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G V Gill

Publications and source records attributed to G V Gill.

At least 37 records · Page 2Linked to original sources

Enumeration of non-communicable disease in rural South Africa by electronic data linkage and capture-recapture techniques.

Non-communicable diseases (NCDs) are becoming increasingly common and important in developing countries, yet their enumeration is problematic. We have attempted to enumerate NCD patients in a rural district of KwazuluNatal, South Africa, using the techniques of electronic data linkage and capture-recapture (CR). We examined four major NCDs (hypertension, diabetes, asthma and epilepsy). Basic patient details were recorded onto EpiInfo software over a 6-week period, from the main hospital clinic at Hlabisa, as well as the 10 outlying peripheral health clinics. Using electronic data linkage of lists from the main hospital, the peripheral clinics, and repeat prescription cards, a district NCD register was produced of 2455 patients. The mean age was 51 +/- 16 years (1 SD) and 76% were female. Of the total NCD patients, 62% had hypertension (age 57 +/- 12 years, 82% female), 16% epilepsy (age 35 +/- 17 years, 49% female), 13% asthma (age 45 +/- 19 years, 60% female) and 12% diabetes (age 54 +/- 13 years, 61% female). Estimated population crude prevalence rates for known NCD cases on the register were 7.4% for hypertension, epilepsy 0.2%, asthma 0.2% and diabetes 0.2%. We also attempted a CR analysis to assess completeness of data, by comparing overlap between patients attending peripheral clinics, and the central Hlabisa Hospital clinic. Matching by name, age, and diagnosis proved feasible, but there was little overlap, and CR calculations were invalid because of the relative independence of sources. We conclude that NCDs are common in rural Africa, and that a simple NCD district register is a potentially feasible and inexpensive option. Capture-recapture analysis is feasible, but requires suitable lists with acceptable overlap of patients.

Adolescent↗

Institutional dietary provision for diabetic patients.

We compared the diet of residents with diabetes with current British Diabetic Association (BDA) recommendations, and the nutritional adequacy and content of the diet using 3-day food diaries. We studied 52 residents with diabetes and 48 age- and sex-matched controls from 37 nursing, residential and elderly mentally infirm homes in one city. The daily intake of fat, protein, carbohydrate and fibre of the group with diabetes did not comply with current BDA guidelines, and 52% of diabetic residents and 46% of controls had a lower daily energy intake than currently recommended. The diet of diabetic residents did not comply with current recommendations. Undernutrition is common in both groups.

Aged↗

Brittle diabetes in the elderly.

Severely unstable, or brittle, diabetes can be disruptive to patients, carers and diabetes care teams. The peak age-group for brittle diabetes is 15-30, but there are reports of its occurrence in much older patients. To explore the characteristics and cause of brittle instability perceived by diabetologists in elderly patients we circulated a questionnaire to all UK hospital diabetic clinics for adults. 130 (56%) of 231 replied. Reports were obtained on 55 patients fulfilling our criteria for 'elderly brittle diabetes'--namely, age > or =60 years, on insulin treatment, and experiencing life-disrupting glycaemic instability of any kind associated with frequent or long admissions to hospital. Further information was obtained by a research nurse who visited the relevant clinics. The mean age of patients was 74 years (range 60-89) and 71% were female. The brittleness was classed as mixed glycaemic instability in 22 (44%), recurrent ketoacidosis in 16 (29%) and recurrent hypoglycaemia in 15 (27%). In 2 cases there was insufficient information for classification. The diabetes care team judged the brittleness to have multiple origins in two-thirds of the cases: problems with memory or behaviour were rare, and in only 4 cases was deliberate manipulation of therapy considered a possibility. 84% of the patients were living independently. In younger patients the principal manifestation of brittle diabetes is recurrent ketoacidosis. The present survey, though possibly subject to ascertainment bias, indicates that the patterns of instability and their causation may be different in elderly patients. With the growing use of insulin in the elderly, brittle diabetes is likely to be encountered increasingly often in this age-group.

Aged↗

Hyponatremia.

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Humans↗

Comparison of questionnaire, breath carbon monoxide and urine cotinine in assessing the smoking habits of Type 2 diabetic patients.

AIMS: Previous studies have suggested that the self-reporting of smoking amongst diabetic patients is unreliable, and that objective markers such as breath carbon monoxide (CO) or urinary cotinine are needed. As these studies have been mostly in young Type 1 diabetic patients, the reliability of smoking history has been assessed in a large group of older Type 2 diabetic patients. METHODS: Two hundred and ninety-nine Type 2 diabetic patients were investigated for smoking habits by unstructured questionnaire, breath CO, and urinary ratio. RESULTS: Mean age of the group was 63 (range 30-80) years and 41% were female. Direct questioning suggested 77 (26%) to be smokers, and of these 852 had raised (>1 microg/mg) urinary cotinine-creatinine , and 71% raised (>8 p.p.m.) breath CO. Assuming urinary cotinine-creatinine as the 'gold standard', the sensitivity, specificity and positive predictive values for questionnaire were 97%, 95% and 85%, respectively; and for breath CO they were 74%, 98%, and 93%. CONCLUSION: It is concluded that at least in this population of Type 2 diabetic patients, a structured smoking history appeared to identify current smokers with good accuracy.

Adult↗

Variation in licensing authority standards for diabetic taxi drivers in the United Kingdom. Driving and Employment Working Party of the British Diabetic Association.

In the UK, prospective taxi-drivers with diabetes are licensed locally according to variable criteria. In order to determine the criteria used for licensing, questionnaires were sent to all 422 local licensing authorities. Responses were obtained from 372 authorities (88% response rate). Only 201 (54%) currently issue licences to drivers on insulin treatment, and 260 (70%) to those on diet and/or oral hypoglycaemic agents. Most local authorities would prefer taxi-licensing to operate centrally rather than locally. It is apparent that the current UK system for licensing diabetic taxi drivers is variable and not evidence-based. A nationally organized system with clearly defined criteria and the capacity for individual consideration, would be more fair and consistent, and would be unlikely to compromise road safety.

Automobile Driving↗

Brittle Addison's disease: a new variation on a familiar theme.

Unstable and unpredictable disease control in diabetes or asthma, with frequent hospitalisations, is frequently referred to as 'brittle'. We describe two cases of Addison's disease with recurrent hospitalisations in hypo-adrenal crises. Both patients had significant psychosocial disruption, and failure to take hydrocortisone replacement therapy was admitted in one and biochemically proven in the other. We propose that 'brittle' Addison's disease in these cases was due to poor treatment compliance related to psychosocial factors. These features have particular similarities with the syndrome of brittle diabetes.

Addison Disease↗

Can plasma fructosamine substitute for glycated haemoglobin (HbA1c) estimation in the assessment of diabetic control?

The 'gold standard' marker of overall glycaemic control in diabetes mellitus is the level of glycated haemoglobin (HbA1c). It is, however, an expensive and technically difficult assay and is rarely appropriate to tropical laboratories. Plasma fructosamine measurement is cheaper and easier, though it reflects shorter-term glycaemia. We have measured both indices of control in a group of 154 diabetic patients. There was close correlation between the two measurements (r = 0.6506, P < 0.001), but many patients with abnormal HbA1c levels had normal fructosamine levels. This resulted in an assay sensitivity (compared with HbA1c as gold standard) of only 30%, though specificity was 98%. We conclude that fructosamine measurement cannot be regarded as a substitute for HbA1c determination.

Adolescent↗

How many data sources are needed to determine diabetes prevalence by capture-recapture?

BACKGROUND: Capture-recapture (CR) methods are increasingly used to estimate the size of human populations, including those with diabetes. Few studies have examined the demographic details needed to match patients on the lists used in these techniques, or to determine the optimum number of lists. METHODS: Six lists of known diabetic patients attending different medical settings during the study year were obtained. The effects on total enumeration after aggregation of these lists were examined using increasing numbers of demographic data items as patient identifiers. The CR estimates of prevalence were obtained using 15 different combinations of two lists. Estimates were obtained after log-linear modelling for interdependence between different combinations of three and four lists, and after combining the six available lists into three logical lists. RESULTS: For matching patients, adding date of birth to first name and family name as matching criteria increased the total of identified patients from 2500 to 2585 (3% increase), corresponding to a period prevalence of 1.5% (95% CI : 1.41-1.52). Addition of further identifiers, such as partial postcode, only increased the estimate by a further 15 patients (0.5%), and more detailed matching with full postcode introduced uncertainty. The use of two-list CR yielded widely varying estimates of the total diabetic population from 1379 (95% CI : 435-2273) to 9554 (95% CI : 7291-10 983). Log-linear modelling using different combinations of three and four lists produced estimates of 5074 (95% CI : 4417-5947) and 5578 (95% CI : 4918-7081), respectively, after compensating for statistical interdependence between the lists used. The appropriate condensation of six available lists into three lists for modelling yielded estimates of 5492 (95% CI : 4870-6285), corresponding to a CR-adjusted period prevalence of 3.1% (95% CI : 3.03-3.19%). CONCLUSIONS: In a Western population, the only demographic data required for matching patients on lists used for CR methods are first name, family name and date of birth, if unique identifiers such as social security numbers are not available. Two lists alone do not produce reliable data, and at least three lists are needed to allow for modelling for 'dependence' between datasets. The use of more than three lists does not substantially alter the absolute value or confidence of enumeration, and multiple lists (if available) should be condensed into three lists for use in CR calculations.

Databases, Factual↗

Is undetected autonomic dysfunction responsible for sudden death in Type 1 diabetes mellitus? The 'dead in bed' syndrome revisited.

AIMS: Sudden nocturnal death in young persons with Type 1 diabetes mellitus has been recently described, and is known as the 'dead in bed' syndrome. Its aetiology is unknown, and we have therefore explored the details of all papers recording the syndrome, to formulate a hypothesis of causation. METHODS: Literature review of 'dead in bed' reports as well as of nocturnal hypoglycaemia, and autonomic dysfunction in relation to baroreceptor-cardiac reflex sensitivity. RESULTS: Clinical reports of 'dead in bed' cases strongly suggest that nocturnal hypoglycaemia is a likely precipitant, but that the death is sudden and probably arrhythmic. Ventricular dysrhythmias may occur in the context of early autonomic neuropathy, with relative sympathetic overactivity, in young Type 1 diabetic persons. CONCLUSION: We conclude that the 'dead in bed' syndrome probably occurs in Type 1 diabetic persons with early autonomic neuropathy, resulting in relative sympathetic overactivity. In such persons, risks of ventricular dysrhythmias will be compounded by nocturnal hypoglycaemia, which may be associated with an increase in the electrocardiographic Q-T interval, and Q-T dispersion. This could lead to the observed sudden death in undisturbed beds. Further research in this area is urgently needed, in particular into the possible protective use of drugs that modulate the autonomic nervous system.

Autonomic Nervous System Diseases↗

The epidemiology of Type 2 diabetes and its current measurement.

Type 2 diabetes is globally increasing in prevalence and is widely recognized as a major cause of morbidity and mortality, as well as being a burden to the health-care services. Planning for current and future diabetes services requires up-to-date prevalence information. The enumeration of Type 2 diabetes is, however, surprisingly difficult. Large numbers of people are undiagnosed, and those known cases have variable loci of care. Traditional techniques include cross-sectional diagnostic surveys, postal or house-to-house surveys and cohort surveys. All are time-consuming and expensive, and may potentially undercount. The use of multiple patient lists (e.g. hospital clinic data, general practitioner (GP) lists, prescribing information, etc.) can, however, increase accuracy and, if the data are computerized, may be rapid and inexpensive. A new and potentially exciting tool to utilize multiple lists in Type 2 diabetes prevalence assessment is known as 'capture-recapture'. In this, statistical models are used to estimate prevalence from the degree of overlap between lists. Capture-recapture is emerging as a valuable tool in the epidemiological assessment of Type 2 diabetes.

Animals↗

Capture-recapture-adjusted prevalence rates of type 2 diabetes are related to social deprivation.

We examined the prevalence of type 2 diabetes and social deprivation in one urban district in Liverpool from October 1995 to September 1996 inclusive. This area has a stable Caucasian population of 176, 682. Lists were made of all known diabetics attending six different medical points of contact during the year, and were condensed and aggregated to eliminate duplicates. From postcode data, each patient was assigned to residence in one of the 14 electoral wards in the district, for which demographic structure and standardized measures of social deprivation were known (Townsend index). The crude period prevalences of type 1 and type 2 diabetes were estimated for each ward. Crude prevalence data were then corrected by applying capture-recapture (CR) techniques to the different patient datasets to allow for undercount. The crude period prevalence (95%CI) of diabetes was 1.5% (1.4-1.5%), or 2585/176, 682. The mean age of people with diabetes was not significantly different between electoral wards. The crude period prevalence of type 2 diabetes within individual wards ranged from 0.4% (0.3-0.6%) in the least deprived area to 4.1% (3.6-4.6%) in the most deprived area. The corresponding range of CR-adjusted period prevalence rates of type 2 diabetes was from 3.2% (2.8-3.6%) to 6.7% (6.1-7.4%), and there was strong correlation between both crude and CR-adjusted prevalence and social deprivation in each ward (r=0.76, p<0.001 for crude; and r=0. 49, p<0.005 for CR-adjusted prevalence). There was no correlation between the crude or CR-adjusted period prevalence rates of type 1 diabetes and Townsend index (r=0.14, p=NS). This strong correlation between the prevalence of type 2 diabetes and social deprivation has important implications for the planning of health-care delivery.

Adolescent↗

Carcinoid-associated ectopic ACTH syndrome with variable response to octreotide.

The case is presented of a 31-year-old woman who developed florid clinical and biochemical Cushing's syndrome due to metastatic hepatic carcinoid tumour from a probable pancreatic primary. Hypercortisolaemia was controlled with metyrapone and ketoconazole, but high doses of octreotide failed to affect plasma cortisol and urinary 5-hydroxyindole acetic acid (5HIAA) levels, or prevent rapid tumour growth. Hepatic polystyrene embolisation failed, and she was treated by liver transplantation with initial excellent results, and normalisation of cortisol and 5HIAA levels. Ten months later, however, she relapsed with bony and pelvic tumour recurrence, and high and symptomatic levels of cortisol and 5HIAA. At this time, octreotide in similar doses to those used previously appeared to normalise her biochemically, although she died soon after. This variable responsiveness to octreotide could be related to somatostatin receptor changes, or cyclical tumour secretion patterns.

ACTH Syndrome, Ectopic↗