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Steven J Bowlin

Publications and source records attributed to Steven J Bowlin.

9 recordsLinked to original sources

The independent correlation between high-density lipoprotein cholesterol and subsequent major adverse coronary events.

BACKGROUND: There is substantial evidence from clinical trials that lowering low-density lipoprotein cholesterol (LDL-C) reduces cardiovascular risk. There is less evidence for the salutatory effects of raising high-density lipoprotein cholesterol (HDL-C). The predictive strength of an initial HDL-C measurement and its change over time for major adverse coronary events is not well understood. METHODS: We identified a cohort of all 6928 patients in an urban primary care practice who had two or more lipid measurements between January 1985 and December 1997. We used bivariable and multivariable (Cox proportional hazards) techniques to identify independent predictors of subsequent major adverse coronary events (hospitalization for myocardial infarction or acute coronary syndrome) after the second set of lipid measurements. RESULTS: The time between first and second lipid measurements averaged 2.6 years. During a mean of 5.1 +/- 3.2 years of observation after their second lipid measurements, 2167 (31%) patients had an acute coronary event. Patients having events were significantly older, more often white, male, and smokers and more often had antecedent diabetes, hypertension, coronary heart disease, and myocardial infarctions. Adjusting for covariates, a 10-mg/dL higher initial HDL-C was associated with an 11% (95% CI 7%-14%) lower risk of coronary events. A 10-mg/dL increase in HDL-C between lipid measurements was associated with a 7% (95% CI 3%-10%) lower risk of events. Neither initial or change in triglycerides nor LDL-C predicted subsequent coronary events. CONCLUSION: High-density lipoprotein cholesterol measurements and change in HDL-C predicted major adverse coronary events in this urban practice, which provides support studying interventions targeting HDL-C for cardiovascular risk reduction.

Adult↗

The association between fibrate use, change in high-density lipoprotein cholesterol, and the risk of cardiovascular disease: a retrospective chart review involving up to 8 years of follow-up.

BACKGROUND: Clinical trials have indicated that the use of fibric acid derivatives confers a benefit against cardiovascular disease (CVD) in selected populations. However, whether fibrates provide a CVD risk reduction independent of changes in the traditional lipoprotein fractions and other known CVD risk factors is not clear. OBJECTIVE: This study examined whether the use of fibrate therapy in a general clinical setting provided cardiovascular benefits independent of changes in the traditional lipoprotein fractions. METHODS: This was a matched, retrospective cohort study. From the electronic records of a large health maintenance organization in the northwestern United States, we identified a population that had newly initiated fibrate pharmacotherapy between January 1, 1996, and December 31, 2000. We then identified a comparator group of patients not using fibrates, matching them to fibrate users based on high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) levels, age, sex, and year of HDL-C and TG measurement. Subjects were followed until a CVD hospitalization, termination from the health plan, or December 31, 2003, whichever came first. We then used multivariate analysis accounting for differences in followup to identify predictors of CVD incidence. RESULTS: The study population included 1722 matched pairs (56.6% male; mean [SD] age, 57.3 [11.1] years). The patients who had newly initiated fibrate pharmacotherapy had low baseline HDL-C levels (mean, 37.4 mg/dL) and very high TG levels (617 mg/dL). The 2 groups were similar overall, with the only significant differences between fibrate users and nonfibrate controls being a greater prevalence of diabetes (37.7% vs 34.3%, respectively; P=0.040) and greater use of angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (56.6% vs 51.6%, respectively; P=0.003), beta-blockers (53.7% vs 49.0%; P=0.006), calcium channel blockers (25.1% vs 20.9%; P=0.004), and niacin (11.7% vs 7.4%; P<0.001). Overall, CVD risk was 26% lower for every 5-mg/dL increment in HDL-C. After adjustment for age, sex, smoking history, diabetes, existing diagnosis of CVD, weight, systolic blood pressure, baseline HDL-C, change in HDL-C, total cholesterol, TG, and use of statins, niacin, and other CVD drugs, fibrate use did not confer an additional CVD risk reduction. CONCLUSIONS: In this cohort with low baseline HDL-C levels and very high TG levels, fibrate use did not confer an independent CVD risk reduction after adjustment for CVD risk factors. Given the current obesity epidemic in the United States and the corresponding rise in the number of patients with the metabolic syndrome, the apparent risk reduction observed in association with higher HDL-C levels should not be ignored.

Age Factors↗

Antidiabetic therapy and the risk of heart failure in type 2 diabetic patients: an independent effect or confounding by indication.

PURPOSE: This study assesses the effect of the type of antidiabetic treatment on the risk of developing congestive heart failure (CHF) in type 2 diabetes. METHODS: The study was derived from the U.K.-based General Practice Research Database (GPRD) comprised of 3.5 million subjects followed between 1987 and 2001. A total of 21 888 type 2 diabetic patients were identified. A 6:1 matched nested case-control design was employed. Conditional logistic regression was used to derive adjusted odds ratios (ORs) for the association of drug treatment with CHF controlling for diabetes duration and for diseases known to affect the risk of CHF. Antidiabetic drug exposure was defined as the receipt of at least one prescription for an antidiabetic medication within the 3 months prior to the date of CHF diagnosis. RESULTS: There were 1301 incident cases of CHF in the cohort, matched to 7788 controls. After risk factor adjustment, there was a 1.2-fold increase in the risk of CHF for sulphonylureas (SUs) (OR = 1.17; 95%CI = 1.00-1.37) and metformin monotherapies (OR = 1.22; 95%CI = 0.97-1.52), a 1.6-fold increase with combinations of metformin and SUs (OR = 1.62; 95%CI = 1.30-2.02), a 2.2-fold increase with oral tricombinations (OR = 2.16; 95%CI = 0.96-4.86) and a 1.5-fold increase for insulin compared to no exposure (OR = 1.52; 95%CI = 1.06-2.17). Compared to SUs, bicombinations of metformin and SUs showed a statistically significant 1.4-fold increase in the odds of CHF (OR = 1.38; 95%CI = 1.13-1.69). CONCLUSIONS: All antidiabetic medications were associated with an increased likelihood of CHF compared to no antidiabetic exposure. The risk of CHF increased with the complexity of the antidiabetic regimen suggesting that it is the diabetes severity, which imparts risk and not necessarily the antidiabetic regimen itself.

Adult↗

Glycemic control from 1988 to 2000 among U.S. adults diagnosed with type 2 diabetes: a preliminary report.

OBJECTIVE: To describe the changes in demographics, antidiabetic treatment, and glycemic control among the prevalent U.S. adult diagnosed type 2 diabetes population between the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and the initial release of NHANES 1999-2000. RESEARCH DESIGN AND METHODS: The study population was derived from NHANES III (n = 1,215) and NHANES 1999-2000 (n = 372) subjects who reported a diagnosis of type 2 diabetes with available data on diabetes medication and HbA(1c). Four therapeutic regimens were defined: diet only, insulin only, oral antidiabetic drugs (OADs) only, or OADs plus insulin. Multiple logistic regression was used to examine changes in antidiabetic regimens and glycemic control rates over time, adjusted for demographic and clinical risk factors. The outcome measure for glycemic control was HbA(1c). Glycemic control rates were defined as the proportion of type 2 diabetic patients with HbA(1c) level <7%. RESULTS: Dietary treatment in individuals with diabetes decreased as the sole therapy from 27.4 to 20.2% between the surveys. Insulin use also decreased from 24.2 to 16.4%, while those on OADs only increased from 45.4 to 52.5%. Combination of OADs and insulin increased from 3.1 to 11.0%. Glycemic control rates declined from 44.5% in NHANES III (1988-1994) to 35.8% in NHANES 1999-2000. CONCLUSIONS: Treatment regimens among U.S. adults diagnosed with type 2 diabetes have changed substantially over the past 10 years. However, a decrease in glycemic control rates was also observed during this time period. This trend may contribute to increased rates of macrovascular and microvascular diabetic complications, which may impact health care costs. Our data support the public health message of implementation of early, aggressive management of diabetes.

Administration, Oral↗

Silicone gel breast implant rupture rates: research issues.

Documenting the rate of rupture of silicone breast implants appears to be deceptively easy. Largely because of the phenomenon of "silent rupture," it isn't. The authors explore the various technical biases (selection, misclassification, and confounding) and methodological problems that have plagued much of the research conducted to date. By means of a series of illustrations, they argue that explantation has limited utility. Noninvasive techniques have to be used to gather the proper type of data on the timing and frequency of these events. Only with the proper incidence data will researchers be able to identify better the different mechanisms underlying implant rupture and the relative importance of each. The authors recommend that better and standardized definitions of implant rupture be developed, that greater recognition be given to the technical biases and a greater effort be made to eliminate them from investigations of implant rupture, and that more research be conducted by multidisciplinary teams. Because of the growing awareness of the complexity of this issue, the authors also recommend that properly constituted advisory teams be used to provide comprehensive oversight of future research projects from beginning to end.

Bias↗