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D J Catellier

Publications and source records attributed to D J Catellier.

6 recordsLinked to original sources
PubMed2001

A prospective study of coronary heart disease and the hemochromatosis gene (HFE) C282Y mutation: the Atherosclerosis Risk in Communities (ARIC) study.

Increased iron stores may play a role in the development of coronary heart disease (CHD) by increasing lipoprotein oxidation. Recently, mutations have been discovered in the gene (HFE) for hereditary hemochromatosis, an autosomal recessive condition of disordered iron metabolism, absorption, and storage. It is possible that people who carry HFE mutations have increased risk of CHD. We used a prospective case-cohort design (243 CHD cases and 535 non-cases) to determine whether the HFE C282Y mutation was associated with incident CHD in a population-based sample of middle-aged men and women. The frequencies of homozygosity and heterozygosity for the C282Y mutation in the ARIC study population were 0.2% (one homozygous person) and 6%, respectively. The C282Y mutation was associated with nonsignificantly increased risk of CHD (relative risk=1.60, 95% CI 0.9-2.9). After adjusting for other confounding risk factors (age, race, gender, ARIC community, smoking status, diabetes status, hypertension status, LDL cholesterol, HDL cholesterol, and triglycerides), the association became stronger (relative risk=2.70, 95% CI 1.2-6.1). However, a sensitivity analysis showed that this estimate of relative risk was somewhat unstable due to few subjects in some strata. Our prospective findings suggest that individuals carrying the HFE C282Y mutation may be at increased risk of CHD.

Cohort Studies↗
PubMed2000

Tests for gaussian repeated measures with missing data in small samples.

For small samples of Gaussian repeated measures with missing data, Barton and Cramer recommended using the EM algorithm for estimation and reducing the degrees of freedom for an analogue of Rao's F approximation to Wilks' test. Computer simulations led to the conclusion that the modified test was slightly conservative for total sample size of N=40. Here we consider additional methods and smaller sample sizes, Nin¿12,24¿. We describe analogues of the Pillai-Bartlett trace, Hotelling-Lawley trace and Geisser-Greenhouse corrected univariate tests which allow for missing data. Eleven sample size adjustments were examined which replace N by some function of the numbers of non-missing pairs of responses in computing error degrees of freedom. Overall, simulation results allowed concluding that an adjusted test can always control test size at or below the nominal rate, even with as few as 12 observations and up to 10 per cent missing data. The choice of method varies with the test statistic. Replacing N by the mean number of non-missing responses per variable works best for the Geisser-Greenhouse test. The Pillai-Bartlett test requires the stronger adjustment of replacing N by the harmonic mean number of non-missing pairs of responses. For Wilks' and Hotelling-Lawley, an even more aggressive adjustment based on the minimum number of non-missing pairs must be used.

Choline↗
PubMedDate not supplied

Changes in acute myocardial infarction risk and patterns of practice for patients older and younger than 70 years, 1987-90.

OBJECTIVE: To evaluate temporal changes in risk and patterns of hospital practice for acute myocardial infarction (AMI). DESIGN/PATIENTS: Retrospective analysis of age-related medical therapy and outcome of 342 consecutive patients (132 at least 70 years old and 210 younger than 70) with AMI between July 1, 1989, and June 30, 1990, and comparison with data from two previous analyses of AMI practice in 1987 (n = 207) and 1988-89 (n = 402). SETTING: Tertiary care medical centre. INTERVENTIONS: No direct interventions; results of the two previous AMI practice pattern analyses, however, were propagated during the practice time of the most recent analysis. RESULTS: In 1989-90, hospital mortality was higher (19%) among patients at least 70 years old compared with patients younger than 70 (8%) (P less than 0.01). Therapies proven by repeated clinical trials to be effective in reducing AMI risk were all used less frequently in patients aged at least 70 years: thrombolysis (20 versus 43%); beta-blockers (41 versus 62%); acetylsalicylic acid (71 versus 87%); and nitrates (86 versus 97%). Qualitatively, these age-specific patterns of AMI mortality and therapy were similar to previous studies. Quantitatively, however, comparing 1987 with 1989-90 demonstrated parallel and marked increases in the use of all proven medications in both age groups, ranging from 42 to 230% (P less than 0.01). There was also a significant overall decrease in mortality from the 1987 patient cohort (20%) to the 1989-90 cohort (13%) (P less than 0.05). The decrease in mortality was entirely due to decreased mortality within the group 70 years or older; 35% in 1987 versus 19% in 1989-90 (P less than 0.05). Mortality in the AMI patients younger than 70 years old remained unchanged from 1987 to 1989-90. CONCLUSIONS: Pattern of practice analyses were associated with, and may have contributed to, improved patient care and outcomes in AMI. Increased use of effective AMI medical therapy had a greater benefit in elderly higher risk AMI patients than lower risk younger patients. Persisting age-specific differences in AMI therapy may respond to more direct quality improvement measures, such as critical path management.

Adrenergic beta-Antagonists↗