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Biomedical subjects

G Welch

Publications and source records attributed to G Welch.

At least 19 recordsLinked to original sources
PubMed2004

Improvements in carotid endarterectomy in Scotland: results of a national prospective survey.

BACKGROUND AND AIMS: The effectiveness of carotid endarterectomy (CEA) depends upon selection of patients with a high absolute risk of stroke, avoidance of delays from intial presentation to surgery and provsion of surgery with a low perioperative risk of stroke. We evaluated these aspects of practice in Scottish hospitals and, by encouraging adherence to national (SIGN) guidelines, attempted to improve the effectiveness of CEA. METHODS: Prospective independent survey of patient selection, pre-operative delays and surgical performance for all CEAs performed in Scottish National Health Service hospitals over two 13 month periods from September 1997 and February 1999 respectively. RESULTS: Thirteen hospitals performed 485 CEAs in the first period and 392 in the second, equating to an overall annual rate of 79 per million population. During both periods at least 95% of patients reported symptoms of carotid terittory ischaemia, but the proportion with stenoses greater than >70% rose from 89% to 97% (p<0.0001). The delays between referral, surgical consultation and subsequent surgery fell significantly but remained unacceptably long. The proportion seen by the surgeon within two weeks of referral rose from 36% to 43% (p=0.05) and the proportion operated on within one month thereafter rose from 35% to 49% (p<.0001). The perioperative combined major stroke and death rate was 3% in both periods. CONCLUSION: We demonstrated significant changes in practice, in line with national guidelines, which would be expected to improve the effectiveness of our national programme of CEA. There is further scope for improving performance, particularly in relation to pre-operative delays.

Aged↗
PubMed2003

Magnetic resonance-detected subchondral bone marrow and cartilage defect characteristics associated with pain and X-ray-defined knee osteoarthritis.

OBJECTIVE: To assess whether the presence of subchondral bone marrow abnormalities (bone marrow edema (BME)) and cartilage defects, determined by magnetic resonance imaging (MRI), would explain the difference between painful osteoarthritis of the knee (OAK) compared with painless OAK or pain without OAK. METHOD: Four groups of women (30 per group), aged 35-55 years, were recruited from the southeast Michigan Osteoarthritis cohort (group 1: painful OAK; group 2: painless OAK; group 3: knee pain without OAK; and group 4: no OAK or knee pain). OAK was defined by a Kellgren-Lawrence score of 2 or greater, while pain was based on self-report. BME and cartilage defects were identified from MRI. RESULTS: BME lesions were identified in 56% of all knees. BME lesions were four times (95% CI=1.7, 8.7) more likely to occur in the painless OAK group as compared with the group with pain, but no OAK. BME lesions >1cm were more frequent (OR=5.0; 95% CI=1.4, 10.5) in the painful OAK group than all other groups. While the frequency of BME lesions was similar in the painless OAK and painful OAK groups, there were more lesions, >1cm, in the painful OAK group. About 75% of all knees had evidence of some cartilage defect, of which 35% were full-thickness defects. Full-thickness cartilage defects occurred frequently in painful OAK. One-third of knees with full-thickness defects and 47% of knees with cartilage defects involving bone had BME >1cm. Women with radiographic OA, full-thickness articular cartilage defects, and adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than other groups (OR=3.2; 95% CI=1.3, 7.6). CONCLUSION: The finding on MRI of subchondral BME cannot satisfactorily explain the presence or absence of knee pain. However, women with BME and full-thickness articular cartilage defects accompanied by adjacent subchondral cortical bone defects were significantly more likely to have painful OAK than painless OAK.

Adult↗
PubMed2003

Responsiveness of the Problem Areas In Diabetes (PAID) questionnaire.

AIM: Responsiveness (sensitivity to change over time) is a key psychometric quality for an outcome measure. We examined the responsiveness of the Problem Areas In Diabetes (PAID) questionnaire, a measure of diabetes-specific emotional distress. METHODS: PAID data were obtained from seven diabetes intervention studies following a literature search that included both published papers and conference abstracts. To estimate responsiveness we used two indices: (i) a statistical test (the dependent t-test), and (ii) a commonly used effect size index (Cohen's d). RESULTS: Mean patient PAID scores improved from baseline to follow-up for all seven studies. Specifically, t-statistics ranged from t= 8.5 (P < 0.001) to t= 2.1 (P < 0.06). Effect size results ranged from 0.32 (i.e. small) for a disease management intervention to 0.65 (i.e. moderate) for an intensive medical/educational intervention. CONCLUSIONS: Despite the pilot nature of the studies, the pattern of findings provided strong support for the responsiveness of the PAID. Information on responsiveness helps clinical researchers select measures, accurately estimate sample size to ensure adequate statistical power, and prioritize outcomes to be assessed.

Adaptation, Psychological↗
PubMed2001

The association of menopause and physical functioning in women at midlife.

OBJECTIVES: To determine whether the characteristics of menstrual bleeding and the menopausal transition are associated with physical functioning in women age 40 to 55, after considering ethnicity, ability to pay for basics, body size, and age. DESIGN: Cross-sectional study. SETTING: Seven geographically dispersed community samples in the United States. PARTICIPANTS: The 14,427 respondents were Caucasians (46.9%), African Americans (28.7%), Chinese (4.0%), Japanese (5.3%), and Hispanics (12.6%) from the Study of Women's Health Across the Nation (SWAN) Cross-sectional Study, a study of the menopausal transition, including surgical menopause. MEASUREMENTS: The dependent variable was a three-category variable based on the physical functioning scale of the Medical Outcomes Study. Explanatory variables included menstrual and menopausal status. RESULTS: Eighty percent (80.8%) of women reported no limitation in physical functioning, whereas 10% of women had some limitation, and 9.2% of women indicated having substantial limitation. Women with substantial limitation in physical functioning had double the prevalence odds ratio (POR = 2.02; 95% confidence interval (CI) = 1.64-2.49) of having surgical menopause and 76% greater odds (POR = 1.76; 95% CI = 1.38-2.24)) of using hormones, compared with women with no limitation. Compared with those without limitation, women with substantial limitation in physical functioning had 56% greater odds (POR = 1.56; 95% CI = 1.23-1.97)) of being naturally postmenopausal and a 41% greater odds (POR = 1.41; 95% CI = 1.17-1.70) of being perimenopausal, relative to being premenopausal and after adjusting for other variables. CONCLUSION: Even at the relatively early age of 40 to 55, approximately 20% of women self-reported limitation in physical functioning. Surgical menopause and the use of hormones were more frequently observed in women with some and substantial physical limitation than in women with no limitation, even after adjusting for economic status, age, body mass index, and race/ethnicity.

Activities of Daily Living↗
PubMed2001

An X-Y paint set and sperm FISH protocol that can be used for validation of cattle sperm separation procedures.

X and Y chromosome paints were developed from sorted yak chromosomes for sexing cattle spermatozoa. Clear hybridization signals were obtained for every spermatozoon using a modified sperm decondensation protocol and fluorescence in situ hybridization (FISH). The procedure was evaluated using the established Beltsville sperm sexing technology, which separates spermatozoa by flow cytometry into X- and Y-bearing fractions. Close agreement was found between the assessment of sperm separation by flow cytometry and by FISH with the X-Y paint set. The FISH method is a simple, reliable and robust procedure for assessing the effectiveness of separation of X and Y spermatozoa.

Animals↗
PubMed1999

Glycemic control and major depression in patients with type 1 and type 2 diabetes mellitus.

The current study evaluated the association of glycemic control and major depression in 33 type 1 and 39 type 2 diabetes mellitus patients. Type 1 patients with a lifetime history of major depression showed significantly worse glycemic control than patients without a history of psychiatric illness (t = 2.09; df = 31, p < 0.05). Type 2 diabetes patients with a lifetime history of major depression did not have significantly worse control than those with no history of psychiatric illness. Findings from this study indicate different relationships between lifetime major depression and glycemic control for patients with type 1 and type 2 diabetes. Treatment implications for glycemic control in type 1 and type 2 diabetes patients are discussed.

Adult↗
PubMed1998

Distinction between symptoms of voiding and filling in benign prostatic hyperplasia: findings from the Health Professionals Follow-up Study.

OBJECTIVES: There is debate about the validity of the clinical distinction between filling and voiding symptoms of benign prostatic hyperplasia (BPH). We examined empirically the evidence for the existence of these clinical constructs. METHODS: We analyzed responses to the American Urological Association Symptom Index (AUA SI) among men from a large cohort sample (the Health Professionals Follow-up Study, n = 7753) and a subsample with physician-diagnosed BPH (n = 1856). We used factor analysis, which is a data reduction tool that allowed us to determine empirically the relationships among lower urinary tract symptoms thought to be clinically related by pathogenesis, physiology, or treatment response. RESULTS: The results of the factor analysis indicated that responses to the AUA SI items could be grouped into one of two subscales: one describing voiding problems and the other describing filling problems. Analyses of internal consistency reliability indicated that the AUA SI as well as the filling and voiding subscales have sound internal reliability. CONCLUSIONS: We found empirical support for the clinical conceptualization of lower urinary tract symptoms into filling and voiding problems. These findings provide support for using the total score on the AUA SI as a reliable measure of overall symptom severity in BPH, as well as for separately summing the voiding and filling items to measure these distinctive types of lower urinary tract symptomatology. Further research is needed to determine whether these symptom groupings better distinguish responses to one treatment type over another. If so, targeting treatment based on the relative severity of voiding and filling symptoms might improve patient outcomes.

Aged↗
PubMed1997

Reduced glutathione prevents nitric oxide-induced apoptosis in vascular smooth muscle cells.

The control of medial and neointimal growth, in which vascular smooth muscle (VSM) plays a central role, is most important to the development of hypertension and atherosclerosis, respectively. Growth of vascular smooth muscle cells is regulated by a number of factors, including the vasodilator nitric oxide (NO). In addition, NO modulates intracellular thiol redox states and the thiol redox state of the cell influences NO production. We, therefore, examined the nature of the effect of NO on growth of VSM cells and its modulation by cellular glutathione content. Here, we report that NO, either generated by NO donors or synthesized by iNOS in VSM cells, inhibited DNA synthesis and induced apoptosis in this cell type. NO-induced apoptosis was associated with a significant decrease in the intracellular concentration of reduced glutathione and with an increase in the level of the tumor suppressor gene p53 mRNA. Moreover, addition of glutathione monoethylester to the culture restored the level of reduced glutathione in VSM cells, and prevented the NO-induced increase in p53 expression and programmed cell death. Our findings suggest a role for reduced glutathione in protecting VSM cells exposed to NO from apoptosis.

Animals↗
PubMed1995

Assessment of diabetes-related distress.

OBJECTIVE: To describe a new measure of psychosocial adjustment specific to diabetes, the Problem Areas in Diabetes Survey (PAID), and to present initial information on its reliability and validity. RESEARCH DESIGN AND METHODS: Before their routine clinic appointments, 451 female patients with type I and type II diabetes, all of whom required insulin, completed a self-report survey. Included in the survey was the PAID, a 20-item questionnaire in which each item represents a unique area of diabetes-related psychosocial distress. Each item is rated on a six-point Likert scale, reflecting the degree to which the item is perceived as currently problematic. A total scale score, hypothesized to reflect the overall level of diabetes-related emotional distress, is computed by summing the total item responses. To examine the concurrent validity of the PAID, the survey also included a series of standardized questionnaires assessing psychosocial functioning (general emotional distress, fear of hypoglycemia, and disordered eating), attitudes toward diabetes, and self-care behaviors. All subjects were assessed for HbA1, within 30 days of survey completion and again approximately 1-2 years later. Finally, long-term diabetic complications were determined through chart review. RESULTS: Internal reliability of the PAID was high, with good item-to-total correlations. Approximately 60% of the subject sample reported at least one serious diabetes-related concern. As expected, the PAID was positively associated with relevant psychosocial measures of distress, including general emotional distress, disordered eating, and fear of hypoglycemia, short- and long-term diabetic complications, and HbA1, and negatively associated with reported self-care behaviors. The PAID accounted for approximately 9% of the variance in HbA1. Diabetes-related emotional distress, as measured by the PAID, was found to be a unique contributor to adherence to self-care behaviors after adjustment for age, diabetes duration, and general emotional distress. In addition, the PAID was associated with HbA1 even after adjustment for age, diabetes duration, general emotional distress, and adherence to self-care behaviors. CONCLUSIONS: These findings suggest that the PAID, a brief, easy-to-administer instrument, may be valuable in assessing psychosocial adjustment to diabetes. In addition to high internal reliability, the consistent pattern of correlational findings indicates that the PAID is tapping into relevant aspects of emotional distress and that its particular feature, the measurement of diabetes-related emotional distress, is uniquely associated with diabetes-relevant outcomes. These data are also consistent with the hypothesis that diabetes-related emotional distress, separate from general emotional distress, is an independent and major contributor to poor adherence. Given that the study was limited to female patients using insulin, further examination of the clinical usefulness of the PAID will need to focus on more heterogeneous samples.

Adult↗
PubMed1994

Nitric oxide and the cardiovascular system.

Nitric oxide is a simple diatomic molecule that functions as a cellular messenger in a number of organ systems, included among which is the cardiovascular system. Serving several physiologic roles in the cardiovascular system, nitric oxide is an important determinant of basal vascular tone, regulates myocardial contractility, and modulates platelet-vessel wall interactions. From the perspective of cardiovascular pathophysiology, nitric oxide has been implicated in the pathogenesis of essential hypertension, atherosclerosis, and the hypotension associated with shock states. This review will focus in detail on the chemistry, biology, and pathobiology of nitric oxide as it relates to cardiovascular function.

Cardiovascular Diseases↗
PubMed1993

The BULIT-R: its reliability and clinical validity as a screening tool for DSM-III-R bulimia nervosa in a female tertiary education population.

The Bulimia Test (BULIT) has been updated to accommodate the DSM-III-R criteria for bulimia nervosa. Therefore, in this study, we evaluated the psychometric properties of the BULIT-R using a sample of young women at a tertiary educational institute. The results showed all 28 BULIT-R items correlated highly with the total test score (average = .59) and the internal reliability was high (.92). In terms of its concurrent validity, the BULIT-R correlated highly (.90) with the Bulimia Investigatory Test Edinburgh (BITE), a screening measure argued to detect bulimia nervosa. In terms of criterion-related validity, the optimal cutoff for the BULIT-R as a screening measure was 98 with this sample, using a semistructured DIS-III R interview administered by experienced clinicians who specialize in eating disorders. At this cutoff, the sensitivity was 100%, the specificity 99.0%, the negative predictive value 100%, and the positive predictive value 71.3%.

Adult↗
PubMed1992

The evaluation of a behavioural food and weight control programme for obese patients with noninsulin dependent diabetes.

We report here on the evaluation of a behaviour modification programme for food and weight control in noninsulin dependent diabetes mellitus (NIDDM). The results of this pilot study, involving a highly selected group of patients, showed that weight was reduced by an average of 4.5% over 11 weeks and that this difference was statistically significant. This average weight loss is in the range typically found for similar programmes. Glycosylated haemoglobin fell by 7.8% on average and serum total cholesterol fell by 3%, both statistically significant changes. Triglycerides fell by 17%, although this was not significant. The programme in its present form appears helpful in aiding motivated patients to make modest improvements in their blood sugars and lipids. However, we have identified a number of modifications and additions that could be made to improve it.

Adult↗
PubMed1992

Styles of psychological adjustment in diabetes: a focus on key psychometric issues and the ATT39.

While knowledge of the biomedical factors in diabetes has grown in a steady and systematic fashion over the past 60 years, attempts to define, measure, and understand the relevant psychological constructs have only begun recently. In particular, there is need for psychometrically sound tests to tap these dimensions. This study examined the psychometric characteristics of the ATT39, a promising measure of psychological adjustment to diabetes. The results, based on three patient samples and using the FACTOREP factor-matching procedure, suggested that the ATT39 has a large single factor only. This new subscale appears clinically to measure the integration of diabetes and its treatment into the lifestyle and personality of a patient with diabetes.

Adaptation, Psychological↗
PubMed1990

Is the prevalence of bulimia nervosa higher among tertiary education populations?

In this study the prevalence of bulimia nervosa was estimated among 243 women in a tertiary educational setting. The results showed 43.6% (95% CI, 37.4 to 49.8) to report binge eating, the cardinal feature of bulimia nervosa, at some stage in the past and 2.5% (95% CI, 1.0 to 5.6) the full criteria for current bulimia nervosa. These figures are significantly higher than those reported recently for a general population sample in the same age range. Despite methodological differences between the two surveys the results give some support to claims that women in these settings are at a greater risk of developing eating disorders.

Adult↗
PubMed1990

Adverse learning strategy: the Adelaide Diagnostic Learning Inventory and its subscale replicability in a medical student population.

The Adelaide Diagnostic Learning Inventory (ADLIMS) is a measure of learning styles and learning pathologies that was designed to investigate the impact of traditional approaches to learning versus problem-based learning and to identify students whose approach to learning tasks predicted poor academic performance. In this study, some important psychometric properties of the ADLIMS were examined, including its factor structure. In this study, factor replicability across samples was argued to provide a more robust and psychologically meaningful factor solution than that which can be obtained using traditional mathematical criteria. The results of the factor analysis did not confirm the presence of the four factor solution earlier reported for the ADLIMS, but did identify three clear factors that had very high replicability. An inspection of the items comprising these three factors showed that factor 1 tapped subjective distress related to poor study habits, lack of motivation to study, and distraction from social activities. Factor 2 tapped distress arising from high achievement expectations that were hampered by superficial or disorganized study habits that did not enable the student to grasp the relationships between concepts and ideas. Factor 3 tapped positive feelings and a sense of satisfaction associated with a problem-based approach to the learning of new study material. Although the internal reliability of the ADLIMS subscales met the requirements of a measure to be used in general research such as in the investigation of correlates among groups of medical students, they did not meet the higher requirements of a measure to be used to identify or predict individuals with pathological learning styles.

Humans↗
PubMed1990

'Normal but dead': perinatal mortality in non-malformed babies of birthweight 2.5 kg and over in the northern region in 1983.

The case notes relating to 75 of the 91 perinatal deaths of nonmalformed babies of birthweight greater than or equal to 2.5 kg born in the Northern Region in 1983 were examined. The major groups involved antepartum deaths of unknown cause (40%), and deaths due to intrapartum anoxia or trauma (35%). A case-control study compared each of the 75 cases with two controls matched for place of birth, obtained by taking the next two babies born in the same maternity unit (excluding perinatal deaths, birthweight less than 2.5 kg, and malformations). Four factors were found to be significantly associated with risk of perinatal death in this group: primigravidity, parity greater than or equal to 3, not booked for antenatal care by 20 weeks, and corrected birthweight less than 3.2 kg (adjusted for gestation). Two further factors were related only to the risk of perinatal death consequent upon intrapartum events: labour post-term and malpresentation in labour. All four factors relevant to the whole group remained independently associated with risk of perinatal death after multivariate analysis by two techniques. Adjusted odds ratios (95% CI) were estimated as: primigravidity 2.1 (1.1 to 4.1); parity three or more 5.7 (1.9 to 17); not booked for antenatal care by 20 weeks 15.7 (3.0 to 81); and corrected birthweight less than 3.25 kg 2.5 (1.3 to 4.6). An avoidable factor, as defined, was detected in 50% of deaths. In 30% of deaths there was an avoidable factor (grade 2) such that absence may have been expected to lead to a different outcome had all other factors remained equal. Of the avoidable factors detected, 61% related to intrapartum management, as did 76% of the grade 2 factors. Most of these involved failure to respond to evidence of fetal distress in labour. The defined group constituted 21% of all perinatal deaths, suggesting that this is an important category, particularly as their potential for normal survival should otherwise have been high.

Birth Weight↗
PubMed1990

Australasian field trials of the Mental and Behavioural Disorders section of the draft ICD-10.

Field trials of the "Mental and Behavioural Disorders" section of the 1987 draft of the ICD-10 have been co-ordinated for the World Health Organisation by a number of regional centres. The design of the field trials and the major features of ICD-10 are briefly discussed. The results of the field trial in the Western Pacific region are described, and compared with the results of the original DSM-III field trials. ICD-10 appears to be an acceptably reliable diagnostic system, and the ratings of its feasibility and utility by participating clinicians suggest that it will be seen as a distinct advance over ICD-9.

Australia↗