[Cardiovascular prevention and coronary heart disease mortality decrease].

In many ways, adjustment for publication bias in meta-analysis parallels adjustment for ascertainment bias in genetic studies. We investigate a previously published simulation-based method for dealing with complex ascertainment bias and show that it can be modified for use in meta-analysis when publication bias is suspected. The method involves simulating sets of pseudo-data under the assumed model using guesses for the unknown parameters. The pseudo-data are subjected to the same selection criteria as are believed to have operated on the original data. A conditional likelihood is then used to estimate the adjusted values of the unknown parameters. This method is used to re-analyse a published meta-analysis of the effect of the MTHFR gene on homocysteine levels. Simulation studies show that the pseudo-data method is unbiased; they give an indication of the number of pseudo-data values required and suggest that a two-stage adjustment produces less variable estimates. This method can be thought of as an example of the selection model approach to publication bias correction. As the selection mechanism must be assumed, it is important to investigate the sensitivity of any conclusions to this assumption.

Cardiovascular Diseases↗

PubMed2006

Diabetes and the metabolic syndrome--when is it best to intervene to prevent?

In addition to microvascular complications, patients with type 2 diabetes are at increased risk of cardiovascular disease (CVD) and mortality. An important initial step in reducing the overall burden of CVD, as well as other diabetes complications, is to prevent progression to diabetes in individuals at risk. A number of studies have indicated the increased presence of both established and emerging cardiovascular risk factors associated with the metabolic syndrome in individuals before the onset of diabetes. First-line therapy in the treatment of the metabolic syndrome risk factors is lifestyle intervention, which can be highly successful in preventing or delaying progression to overt diabetes, but on its own may not achieve and/or maintain adequate risk reduction. In this case, individuals need to be identified and treated with appropriate pharmacological interventions. The data are unequivocal in the importance of the timely identification of at-risk subjects, and implementation of effective treatment strategies, which could potentially reduce diabetes- and CVD-related morbidity and mortality.

Cardiovascular Diseases↗

PubMed2006

Use, intentions, and beliefs about hormone replacement therapy in women with and without diabetes.

OBJECTIVES: (1) Describe women's (a) hormone replacement therapy (HRT) use patterns, (b) intentions to use or continue to use HRT among women in the early and late stages of menopause, and (c) beliefs about using HRT and (2) compare these beliefs, patterns, and intentions between women with and without diabetes 10-12 months after news from the women's health initiative was widely publicized. METHODS: A survey mailed to female enrollees of a not-for-profit managed care organization (MCO) between 46 and 60 years of age and with or without diabetes. Descriptive statistics were calculated. Chi-square analysis was used to determine significant differences between four different HRT use and menopause stage groups, (1) early stage never user, (2) late stage never user, (3) late stage current user, and (4) late stage previous user. Analysis of variance (ANOVA) was used to identify significant belief differences between the four groups. Repeated-measures ANOVA was performed to examine differences between women with and without diabetes. RESULTS: Most women did not intend to initiate HRT. About 86% of current HRT users intended to continue. Never users with diabetes were significantly more uncertain about HRT intention than non-diabetic women. All beliefs were significantly different (p<0.001) between the four groups, but not between women with and without diabetes. CONCLUSION: Women in different groups hold different beliefs about HRT use. Uncertainty among women with diabetes is not resolved as quickly as among women without diabetes.

Cardiovascular Diseases↗