Biomedical subjects

David Cox

Publications and source records attributed to David Cox.

23 records · Page 2Linked to original sources

PubMed2003

Effects of prior beta-blocker therapy on clinical outcomes after primary coronary angioplasty for acute myocardial infarction.

We hypothesized that pretreatment with beta blockers may improve clinical outcomes after primary angioplasty for acute myocardial infarction. We pooled clinical, angiographic, and outcomes data on 2,537 patients enrolled in the Primary Angioplasty in Myocardial Infarction (PAMI), PAMI-2, and Stent PAMI trials. We classified patients into a beta group (n = 1,132) if they received beta-blocker therapy before primary angioplasty or a no-beta group (n = 1,405) if they did not. We evaluated procedural complications and in-hospital and 1-year outcomes (death and major adverse cardiac events [death, reinfarction, target vessel revascularization, or stroke]) between groups. Beta patients were younger, had higher systolic blood pressure and heart rate, and were more likely to be in Killip class I at admission. They had lower left ventricular ejection fraction, greater door-to-balloon time, greater likelihood of having a left anterior descending artery culprit lesion, but a similar incidence of Thrombolysis In Myocardial Infarction 3 flow after angioplasty (92.6% vs 92.7%, p = 0.91). The beta group had less procedural complications (23% vs 34%, p <0.0001) and a lower incidence of death (1.8% vs 3.7%, p = 0.0035) and major adverse cardiac events (5.5% vs 7.8%, p = 0.027) during hospitalization. At 1 year, mortality remained lower in beta patients (4.9% vs 6.7%, log-rank p = 0.055). After adjustment for baseline differences, beta patients had significantly lower in-hospital mortality (odds ratio 0.41; 95% confidence interval 0.20 to 0.84; p <0.0148) and nonsignificantly lower 1-year mortality (odds ratio 0.72; 95% confidence interval 0.47 to 1.08; p = 0.11). Thus, pretreatment with beta blockers has an independent beneficial effect on short-term clinical outcomes in patients undergoing primary angioplasty for acute myocardial infarction.

Adrenergic beta-Antagonists↗

PubMed2003

Analysis of a key regulatory region upstream of the Myf5 gene reveals multiple phases of myogenesis, orchestrated at each site by a combination of elements dispersed throughout the locus.

Myf5 is the first myogenic regulatory factor to be expressed in the mouse embryo and it determines the entry of cells into the skeletal muscle programme. A region situated between -58 kb and -48 kb from the gene directs Myf5 transcription at sites where muscles will form. We now show that this region consists of a number of distinct regulatory elements that specifically target sites of myogenesis in the somite, limbs and hypoglossal cord, and also sites of Myf5 transcription in the central nervous system. Deletion of these sequences in the context of the locus shows that elements within the region are essential, and also reveals the combinatorial complexity of the transcriptional regulation of Myf5. Both within the -58 kb to -48 kb region and elsewhere in the locus, multiple sequences are present that direct transcription in subdomains of a single site during development, thus revealing distinct phases of myogenesis when subpopulations of progenitor cells enter the programme of skeletal muscle differentiation.

Animals↗

PubMed2002

Comparison of effectiveness of primary angioplasty for proximal versus distal right coronary artery culprit lesion during acute myocardial infarction.

From the cohort of 4,023 patients enrolled in the Primary Angioplasty for Myocardial Infarction (PAMI) trials, we pooled clinical, angiographic, and outcomes data on 1,521 patients with culprit lesions in the right coronary artery (RCA). We compared angiographic results, procedural complications, and in-hospital and 1-year clinical outcomes between patients with proximal RCA (n = 572) versus nonproximal RCA culprit lesions (n = 949). Patients with proximal RCA culprit lesions were older, had lower systolic blood pressure, greater diameter stenosis, and were less likely to have Thrombolysis In Myocardial Infarction (TIMI) 2 or 3 flow (19% vs 31%; p <0.0001) before percutaneous coronary intervention (PCI). After PCI, the incidence of TIMI 3 flow (94% vs 93%) was similar between groups. Patients with proximal RCA lesions were more likely to have bradyarrhythmias (30% vs 23%, p = 0.016) and require an intra-aortic balloon pump (IABP; 4.6% vs 2%, p = 0.034) during PCI. In-hospital complications, including mortality (2.3% vs 2.2%) and reinfarction (1.4% vs 1.1%), and the 1-year incidence of death, reinfarction, ischemia driven target vessel revascularization, and major adverse cardiovascular events were similar between groups. After adjustment for baseline differences, proximal RCA location of the culprit lesion was independently associated with greater IABP use (odds ratio 2.41, 95% confidence interval 1.04 to 5.58) but not with bradyarrhythmias during PCI. Thus, in patients with acute myocardial infarction referred for primary angioplasty, proximal RCA location of the culprit lesion is associated with excellent clinical outcomes that are similar to nonproximal RCA lesions.

Aged↗

PubMed2002

A cross-sectional study of the prevalence of psychopathology in adults with congenital heart disease.

OBJECTIVE: Several studies have suggested high levels of psychopathology in children and adolescents with congenital heart disease (CHD). However, little information is published relating to psychopathology in adults with CHD. We wanted to estimate the prevalence of psychopathology in adults with CHD. DESIGN: A cross-sectional study of attenders at an adult CHD clinic compared with orthopaedic outpatients of the same hospital. SETTING: A tertiary CHD clinic in South Wales, the comparison group being recruited from the orthopaedic outpatient clinic in the same teaching hospital. PARTICIPANTS: One hundred and one individuals attending the CHD clinic were identified, 87 successfully completed questionnaires. Forty-five from 80 randomly selected orthopaedic outpatients completed questionnaires. MAIN OUTCOME MEASURES: The General Health Questionnaire 30 (GHQ30) and the Hospital Anxiety and Depression Scale (HADS). RESULTS: We found a statistically significant difference in the mean GHQ 30 score between the CHD and comparison groups, the CHD group having lower scores. The difference remained after adjustment for age and sex. The mean HADS scores differed in the same direction, and were of borderline statistical significance. CONCLUSIONS: In this study, adult subjects with CHD had a lower prevalence of psychopathology. Possible explanations for this finding are discussed.

Adaptation, Psychological↗

PubMed2002

Clustering and heritability of insulin resistance in Chinese and Japanese hypertensive families: a Stanford-Asian Pacific Program in Hypertension and Insulin Resistance sibling study.

The clustering between hypertension and other metabolic abnormalities related to insulin resistance syndrome (IRS) has been investigated in cross-sectional and prospective studies. Offspring studies have revealed that the clustering characteristics of IRS have familial components. However, it is not known whether the clustering also occurs in siblings (sibs) with different levels of blood pressure (BP). In addition, the genetic susceptibility accounting for the clustering in hypertensive families has not been determined. Siblings with Japanese or Chinese ancestry and having either similar BP levels (concordant sibs) or different BP levels (discordant sibs) were recruited. The delta method and variance component model were applied to analyze the differences in metabolic variables between hypertension (HTN) and low BP (LBP) sibs, and to compute the polygenic heritabilities for these metabolic variables and insulin sensitivity. After adjustment for age, gender and body mass index (BMI), HTN (n=393) sibs had higher levels of triglyceride (p < 0.0001), VLDL-cholesterol (p<0.0001), fasting insulin (p < 0.05), and homeostasis model assessment of insulin resistance (HOMAir) (p < 0.05) than LBP sibs (n = 389), but there were no differences in fasting glucose or high density lipoprotein (HDL)-cholesterol. The HTN sibs also had higher plasma glucose and insulin levels at 2 h after 75 g oral glucose loading (p<0.001 and p<0.01, respectively). The heritability estimates for fasting glucose, fasting insulin and HOMAir were 0.58, 0.43 and 0.46, respectively; for triglyceride, HDL-cholesterol, and BMI they were 0.60, 0.63 and 0.54, respectively. In hypertensive families, sibs with extreme levels of BP have significant differences in IRS-associated metabolic variables. The clustering characteristics and the significance of heritability estimation for these metabolic variables indicate that IRS is familial in nature and heritable in Chinese and Japanese hypertensive families.

Adult↗