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Morris AD, Boyle DI, McMahon AD, Greene SA, MacDonald TM, Newton RW. Adherence to insulin treatment, glycaemic control, and ketoacidosis in insulin-dependent diabetes mellitus. The DARTS/MEMO Collaboration. Diabetes Audit and Research in Tayside Scotland. Medicines Monitoring Unit. Lancet 1997; 350:1505-10. [PMID: 9388398 DOI: 10.1016/s0140-6736(97)06234-x] [Citation(s) in RCA: 341] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Intensive insulin treatment effectively delays the onset and slows the progression of microvascular complications in insulin-dependent diabetes mellitus (IDDM). Variable adherence to insulin treatment is thought to contribute to poor glycaemic control, diabetic ketoacidosis, and brittle diabetes in adolescents and young adults with IDDM. We assessed the association between the prescribed insulin dose and the amount dispensed from all community pharmacies with the Diabetes Audit and Research in Tayside Scotland (DARTS) database. METHODS We studied 89 patients, mean age 16 (SD 7) years, diabetes duration 8 (4) years, and glycosylated haemoglobin (HbA1c) 8.4 (1.9)%, who attended a teaching hospital paediatric or young-adult diabetes clinic in 1993 and 1994. The medically recommended insulin dose and cumulative volume of insulin prescriptions supplied were used to calculate the days of maximum possible insulin coverage per annum, expressed as the adherence index. Associations between glycaemic control (HbA1c), episodes of diabetic ketoacidosis, and all hospital admissions for acute complications and the adherence index were modelled. FINDINGS Insulin was prescribed at 48 (19) IU/day and mean insulin collected from pharmacies was 58 (25) IU/day, 25 (28%) of the 89 patients obtained less insulin than their prescribed dose (mean deficit 115 (68; range 9-246] insulin days/annum). There was a significant inverse association between HbA1c and the adherence index (R2 = 0.39; p < 0.001). In the top quartile (HbA1c > 10%), 14 (64%) of individuals had an adherence index suggestive of a missed dose of insulin (mean deficit 55 insulin days/annum). There were 36 admissions for complications related to diabetes. The adherence index was inversely related to hospital admissions for diabetic ketoacidosis (p < 0.001) and all hospital admissions related to acute diabetes complications (p = 0.008). The deterioration in glycaemic control observed in patients aged 10-20 years was associated with a significant reduction (p = 0.01) in the adherence index. INTERPRETATION We found direct evidence of poor compliance with insulin therapy in young patients with IDDM. We suggest that poor adherence to insulin treatment is the major factor that contributes to long-term poor glycaemic control and diabetic ketoacidosis in this age group.
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Abstract
Treatment with ibuprofen might limit the cardioprotective effects of aspirin. We aimed to assess whether patients with known cardiovascular disease who take low-dose aspirin and ibuprofen have increased risk of cardiovascular mortality. We studied 7107 patients who were discharged after first admission for cardiovascular disease between April, 1989, and April, 1997, and who were prescribed low-dose aspirin (<325 mg/day) and survived for at least 1 month. Compared with those who used aspirin alone, patients taking aspirin plus ibuprofen had an increased risk of all-cause mortality (adjusted hazard ratio 1.93, 95% CI 1.30-2.87, p=0.0011) and cardiovascular mortality (1.73, 1.05-2.84, p=0.0305). Our finding lends support to the hypothesis that ibuprofen may interact with the cardioprotective effects of aspirin, at least in patients with established cardiovascular disease.
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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: 12.1] [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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Donnan PT, MacDonald TM, Morris AD. Adherence to prescribed oral hypoglycaemic medication in a population of patients with Type 2 diabetes: a retrospective cohort study. Diabet Med 2002; 19:279-84. [PMID: 11942998 DOI: 10.1046/j.1464-5491.2002.00689.x] [Citation(s) in RCA: 302] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To evaluate the patterns and predictors of adherence in all patients with Type 2 diabetes in the community receiving treatment with a single oral hypoglycaemic drug. In particular, to test the hypothesis that one tablet per day is associated with better adherence than more than one. METHODS The study design was a retrospective cohort study set in the Tayside region of Scotland (population approx. 400 000). Participants were residents of Tayside from 1 January 1993 until 31 December 1995 with at least 12 months of prescriptions of oral hypoglycaemic drugs (OHDs). The main outcome measures were adherence indices for sulphonylureas and metformin separately, adjusting for prescribing while hospitalized. RESULTS Of the total 2920 subjects identified, adequate adherence (> or = 90%) was found in 31% of those prescribed sulphonylureas alone (n = 1329, median adherence = 300 days per year), and in 34% of those prescribed metformin alone (n = 528, median = 302 days per year). There were significant linear trends of poorer adherence with each increase in the daily number of tablets taken (p = 0.001) and increase in co-medication (p = 0.0001) for sulphonylureas alone after adjustment for other factors. CONCLUSIONS In the community only one in three with Type 2 diabetes had adequate adherence to OHDs. One tablet per day administration was associated with greater adherence than multiple tablets. Poor adherence is a major obstacle to the benefit of complex drug regimens in the treatment of Type 2 diabetes.
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Beardon PH, McGilchrist MM, McKendrick AD, McDevitt DG, MacDonald TM. Primary non-compliance with prescribed medication in primary care. BMJ (CLINICAL RESEARCH ED.) 1993; 307:846-8. [PMID: 8401129 PMCID: PMC1678870 DOI: 10.1136/bmj.307.6908.846] [Citation(s) in RCA: 238] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To determine the rate of patients not redeeming their prescriptions (primary noncompliance) and assess the factors influencing this. DESIGN Observational study comparing copies of prescriptions written by general practitioners with those dispensed by pharmacists and subsequent case record review. SETTING A large rural general practice in Tayside. SUBJECTS All 4854 patients who received prescriptions (20,921) written between January 1989 and March 1989. MAIN OUTCOME MEASURES The rate of non-redemption of prescriptions. RESULTS Seven hundred and two patients (14.5%) did not redeem 1072 (5.2%) prescriptions during the study period, amounting to 11.5% of men and 16.3% of women. Non-redemption was highest in women aged 16-29 (27.6% of women) and men aged 40-49 (18.3% of men). Of prescriptions issued to women for oral contraceptives 24.8% were not redeemed during the study period. In those who redeemed prescriptions 17% were not exempt from prescription charges compared with 33% of patients who failed to redeem them. The non-redemption rate was highest for prescriptions issued at the weekends, although this was a small proportion of all prescribing. Prescriptions issued by trainee general practitioners were also less likely to be redeemed. CONCLUSIONS Non-redemption varies with age, sex, general practitioner, exemption status, and with day of the week the prescription was written. Observational studies of drug exposure can be more accurately estimated from dispensing rather than prescribing data.
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MacDonald TM, Morant SV, Robinson GC, Shield MJ, McGilchrist MM, Murray FE, McDevitt DG. Association of upper gastrointestinal toxicity of non-steroidal anti-inflammatory drugs with continued exposure: cohort study. BMJ (CLINICAL RESEARCH ED.) 1997; 315:1333-7. [PMID: 9402773 PMCID: PMC2127829 DOI: 10.1136/bmj.315.7119.1333] [Citation(s) in RCA: 219] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES To determine the profile of risk of upper gastrointestinal toxicity during continuous treatment with, and after cessation of, non-steroidal anti-inflammatory drugs. DESIGN Cohort study with a prospectively constructed, population based, record linkage database containing details of exposure to all community dispensed non-steroidal anti-inflammatory drugs and also all admissions to hospital for upper gastrointestinal diagnoses. SETTING The population of Tayside, Scotland. SUBJECTS 52,293 subjects aged 50 and over who received one or more non-steroidal anti-inflammatory between 1 January 1989 and 31 December 1991 and 73,792 subjects who did not receive one during the same period (controls). MAIN OUTCOME MEASURES Admission to hospital for upper gastrointestinal bleeding and perforation, and admission for other upper gastrointestinal diagnoses. RESULTS About 2% of the non-steroidal anti-inflammatory cohort were admitted with an upper gastrointestinal event during the study period compared with 1.4% of controls. The risk of admission for upper gastrointestinal haemorrhage and perforation was constant during continuous non-steroidal anti-inflammatory exposure and carried over after the end of exposure. The results were similar for admissions for all upper gastrointestinal events. CONCLUSION This study provides evidence that non-steroidal anti-inflammatory toxicity persists with continuous exposure. There seems to be carryover toxicity after the end of prescribing. These findings have implications for the management of patients requiring non-steroidal anti-inflammatory drugs.
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Wei L, Wang J, Thompson P, Wong S, Struthers AD, MacDonald TM. Adherence to statin treatment and readmission of patients after myocardial infarction: a six year follow up study. Heart 2002; 88:229-33. [PMID: 12181210 PMCID: PMC1767352 DOI: 10.1136/heart.88.3.229] [Citation(s) in RCA: 211] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To investigate patients' adherence to statin treatment prescribed following their first myocardial infarction (MI) and to estimate the effect of adherence to statins on recurrence of MI and all cause mortality. DESIGN Cohort study using a record linkage database. SETTING Tayside, Scotland, UK. PATIENTS Patients who experienced their first MI between January 1990 and November 1995. MAIN OUTCOME MEASURES Percentage of statin use and adherence to statins by patients after an MI and the relative risk of hospitalisation for recurrent MI. The effect of adherence on all cause mortality was also examined. The covariates used were age, sex, socioeconomic deprivation, serum cholesterol concentration, diabetes mellitus, cardiovascular drug use, and other hospitalisations. RESULTS Of 5590 patients who experienced an incident MI, 717 (12.8%) experienced at least one further MI. Only 7.7% of patients used statins after an MI during the study period. Compared with those not taking statins, those who had 80% or better adherence to statin treatment had an adjusted relative risk of recurrent MI of 0.19 (95% confidence interval (CI) 0.08 to 0.47) and all cause mortality of 0.47 (95% CI 0.22 to 0.99). There was no significant reduction in either end point for those who were less than 80% adherent to statins. CONCLUSIONS Despite the infrequent use of statin during the study period, good adherence to statin treatment was associated with lower risk of recurrent MI.
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Tzemos N, Lim PO, MacDonald TM. Nebivolol reverses endothelial dysfunction in essential hypertension: a randomized, double-blind, crossover study. Circulation 2001; 104:511-4. [PMID: 11479245 DOI: 10.1161/hc3001.094207] [Citation(s) in RCA: 210] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Vascular endothelial dysfunction may predict future atherosclerosis. Hence, an antihypertensive agent that reverses endothelial dysfunction and lowers blood pressure might improve the prognosis of patients with hypertension. We hypothesized that nebivolol, a vasodilating beta-blocker, could improve endothelial dysfunction. We tested this hypothesis by comparing the effects of nebivolol and atenolol on endothelial function. METHODS AND RESULTS Twelve hypertensive patients with a mean ambulatory blood pressure of 154+/-7/97+/-10 mm Hg were randomized after a 2-week placebo run-in period (baseline) in a double-blind, crossover fashion to 8-week treatment periods with either 5 mg of nebivolol with 2.5 mg of bendrofluazide or 50 mg of atenolol with 2.5 mg of bendrofluazide. Forearm venous occlusion plethysmography and intra-arterial infusions of acetylcholine and N(G)-monomethyl-L-arginine (L-NMMA) were used to assess stimulated and basal endothelium-dependent nitric oxide release, respectively. Sodium nitroprusside was used as an endothelium-independent control. Nebivolol/bendrofluazide and atenolol/bendrofluazide each lowered the clinic blood pressure to the same extent (132+/-7/82+/-6 and 132+/-9/83+/-8 mm Hg, respectively; P<0.001 from baseline). The vasodilatory response to acetylcholine was significantly increased with nebivolol/bendrofluazide (maximum percentage change in forearm blood flow [mean+/-SEM], 435+/-27%, P<0.001) but not with atenolol/bendrofluazide. Similarly, the endothelium-dependent vasoconstrictive response to L-NMMA was significantly improved only with nebivolol treatment (percentage change in forearm blood flow, -54+/-5%; P<0.001). The response to sodium nitroprusside was not different between treatments, suggesting that the endothelium-independent pathway was unaffected. CONCLUSIONS Nebivolol/bendrofluazide increased both stimulated and basal endothelial nitric oxide release, whereas for the same degree of blood pressure control, atenolol/bendrofluazide had no effect on nitric oxide bioactivity. Thus, nebivolol may offer additional vascular protection in treating hypertension.
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Clinical Trial |
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Morris AD, Boyle DI, MacAlpine R, Emslie-Smith A, Jung RT, Newton RW, MacDonald TM. The diabetes audit and research in Tayside Scotland (DARTS) study: electronic record linkage to create a diabetes register. DARTS/MEMO Collaboration. BMJ (CLINICAL RESEARCH ED.) 1997; 315:524-8. [PMID: 9329309 PMCID: PMC2127363 DOI: 10.1136/bmj.315.7107.524] [Citation(s) in RCA: 200] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
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.
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Comparative Study |
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Mackenzie IS, Morant SV, Bloomfield GA, MacDonald TM, O'Riordan J. Incidence and prevalence of multiple sclerosis in the UK 1990-2010: a descriptive study in the General Practice Research Database. J Neurol Neurosurg Psychiatry 2014; 85:76-84. [PMID: 24052635 PMCID: PMC3888639 DOI: 10.1136/jnnp-2013-305450] [Citation(s) in RCA: 199] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To estimate the incidence and prevalence of multiple sclerosis (MS) by age and describe secular trends and geographic variations within the UK over the 20-year period between 1990 and 2010 and hence to provide updated information on the impact of MS throughout the UK. DESIGN A descriptive study. SETTING The study was carried out in the General Practice Research Database (GPRD), a primary care database representative of the UK population. MAIN OUTCOME MEASURES Incidence and prevalence of MS per 100 000 population. Secular and geographical trends in incidence and prevalence of MS. RESULTS The prevalence of MS recorded in GPRD increased by about 2.4% per year (95% CI 2.3% to 2.6%) reaching 285.8 per 100 000 in women (95% CI 278.7 to 293.1) and 113.1 per 100 000 in men (95% CI 108.6 to 117.7) by 2010. There was a consistent downward trend in incidence of MS reaching 11.52 per 100 000/year (95% CI 10.96 to 12.11) in women and 4.84 per 100 000/year (95% CI 4.54 to 5.16) in men by 2010. Peak incidence occurred between ages 40 and 50 years and maximum prevalence between ages 55 and 60 years. Women accounted for 72% of prevalent and 71% of incident cases. Scotland had the highest incidence and prevalence rates in the UK. CONCLUSIONS We estimate that 126 669 people were living with MS in the UK in 2010 (203.4 per 100 000 population) and that 6003 new cases were diagnosed that year (9.64 per 100 000/year). There is an increasing population living longer with MS, which has important implications for resource allocation for MS in the UK.
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Evans JM, McMahon AD, Murray FE, McDevitt DG, MacDonald TM. Non-steroidal anti-inflammatory drugs are associated with emergency admission to hospital for colitis due to inflammatory bowel disease. Gut 1997; 40:619-22. [PMID: 9203940 PMCID: PMC1027164 DOI: 10.1136/gut.40.5.619] [Citation(s) in RCA: 190] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND To evaluate the relation between non-steroidal anti-inflammatory drugs (NSAIDs) and colitis due to inflammatory bowel disease. METHODS A case-control study was conducted using a prospectively constructed, record linkage database containing hospital event and dispensed drug data (1989-93). The study population consisted of 319,465 people resident in Tayside in January 1989, and still resident (or dead) in October 1994. RESULTS Of the 785 patients admitted to hospital as emergencies with colitis between July 1989 and June 1993, 200 fulfilled the case criterion of colitis due to inflammatory bowel disease. A further 1198 persons were used as community controls. Odds ratios were calculated for three exposure periods (current, recent, and past exposure). The overall odds ratios (with 95% confidence intervals) for current and recent exposure to NSAIDs were 1.77 (1.01 to 3.10) and 1.93 (1.20 to 3.09) respectively. Current and recent exposure to NSAIDs was also associated for incident cases, with odds ratios of 2.96 (1.32 to 6.64) and 2.51 (1.13 to 5.55). There was a trend for recent exposure among non-incident cases. CONCLUSION The use of NSAIDs may be associated with an increased risk of emergency admission to hospital for colitis due to inflammatory bowel disease, particularly among patients with no previous history.
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research-article |
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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: 6.9] [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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Lim PO, Dow E, Brennan G, Jung RT, MacDonald TM. High prevalence of primary aldosteronism in the Tayside hypertension clinic population. J Hum Hypertens 2000; 14:311-5. [PMID: 10822317 DOI: 10.1038/sj.jhh.1001013] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
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.
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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: 5.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Letter |
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Nolan J, Flapan AD, Capewell S, MacDonald TM, Neilson JM, Ewing DJ. Decreased cardiac parasympathetic activity in chronic heart failure and its relation to left ventricular function. BRITISH HEART JOURNAL 1992; 67:482-5. [PMID: 1622699 PMCID: PMC1024892 DOI: 10.1136/hrt.67.6.482] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Activation of the sympathetic nervous system has been extensively studied in patients with chronic heart failure, but the parasympathetic nervous system has received relatively little attention. The objective in this study was to investigate cardiac parasympathetic activity in chronic heart failure and to explore its relation to left ventricular function. METHODS Heart rate variability was measured from 24 hour ambulatory electrocardiograms by counting the number of times each RR interval exceeded the preceding RR interval by more than 50 ms (counts). This method provided a sensitive index of cardiac parasympathetic activity. RESULTS Mean (range) of counts were: waking 48 (1-275)/h, sleeping 62 (0-360)/h, and total 1310 (31-7278)/24 h. These were lower than expected, and in 26 (60%) of the 43 patients counts fell below the lower 95% confidence intervals (95% CI) for RR counts in normal subjects. A significant correlation between total 24 hour RR counts and left ventricular ejection fraction was present (r = 0.49, p less than 0.05). CONCLUSIONS These results indicate that most patients with chronic heart failure have reduced heart rate variability and therefore reduced cardiac parasympathetic activity. The degree of parasympathetic dysfunction is related to the severity of left ventricular dysfunction. This may be relevant to the high incidence of ventricular arrhythmias and poor prognosis of patients with chronic heart failure.
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Abstract
PURPOSE Use of the aldosterone-to-renin ratio (ARR) has suggested that at least one in 10 hypertensive subjects have primary aldosteronism (PA). There is thus a timely need to review the literature for effective drug therapies and to speculate on other therapeutic options by taking into account recent advances in understanding of the PA disease pathophysiological process. DATA SOURCE A MEDLINE and EMBASE search of all articles published from the start of the databases until July 1999 and reviews of the bibliographies of textbooks. STUDY SELECTION Primary research articles on the medical treatment of PA with emphasis on diagnosis, treatment option, drug dosage, therapeutic response and adverse drug effect. DATA EXTRACTION Study design and quality were assessed. Relevant data on diagnostic methodology, drug usage and response were analysed and compared. DATA SYNTHESIS A select number of subjects with aldosterone-producing adenoma (APA) can be expected to respond well to surgical treatment For the majority of PA cases especially subjects with idiopathic hyperaldosteronism (IHA), long-term medical treatment is now safe and feasible although no randomized controlled trials have been carried out to date. The best therapeutic response is obtained by directly antagonizing aldosterone at the receptor level using medium to low dose spironolactone and this response can be predicted by a raised ARR. The response to other potassium-sparing diuretics and calcium channel blockers are modest. IHA responds better than angiotensin II-unresponsive APA to angiotensin converting enzyme inhibitors and this may also be true with angiotensin II receptor blockers. The discovery of the aldosterone synthase gene opens up the possibility for gene therapy. CONCLUSION The diagnosis of PA allows appropriate management with resultant blood pressure control in many hypertensive subjects who otherwise have resistant hypertension despite multiple drug therapy.
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Review |
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Morris AD, McAlpine R, Steinke D, Boyle DI, Ebrahim AR, Vasudev N, Stewart CP, Jung RT, Leese GP, MacDonald TM, Newton RW. 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. Diabetes Care 1998; 21:738-43. [PMID: 9589233 DOI: 10.2337/diacare.21.5.738] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
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.
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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: 4.3] [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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MacDonald TM, Walker SP, Hannan NJ, Tong S, Kaitu'u-Lino TJ. Clinical tools and biomarkers to predict preeclampsia. EBioMedicine 2022; 75:103780. [PMID: 34954654 PMCID: PMC8718967 DOI: 10.1016/j.ebiom.2021.103780] [Citation(s) in RCA: 111] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/01/2021] [Accepted: 12/10/2021] [Indexed: 11/04/2022] Open
Abstract
Preeclampsia is pregnancy-specific, and significantly contributes to maternal, and perinatal morbidity and mortality worldwide. An effective predictive test for preeclampsia would facilitate early diagnosis, targeted surveillance and timely delivery; however limited options currently exist. A first-trimester screening algorithm has been developed and validated to predict preterm preeclampsia, with poor utility for term disease, where the greatest burden lies. Biomarkers such as sFlt-1 and placental growth factor are also now being used clinically in cases of suspected preterm preeclampsia; their high negative predictive value enables confident exclusion of disease in women with normal results, but sensitivity is modest. There has been a concerted effort to identify potential novel biomarkers that might improve prediction. These largely originate from organs involved in preeclampsia's pathogenesis, including placental, cardiovascular and urinary biomarkers. This review outlines the clinical imperative for an effective test and those already in use and summarises current preeclampsia biomarker research.
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Review |
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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: 108] [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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Evans JM, McMahon AD, McGilchrist MM, White G, Murray FE, McDevitt DG, MacDonald TM. Topical non-steroidal anti-inflammatory drugs and admission to hospital for upper gastrointestinal bleeding and perforation: a record linkage case-control study. BMJ (CLINICAL RESEARCH ED.) 1995; 311:22-6. [PMID: 7613317 PMCID: PMC2550082 DOI: 10.1136/bmj.311.6996.22] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To evaluate the relation between topically applied non-steroidal anti-inflammatory drugs and upper gastrointestinal bleeding and perforation. DESIGN A case-control study with 1103 patients admitted to hospital for upper gastrointestinal bleeding or perforation between January 1990 and December 1992 (cases). Two different control groups were used, with six community controls and with two hospital controls for each case. Previous exposure to topical and oral non-steroidal anti-inflammatory drugs and ulcer healing drugs was assessed. STUDY POPULATION The population of 319,465 people who were resident in Tayside and were registered with a Tayside general practitioner between January 1989 and October 1994. A record linkage database containing all data on hospital events and dispensed drugs between 1989 and 1992 was used for this population. MAIN OUTCOME MEASURES Unadjusted and adjusted odds ratios of exposure in those admitted to hospital compared with controls. RESULTS Significant unadjusted associations were detected between all three classes of drug and upper gastrointestinal complications. The significant association detected for topical non-steroidal anti-inflammatory drugs was no longer evident in analyses which adjusted for the confounding effect of concomitant exposure to oral anti-inflammatories and ulcer healing drugs (odds ratio = 1.45; 95% confidence interval 0.84 to 2.50 with community controls; 1.06; 0.60 to 1.88 with hospital controls). CONCLUSION In this study topical non-steroidal anti-inflammatory drugs were not significantly associated with upper gastrointestinal bleeding and perforation after adjustment for the confounding effects of concomitant use of oral anti-inflammatories and ulcer healing drugs.
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Flynn RWV, MacDonald TM, Morris AD, Jung RT, Leese GP. The thyroid epidemiology, audit, and research study: thyroid dysfunction in the general population. J Clin Endocrinol Metab 2004; 89:3879-84. [PMID: 15292321 DOI: 10.1210/jc.2003-032089] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
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.
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Struthers AD, Donnan PT, Lindsay P, McNaughton D, Broomhall J, MacDonald TM. Effect of allopurinol on mortality and hospitalisations in chronic heart failure: a retrospective cohort study. Heart 2002; 87:229-34. [PMID: 11847159 PMCID: PMC1767024 DOI: 10.1136/heart.87.3.229] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/14/2001] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To examine whether allopurinol is associated with any alteration in mortality and hospitalisations in patients with chronic heart failure (CHF). This hypothesis is based on previous data that a high urate concentration is independently associated with mortality with a risk ratio of 4.23 in CHF. DESIGN Retrospective cohort study. SETTING Medicines Monitoring Unit, Ninewells Hospital, Dundee, UK. PATIENTS 1760 CHF patients divided into four groups: those on no allopurinol, those on long term low dose allopurinol, those on short term low dose allopurinol, and those on long term high dose allopurinol. MAIN OUTCOME MEASURES Total mortality, cardiovascular mortality, cardiovascular hospitalisations, cardiovascular mortality or hospitalisations. RESULTS Long term low dose allopurinol was associated with a significant worsening in mortality over those who never received allopurinol (relative risk 2.04, 95% confidence interval (CI) 1.48 to 2.81). This may be because low dose allopurinol is insufficient to negate the adverse effect of a high urate concentration. However, long term high dose (> or = 300 mg/day) allopurinol was associated with a significantly better mortality than longstanding low dose allopurinol (relative risk 0.59, 95% CI 0.37 to 0.95). This may mean that high dose allopurinol can fully negate the adverse effect of urate and return the mortality to normal. CONCLUSIONS Long term high dose allopurinol may be associated with a better mortality than long term low dose allopurinol in patients with CHF because of a dose related beneficial effect of allopurinol against the well described adverse effect of urate. Further work is required to substantiate or refute this finding.
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Abstract
PURPOSE To review information on exercise testing in hypertensive patients and persons at risk for developing hypertension and to determine whether this type of investigation is valuable for diagnosis, prognosis, or assessment of the effect of therapy. DATA SOURCES A MEDLINE search of English-language articles published between 1985 and 1995 and reviews of the bibliographies of textbooks. STUDY SELECTION Primary research articles on exercise testing in patients with hypertension, with an emphasis on methods, diagnosis, prognosis, and assessment of drug therapy. DATA EXTRACTION Study design and quality were assessed, with particular attention paid to methods and aims. Relevant data on hemodynamic responses in hypertensive patients and persons at risk for developing hypertension and correlations to end-organ damage, mortality, and exercise tolerance were analyzed. DATA SYNTHESIS The exercise capacity of hypertensive patients was found to be reduced by as much as 30% compared with age-matched controls. This exercise impairment increases with age and end-organ damage, and its origin can be traced back to adolescence. Total peripheral resistance also progressively increases. These changes are caused by functional and structural involvement of the cardiovascular system. Diastolic dysfunction of the heart is a prominent factor in this exercise limitation. The blood pressure responses to exercise have prognostic value for the future development of hypertension, end-organ damage, and death. The adequacy of antihypertensive treatment should therefore be evaluated in terms of normalizing these stress-related blood pressure responses. CONCLUSION Exercise testing is a simple procedure that has great potential for assessing hypertensive patients. More research is necessary, however, to determine whether controlling blood pressure during exercise is beneficial.
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Review |
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MacDonald TM, Morant SV, Goldstein JL, Burke TA, Pettitt D. Channelling bias and the incidence of gastrointestinal haemorrhage in users of meloxicam, coxibs, and older, non-specific non-steroidal anti-inflammatory drugs. Gut 2003; 52:1265-70. [PMID: 12912856 PMCID: PMC1773795 DOI: 10.1136/gut.52.9.1265] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Although clinical trial results suggest that meloxicam has less gastrointestinal toxicity than most other non-steroidal anti-inflammatory drugs (NSAIDs), in practice it has been associated with a large number of yellow card reports of gastrointestinal complications. AIMS To estimate whether meloxicam and the coxibs, rofecoxib and celecoxib, have been channelled towards high risk patients, and to estimate the risk of hospitalisation for gastrointestinal haemorrhage associated with the use of these drugs, allowing for the effects of channelling. PATIENTS Using the UK General Practice Research Database, this study included 7.1 thousand patient years (tpy) exposure to meloxicam, 1.6 tpy exposure to coxibs, and 628 tpy exposure to older non-specific NSAIDs. METHODS Cohort study of patients who received a prescription for an NSAID between June 1987 and January 2001. Exposure to newer NSAIDs (meloxicam, rofecoxib, celecoxib) and to older non-specific NSAIDs was identified. Channelling was assessed on factors including: demographic variables; diagnosis of arthritis; history of NSAID use or gastrointestinal events, including gastrointestinal haemorrhage; and use of ulcer healing drugs. RESULTS Most risk factors for gastrointestinal haemorrhage were more prevalent among patients prescribed the newer NSAIDs. Adjusting for these risk factors reduced the relative risks of gastrointestinal haemorrhage on meloxicam and coxibs versus older non-specific NSAIDs to 0.84 (95% confidence interval 0.60, 1.17) and 0.36 (0.14, 0.97), respectively. CONCLUSIONS Channelling towards high risk gastrointestinal patients occurred in the prescribing of newer NSAIDs. After attempting to correct for channelling bias, coxib exposure, but not meloxicam exposure, was associated with a significantly lower risk of gastrointestinal haemorrhage than older non-specific NSAID exposure.
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