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Abstract
Routine healthcare data is becoming widely available, usually as a result of administrative systems. Other related data are also often available, such as biochemistry results, mortality data, and sometimes prescribing data. These records are often linked via a common identification system or by probability matching techniques. These data sources offer many opportunities to undertake research, and where prescription data are recorded and linked, the facility to research the outcome of drug use often exists. There are now a number of research agencies around the world that use these large routine data sources to undertake drug safety and outcome studies. The purpose of this commentary is to describe some of the history behind the development of these systems, illustrate some of their uses with respect to postmarketing drug safety and to other healthcare research objectives. The review then describes the data sources necessary to develop a system that would offer an optimal system to undertake a range of studies, including population drug safety surveillance. There are both positive and negative considerations when using routine data. On the positive side, these data come from 'real life' experiences and not from the clinical trial situation. On the other hand, there are important biases to be aware of such as confounding by indication. On the whole, it is argued that large databases originating from routine healthcare procedures have an important role to play in the cost-effective prescription drug use in the postmarketing setting. These systems cannot replace other methods of drug safety evaluation but they do offer an important adjunct to spontaneous reporting systems.
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Lim PO, Donnan PT, MacDonald TM. Does the Dundee Step Test predict outcome in treated hypertension? A sub-study protocol for the ASCOT trial. Anglo-Scandinavian Cardiac Outcome Trial. J Hum Hypertens 2000; 14:75-8. [PMID: 10673735 DOI: 10.1038/sj.jhh.1000931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Treated hypertensive subjects may remain five times more likely to die of cardiac and cerebrovascular diseases than normotensive subjects with equivalent resting blood pressure (BP) levels. Research evidence suggests that exercise BP is a better predictor of end-organ damage and mortality than resting BP, and data from our centre show that a significant proportion of treated hypertensives have uncontrolled BP during a 5-min Dundee Step Test. The prognostic usefulness of exercise BP has yet to be translated into clinical practice because of the lack of a suitable technique. The Dundee Step Test is being evaluated in the ASCOT (Anglo-Scandinavian Cardiac Outcome Trial) study, a 5-year follow-up multicentre, multinational trial comparing the effect of newer (amlodipine and perindopril) and older (bendroflumethiazide and atenolol) antihypertensive agents stratified according to cholesterol levels on cardiac outcome. If the value of the Dundee Step Test is proven, then it may be adopted into routine clinical practice for the assessment of exercise BP. This may result in the improved management of hypertension with a subsequent reduction in morbidity and mortality. The publication of this study protocol is meant to be a statement of on-going research which may stimulate interest among those with an interest in this area of research. Journal of Human Hypertension (2000) 14, 75-78.
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Steinke DT, MacDonald TM, Davey PG. The doctor-patient relationship and prescribing patterns. A view from primary care. PHARMACOECONOMICS 1999; 16:599-603. [PMID: 10724789 DOI: 10.2165/00019053-199916060-00001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The doctor-patient relationship has been described in economic terms as an 'agency relationship' where informed agents make decisions for uninformed clients. However, the decision to prescribe and the decision to accept the prescription by the patient are more complex in nature and involve many variables. Other factors, such as the 'need' for the prescription and the disease state (acute or chronic) also influence prescribing practice. Communication between the physician and patient was found to be important for rational and effective prescribing. The client can make better decisions with the relevant information, thus breaking down the agency relationship that once existed.
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Lim PO, Jung RT, MacDonald TM. Raised aldosterone to renin ratio predicts antihypertensive efficacy of spironolactone: a prospective cohort follow-up study. Br J Clin Pharmacol 1999; 48:756-60. [PMID: 10594479 PMCID: PMC2014356 DOI: 10.1046/j.1365-2125.1999.00070.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS Aldosterone/renin ratio is an index for inappropriate aldosterone activity, and it is increasingly being used to screen for primary aldosteronism within the hypertensive population. It may also be a good index to help predict the response to spironolactone. To assess the blood pressure response to oral spironolactone in hypertensive patients with primary aldosteronism identified with raised aldosterone to renin ratio. METHODS We conducted a prospective cohort study of hypertensive patients with raised aldosterone/renin ratio, who failed to suppress plasma aldosterone with salt loading and fludrocortisone suppression test. These patients were treated with spironolactone and were followed-up for a period of up to 3 years. RESULTS We studied 28 (12 male) subjects with a mean age of 55 (s.d. 10) years who were followed up for a mean period of 12.9 (7) months. At baseline, the patients were taking a mean of 2.1 (1.2) antihypertensive drugs, but despite this 16/28 (57%) had diastolic BP >90 mmHg, 39% with systolic BP >160 mmHg. After commencing spironolactone, three patients complained of breast tenderness but continued treatment and one patient was intolerant of spironolactone and had to stop treatment. Of the remaining 27 patients, the mean number of antihypertensive drugs used dropped to spironolactone plus 0.7 (s.d. 0.9). All but one patient (96%) achieved a diastolic BP</=90 mmHg and 78% achieved a systolic BP</=160 mmHg. In total 48% had BP</=140/90 mmHg and 13/27 (48%) were treated with spironolactone monotherapy. Assessing only patients on drug treatment at baseline (n=24), spironolactone significantly reduced the need for antihypertensive drugs by -0.5 (CI 0.1-1.0), P=0.02, as well as reducing blood pressure [systolic BP -15 mmHg (CI 5-25), P=0.007 and diastolic BP (mmHg) by -8 mmHg (CI 4-13), P=0.001]. CONCLUSIONS Spironolactone was a highly effective antihypertensive agent in hypertensive patients who had a raised aldosterone/renin ratio. As a raised ratio was highly predictive of nonsuppression of plasma aldosterone suggesting primary aldosteronism, it might be worthwhile using spironolactone in this subgroup of hypertensive patients with raised aldosterone/renin ratios, provided that adrenal adenomas are excluded with imaging techniques.
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Struthers AD, Anderson G, MacFadyen RJ, Fraser C, MacDonald TM. Non-adherence with ACE inhibitor treatment is common in heart failure and can be detected by routine serum ACE activity assays. Heart 1999; 82:584-8. [PMID: 10525514 PMCID: PMC1760770 DOI: 10.1136/hrt.82.5.584] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To assess whether serum angiotensin converting enzyme (ACE) activity during routine clinical practice accurately reflects patient adherence to ACE inhibitor treatment for chronic heart failure (CHF). DESIGN Retrospective assessment of ACE inhibitor adherence and serum ACE activity measurements. SETTING Teaching hospital outpatient department PATIENTS AND INTERVENTIONS During 1994-95, serum ACE was measured in 73 CHF patients who were routinely attending the heart failure clinic at Ninewells Hospital. At the same time, the medicines monitoring unit collected data on whether and when prescriptions for ACE inhibitors were redeemed at community pharmacies, which enabled each patient's adherence over a prolonged period to be assessed. MAIN OUTCOME MEASURES Routine collected serum ACE measurements were correlated with measured adherence with ACE inhibitor treatment. RESULTS In total, 18% of CHF patients appeared to exhibit < 70% adherence with their ACE inhibitor treatment with 34% exhibiting less than 85% adherence and 58% exhibiting < 100% adherence. A serum ACE activity of > 12 u/l gave 91% positive predictive accuracy that the patient was < 100% adherent with their ACE inhibitor treatment. At the other extreme, a serum ACE < 6.5 u/l gave 81% positive predictive accuracy that the patient was > 85% adherent with ACE inhibitor treatment. CONCLUSIONS Non-adherence with ACE inhibitor treatment was found to be common in patients with CHF. The simple, inexpensive test of serum ACE activity can be used in CHF patients to identify many, although not all, non-adherent patients so that adherence enhancing strategies can be targeted towards them. Further work is clearly required to explore the precise clinical use of this promising test.
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Dunn NR, Faragher B, Thorogood M, de Caestecker L, MacDonald TM, McCollum C, Thomas S, Mann R. Risk of myocardial infarction in young female smokers. Heart 1999; 82:581-3. [PMID: 10525513 PMCID: PMC1760785 DOI: 10.1136/hrt.82.5.581] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVES To determine the extent of risk of myocardial infarction from cigarette smoking in young women, and to examine the relation of smoking with other putative risk factors. DESIGN Community based case control study. SETTING England, Scotland, and Wales. PATIENTS Women (n = 448) between 16 and 44 years old with a diagnosis of incident myocardial infarction between 1 October 1993 and 16 October 1995. Controls (n = 1728) were age and general practice matched women without a diagnosis of myocardial infarction. OUTCOMES MEASURES Odds ratios for risk of myocardial infarction associated with smoking and other risk factors. RESULTS Odds ratios for myocardial infarction in smokers versus non-smokers showed a strong dose response, from 2.47 (95% confidence interval (CI) 1.12 to 5.45) in smokers of 1-5 cigarettes per day to 74.6 (95% CI 33.0 to 169) in smokers of >/= 40 cigarettes per day. There was no interaction of smoking with use of oral contraceptives, but there were additive risks with other clinical risk factors such as hypertension and diabetes. It is estimated that if all women aged 16-44 years were able to stop smoking, 400 cases of myocardial infarction per annum (of whom 112 would die) would be prevented. CONCLUSIONS In young women the risk of myocardial infarction from smoking was considerable, and heavy smokers with other risk factors were especially at risk.
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Davey PG, McMahon AD, Barbone F, Gillespie WG, Rizvi KA, MacDonald TM. The effect of hip replacement on prescribing of NSAIDs, ulcer healing drugs and hospitalization—a matched cohort study. Pharmacoepidemiol Drug Saf 1999; 8:423-31. [PMID: 15073904 DOI: 10.1002/(sici)1099-1557(199910/11)8:6<423::aid-pds447>3.0.co;2-t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
PURPOSE To assess the impact of total hip replacement on prescribing of non-steroidal anti-inflammatory drugs (NSAIDs), ulcer healing drugs (UHDs) and hospitalization. METHODS Observational matched cohort study. RESULTS There were 282 subjects in the hip replacement cohort and 1691 in the comparator cohort. Dispensing of NSAIDs fell from 89% to 57% after hip replacement but increased from 36% to 39% in comparators. Dispensing of UHDs fell from 33% to 30% after hip replacement but increased from 16% to 23% in the comparators. Hospitalization for upper gastrointestinal events fell from 2.5% to 1.8% after hip replacement but increased from 1.4% to 1.7% in comparators. Hospitalization for other causes increased from 32% to 42% after hip replacement compared with 25% to 28% in comparators. CONCLUSIONS Hip replacement is associated with reduced prescribing of NSAIDs and UHDs. However, any effect on GI admissions will be small compared with increased hospitalization for other causes.
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Davey PG, Clarkson PB, McMahon A, MacDonald TM. Costs associated with symptomatic systolic heart failure. PHARMACOECONOMICS 1999; 16:399-407. [PMID: 10623367 DOI: 10.2165/00019053-199916040-00007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
OBJECTIVE To investigate whether the extent of systolic dysfunction is a useful predictor of the costs of healthcare and social support for patients with heart failure. DESIGN Cross-sectional study with collection of cost data attributed to management of heart failure in the previous year. SETTING Four primary-care practices in Scotland. PATIENTS Patients receiving long term therapy with loop diuretics for suspected heart failure. INTERVENTIONS Two-dimensional and Doppler echocardiography. MAIN OUTCOME MEASURES AND RESULTS Two hypotheses were tested: (i) the proportion of patients incurring costs is higher in patients with abnormal left ventricular (LV) function; and (ii) the median cost per patient that incurs costs is higher in patients with abnormal LV function. Of the 226 patients in the study, 67 (30%) had abnormal systolic function. In comparison with the remaining 159 patients, they had higher healthcare costs [560 Pounds vs 440 Pounds per patient year (1994/1995 values)], were more likely to incur hospital inpatient or outpatient costs [Odds ratio (OR): 2.02; 95% confidence interval (CI): 1.06 to 3.84] and had significantly higher primary-care costs (mean 292 Pounds vs 231 Pounds per patient year; p = 0.02, Mann Whitney test). In contrast, they were no more likely to incur social support costs (OR: 1.22; 95% CI: 0.52 to 2.86) and the mean cost of social support per patient year was lower (234 Pounds vs 373 Pounds). CONCLUSIONS Patients with objectively measured systolic dysfunction incurred significantly higher healthcare costs in the year before diagnosis. This suggests that treatment that improves systolic function will reduce healthcare costs, even in a primary-care population with relatively mild congestive heart failure.
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Evans JM, Newton RW, Ruta DA, MacDonald TM, Stevenson RJ, Morris AD. Frequency of blood glucose monitoring in relation to glycaemic control: observational study with diabetes database. BMJ (CLINICAL RESEARCH ED.) 1999; 319:83-6. [PMID: 10398627 PMCID: PMC28155 DOI: 10.1136/bmj.319.7202.83] [Citation(s) in RCA: 180] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To investigate patterns of self monitoring of blood glucose concentration in diabetic patients who use insulin and to determine whether frequency of self monitoring is related to glycaemic control. SETTING Diabetes database, Tayside, Scotland. SUBJECTS Patients resident in Tayside in 1993-5 who were using insulin and were registered on the database and diagnosed with insulin dependent (type 1) or non-insulin dependent (type 2) diabetes before 1993. MAIN OUTCOME MEASURES Number of glucose monitoring reagent strips dispensed (reagent strip uptake) derived from records of prescriptions. First recorded haemoglobin A1c concentration in the study period, and reagent strips dispensed in the previous 6 months. RESULTS Among 807 patients with type 1 diabetes, 128 (16%) did not redeem any prescriptions for glucose monitoring reagent strips in the 3 year study period. Only 161 (20%) redeemed prescriptions for enough reagent strips to test glucose daily. The corresponding figures for the 790 patients with type 2 diabetes who used insulin were 162 (21%; no strips) and 131 (17%; daily tests). Reagent strip uptake was influenced both by age and by deprivation category. There was a direct relation between uptake and glycaemic control for 258 patients (with recorded haemoglobin A1c concentrations) with type 1 diabetes. In a linear regression model the decrease in haemoglobin A1c concentration for every extra 180 reagent strips dispensed was 0.7%. For the 290 patients with type 2 diabetes who used insulin there was no such relation. CONCLUSIONS Self monitoring of blood glucose concentration is associated with improved glycaemic control in patients with type 1 diabetes. Regular self monitoring in patients with type 1 and type 2 diabetes is uncommon.
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Dunn N, Thorogood M, Faragher B, de Caestecker L, MacDonald TM, McCollum C, Thomas S, Mann R. Oral contraceptives and myocardial infarction: results of the MICA case-control study. BMJ 1999; 318:1579-83. [PMID: 10364115 PMCID: PMC28136 DOI: 10.1136/bmj.318.7198.1579] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To determine the association between myocardial infarction and use of different types of oral contraception in young women. DESIGN Community based case-control study. Data from interviews and general practice records. SETTING England, Scotland, and Wales. PARTICIPANTS Cases (n=448) were recruited from women aged between 16 and 44 who had suffered an incident myocardial infarction between 1 October 1993 and 16 October 1995. Controls (n=1728) were women without a diagnosis of myocardial infarction matched for age and general practice. MAIN OUTCOME MEASURES Odds ratios for myocardial infarction in current users of all combined oral contraceptives stratified by their progestagen content compared with non-users; current users of third generation versus second generation oral contraceptives. RESULTS The adjusted odds ratio for myocardial infarction was 1.40 (95% confidence interval 0.78 to 2. 52) for all combined oral contraceptive users, 1.10 (0.52 to 2.30) for second generation users, and 1.96 (0.87 to 4.39) for third generation users. Subgroup analysis by progestagen content did not show any significant difference from 1, and there was no effect of duration of use. The adjusted odds ratio for third generation users versus second generation users was 1.78 (0.66 to 4.83). 87% of cases were not exposed to an oral contraceptive, and 88% had clinical cardiovascular risk factors or were smokers, or both. Smoking was strongly associated with myocardial infarction: adjusted odds ratio 12.5 (7.29 to 21.5) for smoking 20 or more cigarettes a day. CONCLUSIONS There was no significant association between the use of oral contraceptives and myocardial infarction. The modest and non-significant point estimates for this association have wide confidence intervals. There was no significant difference between second and third generation products.
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Steinke DT, Seaton RA, Phillips G, MacDonald TM, Davey PG. Factors associated with trimethoprim-resistant bacteria isolated from urine samples. J Antimicrob Chemother 1999; 43:841-3. [PMID: 10404326 DOI: 10.1093/jac/43.6.841] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Urine samples with trimethoprim-resistant or trimethoprim-sensitive Gram-negative bacteria and samples with no bacterial growth (NG) were identified. Age-sex matched community controls were generated with each trimethoprim-resistant case. These four groups were evaluated for exposure. Prior trimethoprim use was significantly more common in the trimethoprim-resistant group when compared with the trimethoprim-sensitive or the NG group. Prior hospitalization was significantly less common in the trimethoprim-resistant than the trimethoprim-sensitive group, but not with the NG group. Prior oestrogen exposure was associated with trimethoprim resistance. There were no associations found for diabetes or prior corticosteroid exposure. Community controls were found to be inappropriate controls for the study of trimethoprim-resistant bacteria in urine samples.
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Shiels P, Lim PO, Leary AC, McMahon AD, MacDonald TM. Angiotensin II receptor subtype I antagonism and diastolic cardiac filling in man. Br J Clin Pharmacol 1999; 47:337-8. [PMID: 10215760 PMCID: PMC2014218 DOI: 10.1046/j.1365-2125.1999.00897.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Prach AT, McGilchrist MM, Murray FE, Johnston DA, MacDonald TM. Prescription of acid-suppressing drugs in relation to endoscopic diagnosis: a record-linkage study. Aliment Pharmacol Ther 1999; 13:397-405. [PMID: 10102974 DOI: 10.1046/j.1365-2036.1999.00463.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Although widely used, few data are available on the appropriateness of prescribing of acid-suppressing drugs (ASDs), despite guidelines on the investigation and treatment of dyspeptic patients. METHODS We created a database of 62 000 endoscopy examinations and record-linked these to a prescribing database. Endoscopic diagnoses were classified into peptic, nonpeptic and others. The H2-antagonists, omeprazole and misoprostol, were studied. RESULTS 35 000 patients had one or more endoscopies during 1978-93; two-thirds were over 45 years of age at first endoscopy. A quarter of all patients who had been endoscoped had consistently normal examinations. Peptic oesophageal pathology was the commonest positive finding. A quarter of those prescribed ASDs between 1989 and 1993 had been endoscoped between 1978 and 1993. In those with a peptic diagnosis prescribed any ASD, the pathologies found were: oesophageal (42.9%), duodenal (36.3%) and gastro-pyloric (21.3%). Patients prescribed omeprazole were more likely to have undergone endoscopy than those prescribed other ASDs, and they were also more likely to have peptic oesophageal pathology. Long-term prescribing (>56 days per year) occurred in two-thirds of patients prescribed ASDs and 40% had at least one endoscopy. In those prescribed short-term ASDs, 20% had undergone at least one endoscopy. Peptic and nonpeptic endoscopic pathology was associated with increased ASD prescribing, but a normal endoscopy did not reduce prescribing. CONCLUSION ASD prescribing appeared to be mainly symptom-driven. Positive endoscopic findings increased the prescribing of ASDs, but normal findings did not reduce it.
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Lim PO, Nys M, Naas AA, Struthers AD, Osbakken M, MacDonald TM. Irbesartan reduces QT dispersion in hypertensive individuals. Hypertension 1999; 33:713-8. [PMID: 10024334 DOI: 10.1161/01.hyp.33.2.713] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Angiotensin type 1 receptor antagonists have direct effects on the autonomic nervous system and myocardium. Because of this, we hypothesized that irbesartan would reduce QT dispersion to a greater degree than amlodipine, a highly selective vasodilator. To test this, we gathered electrocardiographic (ECG) data from a multinational, multicenter, randomized, double-blind parallel group study that compared the antihypertensive efficacy of irbesartan and amlodipine in elderly subjects with mild to moderate hypertension. Subjects were treated for 6 months with either drug. Hydrochlorothiazide and atenolol were added after 12 weeks if blood pressure (BP) remained uncontrolled. ECGs were obtained before randomization and at 6 months. A total of 188 subjects (118 with baseline ECGs) were randomized. We analyzed 104 subjects who had complete ECGs at baseline and after 6 months of treatment. Baseline characteristics between treatments were similar, apart from a slight imbalance in diastolic BP (irbesartan [n=53] versus amlodipine [n=51], 99.2 [SD 3. 6] versus 100.8 [3.8] mm Hg; P=0.03). There were no significant differences in BP normalization (diastolic BP <90 mm Hg) between treatments at 6 months (irbesartan versus amlodipine, 80% versus 88%; P=0.378). We found a significant reduction in QT indexes in the irbesartan group (QTc dispersion mean, -11.4 [34.5] milliseconds, P=0.02; QTc max, -12.8 [35.5] milliseconds, P=0.01), and QTc dispersion did not correlate with the change in BP. The reduction in QT indexes with amlodipine (QTc dispersion, -9.7 [35.4] milliseconds, P=0.06; QTc max, -8.6 [33.2] milliseconds, P=0.07) did not quite reach statistical significance, but there was a correlation between the change in QT indexes and changes in systolic BP. In conclusion, irbesartan improved QT dispersion, and this effect may be important in preventing sudden cardiac death in at-risk hypertensive subjects.
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Lim PO, Rodgers P, Cardale K, Watson AD, MacDonald TM. Potentially high prevalence of primary aldosteronism in a primary-care population. Lancet 1999; 353:40. [PMID: 10023956 DOI: 10.1016/s0140-6736(05)74868-6] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Record-linkage is the linkage of patient-specific information that is stored separately. Recent advances in computerization have meant that record-linkage techniques in medical research are increasingly being used and refined. In particular, they have made a significant contribution to pharmacovigilance, which involves linking drug exposure to outcomes data. In this article, the contribution of record-linkage in Scotland to medical research is described. The two organizations that utilize record-linkage techniques are the Medicines Monitoring Unit (MEMO) of the University of Dundee and the Information and Statistics Division (ISD) of the NHS in Scotland. Pharmacovigilance is MEMO's main concern (using data from the Tayside region of Scotland), while ISD link health care datasets for Scotland for general health care research. The experience of the two groups is now being combined to carry out drug safety studies in the entire population of Scotland.
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Butler R, MacDonald TM, Struthers AD, Morris AD. The clinical implications of diabetic heart disease. Eur Heart J 1998; 19:1617-27. [PMID: 9857913 DOI: 10.1053/euhj.1998.1284] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Lim PO, Shiels P, MacDonald TM. The Dundee Step Test: a novel exercise test suitable for the outpatient management of hypertension. J Hypertens 1998; 16:1701. [PMID: 9856372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Barbone F, McMahon AD, Davey PG, Morris AD, Reid IC, McDevitt DG, MacDonald TM. Association of road-traffic accidents with benzodiazepine use. Lancet 1998; 352:1331-6. [PMID: 9802269 DOI: 10.1016/s0140-6736(98)04087-2] [Citation(s) in RCA: 327] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Psychomotor studies suggest that commonly prescribed psychoactive drugs impair driving skills. We have examined the association between the use of psychoactive drugs and road-traffic accidents. METHODS We used dispensed prescribing as a measure of exposure in a within-person case-crossover study of drivers aged 18 years and over, resident in Tayside, UK, who experienced a first road-traffic accident between Aug 1, 1992, and June 30, 1995, and had used a psychoactive drug (tricyclic antidepressant, benzodiazepine, selective serotonin-reuptake inhibitor, or other psychoactive drug [mainly major tranquillisers]) between Aug 1, 1992, and the date of the accident. For each driver, the risks of having a road-traffic accident while exposed and not exposed to a drug were compared. FINDINGS 19386 drivers were involved in a first road-traffic accident during the study period. 1731 were users of any study drug. On the day of the accident, 189 individuals were taking tricyclic antidepressants (within-patient exposure odds ratio for an accident 0.93 [95% CI 0.72-1.21]), 84 selective serotonin-reuptake inhibitors (0.85 [0.55-1.33]), 235 benzodiazepines (1.62 [1.24-2.12]), and 47 other psychoactive drugs (0.88 [0.62-1.25]). The risk associated with benzodiazepine use decreased with increasing driver's age and was greater when the breath test for alcohol was positive. A dose-response relation was evident with benzodiazepines. The increased risk with benzodiazepines was significant for long-half-life drugs, used as anxiolytics, and for short-half-life hypnotics (all zopiclone). INTERPRETATION Users of anxiolytic benzodiazepines and zopiclone were at increased risk of experiencing a road-traffic accident. Users of anxiolytic benzodiazepines and zopiclone should be advised not to drive.
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Leary AC, MacDonald TM. Angiotensin II type 1 receptor blockade: a new development in cardiovascular pharmacology. Int J Clin Pract 1998; 52:475-81. [PMID: 10622089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The renin-angiotensin-aldosterone system (RAS) plays a central role in blood pressure regulation and fluid and electrolyte homoeostasis. Blockade of this system with inhibitors of angiotensin-converting enzyme (ACE) has been shown to benefit several groups of patients, including those with essential hypertension, congestive heart failure, and post myocardial infarction. Inhibition of ACE also slows the progression of diabetic renal disease and diabetic retinopathy. The recent development of agents that are specific antagonists of angiotensin II (AII) has allowed us to block the RAS at receptor level. Inhibition of angiotensin II receptors has been shown to reduce blood pressure in hypertensive patients, without the side-effect profile of ACE inhibitors. It has yet to be shown whether manipulating the RAS in this way will confer the same morbidity and mortality benefits as those seen with ACE inhibition. Ongoing research will reveal whether All antagonists are beneficial in congestive heart failure, ischaemic heart disease and diabetes mellitus. The development of this new class of agent provides an exciting opportunity for clinicians to increase their understanding of the role of the RAS in health and disease.
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Tay HL, Evans JM, McMahon AD, MacDonald TM. Aspirin, nonsteroidal anti-inflammatory drugs, and epistaxis. A regional record linkage case control study. Ann Otol Rhinol Laryngol 1998; 107:671-4. [PMID: 9716869 DOI: 10.1177/000348949810700808] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To assess the relationship between nonsteroidal anti-inflammatory drugs (NSAIDs) and spontaneous epistaxis in adults over 50 years old, a case control study was carried out by using a record linkage database for the population of Tayside, Scotland, which included 319,465 people. The study group consisted of 326 patients who were hospitalized with epistaxis between May 1989 and December 1992, but who had not previously been hospitalized with this diagnosis. Six community controls and 4 hospital controls, matched for age and sex to each case, were used. Previous exposure to prescribed aspirin and other NSAIDs was investigated. There was a significant association between aspirin exposure and epistaxis when either community or hospital controls were used (p < .001). Patients who had aspirin prescriptions had a relative risk of hospital admission for epistaxis of between 2.17 and 2.75, depending on the control group used. No association between non-aspirin NSAIDs and epistaxis was evident with either control group.
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Prasad N, Clarkson PB, MacDonald TM, Ryan M, Struthers AD, Thompson CJ. Atrial natriuretic peptide increases urinary albumin excretion in men with type 1 diabetes mellitus and established microalbuminuria. Diabet Med 1998; 15:678-82. [PMID: 9702472 DOI: 10.1002/(sici)1096-9136(199808)15:8<678::aid-dia639>3.0.co;2-k] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Raised plasma concentrations of atrial natriuretic peptide (ANP) have been reported in patients with Type 1 (insulin dependent) diabetes mellitus (DM) who have poor glycaemic control and are associated with the presence of microalbuminuria. To test the hypothesis that elevations in plasma ANP concentration increase urinary albumin excretion in Type 1 DM, we have studied the effects of intravenous infusions of ANP in eight such subjects with established microalbuminuria. Blood glucose was maintained between 4 and 7 mmol l-1 in all subjects for the duration of studies; after euglycaemia had been established, a standard oral water load (20 ml kg-1 plus replacement of urinary losses) was given. Once steady state diuresis was attained, subjects received intravenous infusion of either placebo (0.9% saline), low dose (2.5 pmol kg-1 min-1) or high dose (5.0 pmol kg-1 kg min-1) ANP solution in a randomized, double-blind protocol. Infusion of ANP caused a dose-dependent increase in urinary albumin excretion rate (placebo, 11.3 (SD 8.9) to 8.7 (SD 6.8) micrograms min-1; low dose ANP, 12.4 (SD 9.9) to 26.5 (SD 27.5) micrograms min-1, p < 0.01; high dose ANP 10.3 (SD 7.3) to 36.6 (SD 28.5) micrograms min-1, p < 0.001, ANOVA). Only high dose ANP caused an increase in urine flow. Blood glucose remained unchanged in all studies. We conclude that intravenous infusions of ANP cause a dose-dependent increase in urinary albumin excretion rate in Type 1 DM subjects with microalbuminuria. These data support the hypothesis that ANP has albuminuric actions which may contribute to microalbuminuria in Type 1 DM.
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Abstract
Epidemiological evidence suggests that 20 to 40% of all patients with heart failure have normal systolic function. Isolated diastolic dysfunction may be the principle pathophysiological mechanism in these patients. The diagnosis of isolated diastolic heart failure is problematic and not merely based on demonstrating normal systolic function. The prognosis in isolated diastolic heart failure is more favourable than in systolic heart failure. At the present time, there is no licensed treatment for isolated diastolic heart failure and treatment is largely empirical.
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