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Biomedical subjects

B C Martin

Publications and source records attributed to B C Martin.

At least 37 records · Page 2Linked to original sources

Alcohol intake and risk of breast cancer: the euramic study.

To evaluate the association of alcohol intake with the risk of breast cancer in post-menopausal women, we analyzed the data from an international case-control study conducted in five European countries (FRG, Switzerland, Northern Ireland, the Netherlands and Spain). Information on alcohol intake was available in 315 cases and 364 controls. Medians for the tertiles of alcohol intake among current drinkers were 1.7, 6.0, and 20.0 g/day. Adjusted relative risks (and 95% confidence intervals) of breast cancer for each tertile of intake in current drinkers, compared to never drinkers, were 1.00 (0.60-1.67), 1.01 (0.60-1.73), and 1.18 (0.69-2.03). The adjusted relative risk for ex-drinkers was 1.73 (1.07-2.79). Among both current drinkers and ex-drinkers, the relative risk was higher for those with body mass index above the median compared to those with body mass index below the median. These results do not support a dose-response effect of alcohol on breast cancer risk, although consumption levels were too low to exclude increased risk with high regular intake. Further research is necessary to evaluate the risk of developing breast cancer among ex-drinkers and the potential interaction between body mass index and alcohol drinking.

Alcohol Drinking↗

Health care triage alternatives and the influence of health insurance, education and race.

The relationship between one of Andersen's enabling factors, health insurance status and the choice of a pharmacist as the initial contact in the health care system was examined via telephone surveys. Eighty-seven percent of the sample reported having some form of health insurance. Of all intended health care provider contacts, pharmacists were selected as the initial contact 21% of the time. Logistic regression identified insurance status, education and race as significant (alpha < 0.05) covariates in the model. The odds ratios generated from the logit model indicated that non-whites, persons with less education and no health insurance were more likely to select a pharmacist for triage. The study concluded that uninsured persons were nearly twice as likely to seek pharmacist triage than insured individuals. Pharmacists may be filling an important triage gap for individuals who have limited financial access to traditional sources of physician care.

Adolescent↗

The impact of implementing a more restrictive prescription limit on Medicaid recipients. Effects on cost, therapy, and out-of-pocket expenditures.

On November 1, 1991, the Georgia Department of Medical Assistance reduced the maximum number of monthly reimbursable prescriptions from six to five. This policy change provided a natural experiment to investigate the recipient responses to a decrease in an existing prescription limit. The research design was a quasiexperimental, retrospective, 12-month interrupted time-series analysis of a cohort. The cohort consisted of 743 ambulatory recipients who were high prescription users. Complete Medicaid claims data were obtained, in addition to pharmacy-generated computer profiles for all cohort recipients to determine Medicaid and out-of-pocket prescriptions expenditures. Interrupted time-series analyses were performed to model the effect of the five-prescription limit on total, Medicaid-reimbursed, out-of-pocket, and prescription use across eight therapeutic categories. After the implementation of the five-prescription limit, total prescription use fell 6.6%, prescriptions reimbursed by Medicaid fell 9.9%, and prescriptions paid for out-of-pocket increased 9.7%. Abrupt, permanent decreases were observed for cardiovascular, miscellaneous, pulmonary, and palliative therapeutic drug categories (alpha = 0.05), whereas gastrointestinal, chemotherapy, hormone (insulin), and central nervous system prescription use remained constant. The implementation of a more restrictive prescription limit alters prescription regimens potentially predisposing elderly Medicaid recipients to clinical consequences. Further examination of the health outcomes of these recipients is necessary.

Adult↗

Tissue antioxidants and postmenopausal breast cancer: the European Community Multicentre Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast (EURAMIC).

Antioxidants may protect against free radical mediated carcinogenesis. Epidemiological studies have not confirmed this hypothesis for breast cancer, possibly because of methodological limitations. Time-integrated exposure of alpha-tocopherol and beta-carotene in adipose tissue, and selenium in toenails was investigated in a case-control study among postmenopausal women, ages 50-74 years, from five European countries. The study group comprised 347 incident breast cancer cases and 374 controls. Mean antioxidant levels, adjusted for age and center, did not significantly differ for alpha-tocopherol (cases were 4.5% higher than controls), beta-carotene (3.0% lower), or selenium (1.8% lower). Odds ratios for highest versus lowest tertiles of exposure, adjusted for potential confounders, were 1.15 (95% confidence interval, 0.75-1.77), 0.74 (0.45-1.23), and 0.96 (0.63-1.47), respectively, without evidence for a decreasing trend. No statistically significant interactions were observed. Moreover, a provisional antioxidant score, indicating whether concentrations were above the median for zero, one, two, or all three antioxidants, yielded odds ratios of 1.00 (reference; all below median), 1.58, 1.58, and 1.21, respectively (chi2 for association = 4.00; P = 0.26). These results do not support the hypothesis that antioxidants are important determinants of this hormone-related malignancy among postmenopausal women.

Adipose Tissue↗

Natural history of impaired glucose tolerance: follow-up at Joslin Clinic.

The goal of this study was to examine follow-up data on the offspring of two parents with NIDDM who have IGT to identify predictors of progression to NIDDM. The study group consisted of 80 individuals with IGT (WHO criteria), 28 of whom had IGT at baseline, and 52 who developed it during follow-up. Both an oral glucose tolerance test (OGTT) and an intravenous glucose tolerance test (IVGTT) were performed at baseline. After a median follow-up interval of 8 years, 35% had progressed to NIDDM, 37% had reverted to normal glucose tolerance, and 29% still had IGT. Those who progressed were younger and more obese than non-progressors. Glucose and insulin values from the OGTT that established the diagnosis of IGT were analysed by multiple logistic regression to determine which time points best discriminated between progressors and non-progressors. High insulin, but not glucose, values at 0 and 120 min distinguished progressors from non-progressors. Values at other sample times that were significantly different (p < 0.05) in progressors were: higher glucose values at 30, 45, and 60 min and higher insulin values at 90 and 180 min. Multiple logistic regression analysis of Bergman's minimal model parameters obtained from the IVGTTs performed at baseline demonstrated that, once IGT is established, low acute phase insulin secretion as well as low insulin sensitivity are significant predictors of progression to NIDDM.

Adult↗

Adipose tissue isomeric trans fatty acids and risk of myocardial infarction in nine countries: the EURAMIC study.

Dietary isomeric trans fatty acids-mainly produced by hydrogenation of oils-are suspected of increasing the risk of coronary heart disease. Dietary trans fatty acid intake is reflected in the fatty acid composition of adipose tissue. In an international multicentre study in eight European countries and Israel (EURAMIC), adipose tissue aspiration samples were obtained from 671 men with acute myocardial infarction (AMI), aged 70 years or less, and 717 men without a history of AMI (controls). The proportion of fatty acids, including isomeric trans monoenoic fatty acids with 18 carbon atoms (C18:1), was determined by gas chromatography. Although there were considerable differences between countries in mean (SD) proportion of adipose tissue C18:1 trans fatty acids, there was no overall difference between cases (1.61 [0.92]%) and the controls (1.57 [0.86]%). The risk of AMI did not differ significantly from 1.0 over quartiles of adipose C18:1 trans fatty acids: the multivariate odds ratio was 0.97 (95% CI 0.56-1.67) for the highest versus lowest quartile. After exclusion of subjects from Spanish centres because they had far lower proportions of adipose trans fatty acids than subjects from other countries, there was a tendency to increased risk of AMI in the upper quartiles of C18:1 trans; however, the trend was not statistically significant. Our results reflect considerable differences between countries in dietary intake of trans fatty acids but do not suggest a major overall effect of C18:1 trans fatty acids on risk of AMI. We cannot exclude the possibility that trans fatty acids have a significant impact on risk of AMI in populations with high intake.

Adipose Tissue↗

Association between beta-carotene and acute myocardial infarction depends on polyunsaturated fatty acid status. The EURAMIC Study. European Study on Antioxidants, Myocardial Infarction, and Cancer of the Breast.

Because antioxidants may play a role in the prevention of coronary heart disease by inhibiting the peroxidation of polyunsaturated fatty acids (PUFAs), the combined association of diet-derived antioxidants and PUFAs with acute myocardial infarction (MI) was investigated. This multicenter case-control study included 674 patients and 725 control subjects in eight European countries and Israel. Fatty acid composition and alpha-tocopherol and beta-carotene levels were determined in adipose tissue; selenium level was determined in toenails. For alpha-tocopherol no association with MI was observed at any PUFA level. The overall multivariate odds ratio (OR) for low (10th percentile) versus high (90th percentile) beta-carotene was 1.98 (95% confidence interval [CI], 1.39 to 2.82). The strength of this inverse association with MI was dependent on PUFA levels (in tertiles): for low PUFA, the OR for low versus high beta-carotene was 1.79 (95% CI, 0.98 to 3.25), for medium PUFA the OR was 1.76 (95% CI, 1.00 to 3.11), and for high PUFA 3.47 (95% CI, 1.93 to 6.24). For selenium increased risk was observed only at the lowest PUFA tertile (OR, 2.49; 95% CI, 1.22 to 5.09). This interaction between selenium and PUFAs was not significant and may at least partly be explained by a higher proportion of smokers at the low PUFA level. These findings support the hypothesis that beta-carotene plays a role in the protection of PUFAs against oxidation and subsequently in the protection against MI. No evidence was found that alpha-tocopherol or selenium may protect against MI at any level of PUFA intake.

Adipose Tissue↗

Factors modifying the risk of IDDM in offspring of an IDDM parent.

Offspring of mothers with insulin-dependent diabetes mellitus (IDDM) have a much lower risk of IDDM than do offspring of diabetic fathers, and this risk is particularly low for offspring born to diabetic mothers over the age of 25 years. To determine whether increasing maternal age also protects the offspring of IDDM fathers from IDDM, we surveyed 367 IDDM fathers (IDDM onset before age 35) who first came to the Joslin Clinic (Boston, MA) between 1945 and 1969. Of the 840 offspring of these men, IDDM developed in 28 before the age of 20, giving a cumulative risk of 5.1 +/- 1.0% (means +/- SE). Because this is similar to the result of our earlier study of IDDM fathers, the two groups were combined to give 1,084 offspring, 39 having IDDM (cumulative risk of IDDM 5.4 +/- 0.9% by age 20), for comparison with our cohort of 1,391 offspring of 739 IDDM mothers. In that cohort, IDDM developed in 20 offspring before the age of 20 years, giving a cumulative risk of 2.1 +/- 0.5%. The risk of diabetes in offspring was higher if the parent's IDDM was diagnosed before age 11 than if it was diagnosed later: 9.3 compared with 4.0% (P = 0.006) for the offspring of IDDM fathers and 2.7 compared with 1.8% for the offspring of IDDM mothers (P = 0.06). In the families in which the father's IDDM was diagnosed after age 11, a protective effect of maternal age > or = 25, similar to that in families of IDDM mothers, seems to be present.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Spontaneous↗

Effect of drug interactions on outcomes of patients receiving warfarin or theophylline.

The effect of drug interactions on costs and other outcomes for hospitalized patients receiving warfarin or theophylline was studied. Data were collected from medical records during a one-year period in two community teaching hospitals in Maryland. The data included demographic information, the duration of study-drug therapy, the number of days spent in the intensive care unit, the length of stay (LOS) in the hospital, the number of prothrombin-time tests and serum theophylline assays, and the test results. A multiple-regression procedure was used to compare outcomes of patients who were prescribed specific drugs interacting with warfarin or theophylline with those of patients who were not. Among warfarin-treated patients, there was a significant difference in each outcome measure (LOS, number of laboratory tests, and test results) between those who received an interacting drug and those who did not; mean LOS was 3.14 days longer in patients given an interacting drug. No significant differences in outcome measures were observed between the two groups of theophylline-treated patients. The cost of the increased LOS attributed to the presence of a drug interacting with warfarin was estimated to range from $779 to $1005 per hospitalization. The cost of additional prothrombin-time tests was estimated at $19-$50. Patients who received warfarin and an interacting drug had an increased LOS, required more laboratory tests, and had longer prothrombin times than patients given warfarin alone; these differences probably led to higher costs.

Adult↗

Antioxidants in adipose tissue and risk of myocardial infarction: the EURAMIC Study.

Laboratory and epidemiological studies suggest that the antioxidants, vitamin E and beta-carotene, protect against coronary heart disease. In a European multicentre case-control study alpha-tocopherol and beta-carotene concentrations were measured in adipose-tissue samples collected in 1991-92 from 683 people with acute myocardial infarction and 727 controls. Mean adipose-tissue beta-carotene concentration was 0.35 microgram/g in cases and 0.42 in controls, with age-adjusted and centre-adjusted mean difference 0.07 microgram/g (95% confidence interval [CI] 0.04-0.10). Mean alpha-tocopherol concentrations were 193 micrograms/g and 192 micrograms/g for cases and controls, respectively. The age-adjusted and centre-adjusted odds ratio for risk of myocardial infarction in the lowest quintile of beta-carotene as compared with the highest was 2.62 (95% CI 1.79-3.83). Additional control for body-mass index and smoking reduced the odds ratio to 1.78 (95% CI 1.17-2.71); other established risk factors did not substantially alter this ratio. The increased risk was mainly confined to current smokers: the multivariate odds ratio in the lowest beta-carotene quintile in smokers was 2.39 (95% CI 1.35-4.25), whereas it was 1.07 for people who had never smoked. A low alpha-tocopherol concentration was not associated with risk of myocardial infarction. Our results support the hypothesis that high beta-carotene concentrations within the normal range reduce the risk of a first myocardial infarction. The findings for alpha-tocopherol are compatible with previous observations of reduced risk among vitamin E supplement users only. The consumption of beta-carotene-rich foods such as carrots and green-leaf vegetables may reduce the risk of myocardial infarction.

Adipose Tissue↗

Role of glucose and insulin resistance in development of type 2 diabetes mellitus: results of a 25-year follow-up study.

Type 2 diabetes mellitus is characterised by resistance of peripheral tissues to insulin and a relative deficiency of insulin secretion. To find out which is the earliest or primary determinant of disease, we used a minimum model of glucose disposal and insulin secretion based on intravenous glucose tolerance tests to estimate insulin sensitivity (SI), glucose effectiveness (ie, insulin-independent glucose removal rate, SG), and first-phase and second-phase beta-cell responsiveness in normoglycaemic offspring of couples who both had type 2 diabetes. 155 subjects from 86 families were followed-up for 6-25 years. More than 10 years before the development of diabetes, subjects who developed the disease had lower values of both SI (mean 3.2 [SD 2.4] vs 8.1 [6.7] 10(-3) I min-1 pmol-1 insulin; p < 0.0001) and SG (1.6 [0.9] vs 2.3 [1.2] 10(-2) min-1, p < 0.0001) than did those who remained normoglycaemic). For the subjects with both SI and SG below the group median, the cumulative incidence of type 2 diabetes during the 25 years was 76% (95% confidence interval 54-99). By contrast, no subject with both SI and SG above the median developed the disease. Subjects with low SI/high SG or high SI/low SG had intermediate risks. Insulin secretion, especially first phase, tended to be increased rather than decreased in this prediabetic phase and was appropriate for the level of insulin resistance. The development of type 2 diabetes is preceded by and predicted by defects in both insulin-dependent and insulin-independent glucose uptake; the defects are detectable when the patients are normoglycaemic and in most cases more than a decade before diagnosis of disease.

Adolescent↗

Risk of early-onset proliferative retinopathy in IDDM is closely related to cardiovascular autonomic neuropathy.

Determinants of proliferative diabetic retinopathy (PDR) that occur during the 2nd decade of insulin-dependent diabetes mellitus (IDDM) (early-onset PDR) were investigated in a nested case-control study. From an inception cohort of patients with juvenile-onset IDDM that now has 15-21 yr diabetes duration, the patients with PDR (cases, n = 74) were selected for study along with a random sample of the patients in the cohort without PDR (control subjects, n = 88). The risk of PDR was associated with poor glycemic control during the first 12 yr of diabetes. Relative to patients in the first quartile of the index of hyperglycemia, those in higher quartiles and nonattenders had a four- to fivefold risk of developing PDR. A striking relationship with cardiovascular autonomic neuropathy (CAN) was found. Relative to patients without CAN, patients with significant and mild CAN had odds ratios of 77.5 and 34.6, respectively. Patients with albumin excretion rates greater than 30 micrograms/min had moderately increased risk of PDR (ranging from 4-fold for microalbuminuria to 7-fold for proteinuria). In contrast, patients with impaired renal function had an extremely high risk of PDR. All 20 of these patients were cases, therefore the odds ratio was infinite. All three factors (poor glycemic control, CAN, and various stages of nephropathy) were associated with PDR in multiple logistic regression analysis. However, in models including glycemic control, the association between microalbuminuria or proteinuria and PDR was weakened. In conclusion, our findings are consistent with a hypothesis that the level of glycemia is a primary determinant of early-onset PDR.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Familial clustering of insulin sensitivity.

This study's objective was to determine whether there is familial clustering of insulin sensitivity (SI) or insulin-independent glucose uptake (SG), which would be evidence that they are genetically determined traits. Outpatients had a 3-h intravenous glucose tolerance test. Nondiabetic individuals (n = 183), ranging in age from 16 to 60 yr, were from 105 families that had 2 parents with non-insulin-dependent diabetes mellitus. Of these families, 62 contributed 1 offspring, 21 contributed 2, 13 contributed 3, 6 contributed 4, and 2 and 1 contributed 5 and 6, respectively. The minimal model of glucose disposal and the glucose and insulin values from the intravenous glucose tolerance tests were used to estimate SI and SG. The intraclass correlation coefficient was used to compare the within-family variability of SI and SG with the respective between-family distributions. The intraclass correlation coefficients were 0.26 (P = 0.008) for SI and 0.081 (P = 0.45) for SG. SI and SG were uncorrelated (r = -0.059, P = 0.42). The intraclass correlation of SI could not be explained by familial clustering of fasting insulin or ideal body weight. Finally, the 10 families with the lowest values of SI had a significantly higher within-sibship variability of SI than the other 33 families (P less than 0.001, F test). SI but not SG showed familial clustering, which is consistent with a polygenic determinant of SI. In addition, a large within-family variability of SI in some families is compatible with a major gene effect with a dominant mode of inheritance.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Evaluation of six computerized drug interaction screening programs.

Six widely used computerized drug interaction screening programs were evaluated according to criteria developed by a panel of pharmacists. A panel of six pharmacists from various practice settings developed criteria that were used to evaluate six computerized drug interaction screening programs: Medicom Micro Plus, Medical Letter, S-O-A-P, Drug Interactions by Hansten, Drug Therapy Screening Systems (DTSS), and RxTriage. The criteria were that the programs be user friendly and efficient, provide guidance, and be relevant to the user's practice setting. Also, they should detect interactions, quickly alert the user, and guide the user to the appropriate action. The user should be able to set the level of clinical significance, screen only current drugs in a patient profile, and print out summaries. The panel selected nine known drug interactions to test the programs' knowledge bases. Only Medicom Micro Plus and DTSS detected all nine drug interactions; Medical Letter missed three. RxTriage and Drug Interactions received the highest ratings in user friendliness and efficiency, but both missed two interactions. RxTriage was rated most relevant to their practice by hospital and community pharmacists, and Drug Interactions was rated most relevant by faculty practitioners. S-O-A-P received low ratings overall. Of the six drug interaction screening programs evaluated, none was considered by the panel of pharmacists to be ideal.

Data Display↗

Evolving natural history of coronary artery disease in diabetes mellitus.

White diabetic patients are at high risk of developing coronary artery disease (CAD). The natural history of CAD in insulin-dependent (ID) and noninsulin-dependent (NID) diabetes mellitus (DM) is reviewed to gain insight into the mechanisms responsible for the development of premature or accelerated atherosclerosis in diabetic patients. In both IDDM and NIDDM, the risk of CAD increases with lengthening duration of diabetes; the risk, however, does not grow as a constant multiple of the nondiabetic risk of CAD, suggesting that the cumulative exposure to diabetes plays a significant role as a risk factor for CAD only in a subset of patients. This is consistent with the hypothesis that the diabetic milieu has an impact on the progression of atherosclerotic lesions but not on their initiation. This hypothesis is corroborated further by the observation that CAD does not occur in diabetic patients in populations with a low risk of CAD among nondiabetic patients. The component of the diabetic milieu responsible for promotion of atherosclerotic lesions is unknown. There is evidence, however, of a direct or indirect role of hyperinsulinemia in this process.

Adolescent↗

Risk of IDDM in children of diabetic mothers decreases with increasing maternal age at pregnancy.

Offspring of women with insulin-dependent diabetes mellitus (IDDM) have a significantly lower risk of IDDM than the offspring of men with IDDM. Furthermore, a negative association of the risk of IDDM in the offspring with maternal age at delivery has been reported. This study tested the association with maternal age in an independent set of families (n = 103) in which the mother had at least one pregnancy before and after the onset of IDDM. In the 304 offspring, the mean +/- SE risk of IDDM by age 20 was 6.0 +/- 2.4% for those born at maternal ages less than 25 yr, whereas, the risk was significantly lower (0.7 +/- 0.7%) for those born at older maternal ages (P = 0.03). These 304 offspring were combined with a sample of 1391 offspring previously reported for a multivariate analysis of other factors related to pregnancy. In the combined analysis, the risk of IDDM in offspring born at maternal ages greater than 25 yr was one-fifth that for offspring born to younger mothers. The risk of IDDM in the offspring was not significantly related to birth order, mother's age at first pregnancy, or the interval between pregnancies for subsequent ones. The risk for the children born before the mother's onset of diabetes was higher than that for those exposed in utero to her diabetes, but the difference did not reach statistical significance. In conclusion, although genetic factors are important determinants of susceptibility to IDDM, exposure to maternal diabetes protects offspring from IDDM during the first 2 decades of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Slow glucose removal rate and hyperinsulinemia precede the development of type II diabetes in the offspring of diabetic parents.

OBJECTIVE: To determine whether insulin resistance or insulin deficiency is primary in the pathogenesis of type II diabetes. DESIGN: Cohort analytic study of persons with normal glucose tolerance but with a high risk for developing type II diabetes (average follow-up time, 13 years). SETTING: Outpatients had an intravenous glucose tolerance test and were contacted periodically to ascertain diagnoses of diabetes. PARTICIPANTS: One hundred and fifty-five normal offspring, ranging in age from 16 to 60 years, of two parents with type II diabetes and 186 normal control subjects in the same age range who had no family history of diabetes. MEASUREMENTS AND MAIN RESULTS: Two phenotypic characteristics distinguished the offspring of diabetic parents from control subjects. They had slower glucose removal rates (Kg) (P less than 0.01) and higher insulin levels (fasting and during the second phase of insulin response to intravenous glucose; P less than 0.0001) than did control subjects, even after adjustment for differences in obesity. Sixteen percent of the offspring developed type II diabetes. Mean Kg at baseline was 1.7%/min among offspring who subsequently developed diabetes, 2.2%/min among offspring who remained nondiabetic, and 2.3%/min among control subjects. Corresponding means for first-phase insulin were 498, 354, and 373 pM, respectively, whereas second-phase insulin means were 329, 117, and 87 pM, respectively. In multivariate analysis, low Kg and high serum insulin levels independently increased the risk for developing diabetes among the offspring of diabetic parents. CONCLUSIONS: One to two decades before type II diabetes is diagnosed, reduced glucose clearance is already present. This reduced clearance is accompanied by compensatory hyperinsulinemia, not hypoinsulinemia, suggesting that the primary defect is in peripheral tissue response to insulin and glucose, not in the pancreatic beta cell.

Administration, Oral↗