Do H2-receptor antagonists cause acute pancreatitis?

The aim of this study was to investigate the association between H(2)-receptor antagonists and acute pancreatitis. The automated database of the Medicines Monitoring Unit (MEMO) was used to carry out a case-control study, supplemented with information on possible confounding factors from hospital and GP medical records. Cases were patients hospitalized with a computerized diagnosis of acute pancreatitis, and two sets of controls were drawn from (1) the study population and from (2) the same GP practice as the case. Current or 60-day exposure to cimetidine and ranitidine was analysed. In adjusted analyses, cimetidine exposure and ranitidine exposure were associated with an increased risk of hospitalization for acute pancreatitis, as were alcohol abuse and cholelithiasis. The risks were lower in unadjusted analyses, suggesting that the association is confounded, although they did not disappear completely. A possible explanation is that data on confounding were incomplete. This study cannot discount the existence of an association between H(2)-antagonists and acute pancreatitis, and highlights the difficulties involved in obtaining complete and accurate data on confounding factors that are not collected routinely.

Misclassification and selection bias in case-control studies using an automated database

Automated databases are increasingly being used for pharmacoepidemiological research and fieldwork is often carried out to supplement and validate information held within them. In MEMO's case-control studies, patients are identified using computerized ICD9 diagnosis codes, the original medical records are retrieved and checked, and only patients fulfilling case inclusion criteria are used. The 20-30% of patients for whom medical records cannot be found are usually excluded. The aim is to eliminate misclassification bias. However, selection bias may be introduced if availability of medical records is associated with exposure. This investigation was therefore carried out to assess the relative importance of misclassification and selection bias. Data from four previous case-control studies, investigating the associations between NSAIDs and hospitalization for colitis, acute renal failure, appendicitis and colorectal cancer, were used. To assess misclassification, odds ratios (with 95% CI) for recent exposure to NSAIDs were compared in repeated studies that used all patients identified by ICD9 codes, with studies using validated cases only. Selection bias was assessed by comparing results in studies using patients for whom records could and could not be found. Results were plotted and the graphs indicated that misclassification bias was relatively unimportant, but that selection bias could be introduced into a study in this way.

Treatment of steal syndrome complicating a proximal arteriovenous bridge graft fistula by simple distal artery ligation without revascularization using intraoperative pressure measurements

This case report describes the treatment of a patient with a steal syndrome complicating a brachioaxillary prosthetic bridge graft AV fistula by simple ligation of the brachial artery beyond the fistula. Intraoperative pressure measurements showed concomitant distal revascularization to be unnecessary.

Inhibition of bacterial IF2 binding to fMet-tRNA((fMet)) by aminoglycosides

Screening for inhibitors of bacterial protein synthesis Initiation Factor 2 (IF2) binding to N-formyl-Methionyl-transfer RNA (fMet-tRNA((fMet))) identified a series of aminoglycosides, that included amikacin and kanamycin A1, as inhibitors of this interaction. Subsequent testing revealed that aminoglycosides displayed a wide range of inhibitory activity. However, the failure of these compounds to completely inhibit binding of IF2 to fMet-tRNA((fMet)), the known ability of aminoglycosides to bind RNA, and the ability of the aminoglycosides to displace PicoGreen bound to fMet-tRNA((fMet)) suggest these compounds act by binding fMet-tRNA((fMet)). This hypothesis is further supported by isothermal denaturation experiments that failed to show any interaction between the IF2 protein and the aminoglycosides.

Gender differences in autonomic cardiovascular regulation: spectral, hormonal, and hemodynamic indexes

The autonomic nervous system drives variability in heart rate, vascular tone, cardiac ejection, and arterial pressure, but gender differences in autonomic regulation of the latter three parameters are not well documented. In addition to mean values, we used spectral analysis to calculate variability in arterial pressure, heart rate (R-R interval, RRI), stroke volume, and total peripheral resistance (TPR) and measured circulating levels of catecholamines and pancreatic polypeptide in two groups of 25 +/- 1.2-yr-old, healthy men and healthy follicular-phase women (40 total subjects, 10 men and 10 women per group). Group 1 subjects were studied supine, before and after beta- and muscarinic autonomic blockades, administered singly and together on separate days of study. Group 2 subjects were studied supine and drug free with the additional measurement of skin perfusion. In the unblocked state, we found that circulating levels of epinephrine and total spectral power of stroke volume, TPR, and skin perfusion ranged from two to six times greater in men than in women. The difference (men > women) in spectral power of TPR was maintained after beta- and muscarinic blockades, suggesting that the greater oscillations of vascular resistance in men may be alpha-adrenergically mediated. Men exhibited muscarinic buffering of mean TPR whereas women exhibited beta-adrenergic buffering of mean TPR as well as TPR and heart rate oscillations. Women had a greater distribution of RRI power in the breathing frequency range and a less negative slope of ln RRI power vs. ln frequency, both indicators that parasympathetic stimuli were the dominant influence on women's heart rate variability. The results of our study suggest a predominance of sympathetic vascular regulation in men compared with a dominant parasympathetic influence on heart rate regulation in women.

Hypersensitivity reactions associated with exposure to naproxen and ibuprofen: a cohort study

The aim of the study was to evaluate the risks of hospitalisation and death due to hypersensitivity reactions associated with the NSAIDs naproxen and ibuprofen, using a record-linkage database for Tayside, Scotland (population 400,000). Cohorts of patients exposed to naproxen (n=54,038) and ibuprofen (n=79,513) were assembled. There were no deaths due to hypersensitivity. There was an increased risk of unvalidated hypersensitivity reactions during periods on-drug versus off-drug in patients exposed to naproxen and ibuprofen. However, after checking medical records, none of the three valid cases of hypersensitivity in the naproxen cohort and neither of the two in the ibuprofen cohort were judged to be due to NSAID exposure. A "worst-case" scenario gave an adjusted rate-ratio of on-drug with naproxen versus on-drug with ibuprofen of 1.63 (0.50, 5.29). The study shows that hypersensitivity reactions associated with NSAID use are rare, and provides no evidence that the risks of hypersensitivity reactions differ between naproxen and ibuprofen.

Pharmacoepidemiological research at the Medicines Monitoring Unit, Scotland: data protection and confidentiality

The Medicines Monitoring Unit (MEMO) is a University-based organization that uses record-linkage techniques to construct an observational database for the population of Tayside, Scotland (approximately 400,000 people). This contains healthcare data indexed by a unique identifier, including data on all prescriptions dispensed, which facilitates pharmacoepidemiological (and other) research. It has hitherto been possible to carry out drug safety studies in the entire population, with access to original medical records of patients where necessary, that have satisfied ethical concerns and confidentiality legislation. However, the recent UK Data Protection Act 1998 (which enforces the 1995 European Directive on Data Protection) has important implications for MEMO's research. The Act has necessitated changes to the way in which research studies are carried out, with MEMO's objective being to ensure that research can continue while protecting the rights and privacy of individual patients. This involves anonymization of data, seeking specific ethical approval for research studies and obtaining relevant permissions from 'Caldicott Guardians', as described in this article.

Sodium phenoxyacetate hemihydrate

The structure of the hemihydrate of sodium phenoxyacetate, Na(+) x C(8)H(7)O(3)(-) x 0.5H(2)O, has been redetermined at low temperature (160 K). The structure consists of ribbons containing octahedral NaO(6) units, and half of the Na(2)O(2) squares within the ribbon are bridged by water molecules which lie across twofold rotation axes in C2/c. The phenyl substituents lie on the outside of the ribbon.

Epinephrine, vasodilation and hemoconcentration in syncopal, healthy men and women

Healthy young people may become syncopal during standing, head up tilt (HUT) or lower body negative pressure (LBNP). To evaluate why this happens we measured hormonal indices of autonomic activity along with arterial pressure (AP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) and measures of plasma volume. Three groups of normal volunteers (n = 56) were studied supine, before and during increasing levels of orthostatic stress: slow onset, low level, lower body negative pressure (LBNP) (Group 1), 70 degrees head up tilt (HUT) (Group 2) or rapid onset, high level, LBNP (Group 3). In all groups, syncopal subjects demonstrated a decline in TPR that paralleled the decline in AP over the last 40 s of orthostatic stress. Ten to twenty seconds after the decline in TPR. HR also started to decline but SV increased, resulting in a net increase of CO during the same period. Plasma volume (PV, calculated from change in hematocrit) declined in both syncopal and nonsyncopal subjects to a level commensurate with the stress, i.e. Group 3 > Group 2 > Group 1. The rate of decline of PV, calculated from the change in PV divided by the time of stress, was greater (p < 0.01) in syncopal than in nonsyncopal subjects. When changes in vasoactive hormones were normalized by time of stress, increases in norepinephrine (p < 0.012, Groups 2 and 3) and epinephrine (p < 0.025, Group 2) were greater and increases in plasma renin activity were smaller (p < 0.05, Group 2) in syncopal than in nonsyncopal subjects. We conclude that the presyncopal decline in blood pressure in otherwise healthy young people resulted from declining peripheral resistance associated with plateauing norepinephrine and plasma renin activity, rising epinephrine and rising blood viscosity. The increased hemoconcentration probably reflects increased rate of venous pooling rather than rate of plasma filtration and, together with cardiovascular effects of imbalances in norepinephrine, epinephrine and plasma renin activity may provide afferent information leading to syncope.

Adrenergic blockade reduces skeletal muscle glycolysis and Na(+), K(+)-ATPase activity during hemorrhage

BACKGROUND

Recent evidence suggests that hyperlactatemia in shock may reflect accelerated aerobic glycolysis linked to activity of the Na(+), K(+)-ATPase rather than hypoxia. Epinephrine stimulates glycolysis in resting muscle largely by stimulating Na(+), K(+)-ATPase activity. This study evaluates the effects of hemorrhagic shock, with and without combined alpha- and beta-adrenergic receptor blockade, on lactate production, glycogenolysis, Na(+)-K(+) pump activity, and high-energy phosphates in rat skeletal muscle.

METHODS

Male Sprague-Dawley rats in four treatment groups were studied: unhemorrhaged control not receiving blockers (CN), controls receiving blockers (CB), shocked animals not receiving blockers (SN), and shocked rats receiving blockers (SB). Shocked rats (SN and SB) were bled to a MAP of 40 mm Hg, maintained for 60 min. Blocker groups (CB and SB) received propranolol and phenoxybenzamine. Arterial blood was drawn for plasma lactate, epinephrine, norepinephrine, and gas analysis. Lactate, glycogen, glucose 6-phosphate, ATP, phosphocreatine, and intracellular Na(+) and K(+) were determined in extensor digitorum longus and soleus muscles. For comparison, muscles were exposed to epinephrine and/or ouabain in vitro.

RESULTS

With the exception of P(a)CO(2), HCO(3), and base excess in the SN group, no significant differences in arterial blood gas parameters were noted. Adrenergic blockade significantly reduced plasma lactate concentration. In shocked rats, adrenergic blockade significantly reduced muscle lactate and glucose 6-phosphate accumulation. Intracellular Na(+):K(+) ratio was decreased in SN rats, implying increased Na(+)-K(+) pump activity. Adrenergic blockade raised the intracellular Na(+):K(+) ratio in shocked animals, implying decreased pump activity. Epinephrine exposure in vitro stimulated muscle lactate production, raised glucose 6-phosphate content, and significantly reduced soleus phosphocreatine stores.

CONCLUSIONS

Neither hypoxia nor defective oxidative metabolism appeared responsible for increased glycolysis during hemorrhagic shock. Adrenergic blockade concurrently reduced plasma lactate, muscle levels of lactate and glucose 6-phosphate, and muscle Na(+)-K(+) pump activity during shock. Rapid skeletal muscle aerobic glycolysis in response to increased plasma epinephrine levels may be an important contributor to increased glycolysis in muscle and increased plasma lactate during hemorrhagic shock.

Record-linkage methodology for prescribing research

Record-linkage refers to the linking together of data relating to the same individual from separate source files. In this paper, we discuss ways in which the technique can enhance observational prescribing research in large populations. We draw upon the work of the Medicines Monitoring Unit (MEMO), University of Dundee, to illustrate its contribution to prescribing research.

Contraindications to metformin therapy in patients with Type 2 diabetes--a population-based study of adherence to prescribing guidelines

AIMS

To define the number of people in Tayside, Scotland (population 349 303) with Type 2 diabetes who use metformin, the incidence of contraindications to its continued use in these people and the proportion that discontinued metformin treatment following the development of a contraindication.

METHODS

Retrospective cohort study of the incidence of contraindications to metformin in all patients with Type 2 diabetes using metformin from January 1993 to June 1995. The contraindications of acute myocardial infarction, cardiac failure, renal impairment and chronic liver disease were identified by: the regional diabetes information system, biochemistry database and hospital admissions database and a database of all encashed community prescriptions.

RESULTS

One thousand eight hundred and forty seven subjects (26.3% of those with Type 2 diabetes) redeemed prescriptions for metformin. Of these, 3.5% were admitted with an acute myocardial infarction (71 episodes); 4.2% were admitted with cardiac failure (114 episodes); 21.0% received metformin and loop diuretics for cardiac failure concurrently; 4.8% developed renal impairment; and 2.8% developed chronic liver disease. The development of contraindications rarely resulted in discontinuation of metformin, for example only 17.5% and 25% stopped metformin after admission with acute myocardial infarction and development of renal impairment, respectively. In total, 24.5% of subjects receiving metformin, 6.4% of all people with Type 2 diabetes, had contraindications to its use. There was one episode of lactic acidosis in 4600 patient years.

CONCLUSIONS

This population-based study shows that 24.5% of patients prescribed metformin have contraindications to its use. Development of contraindications rarely results in discontinuation of metformin therapy. Despite this, lactic acidosis remains rare. Diabet. Med. 18, 483-488 (2001)

Glaucoma incidence in an unselected cohort of diabetic patients: is diabetes mellitus a risk factor for glaucoma? DARTS/MEMO collaboration. Diabetes Audit and Research in Tayside Study. Medicines Monitoring Unit

AIMS

To evaluate whether diabetes mellitus is a risk factor for the development of primary open angle glaucoma or ocular hypertension (OHT).

METHODS

A historical cohort study of an unselected population comprising all residents of the Tayside region of Scotland was performed using record linkage techniques followed by case note review. Ascertainment of prevalent diabetes was achieved using the Diabetes Audit and Research in Tayside Study (DARTS) validated regional diabetes register. Glaucoma and treated OHT were defined by encashment of community prescriptions and the statutory surgical procedure coding database.

RESULTS

The study population comprised 6631 diabetic subjects and 166 144 non-diabetic subjects aged >40 years without glaucoma or OHT at study entry. 65 patients with diabetes and 958 without diabetes were identified as new cases of glaucoma or treated OHT during the 24 month study period, yielding a standardised morbidity ratio of 127 (95% CI, 96-158). Case note review demonstrated non-differential misclassification of prevalent glaucoma and OHT as incident disease (diabetic cohort 20%, non-diabetic cohort 24%; p=0.56) primarily as a result of non-compliance in medically treated disease. Removing misclassified cases and adjusting for age yielded an incidence of primary open angle glaucoma in diabetes of 1.1/1000 patient years (95% CI, 0.89-1. 31) compared to 0.7/1000 patient years (95% CI, 0.54-0.86) in the non-diabetic cohort; RR 1.57 (95% CI, 0.99-2.48).

CONCLUSIONS

This study failed to confirm an association between diabetes mellitus and primary open angle glaucoma and ocular hypertension. A non-significant increase in diagnosed and treated disease in the diabetic population was observed, but evidence was also found that detection bias contributes to this association.

Continuous-Wave and Passively Mode-Locked Operation of a Cunyite (Cr(4+):Ca(2)GeO(4)) Laser

Continuous-wave and mode-locked Cr(4+):Ca(2)GeO(4) lasers that use a fiber laser pump source were demonstrated. The continuous-wave Cr(4+):Ca(2)GeO(4) laser yielded a maximum output power of 415 mW at 1420 nm and a tuning range of 1335-1492 nm. With a saturable-absorber mirror, 60-ps pulses and 110-mW maximum output power were generated from a passively mode-locked Cr(4+):Ca(2)GeO(4) laser.

Polymyalgia rheumatica and giant cell arteritis

PMR and GCA are related conditions that seem to represent a continuum of disease. These conditions are relatively common and seem to be mediated by a cellular inflammatory response. Increasing evidence suggests an infectious cause (or causes) precipitating this immune response in genetically susceptible individuals. Whereas previously thought to affect primarily branch vessels of the aortic arch, GCA is now thought of as a disease in which proximal aortic involvement is frequent. Despite the potential for serious, even fatal complications, overall prognosis for patients with GCA or PMR is excellent. Corticosteroids remain the standard treatment, although not curative. Whereas the ESR is a useful indicator of disease activity, other markers which may be more precise such as creative protein and Il-6 seem to offer added information about disease activity.

Report of a rotavirus outbreak in an adult nursing home population

Rotavirus is a double-stranded RNA enteric virus that is the most important cause of severe, dehydrating diarrhea in infants and young children worldwide. Symptoms range from mild diarrhea to a life-threatening illness. Rotavirus occasionally afflicts adult members of the infected infant's family, geriatric patients, and immunocompromised hosts. We report the outbreak of rotavirus infection in a large nursing home facility.

REPORT

In September 1996, 19 residents and 15 staff members of a 64-bed nursing home facility began to develop an acute, febrile illness associated with vomiting and diarrhea. The Public Health Service conducted an outbreak investigation. The infection displayed fecal-to-oral transmission with an incubation period of 1 to 2 days. The median duration of illness was 3 days for residents and 1 day for staff members. One resident died as a result of illness complications. Stool antigen tests from five residents and two employees were positive for rotavirus. Infection control policies were reevaluated, and interventions to arrest the outbreak were undertaken. The employee sick leave policy was strictly enforced. Education seminars were held, with employees reinforcing the concepts of enteric isolation and proper handwashing techniques. Surfaces and objects in the dining area were disinfected with a weak chloride solution. Once these measures were implemented, the rotavirus outbreak was contained.

CONCLUSION

Rotavirus is a common cause of infectious diarrhea that can afflict the geriatric population. When infection occurs in a nursing home facility, rapid transmission can develop and morbidity can result. Nursing home infection control policies need to be evaluated constantly and new measures need to be implemented should an outbreak of rotavirus occur.

A comparison of Cunyite and Fosterite NIR tunable laser tissue welding using native collagen fluorescence imaging

OBJECTIVE

To evaluate the technique of native collagen fluorescence imaging for assessing the extent of welded areas for tissues exposed to different near-infrared (NIR) laser wavelengths.

BACKGROUND

Native fluorescence imaging may be used to identify the distribution of collagen and elastin in tissues. Our past work demonstrated that different welding strengths were obtained under the same laser power conditions using different NIR wavelengths. The role of collagen in tissue welding experiments is not well understood.

METHODS

Two new NIR tunable lasers were used to weld canine skin. The welded areas on the surface and in cross sections were analyzed by measuring the spatial distribution of native collagen fluorescence at 380 nm excited by 340 nm radiation.

RESULTS

The results show that native collagen fluorescence imaging is a useful technique for analyzing the extent of tissue welds produced under a range of laser exposures. Fluorescence imaging reveals the depth of laser interaction with the tissue as well as evaluating collateral damage to the tissue surface. The welded volume obtained in skin using Cunyite laser exposure at 1,430 nm is deeper than that produced with Forsterite laser exposure at 1,250 nm. The post welded tensile strength for the same power density is greater for the Cunyite lasers. Ablated tissue on the surface is more prevalent with Forsterite laser welding at 1,250 nm than with Cunyite at 1,430 nm.

CONCLUSION

Native collagen fluorescence can distinguish between tissue welds that have been produced by different NIR wavelengths. Tissue welding using 1,430 nm radiation is more effective than that using 1,250 nm.

Socio-economic status, obesity and prevalence of Type 1 and Type 2 diabetes mellitus

AIMS

The influence of socio-economic status on the prevalence of Type 1 and Type 2 diabetes mellitus, and on obesity, was explored using routinely collected healthcare data for the population of Tayside, Scotland.

METHODS

Among 366,849 Tayside residents, 792 and 5,474 patients with Type 1 and Type 2 diabetes, respectively, were identified from a diabetes register. The Carstairs Score was used as a proxy for socio-economic status. This is a material deprivation measure derived from the UK census, using postcode data for four key variables. Odds ratios for diabetes prevalence, adjusted for age, were determined for each of six deprivation categories (1 - least deprived, 6/7 - most deprived). The mean body mass index (BMI) in each group was also determined, and the effect of deprivation category explored by analysis of covariance, adjusting for age and sex.

RESULTS

The prevalence of Type 2 diabetes, but not Type 1 diabetes, varied by deprivation. People in deprivation category 6 and 7 were 1.6-times (95% confidence interval 1.4-1.8) more likely to have Type 2 diabetes than those least deprived. There was no relationship between deprivation and BMI in Type 1 diabetes (P = 0.36), but there was an increase in BMI with increasing deprivation in Type 2 diabetes (P < 0.001; test of linearity P < 0.001).

CONCLUSIONS

The study confirms the relationship between deprivation and the prevalence of Type 2 diabetes. There are more obese, diabetic patients in deprived areas. They require more targeted resources and more primary prevention.

Impact of type 1 and type 2 diabetes on patterns and costs of drug prescribing: a population-based study

OBJECTIVE

Utilization and costs of prescription drugs were investigated in diabetic and nondiabetic patients.

RESEARCH DESIGN AND METHODS

The study was carried out in Tayside, Scotland, U.K. A validated population-based diabetes register was used to identify patients with type 1 and type 2 diabetes, and a database of all prescriptions dispensed in the community was used to investigate drug utilization in 1995.

RESULTS

In a population of 406,526, there were 974 (0.2%) with type 1 diabetes and 6,869 (1.7%) with type 2 diabetes. The mean dispensed prescribing rates for all drugs (excluding antidiabetic medication) were higher across all age-groups for diabetic patients. After adjusting for age, patients with type 1 diabetes were 2.07 times (95% CI 2.03-2.11) more likely and patients with type 2 diabetes were 1.70 times (1.69-1.71) more likely to be dispensed a drug item than people without diabetes. This likelihood was increased in every drug category, even those not directly related to diabetes, and the proportion and cost of drug items dispensed to diabetic patients was therefore higher than expected given the prevalence of diabetes. Upon projecting these results to the U.K. population, it was discovered that nearly 8% of the U.K. drug budget (Pound Sterling 350 million) is accounted for by patients with diabetes (90% of that by patients with type 2 diabetes).

CONCLUSIONS

This study highlights the increased usage and cost of prescription drugs in diabetes, with type 2 diabetes constituting a particular burden. It was discovered that 1.4% of drug usage in the entire population can be accounted for by the increased prescribing rate of diabetic patients compared with that of nondiabetic patients.

Treatment of giant cell arteritis: interleukin-6 as a biologic marker of disease activity

OBJECTIVE

To determine the value of the erythrocyte sedimentation rate (ESR) and plasma interleukin-6 (IL-6) as biologic markers for monitoring disease activity in giant cell arteritis (GCA).

METHODS

Twenty-five patients with biopsy-proven GCA were enrolled into a prospective treatment study. Therapy was initiated with prednisone, 60 mg/day, followed by a predetermined tapering schedule. Patients were monitored monthly for clinical signs of active vasculitis and laboratory parameters indicative of inflammation, including elevated ESR (>30 mm/hour) and elevated plasma IL-6 concentrations (>6.1 pg/ml).

RESULTS

Upon initiation of corticosteroid treatment, clinical signs of GCA disappeared in all patients; however, 60% of the patients developed symptoms of recurrent disease, on 1 or more occasions, while the prednisone dosage was being reduced. These 31 disease flares diagnosed over 550 days were associated with symptoms of systemic inflammation but did not result in vascular complications. The ESR was elevated in 76% of the patients prior to initiation of treatment (median 65 mm/hour) and normalized by day 28 of therapy (median 6 mm/hour). The median ESR remained in the normal range during the followup period. Plasma IL-6 levels, which were abnormal in 92% of untreated patients (median 16 pg/ml), were partially responsive to the initial high doses of corticosteroids by day 28 (median 6 pg/ml), but levels did not completely normalize with continued therapy. Elevation of the ESR was seen during only 58% of all disease flares, but 89% of disease recurrences were associated with increased plasma IL-6 levels (P = 0.03).

CONCLUSION

Plasma IL-6 is more sensitive than ESR for indicating disease activity in untreated and treated GCA patients. Standard corticosteroid regimens only partially suppress vascular inflammation. Smoldering disease activity may expose GCA patients to the risk of progressive vascular disease (e.g., formation of aortic aneurysms) and chronic systemic complications such as IL-6-mediated osteopenia.

Suicide among nursing home residents: a population-based study

OBJECTIVE

The rate of suicide is highest among the oldest old and is associated with chronic medical illness and functional impairment. These risk factors are prevalent among nursing home (NH) residents, yet little has been published on suicide in this population.

METHODS

We performed a population-based, retrospective cohort study to identify clinical features of NH residents attempting or completing suicide. A computerized data-base search was conducted to identify cases of completed suicide in Olmsted County and surrounding communities (846 NH beds) between 1981 and 1997. Subjects' medical records were reviewed to identify clinical details.

RESULTS

Five cases of completed suicide and three suicide attempts were identified, including six men and two women. Deaths were the result of drowning, hanging, or medication overdose (the latter following a period of intentional hoarding). Those who died ranged in age from 69 to 87 years. Most had been NH residents for less than 6 months. No deaths occurred in patients with severe cognitive impairment.

CONCLUSIONS

Suicide and suicide attempts in the NH seem to be uncommon but are likely underrecognized and underreported. Suicide risk among NH residents seems to be highest among men and those recently admitted to facilities. In addition, suicide methods differ among NH residents compared with community-dwelling older people, likely reflecting environmental restrictions and physical limitations. Suicide and suicide attempts are important resident health issues and risk management concerns for staff in long-term-care facilities.

False positive head-up tilt: hemodynamic and neurohumoral profile

OBJECTIVES

This study examined differences in mechanisms of head-up tilt (HUT)-induced syncope between normal controls and patients with neurocardiogenic syncope.

BACKGROUND

A variable proportion of normal individuals experience syncope during HUT. Differences in the mechanisms of HUT-mediated syncope between this group and patients with neurocardiogenic syncope have not been elucidated.

METHODS

A 30-min 80 degrees HUT was performed in eight HUT-negative volunteers (Group I), eight HUT-positive volunteers (Group II) and 15 patients with neurocardiogenic syncope. Heart rate and blood pressure (BP) were monitored continuously. Epinephrine and norepinephrine plasma levels, as well as left ventricular dimensions and contractility determined by echocardiography, were measured at baseline and at regular intervals during the test.

RESULTS

The main findings of this study were the following: 1) All parameters were similar at baseline in the three groups; and 2) During tilt: a) the time to syncope was shorter in Group III than in group II (9.5 +/- 3 vs. 17 +/- 3 min p < 0.05); b) there was an immediate, persisting drop in mean BP in Group III; c) the decrease rate of left ventricular end-diastolic dimensions was greater in Group III than in Group II or Group I (-1.76 +/- 0.42 vs. -0.87 +/- 0.35 and -0.67 +/- 0.29 mm/min, respectively, p < 0.05); d) the leftventricular shortening fraction was greater in Group III than in the other two groups (39 +/- 1 vs. 34 +/- 1 and 32 +/- 1%, respectively, p < 0.05); and e) although the norepinephrine level remained comparable among the groups, there was a significantly higher peak epinephrine level in Group III than in Group II and Group I (112.3 +/- 34 vs. 77.6 +/- 10 and 65 +/- 12 pg/ml, p < 0.05).

CONCLUSIONS

Mechanisms of syncope during HUT appeared to be different in normal volunteers and patients with neurocardiogenic syncope. In the latter, there was evidence of an impaired vascular resistance response from the beginning of the orthostatic challenge. Furthermore, in the patients there was more rapid peripheral blood pooling, as indicated by the echocardiographic measurements of left ventricular end-diastolic changes, leading to more precocious symptoms. In syncopal patients, the higher level of plasma epinephrine probably mediated the increased cardiac contractility and possibly contributed to the impaired vasoconstrictive response.

Infant sleep position: A telephone survey of inner-city parents of color

OBJECTIVE

To assess what positions parents were placing their infants to sleep and their opinion about sleep positioning.

DESIGN

A prospective telephone survey of parents of 2-month-old infants with repeated measures at 4 months that began during the second wave of the Back to Sleep campaign in 1994.

PARTICIPANTS

African-American, Hispanic, Asian, and American Indian parents from inner cities in the north central United States.

RESULTS

Preference for prone positioning existed at both 2 and 4 months (over 40%). Twenty-four percent of parents disagreed with the recommendations of the American Academy of Pediatrics regarding supine or lateral positioning.

CONCLUSIONS

Although prone sleep positioning has decreased over the past 5 years, many inner-city parents of color prefer this over supine. The Back to Sleep campaign appears effective in changing attitudes and medical personnel appear influential in promoting risk reductions associated with sudden infant death syndrome. More efforts are clearly needed to convince parents who disagree with and resist recommendations.sleep, infants, SIDS, African-Americans, Back to Sleep (campaign).

Frequency of blood glucose monitoring in relation to glycaemic control: observational study with diabetes database

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.

Elder mistreatment

Elder mistreatment is a widespread problem in our society that is often under-recognized by physicians. As a result of growing public outcry over the past 20 years, all states now have abuse laws that are specific to older adults; most states have mandated reporting by all health care professionals. The term "mistreatment" includes physical abuse and neglect, psychologic abuse, financial exploitation and violation of rights. Poor health, physical or cognitive impairment, alcohol abuse and a history of domestic violence are some of the risk factors for elder mistreatment. Diagnosis of elder mistreatment depends on acquiring a detailed history from the patient and the caregiver. It also involves performing a comprehensive physical examination. Only through awareness, a healthy suspicion and the performing of certain procedures are physicians able to detect elder mistreatment. Once it is suspected, elder mistreatment should be reported to adult protective services.

Corticosteroid requirements in polymyalgia rheumatica

BACKGROUND

Polymyalgia rheumatica (PMR) is a systemic inflammatory disease of unknown cause that affects older individuals. Clinical symptoms respond promptly to corticosteroids, but treatment is often required for several years, frequently resulting in adverse drug effects. Guidelines for the optimal use of corticosteroids that maximize relief of symptoms but minimize adverse effects of the therapy are needed.

OBJECTIVE

To determine whether clinical or laboratory parameters in PMR could be identified that allow for stratifying patients into subsets with differences in corticosteroid requirements.

PATIENTS AND METHODS

We studied 27 patients with PMR treated with a standardized schedule of prednisone. Patients were reevaluated at monthly intervals for pain scores and physician and patient assessments. Plasma interleukin 6 level and the erythrocyte sedimentation rate were measured at each visit. The duration of steroid therapy and the cumulative steroid dose were calculated.

RESULTS

Based on the initial response to therapy and the duration of disease, the 27 patients could be subdivided into 3 distinct groups. Eight with low erythrocyte sedimentation rates responded rapidly and required corticosteroids for less than 1 year with rare disease flares on tapering of prednisone. Twelve others responded well initially but did not tolerate reduction to lower doses and had remitting disease of more than 1 year. Seven patients had only a partial response to the initial steroid regimen. After 4 weeks of therapy, the erythrocyte sedimentation rates improved, but levels of interleukin 6 remained elevated. Pretreatment pain scores were also higher in these partial responder patients (P = .05).

CONCLUSIONS

Polymyalgia rheumatica is a heterogeneous disease with variations in the treatment duration and dose of corticosteroids required for suppression of symptoms. Pretreatment erythrocyte sedimentation rate and nonresponsiveness of interleukin 6 to steroid therapy are helpful in dividing patients into subsets with different treatment requirements.

Identification of (-)-cis-6-acetyl-4S-(3-chloro-4-fluoro-benzoylamino)- 3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran-3S-ol as a potential antimigraine agent

Optimisation of novel cis- and trans-4-(substituted-amido)benzopyran-3-ol derivatives has led to the identification of SB-220453 20 with an in vivo pre-clinical CNS profile predictive of potential antimigraine activity.

Congestive heart failure in the community: trends in incidence and survival in a 10-year period

OBJECTIVE

To compare the incidence of congestive heart failure and the survival in patients with congestive heart failure in Rochester, Minn, in 1981 with that observed in 1991.

METHODS

Population-based, descriptive epidemiological study with ecological and individual level comparisons over time. Olmsted County, Minnesota, where the Rochester Epidemiology Project provides passive surveillance of the population for health outcomes. All 248 patients fulfilled the Framingham criteria, 107 patients presenting with the new onset of congestive heart failure in 1981 and 141 patients in 1991. The community inpatient and outpatient medical records of all incident cases were reviewed to evaluate the presenting characteristics of patients at diagnosis.

RESULTS

The incidence of congestive heart failure after adjustment for age and sex to the US population was not significantly different in the 1991 cohort compared with that in 1981 (3.0 per 1000 person-years; 95% confidence interval, 2.5-3.5 vs 2.8 per 1000 person-years; 95% confidence interval, 2.2-3.3; P = .55). The survival of patients with new diagnosis of congestive heart failure was similar in the 2 cohorts (P = .53). Survival adjusted for age, sex, and New York Heart Association functional class was not significantly different in patients with congestive heart failure in 1981 and 1991 (relative risk, 0.907; P = .55).

CONCLUSIONS

These data suggest that recent advances in management of cardiovascular disease, as used in the community, had not yet impacted incidence or survival of patients with congestive heart failure in the community during the 10-year study period. This highlights the need to continue efforts to ensure that advances in diagnosis and therapy are incorporated into the care of patients with congestive heart failure in the community.

Record-linkage for pharmacovigilance in Scotland

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.

Use of echocardiography in the management of congestive heart failure in the community

OBJECTIVES

We evaluated the use and the impact of echocardiography in patients receiving an initial diagnosis of congestive heart failure in Olmsted County, Minnesota, in 1991.

BACKGROUND

The American College of Cardiology/American Heart Association clinical practice guidelines recommend echocardiography in all patients with suspected congestive heart failure. No data are available on use and impact of echocardiography in management of congestive heart failure in a community.

METHODS

The medical records linkage system of the Rochester Epidemiology Project was used to identify all 216 patients who satisfied the Framingham criteria for congestive heart failure. Of these, 137 (63%) underwent echocardiography within 3 weeks before or after the episode of congestive heart failure (Echo group), and the other 79 patients constitute the No-Echo group.

RESULTS

The No-Echo group patients were older (p=0.022), were more likely to be female (p=0.072), had milder symptoms (p=0.001) and were less often hospitalized at diagnosis (p=0.001). Fewer patients in the No-Echo group were treated with angiotensin-converting enzyme inhibitors (p=0.001). Advanced age (> or = 80 years), lower New York Heart Association functional class, absence of a fourth heart sound on examination, absence of cardiomegaly or signs of congestive heart failure on chest radiography and absence of known valve disease were independently related to the decision not to obtain an echocardiogram. Survival after adjustment for age, functional class and gender was lower in the No-Echo group than the Echo group (risk ratio=0.607, p=0.017).

CONCLUSIONS

The underuse of echocardiography appears to be associated with poorer survival and underuse of angiotensin-converting enzyme inhibitor therapy.

Congestive heart failure in the community: a study of all incident cases in Olmsted County, Minnesota, in 1991

BACKGROUND

Data are limited regarding the classification and prognosis of patients with congestive heart failure (CHF) in the community.

METHODS AND RESULTS

Using the resources of the Rochester Epidemiology Project, we evaluated all patients receiving a first diagnosis of CHF in Olmsted County, Minnesota, in 1991 (n=216). Among these patients, 88% were >/=65 years and 49% were >/=80 years of age. The prognosis of patients with a new diagnosis of CHF was poor; survival was 86+/-2% at 3 months, 76+/-3% at 1 year, and 35+/-3% at 5 years. Of the 216 patients, 137 (63%) had an assessment of ejection fraction. In these patients, systolic function was preserved (ejection fraction >/=50%) in 59 (43%) and reduced (ejection fraction <50%) in 78 (57%). Survival adjusted for age, sex, NYHA class, and coronary artery disease was not significantly different between patients with preserved and those with reduced systolic function (relative risk, 0.80; P=0.369). ACE inhibitors were used in only 44% of the total population with CHF.

CONCLUSIONS

The present study reports the clinical characteristics and natural history of CHF as it presents in the community in the vasodilator era. CHF is a disease of the "very elderly," frequently occurs in the setting of normal ejection fraction, and has a poor prognosis, regardless of the level of systolic function. Diagnostic and therapeutic methods are underused in the community.

Kilohertz Cr:forsterite regenerative amplifier

We report on a tunable regenerative amplifier that is operational in the near-infrared spectral region from 1230 to 1280 nm based on the vibronic laser material Cr:forsterite. Utilizing the technique of chirped-pulse amplification, we generated pulses as short as 150 fs at 1255 nm at a repetition rate of 1 kHz. Pulse amplification of more than 5 x 10(5) times was observed, with recorded output pulse energies of 34 muJ . Implementation of a second-harmonic generator yielded 110-fs-duration pulses of 7-muJ energy at 625 nm.

Aspirin, nonsteroidal anti-inflammatory drugs, and epistaxis. A regional record linkage case control study

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.

Polymyalgia rheumatica and giant cell arteritis

Giant cell (temporal) arteritis and polymyalgia rheumatica are related conditions that primarily affect older persons. They are among the most common chronic inflammatory disorders in this age group. In recent years, several new insights have been gained about the clinical features of these illnesses as well as their underlying pathophysiology. In addition, a great deal of study is underway to find better ways of detecting, monitoring, and treating them. This article provides a general review of these conditions, including their diagnosis and treatment.

Two-dimensional near-infrared transillumination imaging of biomedical media with a chromium-doped forsterite laser

Transillumination images of objects hidden in normal and cancerous human breast tissues and bovine, porcine, and gallinaceous (chicken) tissues as well as model-random-scattering media were recorded with 1250-nm light from a chromium-doped forsterite laser. A Fourier space gate and a polarization gate were used to sort out image-bearing photons and discriminate against multiply scattered image-blurring photons. Better contrast, higher spatial resolution, and deeper penetration of samples were achieved for imaging with 1250-nm light than those obtained at shorter wavelengths, such as 1064 nm from a neodymium-doped yttrium aluminum garnet (YAG) laser. Better contrast and higher resolution were also obtained when the object was imaged through normal human breast tissue than through cancerous breast tissue. Images with marked distinction between fatty and fibrous human breast tissues were obtained when the Cr:forsterite laser was tuned to 1225 nm, a wavelength that resonates with an optical absorption band of breast fat tissues. Imaging with linearly polarized light revealed that the image quality depends significantly on the orientation of the polarization of the incident light with respect to the fibers in the bovine tissue.

Drug exposure risk windows and unexposed comparator groups for cohort studies in pharmacoepidemiology

AIM

To determine the appropriate size of risk windows in both exposed and unexposed sub-cohorts.

METHOD

Data was taken from a previous study of upper gastrointestinal haemorrhage and perforation. The length of each prescription for NSAIDs was estimated. The risk was calculated for the duration of a prescription plus increments of -30, -25,..., +115, +120 (i.e. 31 increments). Ten unexposed groups were re-sampled for each increment (stratified for age and sex), using the same lengths of risk window as the exposed group. Mean risks and rate-ratios were calculated (per thousand person-years).

RESULTS

The NSAID risk rose from 3.52 at -30 days to a peak of 5.82 at -15 days, and then decreased gradually to 2.83 at +120 days. Unexposed risk was variable for the negative increments, and decreased gradually from 2.16 at +0 days to 1.54 at +120 days. The rate-ratio rose from 1.55 at -30 days to a peak of 2.85 at -5 days, and then decreased to 1.85 at +120 days.

CONCLUSION

Risk windows should be the same as (or slightly less than) the calculated length of a prescription. Lengthy windows should not be used for unexposed comparator groups (the exposed windows may be randomly allocated).

The radiodensity of medications seen on x-ray films

OBJECTIVE

To analyze the radiodensity of commonly used medications and determine their ability to be seen on plan x-ray films.

MATERIAL AND METHODS

Under conditions intended to simulate a patient undergoing radiography of the abdomen (including the use of a patient-equivalent phantom), 50 prescription and nonprescription drugs were tested. Their radiodensities were quantified, and their visibility on plain x-ray films was noted. The study drugs were then ranked in order of decreasing radiodensity. In addition, we report an illustrative case of ingested pills in the stomach that mimicked gallstones, a phenomenon we termed "pseudogallstones".

RESULTS

In a 71-year-old woman with upper abdominal pain and nausea, a presumptive diagnosis of gallstones based on x-ray findings was subsequently found to be retained iron tablets. This case prompted our assessment of the radiodensity of medications frequently prescribed for elderly patients. Although all 50 medications studied were visible on plain x-ray films, a 13-fold difference was found in their relative radiodensities. Of the medications studied, potassium chloride was the most radiodense, and prednisone was the least radiodense. As a group, minerals were the most radiodense of all medications studied.

CONCLUSION

Numerous commonly prescribed medications in their undissolved, undigested state are visible on plain x-ray films, as are mineral supplements, which have high radiodensities. At times, the appearance of these medications and supplements may be confused with organic pathologic conditions.

Relation of colonic transit to functional bowel disease in older people: a population-based study

OBJECTIVE

The pathophysiology underlying chronic constipation in older people is poorly understood. Our objective was to determine if functional bowel disease (particularly constipation) in this population is associated with risk factors (age, immobility, low dietary fiber intake, and medication use) or directly with slow colonic transit.

METHODS

A previously validated questionnaire was administered to a random sample of older residents (age range 65-104 years, n = 1609) of Olmsted County, MN. A random subset who met standard diagnostic criteria for functional constipation (n = 52) or irritable bowel syndrome (IBS) (n = 55) and a group without gastrointestinal symptoms (n = 93) were selected for further study. Each subject underwent structured interview and physical examination. Total caloric and fiber intake were assessed by dietitian interview, a food frequency questionnaire, and a food diary. Physical activity was assessed using a previously validated instrument. Medication use was determined by self-report, physician interview, and review of medical records. Total and segmental colonic transit was assessed radiographically using radioopaque markers.

RESULTS

Total colonic transit times were prolonged in subjects with functional constipation (median 50.4 hours) but not in subjects with IBS (median 34.2 hours) or in healthy controls (median 28.8 hours); however, only rectosigmoid transit was delayed significantly. Age, gender, physical activity, and dietary fiber intake were not associated with total transit times, nor could they discriminate among the three patient groups. Laxative use was associated with prolonged total transit times independent of patient group.

CONCLUSIONS

Older subjects can be classified by abdominal pain and bowel symptoms, which reflect colonic transit times. Older subjects with constipation symptoms generally have prolonged rectosigmoid transit. Other potential risk factors do not distinguish symptom subgroups, nor are they associated with altered colonic transit although older people who use laxatives regularly have prolonged colonic transit.

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

OBJECTIVE

To evaluate the association between the use of ACE inhibitors and hospital admission for severe hypoglycemia and to explore the effects of potential confounding variables on this relationship.

RESEARCH DESIGN AND METHODS

The association between the use of ACE inhibitors and the incidence of hypoglycemia is controversial. A recent study reported that 14% of all hospital admissions for hypoglycemia might be attributable to ACE inhibitors. We performed a nested case-control study, using a cohort of 6,649 diabetic patients taking insulin or oral antidiabetic drugs, on the Diabetes Audit and Research in Tayside, Scotland (DARTS) database. From 1 January 1993 to 30 April 1994, we identified 64 patients who had been admitted to Tayside hospitals with hypoglycemia and selected 440 control patients from the same cohort.

RESULTS

Hypoglycemia was associated with the use of ACE inhibitors (odds ratio [OR] 3.2, 95% CI 1.2-8.3, P = 0.023), whereas use of beta-blockers and calcium antagonists was not associated with an increased risk of hospitalization for hypoglycemia with ORs of 0.9 (95% CI 0.3-3.3) and 1.7 (95% CI 0.2-2.1), respectively. There were significant differences between case and control patients in type of diabetes treatment, diabetes duration, place of routine diabetes care, and congestive cardiac failure. These differences did not confound the relationship between ACE inhibitors and hypoglycemia (adjusted OR 4.3, 95% CI 1.2-16.0).

CONCLUSIONS

The results show that the association between ACE inhibitor therapy and hospital admission for severe hypoglycemia is not explained by these confounding factors. Although ACE inhibitors have distinct advantages over other antihypertensive drugs in diabetes, the risk of hypoglycemia should be considered.

Characterization of the binding of [3H]-SB-204269, a radiolabelled form of the new anticonvulsant SB-204269, to a novel binding site in rat brain membranes

1. SB-204269 (trans-(+)-6-acetyl-4S-(4-fluorobenzoylamino)-3, 4-dihydro-2,2-dimethyl-2H-benzol[b]pyran-3R-ol, hemihydrate) shows potent anticonvulsant activity in a range of animal seizure models, with a lack of neurological or cardiovascular side-effects. The profile of the compound suggests that it may have a novel mechanism of action. This study describes the characteristics of a binding site for [3H]-SB-204269 in rat forebrain membranes. 2. Specific [3H]-SB-204269 binding was saturable and analysis indicated binding to a homogenoeous population of non-interacting binding sites with a dissociation constant (KD) of 32 +/- 1 nM and a maximum binding capacity (Bmax) of 253 +/- 18 fmol mg-1 protein. Kinetic studies indicated monophasic association and dissociation. Binding was similar in HEPES or Tris-HCl buffers and was unaffected by Na+, K+, Ca2+ or Mg2+ ions. Specific binding was widely distributed in brain, but was minimal in a range of peripheral tissues. 3. Specific [3H]-SB-204269 binding was highly stereoselective, with a 1000 fold difference between the affinities of SB-204269 and its enantiomer SB-204268 for the binding site. The affinities of analogues of SB-204269 for binding can be related to their activities in the mouse maximal electroshock seizure threshold (MEST) test of anticonvulsant action. 4. None of the standard anticonvulsant drugs, phenobarbitone, phenytoin, sodium valproate, carbamazepine, diazepam and ethosuximide, or the newer anticonvulsants, lamotrigine, vigabatrin, gabapentin and levetiracetam, showed any affinity for the [3H]-SB-204269 binding site. A wide range of drugs active at amino acid receptors, Na+ or K+ channels or various other receptors did not demonstrate any affinity for the binding site. 5. These studies indicate that SB-204269 possesses a specific CNS binding site which may mediate its anticonvulsant activity. This binding site does not appear to be directly related to the sites of action of other known anticonvulsant agents, but may have an important role in regulating neuronal excitability.

Profile of SB-204269, a mechanistically novel anticonvulsant drug, in rat models of focal and generalized epileptic seizures

1. Earlier optimization of structure-activity relationships in a novel series of 4-(benzoylamino)-benzopyrans, led to the discovery of SB-204269 (trans-(+)-6-acetyl-4S-(4-fluorobenzoylamino)-3,4-dihydro-2, 2-dimethyl-2H-benzo[b]pyran-3R-ol, hemihydrate), a potent orally-active anticonvulsant in the mouse maximal electroshock seizure threshold (MEST) test. 2. Studies have now been undertaken to determine the effects of SB-204269 in a range of seizure models and tests of neurological deficits in rats. In addition, the compound has been evaluated in a series of in vitro mechanistic assays. 3. SB-204269 proved to be an orally-effective anticonvulsant agent, at doses (0.1-30 mg Kg-1) devoid of overt behavioural depressant properties, in models of both electrically (MEST and maximal electroshock (MEST)) and chemically (i.v. pentylenetetrazol (PTZ) infusion)-evoked tonic extension seizures. However, the compound did not inhibit PTZ-induced myoclonic seizures at doses up to 30 mg kg-1, p.o. 4. SB-204269 also selectively reduced focal electrographic seizure activity in an in vitro elevated K+ rat hippocampal slice model at concentrations (0.1-10 microM) that had no effect on normal synaptic activity and neuronal excitability. 5. In all of these seizure models, SB-204269 was equivalent or better than the clinically established antiepileptic drugs carbamazepine and lamotrigine, in terms of anticonvulsant potency and efficacy. 6. Unlike SB-204269, the corresponding trans 3S,4R enantiomer, SB-204268, did not produce marked anticonvulsant effects, an observation in accord with previous findings for other related pairs of trans enantiomers in the benzopyran series. 7. In the rat accelerating rotarod test, a sensitive paradigm for the detection of neurological deficits such as sedation and motor incoordination, SB-204269 was inactive even at doses as high as 200 mg kg-1, p.o. This was reflected in the excellent therapeutic index (minimum significantly effective dose in the rotarod test/ED50 in the MES test) for SB-204269 of > 31, as compared to equivalent values of only 7 and 13 for carbamazepine and lamotrigine, respectively. 8. At concentrations (> or = 10 microM) well above those required to produce anticonvulsant activity in vivo (i.e. 0.1 microM in brain), SB-204269 did not interact with many of the well known mechanistic targets for established antiepileptic drugs (e.g. Na+ channels or GABAergic neurotransmission). Subsequent studies have shown that the anticonvulsant properties of SB-204269 are likely to be mediated by a novel stereospecific binding site present in the CNS. 9. The overall efficacy profile in rodent seizure models, together with a minimal liability for inducing neurological impairment and an apparently unique mechanism of action, highlight the therapeutic potential of SB-204269 for the treatment of refractory partial and generalized tonic-clonic seizures.

Direct diode-pumped continuous-wave near-inf rared tunable laser operation of Cr(4+):forsterite and Cr(4+):Ca(2)GeO(4)

Continuous-wave tunable laser operation of direct diode-pumped Cr(4+):Mg(2)SiO(4) (Cr:forsterite) and Cr(4+):Ca(2)GeO(4) (cunyite) crystal were demonstrated. Diode-pumped Cr:forsterite was tunable over the 1236-1300-nm spectral range. The maximum output of 10 mW was measured at 1260 nm for 640 mW of pump power absorbed by the crystal. Diode-pumped laser operation of cunyite was also demonstrated over the 1390-1475-nm range. Free-running 20-mW output was centered at 1410 nm.

Non-steroidal anti-inflammatory drugs are associated with emergency admission to hospital for colitis due to inflammatory bowel disease

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.

No association between non-steroidal anti-inflammatory drugs and acute appendicitis in a case-control study

BACKGROUND

A recent case-control study reported an association between non-steroidal anti-inflammatory drug (NSAID) use and acute appendicitis. This association was investigated in a case-control study of patients, aged 30 years and over, admitted as an emergency to hospitals in Tayside between 1989 and 1992, who had appendicectomy for acute appendicitis.

METHODS

A record-linkage database containing records of dispensed prescriptions and hospital admissions was used. A total of 223 patients were identified. The medical records of 161 were checked, of which 138 were valid cases, and information on white cell count and NSAID exposure was recorded. Community and hospital controls were generated.

RESULTS

Some 9.0 per cent of patients were prescribed NSAIDs within 90 days of hospitalization, compared with 7.6 per cent of community controls and 11.5 per cent of hospital controls. The odds ratio was 1.21 (95 per cent confidence interval 0.73-2.01) and 0.75 (0.43-1.32) respectively. There was no significant difference in white cell count between exposed and non-exposed cases. No increased risk of appendicectomy was associated with aspirin use: odds ratio 1.67 (0.52-5.30) and 0.37 (0.12-1.13) using community and hospital controls respectively.

CONCLUSION

Appendicectomy for acute appendicitis is not associated with increased prior use of NSAIDs.

A cohort study (with re-sampled comparator groups) to measure the association between new NSAID prescribing and upper gastrointestinal hemorrhage and perforation

This cohort study examined the relationship between newly prescribed NSAIDs (none in the previous six months) and upper gastrointestinal hemorrhage and perforation in Tayside, Scotland. Exposure was classified by prescription duration. The study population consisted of the population of Tayside. A Comparator Group was chosen at random (within age and sex strata). Two hundred re-sampled comparator groups were created. Statistical analyses were carried out by Poisson regression (repeated for each of the re-samples). The analyses controlled for age, sex, prior hospitalization for upper gastrointestinal events, prior endoscopy, and the use of ulcer healing drugs. There were 78,191 subjects in the NSAID group, and 78,207 in each of the comparator groups. The increased risk with NSAIDs was only apparent for subjects without a history of upper gastrointestinal events; univariate rate ratio = 2.76 (1.90, 4.01). The final, re-sampled estimate of NSAID risk was rate ratio = 2.48 (1.87, 3.29).

Demand for warfarin anticoagulation monitoring in Tayside, Scotland

AIM

The aim of this study was to assess the demand for warfarin prescribing and monitoring, and to identify patients with atrial fibrillation who might benefit from warfarin therapy. The study was carried out in the population of Tayside, Scotland (400,000 people) using patient-specific dispensed prescribing and hospitalisation data from the Medicines Monitoring Unit at the University of Dundee.

METHODS

The incidence and prevalence of digoxin and warfarin prescribing were calculated between 1989 and 1993. Patients dispensed digoxin in 1993 were assumed to have atrial fibrillation and they were stratified into high risk groups for an adverse thromboembolic event based on past medical history. The numbers of patients at high risk who were judged to be possible candidates for warfarin were calculated.

RESULTS

The prevalence of warfarin prescribing is increasing in Tayside and is mainly for elderly patients. There were also many patients assumed to have atrial fibrillation who were at particularly high risk for an adverse thromboembolic event, who had no record of warfarin prescribing. Only 35% received warfarin. Even given the methodological limitations of this study, and the use of aspirin as an alternative prophylactic agent, it is likely that these patients have been a source of increased prevalence of warfarin prescribing since 1993 and will be in the future. Other indications for warfarin prescribing are also increasing.

CONCLUSION

It is anticipated that there will be increasing demands for anticoagulant monitoring, which will need to be met either by increasing the capacity of existing clinics, or by increasing the role of primary care.