Increasing prevalence and incidence of thyroid disease in Tayside, Scotland: the Thyroid Epidemiology Audit and Research Study (TEARS).

OBJECTIVE: We aimed to describe the changing incidence of thyroid disease in a population-based study in Tayside, Scotland (population 390 000) between 1994 and 2001. DESIGN: A retrospective, data-linkage, population-based study measuring the incidence and prevalence of thyroid disease. PATIENTS: All patients with newly diagnosed, treated and stable thyroid disease in Tayside were identified by electronic linkage of six datasets, including all regional biochemistry data, hospital admissions, deaths and a thyroid follow-up register. RESULTS: The overall prevalence of thyroid dysfunction has increased from 2.3% to 3.8% (1994-2001). The prevalence of ever having had hyperthyroidism increased from 0.86% to 1.26% in females and 0.17% to 0.24% in males (P < 0.0001 for both). The standardized incidence of hyperthyroidism increased from 0.68 to 0.87 per 1000 females/year, representing a 6.3% annual increase (P < 0.0001). The prevalence of primary hypothyroidism increased from 3.12% to 5.14% in females and 0.51% to 0.88% in males (P < 0.0001 for both). The standardized incidence of primary hypothyroidism did not change and varied between 3.90 and 4.89 per 1000 females/year over the 8 years. Incidence of hypothyroidism in males increased from 0.65 to 1.01 per 1000 males/year (P = 0.0017). Mean age at diagnosis of primary hypothyroidism declined in females from 1994 to 2001. CONCLUSIONS: The prevalence of primary hypothyroidism and previous hyperthyroidism has increased in Tayside, Scotland. This is partly due to an increasing incidence of disease, increased ascertainment and earlier diagnosis of disease. This will result in an increased workload for endocrinologists and general practitioners.

Mortality and vascular outcomes in patients treated for thyroid dysfunction.

CONTEXT: There are limited studies describing mortality and morbidity in patients treated for hyperthyroidism, and no data exist for people with treated hypothyroidism. OBJECTIVE: The objective of the study was to describe all-cause mortality and vascular mortality and morbidity in patients after treatment for hyperthyroidism and hypothyroidism. DESIGN: This was a population-based cohort study from 1994 to 2001. SETTING: The study was conducted in Tayside, Scotland. PATIENTS: All patients were treated for thyroid dysfunction. INTERVENTION(S): Event rates among patients with thyroid dysfunction were compared with rates in the general population. We measured standardized mortality ratio and standardized incidence ratio (SIR). MAIN OUTCOME MEASURE(S): The primary outcome was all-cause mortality. The secondary outcome was serious vascular event, the composite end point of nonfatal myocardial infarction, nonfatal stroke, or vascular death. RESULTS: There were 15,889 primary hypothyroid and 3,888 hyperthyroid patients. There were 3,116,719 patient-years of follow-up in 524,152 subjects in the general population. No increase was found in all-cause mortality or serious vascular events in patients with treated hypothyroidism or hyperthyroidism. Nonfatal ischemic heart disease [SIR 1.23, 95% confidence interval (CI) 1.10-1.36] and dysrhythmias (SIR 1.32, 95% CI 1.11-1.57) were increased in treated hypothyroidism when adjusted for age, sex, diabetic status, and previous vascular disease. In treated stabilized hyperthyroidism, only the risk of dysrhythmias was increased (SIR 2.71, 95% CI 1.63-4.24). Risk of heart failure or cerebrovascular disease was not increased in either patient group. CONCLUSIONS: We found no increase in all-cause mortality in subjects with treated thyroid disease. However, there was increased risk of cardiovascular morbidity in patients with treated primary hypothyroidism and dysrhythmias in treated hyperthyroidism.

Amiloride activation of hepatic microsomal glucose-6-phosphatase; activation of T1?

The mechanism of activation of hepatic microsomal glucose-6-phosphatase (EC 3.1.3.9) in vitro by amiloride has been investigated in both intact and fully disrupted microsomes. The major effect of amiloride is a 4.5-fold reduction in the Km of glucose-6-phosphatase activity in intact diabetic rat liver microsomes. Amiloride also decreased the Km of glucose-6-phosphatase activity in intact liver microsomes isolated from starved rats 2.5-fold. Kinetic calculations, direct enzyme assays and direct transport assays all demonstrated that the site of amiloride action was T1, the hepatic microsomal glucose 6-phosphate transport protein. This is, to our knowledge, the first report of an activation of any of the proteins of the multimeric hepatic microsomal glucose-6-phosphatase complex.

Effects of insulin and amino acids on leg protein turnover in IDDM patients.

To determine whether the responses of muscle protein metabolism to insulin and amino acids in patients with insulin-dependent diabetes mellitus (IDDM) were different from those in nondiabetic subjects, leg tissue kinetics of [15N]phenylalanine and [1-13C]leucine and its metabolites were measured in eight insulin-withdrawn IDDM patients and eight nondiabetic subjects during basal insulinemia and during infusion of insulin (0.29 nmol.min-1.m-2). The diabetic patients were studied in the absence of amino acids, and both groups were studied during infusion of a mixed-amino acid solution (AA). In the diabetic patients, insulin alone and combined with additional AA reduced leg tissue phenylalanine release by 42 and 41%, respectively (both P less than 0.05), but uptake was unchanged. Leg tissue leucine oxidation was unchanged by insulin alone but was increased (P = 0.012) fourfold during insulin infusion with additional AA. In the nondiabetic subjects, insulin with AA infusion increased leg tissue phenylalanine uptake (45.7 +/- 7.5 to 73.1 +/- 7.3 nmol.min-1.100 g-1, P less than 0.01). Insulin-stimulated glucose uptake in the diabetic patients (1.60 +/- 0.28 mumol.min-1.100 g-1, P = 0.04). These results suggest that, in IDDM patients, 1) infusion of insulin fails to stimulate muscle protein synthesis even when combined with a substantially increased provision of AA, and 2) compared with nondiabetic subjects, muscle protein synthesis as well as glucose uptake exhibit blunted responses to insulin.

ACE inhibitor use is associated with hospitalization for severe hypoglycemia in patients with diabetes. DARTS/MEMO Collaboration. Diabetes Audit and Research in Tayside, Scotland. Medicines Monitoring Unit.

OBJECTIVE: To evaluate the association between the use of ACE inhibitors and hospital admission for severe hypoglycemia and to explore the effects of potential confounding variables on this relationship. RESEARCH DESIGN AND METHODS: The association between the use of ACE inhibitors and the incidence of hypoglycemia is controversial. A recent study reported that 14% of all hospital admissions for hypoglycemia might be attributable to ACE inhibitors. We performed a nested case-control study, using a cohort of 6,649 diabetic patients taking insulin or oral antidiabetic drugs, on the Diabetes Audit and Research in Tayside, Scotland (DARTS) database. From 1 January 1993 to 30 April 1994, we identified 64 patients who had been admitted to Tayside hospitals with hypoglycemia and selected 440 control patients from the same cohort. RESULTS: Hypoglycemia was associated with the use of ACE inhibitors (odds ratio [OR] 3.2, 95% CI 1.2-8.3, P = 0.023), whereas use of beta-blockers and calcium antagonists was not associated with an increased risk of hospitalization for hypoglycemia with ORs of 0.9 (95% CI 0.3-3.3) and 1.7 (95% CI 0.2-2.1), respectively. There were significant differences between case and control patients in type of diabetes treatment, diabetes duration, place of routine diabetes care, and congestive cardiac failure. These differences did not confound the relationship between ACE inhibitors and hypoglycemia (adjusted OR 4.3, 95% CI 1.2-16.0). CONCLUSIONS: The results show that the association between ACE inhibitor therapy and hospital admission for severe hypoglycemia is not explained by these confounding factors. Although ACE inhibitors have distinct advantages over other antihypertensive drugs in diabetes, the risk of hypoglycemia should be considered.

Diabetes and lower-limb amputations in the community. A retrospective cohort study. DARTS/MEMO Collaboration. Diabetes Audit and Research in Tayside Scotland/Medicines Monitoring Unit.

OBJECTIVE: There are few U.K. data on the incidence rates of amputation in diabetic subjects compared with the nondiabetic population. RESEARCH DESIGN AND METHODS: We performed a historical cohort study of first lower-extremity amputations based in Tayside, Scotland (population 364,880) from 1 January 1993 to 31 December 1994. The Diabetes Audit and Research in Tayside Scotland (DARTS) database was used to identify a prevalence cohort of 7,079 diabetic patients on 1 January 1993. We estimated age-specific and standardized incidence rates of lower-limb amputations in the diabetic and nondiabetic cohorts. Results were compared with a previous study that evaluated lower-extremity amputations in diabetic patients in Tayside in 1980-1982. RESULTS: There were 221 subjects who underwent a total of 258 nontraumatic amputations. Of the 221 subjects, 60 (27%) patients were diabetic (93% NIDDM), and 63% were first amputations. The median duration of diabetes was 6 years (range: newly diagnosed to 41 years). Nonhealing ulceration (31%) and gangrene (29%) were the two main indications for amputation in the diabetic subjects. Of the 161 nondiabetic subjects, 140 (80%) underwent first amputations. The adjusted incidences in the diabetic and nondiabetic groups were 248 and 20 per 100,000 person-years, respectively. Tayside patients with diabetes thus had a 12.3-fold risk of an amputation compared with nondiabetic residents (95% CI 8.6-17.5). The estimated proportion of diabetic patients in the population rose from 0.81% in 1980-1982 to 1.94% in 1993-1994, whereas the absolute rate of amputation in diabetic subjects was unchanged from that in 1980-1982. CONCLUSIONS: These population-based U.K. amputation data are similar to amputation rates in the U.S. Amputation rates appear to have decreased significantly since 1980-1982. The impact of diabetes education and prevention programs that target the processes leading to amputation can now be evaluated.

The thyroid epidemiology, audit, and research study: thyroid dysfunction in the general population.

The objective of this study was to define the level of treated thyroid dysfunction in a complete and representative population base in an area of sufficient dietary iodine intake. We used record-linkage technology to retrospectively identify subjects treated for hyperthyroidism or hypothyroidism in the general population of Tayside, Scotland from 1 January 1993 to 30 April 1997. Thyroid status was ascertained by record linkage of patient-level datasets containing details of treatments for hyperthyroidism and hypothyroidism. We identified 620 incident cases of hyperthyroidism, an incidence rate of 0.77/1000 x yr [95% confidence interval (CI), 0.70-0.84] in females and 0.14/1000 x yr (95% CI, 0.12-0.18) in males. There were 3,486 incident cases of diagnosed primary hypothyroidism, an incidence rate of 4.98/1000 x yr (95% CI, 4.81-5.17) in females and 0.88/1000 x yr (95% CI, 0.80-0.96) in males. For both hyperthyroidism and hypothyroidism, the incidence increased with age, and females were affected two to eight times more than males across the age range. The midyear point prevalence of all-cause hypothyroidism rose from 2.2% in 1993 to 3.0% in 1996. The level of thyroid dysfunction in Tayside, Scotland is higher than previously reported, and it increased from 1993 to 1996.

Bombesin: action on gut hormones and calcium in man.

Bombesin, a peptide with widespread biological actions, has been demonstrated in human tissues by immunological methods. To investigate its effect in man, synthetic bombesin was infused at low doses in six male volunteers. Bombesin at 2.4 pmol kg-1 min-1 produced significant rises in plasma insulin, glucagon, pancreatic polypeptide, gastrin, cholecystokinin, motilin, glucose-dependent insulinotropic polypeptide, neurotensin, enteroglucagon, vasoactive intestinal polypeptide, and serum calcium. In contrast, bombesin caused a profound fall in parathyroid hormone levels and reduced plasma glucose concentrations. A late rise in plasma calcitonin was also observed. Bombesin had no significant effect on the pituitary hormones, TSH, GH, PRL, or cortisol. No hormonal changes or alterations in calcium were noted during saline infusions. Bombesin has a marked stimulatory effect on gastrointestinal hormones, which is unique and opposite to the effect of somatostatin, a potent inhibitor of gut hormone release. Bombesin also influences calcium-regulating hormones, either directly or through its action on gut hormones. The bombesin concentrations achieved with the dosages used were low enough to indicate a possible physiological role for the endogenous peptide.

Clinical studies with the beta-adrenoceptor agonist BRL 26830A.

BRL 26830A is a beta-adrenoceptor agonist drug that shows a high degree of selectivity for thermogenesis and has potential as an antiobesity agent. We undertook a double-blind trial in 40 obese subjects who received either BRL 26830A or placebo for 18 wk. All were prescribed a 3.35 MJ (800 kcal) diet. Weight loss was 15.4 +/- 6.6 (SD) kg on BRL 26830A compared with 10.0 +/- 5.9 kg on placebo (P less than 0.02). The relative weight losses were 0.93% and 0.61%/wk, respectively. Urinary nitrogen excretion was similar in both groups and skinfold measurements indicated a 4-kg difference in fat lost, suggesting that weight loss was mainly from adipose tissue. Psychological assessments showed that BRL 26830A had no adverse effect on mood and no effect on hunger or satiety. Tremor was experienced by 12 of 16 treated subjects who completed the study. It was generally rated as mild, occurred 1 h after dosing, and tended to diminish with time on treatment. Subsequent analysis of the tremor suggested that it is an exaggeration of physiological tremor mediated through skeletal muscle beta 2 adrenoceptors.

Asthma and Cushing's syndrome.

A female patient was treated with high-dose inhaled fluticasone propionate for her asthma. Over 2 years, she developed features of Cushing's syndrome with proximal myopathy, osteopenia, hypertension, depressive psychosis, and cushingoid appearance. She had biochemical evidence of marked adrenal suppression with a 9:00 AM serum cortisol of 20 nmol/L that returned to normal (315 mol/L) after her therapy was changed to budenoside, 0.8 mg/d. Her appearance, mental state, and myopathy also improved with no loss of asthma control. This case illustrates the potential for developing clinically relevant adverse effects of inhaled corticosteroids when given at licensed doses.

Systematic review of the long-term effects and economic consequences of treatments for obesity and implications for health improvement.

OBJECTIVES: To undertake a systematic review of the long-term effects of obesity treatments on body weight, risk factors for disease, and disease. METHODS: The study encompassed three systematic reviews that examined different aspects of obesity treatments. (1) A systematic review of obesity treatments in adults where the methods of the Cochrane Collaboration were applied and randomised controlled trials (RCTs) with a follow-up of at least 1 year were evaluated. (2) A systematic epidemiological review, where studies were sought on long-term effects of weight loss on morbidity and/or mortality, and examined through epidemiological modelling. (3) A systematic economic review that sought reports with both costs and outcomes of treatment, including recent reports that assessed the cost-effectiveness of pharmaceutical and surgical interventions. A Markov model was also adopted to examine the cost-effectiveness of a low-fat diet and exercise intervention in adults with obesity and impaired glucose tolerance. RESULTS: The addition of the drugs orlistat or sibutramine was associated with weight loss and generally improved risk factors, apart from diastolic blood pressure for sibutramine. Metformin was associated with decreased mortality after 10 years in obese people with type 2 diabetes. Low-fat diets were associated with continuing weight loss for 3 years and improvements in risk factors, as well as prevention of type 2 diabetes and improved control of hypertension. Insufficient evidence was available to demonstrate the benefits of low calorie or very low calorie diets. The addition of an exercise or behaviour programme to diet was associated with improved weight loss and risk factors for at least 1 year. Studies combining low-fat diets, exercise and behaviour therapy suggested improved hypertension and cardiovascular disease. Family therapy was associated with improved weight loss for 2 years compared to individual therapy. There was insufficient evidence to conclude that individual therapy was more beneficial than group therapy. Weight lost more quickly (within 1 year), from the epidemiology review, may be more beneficial with respect to the risk of mortality. The effects of intentional weight loss need further investigation. Weight loss from surgical and non-surgical interventions for people suffering from obesity was associated with decreased risk of development of diabetes, and a reduction in low-density lipoprotein cholesterol, total cholesterol and blood pressure, in the long term. Targeting high-risk individuals with drugs or surgery was likely to result in a cost per additional life-year or quality-adjusted life-year (QALY) of no more than 13,000 British pounds. There was also suggestive evidence of cost saving from treatment of people with type 2 diabetes with metformin. Targeting surgery on people with severe obesity and impaired glucose tolerance was likely to be more cost-effective at 2329 British pounds per additional life-year. Economic modelling over 6 years for diet and exercise for people with impaired glucose tolerance was associated with a high initial cost per additional QALY, but by the sixth year the cost per QALY was 13,389 British pounds. Results did not include cost savings from diseases other than diabetes, and therefore may be conservative. CONCLUSIONS: The drugs orlistat and sibutramine appear beneficial for the treatment of adults with obesity, and metformin for obese patients with type 2 diabetes. Exercise and/or behaviour therapy appear to improve weight loss when added to diet. Low-fat diets with exercise, or with exercise and behaviour therapy are associated with the prevention of type 2 diabetes and hypertension. Long-term weight loss in epidemiological studies was associated with reduced risk of type 2 diabetes, and may be beneficial for cardiovascular disease. Low-fat diets and exercise interventions in individuals at risk of obesity-related illness are of comparable cost to drug treatments. Long-term pragmatic RCTs of obesity treatments in populations with obesity-related illness or at high risk of developing such illness are needed (to include an evaluation of risk factors, morbidity, quality of life and economic evaluations). Drug trials that include dietary advice, plus exercise and/or behaviour therapy are also needed. Research exploring effective types of exercise, diet or behaviour and also interventions to prevent obesity in adults is required.

Case report: coma due to oxytetracycline.

An unusual case is reported of coma of gradual onset in a 67-year old woman being treated with oxytetracycline. Ten hours after the last dose, the patient regained consciousness but remained confused with hallucinations for another 24 hours. The possibility of side-effects should be borne in mind in any patient who develops coma whilst on oxytetracycline.

Is aldosterone the missing link in refractory hypertension?: aldosterone-to-renin ratio as a marker of inappropriate aldosterone activity.

Use of the random aldosterone-to-renin ratio (ARR) as a reliable marker of inappropriate aldosterone activity has led to primary aldosteronism (PA) being increasingly diagnosed in hypertensive patients. At least 10% of hypertensives have been found to have PA, the majority of whom presumably have bilateral adrenal hyperplasia or idiopathic hyperaldosteronism as an aetiology for PA. Whilst these patients clearly have excess aldosterone activity, they have in common many features that are found in hypertensive patients in general, amongst which include heightened angiotensin II adrenal sensitivity. Whether these individuals belong within the spectrum of 'essential hypertension' is being debated, but is probably irrelevant clinically since they appear to respond favourably to spironolactone treatment. In addition, there is recent evidence suggesting that these patients overexpress a key enzyme involved in aldosterone production, the aldosterone synthase, the activity of which appears to relate to its genotypic variation.

High prevalence of primary aldosteronism in the Tayside hypertension clinic population.

Primary aldosteronism (PA) was thought to be rare but recent evidence from Australia suggests that it may be more common. As this has important implications in terms of hypertension management, we undertook to screen for this treatable condition in our hypertension clinic. We obtained blood samples in sequential patients referred for assessment in our hypertension clinic in Tayside for plasma renin activity (PRA) and aldosterone. The aldosterone to PRA ratio (ARR) was used as an initial screening test to identify potential patients with PA. Those patients with an elevated ratio (> or =750) were admitted for the salt loading and fludrocortisone suppression test. These patients also underwent adrenal CT scanning, and in selected patients, adrenal scintigraphy. Between May 1995 and January 1997 (21 months), we screened a total of 495 patients. ARR was available in 465 (93.9%) patients. Out of that number, 77 (16. 6%) had an elevated ratio of > or =750, five of whom had an adrenal adenoma (one had previous adrenalectomy). Forty-five of these patients were admitted for the salt loading and fludrocortisone suppression test with 41 positive test results suggesting PA. One patient with a negative salt loading test result however had an adenoma proven on histology. A total of 43 cases of PA were identified, giving a minimum prevalence of 9.2% (43/465). Potentially the prevalence may be up to 15% assuming that the ARR has a sensitivity of 93% (42/45) in predicting PA. In conclusion, about one in 10 patients attending a hypertension clinic may have PA. This suggests that the prevalence of PA in Tayside is as high as that in the Australian hypertensive population, and this is likely to be true elsewhere, with obvious important implications for hypertension management.

Elevated soluble cell adhesion molecules E-selectin and intercellular cell adhesion molecule-1 in type-2 diabetic patients with and without asymptomatic peripheral arterial disease.

AIM: Cell adhesion molecules may serve as markers of endothelial cell activation, and they may well have a role in the pathogenesis of atherosclerotic vascular disease in diabetes mellitus. EXPERIMENTAL DESIGN: a cross sectional, comparative study. SETTING: a teaching University Hospital. Patients and controls. A cohort of diabetic patients with absent peripheral arterial pulses but no history of cardiovascular or cerebrovascular disease i.e. asymptomatic (n=29), median age 68 (36-80) years, (range), diabetes duration 10 (1-43) years and HbA1c 7.7% (4.8-9.6). They were compared to 12 age and sex matched normal non-diabetic controls. INTERVENTION: none. MEASURES: soluble cell adhesion molecules intercellular cell adhesion molecule-1 (ICAM-1) and E-selectin levels measured by ELISA methods. RESULTS: The 29 patients with diabetes, as a whole, were found to have significantly higher median plasma sICAM-1 and sE-selectin of 283 ng/ml (154-1000) (range), and 65.8 ng/ml (20.6-145) vs 237 (147-312.4) and 37.7 (19.8-46.6) respectively, Mann Whitney U test p<0.02, and p<0.002. In the diabetic group, E-selectin correlated with ICAM-1, age and HbA1c: r=0.524 p<0.01, r=0.385 p<0.05 and r=0.393 p<0.05 respectively (Spearman correlation coefficient). CONCLUSION: These results confirm that elevated levels of adhesion molecules, E-selectin and ICAM-1 occur in Type-2 diabetes early in the course of asymptomatic peripheral arterial occlusive disease, and this is related to glycemic control. This suggests that adhesion molecules may have a role in the pathogenesis of atherosclerotic vascular disease in diabetes.

Use of mobile screening unit for diabetic retinopathy in rural and urban areas.

OBJECTIVES: To compare the effectiveness of a mobile screening unit with a non-mydriatic polaroid camera in detecting diabetic retinopathy in rural and urban areas. To estimate the cost of the service. DESIGN: Prospective data collection over two years of screening for diabetic retinopathy throughout Tayside. SETTING: Tayside region, population 390,000, area 7770 km2. SUBJECTS: 961 patients in rural areas and 1225 in urban areas who presented for screening. MAIN OUTCOME MEASURES: Presence of diabetic retinopathy, need for laser photocoagulation, age, duration of diabetes, and diabetic treatment. RESULTS: Compared with diabetic patients in urban areas, those in rural areas were less likely to attend a hospital based diabetic clinic (46% (442) v 86% (1054), p < 0.001); less likely to be receiving insulin (260 (27%) v 416 (34%), p < 0.001 and also after correction for differences in age distribution); more likely to have advanced (maculopathy or proliferative retinopathy) diabetic retinopathy (13% (122) v 7% (89), p < 0.001); and more likely to require urgent laser photocoagulation for previously unrecognised retinopathy (1.4% (13) v 0.5% (6), p < 0.02). The screening programme cost 10 pounds per patient screened and 1000 pounds per patient requiring laser treatment. CONCLUSION: The mobile diabetic eye screening programme detected a greater prevalence of advanced retinopathy in diabetic patients living in rural areas. Patients in rural areas were also more likely to need urgent laser photocoagulation. Present screening procedures seem to be less effective in rural areas and rural patients may benefit more from mobile screening units than urban patients.

The diabetes audit and research in Tayside Scotland (DARTS) study: electronic record linkage to create a diabetes register. DARTS/MEMO Collaboration.

OBJECTIVES: To identify all patients with diabetes in a community using electronic record linkage of multiple data sources and to compare this method of case ascertainment with registers of diabetic patients derived from primary care. DESIGN: Electronic capture-recapture linkage of records included data on all patients attending hospital diabetes clinics, all encashed prescriptions for diabetes related drugs and monitoring equipment, all patients discharged from hospital, patients attending a mobile unit for eye screening, and results for glycated haemoglobin and plasma glucose concentrations from the regional biochemistry database. Diabetes registers from primary care were from a random sample of eight Tayside general practices. A detailed manual study of relevant records for the 35,144 patients registered with these eight general practices allowed for validation of the case ascertainment. SETTING: Tayside region of Scotland, population 391,274 on 1 January 1996. MAIN OUTCOME MEASURES: Prevalence of diabetes; population of patients identified by different data sources; sensitivity and positive predictive value of ascertainment methods. RESULTS: Electronic record linkage identified 7596 diabetic patients, giving a prevalence of known diabetes of 1.94% (0.21% insulin dependent diabetes, 1.73% non-insulin dependent): 63% of patients had attended hospital diabetes clinics, 68% had encashed diabetes related prescriptions, 72% had attended the mobile eye screening unit, and 48% had biochemical results diagnostic of diabetes. A further 701 patients had isolated hyperglycaemia (plasma glucose > 11.1 mmol/l) but were not considered diabetic by general practitioners. Validation against the eight general practices (636 diabetic patients) showed electronic linkage to have a sensitivity of 0.96 and a positive predictive value of 0.95 for ascertainment of known diabetes. General practice lists had a sensitivity of 0.91 and a positive predictive value of 0.98. CONCLUSIONS: Electronic record linkage was more sensitive than general practice registers in identifying diabetic subjects and identified an additional 0.18% of the population with a history of hyperglycaemia who might warrant screening for undiagnosed diabetes.

Long-term weight changes in treated hyperthyroid and hypothyroid patients.

To compare the effect of three treatments for thyrotoxicosis on subsequent body weight, a retrospective survey of 65 patients was performed. The effect of thyroxine replacement on body weight in 25 patients with primary hypothyroidism was also examined. In one year after starting therapy 21 patients treated with carbimazole gained a mean of 5.4kg (95% confidence interval 3.6 to 7.2kg); 20 patients after thyroidectomy gained a mean of 6.3kg (95% c.i. 3.4 to 9.2kg); and 24 patients given radioiodine gained a mean of 7.4kg (95% c.i. 5.2 to 9.6kg), p less than 0.001 in all three groups. The weight gain in the three groups was not significantly different. 54-67% of the weight gain occurred in the first three months. The patients treated for hypothyroidism had lost an insignificant amount of weight 12 months after starting therapy--mean change was -0.6kg (95% c.i. -2.2 to +1.1kg) p greater than 0.1. This data suggests that all patients treated for thyrotoxicosis will gain body weight irrespective of the treatment used, but patients treated for primary hypothyroidism will not lose an appreciable amount of weight. Therefore dietary advice should be given, where appropriate, at the onset of any treatment of thyroid dysfunction.

Astrocytoma presenting with vasculitis.

A cerebral astrocytoma which had remained quiescent possibly for 12 years, presented with blackout, vasculitis and a lupus-like (L-E like) syndrome. The association between tumours and "L-E like" syndromes is reviewed briefly.

Post exertional broad complex tachycardia in a normotensive patient: a rare presentation of phaeochromocytoma.

Phaeochromocytomas are rare cause of secondary hypertension with significant morbidity and mortality, if left untreated. Paroxysms with hypertension are considered as "textbook" presentations but atypical forms represent considerable diagnostic challenge. We report an unusual association between phaeochromocyotoma and post-exertional malignant arrhythmia in a normotensive subject.