Search PubMed⌕ Search

Biomedical subjects

A D Morris

Publications and source records attributed to A D Morris.

At least 55 records · Page 3Linked to original sources
PubMed2000

MRI scan diagnosis of trilucent breast implant rupture.

The authors present the case report of a patient who had undergone a latissimus dorsi breast reconstruction plus Trilucent implant. This patient later presented with discomfort in the breast and an MRI scan diagnosed rupture of the implant and also revealed a fluid level within the implant. These findings were confirmed at exploration and were found to be caused by separation of the contents into a serous layer and a lipid layer.

Breast Implants↗
PubMed2000

Evaluation of ethical conflicts associated with randomized, controlled trials in critically ill children.

OBJECTIVE: To determine whether randomized, controlled trials (RCTS) of potentially life-sustaining therapies in critically ill infants and children cause an ethical conflict for physician investigators and if ethical conflicts affect protocol implementation. DESIGN: Descriptive survey. SUBJECTS: A convenience sample of 1,050 physicians from a national pediatric critical care meeting mailing list. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The survey return rate was 41% (n = 415). Of the returned surveys, 81% (n = 331) were answered by pediatric intensivists and fellows. The remaining 19% (n = 84) were completed by other physician subspecialists. Overall, 74% had experience with RCTs involving a potentially life-saving therapy (25% had experience with three or more trials, and 26% had never participated in this type of study). The vast majority of the respondents (96%) indicated that they believe RCTs of potentially life-sustaining therapies are ethical; however, only 10% stated that they never experienced an ethical conflict with these types of studies. Most respondents (84%) indicated that published data from uncontrolled trials may bias them toward an investigational therapy. Furthermore, only 35% of the respondents indicated that they always maintain strict protocol adherence when the condition of a control patient deteriorates and parents request the experimental treatment. There was a significant association between physicians who experienced an ethical conflict and the likelihood that they would do the following if the condition of a control patient deteriorated: fail to maintain strict protocol adherence (p = .05); alter the protocol in response to parental requests for the experimental treatment (p < .01); or seek compassionate use of the experimental treatment (p < .01). CONCLUSIONS: Although physicians consider RCTs of potentially life-sustaining therapies ethical, they acknowledge that this type of study sometimes creates an ethical conflict. Published results of uncontrolled trials lead to investigator bias in randomized trials and preclude equipoise. Our results indicate that RCTs involving life-sustaining therapies may be biased, lack consistent protocol implementation, and raise concern that data from these studies are potentially flawed.

Bias↗
PubMed2000

Prevalence and aetiology of hypothyroidism in the young.

AIMS: To define the prevalence of hypothyroid disease in children and young people, and describe its aetiology. METHODS: We identified all patients on the Medicines Monitoring Unit (MEMO) database in the Tayside region of Scotland who had received two or more prescriptions for thyroxine during the study period (January 1993 to December 1995). Using this as a surrogate marker of hypothyroidism, we calculated the prevalence of hypothyroidism in those aged less than 22 years. Main outcome measures were prevalence of thyroxine prescription, estimated prevalence of hypothyroidism, and aetiology of the hypothyroidism (determined from case records, and biochemistry and immunology databases). RESULTS: Of 103,500 residents aged less than 22 years, 140 were identified as receiving thyroxine on prescription, giving a population prevalence of 0.135%. The ratio of male to female was 1:2.8. Acquired hypothyroidism was the commonest aetiology found in 73%, 66% of which had an autoimmune basis. The prevalence of congenital hypothyroidism was 0.027%. Seven had received treatment for malignancy (two primary thyroid). Fifteen per cent of patients had no record of secondary care follow up in Tayside. CONCLUSIONS: The overall prevalence of hypothyroidism in young people less than 22 years of age is 0.135%, and in the group aged 11-18 years it is 0.113%; these values are at least twice those of previous estimates. This suggests an increase in autoimmune thyroid disease, similar to the rising prevalence of type 1 diabetes, possibly indicating a rising incidence of autoimmunity in young people.

Adolescent↗
PubMed2000

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.

Adult↗
PubMed2000

Renal resistance to vasopressin in poorly controlled type 1 diabetes mellitus.

To investigate the hypothesis that diabetes induces nephrogenic diabetes insipidus, we studied the urine-concentrating ability in response to vasopressin (AVP) in 12 patients with insulin-dependent diabetes mellitus (IDDM) and 12 nondiabetic controls. Subjects were euglycemic-clamped, and after oral water loading, AVP was infused intravenously for 150 min. AVP induced a greater (P<0.001) rise in urine osmolality in controls (67.6+/-10.7 to 720+/-31.1 mosmol/kg, P<0.001) than in IDDM patients (64.3+/-21.6 to 516.7+/-89.3 mosmol/kg, P<0.001). Urinary aquaporin-2 concentrations after AVP infusion were higher in controls (611.8+/-105.6 fmol/mg creatinine) than in IDDM (462.0+/-94.9 fmol/mg creatinine, P = 0. 003). Maximum urine osmolality in IDDM was inversely related to chronic blood glucose control, as indicated by Hb A(Ic) (r = -0.87, P = 0.002). To test the hypothesis that improved glycemic control could reverse resistance to AVP, 10 IDDM subjects with poor glycemic control (Hb A(Ic) >9%) were studied before (B) and after (A) intensified glycemic control. Maximum urine osmolality in response to AVP increased with improved glycemic control (B, 443.8+/-49.0; A, 640.0+/-137.2 mosmol/kg, P<0.001), and urinary aquaporin-2 concentrations after AVP increased from 112.7 +/-69 to 375+/-280 fmol/mg creatinine (P = 0.006), with improved glycemic control. Poorly controlled IDDM is associated with reversible renal resistance to AVP.

Adolescent↗
PubMed2000

Allopurinol normalizes endothelial dysfunction in type 2 diabetics with mild hypertension.

Therapeutic strategies against free radicals have mostly focused on the augmentation of antioxidant defenses (eg, vitamins C and E). A novel approach is to prevent free radical generation by the enzyme system xanthine oxidase. We examined whether the inhibition of xanthine oxidase with allopurinol can improve endothelial function in subjects with type 2 diabetes and coexisting mild hypertension compared with control subjects of a similar age. We examined 23 subjects (11 patients with type 2 diabetes and 12 healthy age-matched control subjects) in 2 parallel groups. The subjects were administered 300 mg allopurinol in a randomized, placebo-controlled study in which both therapies were administered for 1 month. Endothelial function was assessed with bilateral venous occlusion plethysmography, in which the forearm blood flow responses to intra-arterial infusions of endothelium-dependent and -independent vasodilators were measured. Allopurinol significantly increased the mean forearm blood flow response to acetylcholine by 30% (3.16+/-1.21 versus 2.54+/-0.76 mL. 100 mL(-1). min(-1) allopurinol versus placebo; P=0.012, 95% CI 0.14, 1.30) but did not affect the nitroprusside response in patients with type 2 diabetes. There was no significant impact on either endothelium-dependent or -independent vascular responses in age-matched control subjects. Allopurinol improved endothelial function to near-normal levels. Regarding markers of free radical activity, the level of malondialdehyde was significantly reduced (0.30+/-0.04 versus 0. 34+/-0.05 micromol/L for allopurinol versus placebo, P=0.03) in patients with type 2 diabetes but not in control subjects. The xanthine oxidase inhibitor allopurinol improves endothelial dysfunction in patients with type 2 diabetes with mild hypertension but not in matched control subjects. In the former group, allopurinol restored endothelial function to near-normal levels.

Age Factors↗
PubMed2000

Trandolapril does not improve insulin sensitivity in patients with hypertension and type 2 diabetes: a double-blind, placebo-controlled crossover trial.

Angiotensin-converting enzyme (ACE) inhibitors are increasingly used as first-line therapy for hypertension in type 2 diabetes mellitus and are widely believed to improve insulin sensitivity (M). However, the evidence for the latter effect does not stand close scrutiny. We have assessed the effect of the ACE inhibitor trandolapril on M in 16 patients (mean +/- SD age, 58 +/- 10.6 yr) with mild-to-moderate essential hypertension (initial blood pressure, 173 +/- 14.5/93 +/- 8.0 mm Hg), obesity (body mass index, 30 +/- 5.4 kg/m2), and impaired glucose intolerance (n = 4) or type 2 diabetes (n = 12) in a double-blind, placebo-controlled crossover design. All patients underwent three 3-h euglycemic hyperinsulinemic clamp studies (soluble insulin, 1.5 mU/kg x min) after a 2-week placebo run-in and at the end of two 4-week periods of treatment with 2 mg trandolapril or placebo (2-week washout). M (mean +/- SD) did not change with trandolapril: placebo (run-in), 5.2 +/- 1.98 mg/kg x min; placebo, 5.3 +/- 1.70 mg/kg x min; trandolapril, 5.1 +/- 1.65 mg/kg x min; P = 0.58; 95% confidence intervals, -0.74, 0.43 (trandolapril vs. placebo); 95% power to exclude an 8% increase in M. In conclusion, trandolapril had no clinically relevant effect on M in patients with hypertension and type 2 diabetes. Previous reports of improved M during ACE inhibitor treatment may be attributable to suboptimal study design and/or use of surrogate measures of M.

Adult↗
PubMed2000

Hospitalizations for people with type 1 and type 2 diabetes compared with the nondiabetic population of Tayside, Scotland: a retrospective cohort study of resource use.

OBJECTIVE: To compare the hospitalizations of people with type 1 and type 2 diabetes with those of the nondiabetic population of Tayside, Scotland. RESEARCH DESIGN AND METHODS: This was a retrospective cohort study set in Tayside, Scotland. Study subjects were eligible for inclusion if they lived in Tayside from 1 January 1995 to 31 December 1995. The primary end point was hospitalization. Comparisons between people with and without diabetes were assessed using logistic regression modeling. RESULTS: The fixed population for the year 1995 included 366,849 people registered with a Tayside general practitioner; 7,735 (2.1%) of these had diabetes. Approximately 25% of all study subjects with diabetes had at least one hospital admission, compared with 12% of the nondiabetic population. The length of stay was highest for patients with type 2 diabetes (median of 7 days). People with diabetes accounted for 8.2% of the total bed days and had approximately double the risk of admission. Type 2 diabetic patients had increased risks of myocardial infarction and stroke; both type 1 and type 2 diabetic patients were at increased risk for an endocrine/metabolic admission or renal failure. The risk of ophthalmic admissions, especially for cataract, was much higher in patients with type 1 diabetes compared with the nondiabetic population. CONCLUSIONS: Type 2 diabetes was associated with more frequent and longer admissions compared with the nondiabetic population. This was due to a higher risk of neurological, cardiovascular, renal, and ophthalmic hospitalizations compared with people without diabetes.

Adult↗
PubMed2000

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.

Adolescent↗
PubMed2000

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.

Adult↗
PubMed1999

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.

Age Factors↗
PubMed1999

Exaggerated vasopressin secretion and attenuated osmoregulated thirst in human survivors of hyperosmolar coma.

AIMS/HYPOTHESIS: To test the hypothesis that subnormal thirst sensation could contribute to the development of the hypernatraemia characteristic of hyperosmolar coma, we studied osmoregulation in survivors of hyperosmolar coma. METHODS: Eight survivors of hyperosmolar coma, eight control subjects with Type II (non-insulin-dependent) diabetes mellitus and eight healthy control subjects underwent water deprivation during which measurements of thirst, plasma osmolality and vasopressin were taken. RESULTS: Water deprivation caused greater peak plasma osmolality in the hyperosmolar coma group (301.7 +/- 2.7 mmol/kg) than in Type II diabetic (294.3 +/- 3.2 mmol/kg, p < 0.01) or control group (296.9 +/- 3.0 mmol/kg, p < 0.01) and a greater increase in plasma vasopressin concentration (hyperosmolar coma, 5.8 +/- 1.3 pmol/l, Type II diabetes, 1.8 +/- 1.3 pmol/l, p < 0.001, control subjects, 2.2 +/- 1.8 pmol/l, p < 0.001). Thirst ratings were lower following water deprivation in the hyperosmolar coma group (3.5 +/- 0.8 cm) than in Type II diabetes (7.7 +/- 1.6 cm, p < 0.001) or control subjects (7.4 +/- 1.3 cm, p <0.001), and the hyperosmolar group patients drank less in 30 min following water deprivation (401 +/- 105 ml) than Type II diabetic (856 +/- 218 ml, p < 0.001) or control subjects (789 +/- 213 ml, p < 0.001). CONCLUSION/INTERPRETATION: Survivors of hyperosmolar coma have subnormal osmoregulated thirst and fluid intake, which might contribute to the hypernatraemic dehydration typical of the condition.

Aged↗
PubMed1999

Blindness in patients with diabetes who have been screened for eye disease.

PURPOSE: Detection of diabetic retinopathy by screening is a major public health concern. Fundus photography has been shown to be a useful screening tool for the detection of diabetic retinopathy. In this paper the authors assess the incidence of blind and partially sighted registration due to diabetic eye disease in patients screened by a mobile fundus photography unit and identify the factors that contributed to loss of vision in the registered group. METHODS: A retrospective review of blind and partially sighted registrations between 1990 and 1995 was performed in a diabetic population screened by a mobile fundus photography unit in a region with a population of 390,000. The incidence of blind and partially sighted registration in the screened diabetic population was calculated. In the registered group, cause of visual loss, accuracy of photograph reporting, delay in laser treatment, adequacy of laser treatment and non-attendance rates at ophthalmic clinics were assessed. RESULTS: Of the 5390 patients screened by the mobile unit over 6 years, 68 (210 per 10(5) patient-years) were registered blind or partially sighted, but in only 17 patients (53 per 10(5) patient-years) was this as a result of diabetes. The factors contributing to loss of vision were found to be failure of laser treatment, rapidly progressive disease and poor patient attendance. CONCLUSIONS: As the majority of visual impairment in patients with diabetes is not due to diabetic retinopathy, this has important implications for screening programmes and may make the St Vincent Declaration targets difficult to achieve. The rate of new blind and partially sighted registration due to diabetes in the screened population was low at 53 per 10(5) patient-years (95% confidence interval, 29-76).

Adult↗
PubMed1999

Combination treatment with methotrexate and cyclosporin for severe recalcitrant psoriasis.

An increasingly important approach to the management of patients with severe psoriasis is the concurrent use of two systemic treatments. Previous guidelines have advised against the use of methotrexate and cyclosporin in combination. We report the successful use of a combination of methotrexate and cyclosporin in the treatment of 19 patients with severe, recalcitrant psoriasis, 15 of whom had psoriatic arthropathy. Most patients had previously received two or more systemic treatments. Before combination treatment was started nine of the patients were taking methotrexate and 10 were taking cyclosporin at the maximum tolerated doses. The duration of combination treatment was bimodally distributed, with seven patients having short-term treatment (mean +/- SD duration 18. 9 +/- 15.7 weeks) and 12 patients having long-term treatment (mean +/- SD duration 193.2 +/- 160.6 weeks). Those patients who received short-term treatment did not develop any evidence of toxicity from either agent. Of those patients on long-term treatment, three developed mild impairment of renal function that returned to normal following a reduction in dose of cyclosporin, and three had impairment of renal function (following long-term cyclosporin monotherapy) that improved, but did not normalize, following a reduction in dose of cyclosporin. In each case, combination treatment for psoriasis resulted in good control of both skin and joint problems using lower doses of each agent than would have been used for monotherapy. We conclude that the combination of methotrexate and cyclosporin is an effective treatment for this group of patients.

Adult↗
PubMed1999

Advanced carpal collapse associated with congenital hypoplastic thumb.

We present the long term sequelae of two patients with congenital hypoplastic thumbs. Neither had surgical correction in childhood, but maintained adequate function in their hands. However, both have developed progressive carpal collapse in adulthood, leading to painful wrists.

Bone Diseases↗
PubMed1999

DD angiotensin-converting enzyme gene polymorphism is associated with endothelial dysfunction in normal humans.

A polymorphism within the angiotensin-converting enzyme (ACE) gene may increase the risk of myocardial infarction in individuals previously thought to be at low cardiovascular risk. The mechanism through which it exerts this effect is unknown but may be due to increased angiotensin II-induced nitric oxide (NO) breakdown and/or reduced bradykinin-mediated NO release. We investigated whether endothelial function was different between different ACE genotypes. We performed a cross-sectional study comparing the endothelial function of the 3 genotypes (II: n=25; ID: n=31; DD: n=12). Mean+/-SD ages of the subjects were 24+/-4 (II), 25+/-6 (ID), and 25+/-6 (DD) years. We assessed the impact of the genotypes on endothelial function and found that the DD genotype was associated with a significant blunting in endothelial-dependent vasodilatation (forearm blood flow data are presented as mean+/-SD ratio of blood flow in response to 3 incrementally increasing doses of each vasoactive agent in the test arm to blood flow in the control arm; the comparison is between DD versus ID versus II; the P value is an expression of an overall difference by ANOVA, and the 95% CIs are of a pairwise comparison between genotypes): acetylcholine, 2.88+/-1.45 versus 3.81+/-1.93 versus 4.23+/-2.37 (P=0.002; 95% CI [II versus ID], -0.19 to 0.91; 95% CI [II versus DD], 0.36 to 1.80; 95% CI [ID versus DD], 0.02 to 1.42). There was also a significant difference with the endothelial-independent vasodilator sodium nitroprusside, with values of 2.11+/-1.00 versus 2.55+/-1.36 versus 2.75+/-1.18 (P<0.05; 95% CI [II versus ID], -0.15 to 0.51; 95% CI [II versus DD], 0.03 to 0.89; 95% CI [ID versus DD], -0.13 to 0.71), but not with verapamil. There was no effect of the ACE genotype on endothelial-dependent or -independent vasoconstrictors NG-monomethyl-L-arginine or norepinephrine. Investigating the effects of cigarette smoking on each genotype demonstrated that for II and DD genotypes, acetylcholine responses were further blunted if subjects smoked. These data demonstrate that the DD ACE genotype in a young population is associated with a blunting of stimulated endothelial NO and donated NO responses but not to non-NO vasodilators or vasoconstrictors.

Acetylcholine↗