diabetes mellitus screened in a community study. Each had a glucose tolerance test and glycated haemoglobin measured by four methods - agar gel electrophoresis with and without removal of Schiff base, affinity chromatography and isoelectric focusing. The correlation coefficients between 2 h blood glucose and levels of glycated haemoglobin were between 0.43 and 0.64. This poor correlation was not explained on the basis of assay or biological variability of either 2 h blood glucose or glycated haemoglobin. Multiple regression analysis showed that other assays of glycated haemoglobin contributed to the variance of any single glycated haemoglobin value by 0.1%-52.9% (median 12.8%) compared to the variance of 18.6%-41.4% (median 30.8%) explained by 2 h blood glucose alone, suggesting that in a non-diabetic population, the degree of glucose intolerance may explain only one third of the variance of glycated haemoglobin levels, but other factors operate to produce consistent changes in levels of glycated haemoglobin. Investigation of 42 subjects with consistently high (20 subjects) or low (22 subjects) levels of glycated haemoglobin relative to their 2 h blood glucose level showed no difference in age, gender, body mass index, haemoglobin levels or smoking, although 50% of low glycators had impaired glucose tolerance. Neither ambient blood-glucose levels, as estimated on two five-point blood-glucose profiles, nor dietary intake of carbohydrate, starch, sugars, fibre or alcohol, explained the difference between high and low glycators. The determinants of the consistent interindividual differences in levels of glycated haemoglobin in non-diabetic subjects remain to be determined.

Adult↗
PubMed1990

Diabetes mellitus in north Sweden: prevalence assessed from prescriptions for anti-diabetic agents.

A prescription inventory was performed over a period of 3 months in all pharmacies in Sweden's northernmost province. Norrbotten, in order to assess the prevalence of diabetes treated with insulin and oral anti-diabetic agents. A total of 4869 prescriptions were collected from 3482 individuals, of whom 1746 (50.1%) were men. The prevalence of drug-treated diabetes was thus 13.27/1000 inhabitants (95% confidence interval (CI) 12.8-13.7) in the province. Nearly half (47.9%) of all drug-treated diabetics were treated with insulin and the majority (74%) were over 55 years of age, with only 449 (13%) being less than 40 years old. The prevalence of diabetes was highest in individuals aged 75-84 years; in this age group it was 55.47/1000 (95% CI 50.9-58.7). There was considerable regional variation in the prevalence of diabetes in Norrbotten, with a mean prevalence of 23.84/1000 (95% CI 22.1-25.6) in the municipalities in the Torneå Valley, compared to 13.08/1000 (95% CI 1.19-1.28) for the remainder of Norrbotten. While there was no difference in the prevalence of drug-treated diabetes between men and women in the province as a whole, a slightly higher prevalence was found in women (27.41 vs. 24.73/1000) in the Torneå Valley. The prevalence of diabetes mellitus in individuals over 40 years of age was 36.62/1000 (95% CI 3.73-4.36) in The Torneå Valley, 24.38/1000 (95% CI 22.8-24.7) in the remainder of Norrbotten, and 27.88/1000 (95% CI 2.50-2.68) in the province as a whole. The estimated prevalence of diabetes mellitus in Norrbotten, including patients treated by diet alone, was of the order of 20.21/1000, with a prevalence of 40.00/1000 in subjects over the age of 40 years. Thus the prevalence of diabetes appears to be higher in the Torneå Valley than in the rest of Norrbotten, while it is apparently lower than has been reported in North Finland.

Adolescent↗
PubMed1988

Microalbuminuria as predictor of vascular disease in non-diabetic subjects. Islington Diabetes Survey.

The relation between urinary albumin excretion rate (AER) and vascular disease was studied in 187 subjects aged over 40 selected from 1084 cases attending a diabetic screening project. AER exceeded 20 micrograms/min in 3 of 13 newly diagnosed diabetic subjects (23%) and 16 of 171 non-diabetic subjects (9.4%). There was a weak relation between AER and both systolic and diastolic blood pressures. Coronary heart disease was found in 54 of 164 (32.9%) subjects with AER of 20 micrograms/min or less and in 14 of 19 (74%) with AER above this. Peripheral vascular disease was present in 16 of 165 (9.7%) subjects with AER of 20 micrograms/min or less and 8 of 18 (44%) with a high AER. Logistic regression, including diabetes, impaired glucose tolerance, systolic and diastolic blood pressures, smoking, age, sex, ethnic origin, and body mass index, demonstrated the independence of this relation between AER above 20 micrograms/min and coronary heart disease (odds ratio [OR] 6.38, 95% confidence interval 1.91-21.4) and peripheral vascular disease (OR 7.72, 2.14-27.8). After a mean of 3.6 (SD 0.19) years, 167 subjects (89.3%) were traced. There had been 9 deaths, 3 (2.0%) among 149 subjects with normal AER and 6 (33%) among 18 microalbuminuric subjects (OR 24.33, 5.40-109.7).

Adult↗
PubMed1988

The relationship of hospital admission and fatality from myocardial infarction to glycohaemoglobin levels.

We have performed a study to assess the relative contributions of increased hospital admission rates with acute myocardial infarction and increased hospital case fatality to the excess mortality of subjects with elevated levels of glycohaemoglobin from myocardial infarction. Glycohaemoglobin levels were estimated by isoelectric focussing in 397 subjects without known diabetes mellitus admitted with myocardial infarction and compared with a control population reconstructed from a community sample of 1084 subjects without known diabetes mellitus screened in general practice. In the case-control comparison, glycohaemoglobin levels above the 90th centile were associated with relative risks of 3.1 (95% confidence interval 1.4-6.8) for admission with myocardial infarction and 5.3 (95% confidence interval 2.1-13.4) for death in hospital. Elevated glycohaemoglobin on admission was a predictor of both death and cardiac pump failure among those admitted with myocardial infarction, as was the presence of known diabetes. In those over 40 years of age, the top 1% of the glycohaemoglobin distribution contribute 4.3% of admissions and 9.6% of hospital deaths with myocardial infarction.

Age Factors↗
PubMed1988

The abbreviated glucose tolerance test in screening for diabetes: the Islington Diabetes Survey.

The World Health Organization has recommended a single 2-h post-glucose load blood glucose level as a screening test for diabetes mellitus in epidemiological surveys. We have assessed its characteristics, when compared with a full supervised glucose tolerance test (OGTT), in estimating prevalence, and in diagnosing diabetes in the individual patient. A stratified sample of 223 of 1040 subjects who had participated in a diabetic survey that utilized a single capillary 2-h blood glucose estimation as a screening test were recalled for formal glucose tolerance testing. The numbers of subjects with diabetes at screening and at recall were similar (14/212, 6.6%; 13/216, 6.0%) but only 9 subjects were so classified on both occasions. Thirty-five subjects (16.5%) were suspected of having impaired glucose tolerance (IGT) at screening, and 52 (24.1%) at recall. There was substantial reclassification from screening IGT, with 3/35 worsening to diabetes, and 10/35 returning to normal. Capillary 2-h glucose levels gave an accurate assessment of the prevalence of diabetes but underestimated that of IGT. On the full OGTT, little difference in classification was found when the values of fasting and 1-h blood glucose were used in addition to those of the 2-h blood glucose used alone. The 2-h glucose had a within-subject coefficient of variation of 32.4% which produced substantial reclassification of subjects with levels close to the diagnostic levels for diabetes, and this implies that such individuals should not be classified as having diabetes on the basis of a single glucose tolerance test.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗
PubMed1988

Sodium and blood pressure: positive associations in a north London population with consideration of the methodological problems of within-population surveys.

Blood pressure (BP) and 24-hr urinary sodium (Na) and potassium (K) excretion were measured in 58 men and women aged 40 and above who were selected randomly from the age-sex register of a general practice in North London. All 58 urine collections were reported as complete, but only 28/56 (50%) were classified as 'complete' by the excretion of a biological marker, p-aminobenzoic acid (PABA). Reliability of Na excretion estimated from repeated urine collections was 0.86, indicating that variability of Na excretion within individuals in this middle-aged and elderly population was low. Systolic blood pressure (SBP) was significantly related to 24-hr Na excretion and to 24-hr Na/creatinine ratio. After adjustment for age, sex and body mass index, a SBP-Na regression coefficient of 0.091 mmHg/mmol Na (P = 0.02) was observed. On simple regression analysis, a significant association was also found between diastolic blood pressure and Na (P = 0.04). In the sub-group classified as 'complete' collectors by PABA excretion, BP-Na regression coefficients were larger than in analyses of the sample as a whole. BP was not significantly related to K or Na/K.

4-Aminobenzoic Acid↗
PubMed1988

Four assay methods for glycated hemoglobin compared as screening tests for diabetes mellitus: the Islington Diabetes Survey.

We assessed the utility of four methods of glycated hemoglobin assay (agar gel electrophoresis with Schiff base, agar gel electrophoresis with prior removal of Schiff base, boronate affinity chromatography, and isoelectric focusing) as screening tests for diabetes mellitus, studying 223 subjects undergoing an oral glucose-tolerance test after fasting and 2 h after ingestion of 75 g of glucose. Assessment of glucose tolerance status according to the 1980 World Health Organization diagnostic criteria indicated that 13 subjects (5.8%) had diabetes, 48 (21.5%) had impaired glucose tolerance, and nine (4.0%) could not be classified (six of these because of missing values). Use of receiver-operating characteristic curves to compare the assays as screening tests showed the affinity chromatography assay to be superior. Assays for glycated hemoglobin after fasting had better precision than post-glucose-load assays as screening tests, and test characteristics of glycated hemoglobin assays on fasting subjects were similar to those of the blood-glucose estimation after fasting. We conclude that measurement of glycated hemoglobin may be a useful screening test for diabetes, and that such measurement of stable glycated hemoglobin is as accurate as measurement of fasting blood-glucose in screening for diabetes. For this use, we found methods that measure stable glycated hemoglobin superior to that measuring both stable and labile Schiff-base fractions.

Blood Glucose↗
PubMed1987

The epidemiology of the haemoglobin level--a study of 1057 subjects in general practice.

A prospective survey of the level of haemoglobin (Hb) has been carried out in 1057 subjects (607, 57.4% women) over the age of 40 randomly selected from the age-sex register of a North London group practice. Mean Hb levels were 15.04 +/- s.d. 1.41 g/dl in men and 13.54 +/- s.d. 1.32 g/dl in women (P less than 0.001). In men, Hb levels did not differ between the ethnic groups represented, but women of Mediterranean origin had significantly lower Hb levels than other women (P less than 0.001). There was no social class difference in Hb levels. Women under age 50 had significantly (P less than 0.001) lower Hb levels than older women. Smokers had significantly higher Hb levels than non-smokers (P less than 0.002) and there was a weak correlation with numbers of cigarettes smoked (men rs = 0.07, P = 0.07; women rs 0.14, P less than 0.001). Haemoglobin levels correlated with diastolic blood pressure in both men (r = 0.07, P less than 0.05) and women (r = 0.23, P less than 0.001). Thirty eight subjects (3.6%), 25 women and 13 men, were found to be anaemic (Hb less than 11.5 g/dl in women or less than 12.5 g/dl in men). Anaemia could be confirmed in only six of 19 subjects in whom repeat levels were measured. Screening for anaemia did not uncover any serious disease.

Adult↗
PubMed1987

Short-term effect of a 75 g oral glucose load on glycohaemoglobin levels.

Two hundred and twenty-three subjects out of a total of 347 with various degrees of glucose tolerance were recalled after a screening survey for diabetes. They were a randomly selected sample of people over the age of 40 and they underwent a formal 75 g glucose tolerance test in order to assess the effect of a glucose load on glycohaemoglobin levels measured by four different assay methods. Oral glucose loading was found to affect glycohaemoglobin levels only when these were measured by an agar-gel electrophoretic method that did not remove the labile aldimine-linked Schiff base fraction. The increase in glycohaemoglobin during the glucose tolerance test as estimated by this method was proportional to the 2 h blood glucose level. Glycohaemoglobin levels measured by agar-gel electrophoresis with elimination of the Schiff base, by affinity chromatography and by iso-electric focussing, were not affected by a 75 g oral glucose load. We conclude that blood samples for glycohaemoglobin assay may be collected at any time of the day, without regard to the subject's previous food intake, provided an assay method is used that removed the aldimine-linked labile fraction.

Adult↗