Alcohol consumption and insulin concentrations. Role of insulin in associations of alcohol intake with high-density lipoprotein cholesterol and triglycerides

BACKGROUND

The relation between alcohol intake and insulin levels may explain, in part, the reported associations of alcohol with cardiovascular disease risk factors, including high-density lipoprotein (HDL) cholesterol, triglycerides, blood pressure, and glucose levels, each of which has been recognized as a component of the insulin resistance syndrome.

METHODS AND RESULTS

Subjects included nondiabetic participants of the Kaiser Permanente Women Twins Study (1989 through 1990). Usual alcohol intake was assessed as part of a food frequency questionnaire. For women from twin pairs in which both twins drank (n = 338), an increment of 12 g of alcohol per day (about one drink) was associated with an 8% lower 2-hour post-glucose-load insulin (P < .01) in a multiple regression analysis for twin data, adjusted for age, body mass index, waist-to-hip ratio, total caloric intake, and family history of diabetes. With genetic influences removed by matched analysis of the subset of 98 monozygotic twin pairs, an intrapair difference of 12 g of alcohol per day was associated with a 12.4% intrapair decrement in postload insulin (P < .01). Inverse associations were also seen for fasting insulin. Alcohol consumption was inversely associated with postload glucose but not with fasting glucose in unmatched (P = .05) and matched (P = .005) analyses. A significant positive association of alcohol intake with high-density lipoprotein cholesterol and an inverse relation of alcohol intake with triglycerides were each independent of insulin levels (P < or = .02 in the matched models). Neither systolic nor diastolic blood pressures were related to alcohol consumption in this sample, perhaps because of the rather low level of alcohol intake in the study population (median, 4 g/d).

CONCLUSIONS

Within the range of light to moderate drinking habits, alcohol consumption was inversely related to fasting and postload insulin levels. This relation did not explain associations of alcohol intake with lipid levels and may instead reflect an additional mechanism by which moderate alcohol consumption impacts cardiovascular disease risk.

Usual dietary fat intake and insulin concentrations in healthy women twins

OBJECTIVE

To evaluate the associations between the usual intake of dietary fats and insulin concentrations. Insulin concentrations and insulin resistance have been positively related to risk for NIDDM, obesity, hypertension, dyslipidemia, and coronary heart disease, yet little is known of the environmental risk factors for relative hyperinsulinemia. Insulin resistance can be induced by high-fat feeding in laboratory animals; therefore, high-fat diets may increase risks for developing NIDDM.

RESEARCH DESIGN AND METHODS

Subjects included 544 nondiabetic women who participated in the second examination of the Kaiser Permanente Women Twins Study (1989-1990). Fasting and 2-h post 75-g glucose load insulin levels were determined. Dietary fat intake was assessed by a food frequency questionnaire. Generalized least-squares regression analyses for unpaired twin data were used to determine the relationship between dietary fat intake and insulin levels after adjustment for total calories, age, several behavioral variables, and in some models, percentage of body fat and waist-to-hip ratio. Associations of dietary fat intake with insulin levels were also evaluated within the subset of monozygotic twin pairs (n = 164 pairs) after removal of genetic influences by regression analysis of intrapair differences.

RESULTS

Among the 544 individual women, a 20 g/day increase in total dietary fat was associated with a higher fasting insulin level (9% [P < 0.001] before and 6% [P < 0.01] after adjustment for the obesity variables). Higher intakes of saturated fat, oleic acid, and linoleic acid were each positively related to higher fasting insulin values. The relation of dietary fat with fasting insulin was significantly attenuated among physically active women compared with those who were sedentary (P = 0.04), even after adjustment for obesity. Only saturated fat intake was significantly associated with 2-h postglucose load insulin level before (P = 0.004) but not after adjustment for obesity. Within identical twin pairs, total dietary fat was positively related to fasting insulin before (P = 0.03) but not after adjustment for obesity (P = 0.11).

CONCLUSIONS

High intake of total dietary fat is positively related to relative fasting hyperinsulinemia in nondiabetic women, particularly those who are sedentary. This effect appears to be partly mediated by the relation of dietary fat with obesity.

LDL subclass phenotypes and the insulin resistance syndrome in women

BACKGROUND

Low-density lipoprotein (LDL) subclass phenotype B, characterized by predominance of small, dense LDL particles, is associated with elevated plasma triglycerides and apolipoprotein B and with lower high-density lipoprotein (HDL) cholesterol and apolipoprotein A-I. Because these abnormalities resemble the dyslipidemia of insulin resistance, we examined associations of LDL subclass phenotype with plasma insulin levels and with other aspects of the insulin resistance syndrome.

METHODS AND RESULTS

LDL subclass phenotypes were determined by gradient gel electrophoresis in 682 female twins aged 30 to 91 years who participated in the second examination of the Kaiser Permanente Women Twins Study. Prevalence of phenotype B and the intermediate phenotype (I) increased strongly with age, obesity, and non-insulin-dependent diabetes. In multivariate analysis of nondiabetic women, phenotype B or I was independently associated with each aspect of the insulin resistance syndrome, including higher plasma triglycerides, waist-hip ratio, fasting and postload insulin levels, and systolic blood pressure and lower HDL cholesterol levels after adjustment for age and body mass index. The prevalence of phenotype B or I rose progressively from 5.6% in women with no manifestations of the insulin resistance syndrome to 100% in women with four syndrome components. In 25 nondiabetic, monozygotic twin pairs discordant for subclass phenotype, the twins with phenotype B (or I) had significantly higher levels of body mass index, waist-hip ratio, and systolic blood pressure than their twins with phenotype A. Thus, nongenetic variation in these risk factors is important in explaining their associations with LDL subclass phenotype.

CONCLUSIONS

Small, dense LDL is an integral feature of the insulin resistance syndrome. Nongenetic (ie, behavioral or environmental) factors are important for the expression of the phenotype and for its association with other heart disease risk factors.

Transplantation and the pediatric chest

The plain chest radiograph is the mainstay in the imaging assessment of the chest in a prospective organ recipient and is invaluable in the initial evaluation of posttransplant complications. Although the presence of focal or diffuse air-space disease on a chest radiograph is often nonspecific, this finding helps direct the choice of other diagnostic methods. Among cross-sectional imaging techniques, computed tomography is used most often to further define anatomy and abnormal findings and to guide needle biopsy or aspiration if necessary. A variety of posttransplant complications are discussed, including common postoperative findings, pulmonary infection, and organ rejection.

Telltale signs of congenital heart disease

There are several key plain film findings that raise suspicion for and aid in the differentiation of congenital heart defects. These 'telltale' signs and their significance and the additional necessary imaging studies of cardiac lesions are discussed with particular emphasis on the role of magnetic resonance imaging.

Genetics of LDL subclass phenotypes in women twins. Concordance, heritability, and commingling analysis

Low density lipoprotein (LDL) subclass phenotype B, characterized by a predominance of small LDL as determined by gradient gel electrophoresis, has been associated with increased risk of coronary heart disease and an atherogenic lipoprotein profile. Previous studies employing complex segregation analysis have demonstrated a major, single gene effect on the inheritance of this phenotype in families. Recently, linkage between this phenotype and variation at the LDL receptor locus on chromosome 19 has been reported. However, variation in LDL subclass phenotypes has also been associated with age, gender, diabetes status, beta-blocker medication, and diet. The present study further evaluates the relative importance of genetic and nongenetic influences on LDL subclass phenotypes and on LDL peak particle diameter (as a reflection of the size of the major LDL subclass) in monozygotic and dizygotic women twin pairs. The analysis is based on 203 monozygotic and 145 dizygotic pairs of adult female twins who participated in the second examination of the Kaiser Permanente Women Twins Study. The average age was 51 years at this exam and 90% were white. Concordance analysis revealed that monozygotic cotwins shared LDL subclass phenotypes more frequently than dizygotic cotwins, and this was confirmed using logistic regression analysis after controlling for potential confounding factors. Heritability analyses suggested that approximately one third to one half of the variation in LDL peak particle diameter, a continuous variable reflecting LDL size, could be attributed to genetic influences. Commingling analysis of the frequency distribution of LDL peak particle diameter identified three distinct subgroups of subjects, one of which corresponded to those subjects with LDL subclass phenotype B.(ABSTRACT TRUNCATED AT 250 WORDS)

Nodules, masses, and pseudomasses in the pediatric lung

The vast majority of pulmonary masses in children are nonmalignant. Most pediatric nodular disease is granulomatous in origin. Infections and congenital lesions outnumber neoplastic lesions. Pulmonary metastatic disease most often results from Wilms' tumor and is followed in frequency by the sarcomas. Primary pulmonary malignancy is rare in the child.

Nurses ... bridging the gap: Australian aboriginals and primary health care

This paper outlines a clinical learning experience designed to provide nursing students with experience in working with the Australian Aboriginal people. It also provided an opportunity for the concepts of primary health care from the rural perspective to be observed and experienced. Walgett is 433 miles or 694 kilometers from Sydney and situated in the north west of the state of New South Wales (NSW). Australia, being a large continent of some 7,682,300 square kilometers or 2,966,153 square miles, is divided into 7 states, of which New South Wales is the most populated (National Geographic Atlas of the World, 1981).

Effect of four combined oral contraceptives on blood pressure in the pill-free interval

OBJECTIVE

To evaluate blood pressure changes in the pill-free interval and from baseline among women taking four different low-dose monophasic oral contraceptives.

DESIGN

131 women were randomized to four different oral contraceptives. Pressures were obtained at baseline, at the end of treatment cycles and at the end of the 7 pill-free days, during 6 months of treatment. Pressures were obtained at 4 and 8 weeks after discontinuation. Group 1 received norethisterone acetate 1000 micrograms, group 2 received levonorgestrel 150 micrograms, group 3 received desogestrel 150 micrograms, and group 4 received gestodene 75 micrograms, all combined with ethinyloestradiol 30 micrograms.

RESULTS

All four groups showed an increase in pressure during treatment, with return to baseline levels four weeks after treatment. At the end of the pill-free interval, the readings did not differ significantly from on treatment except for women in Group 4, who experienced an increase in diastolic pressure.

CONCLUSIONS

Use of the four oral contraceptives was associated with a small increase in systolic and diastolic pressure. Whatever mechanism causes the increase is not entirely reversible by 7 days without treatment.

Dopaminergic inhibition of DNA synthesis in pituitary tumor cells is associated with phosphotyrosine phosphatase activity

Dopaminergic D2 receptor agonists, such as bromocriptine, are potent anti-proliferative agents in the treatment of human pituitary adenomas. We have reproduced the anti-proliferative effect of dopamine in an established pituitary cell line stably transfected with the rat D2 dopamine receptor cDNA. We found that dopaminergic inhibition of DNA synthesis parallels the stimulation of a phosphotyrosine phosphatase activity. Both actions are blocked by pertussis toxin and by the phosphotyrosine phosphatase inhibitor, vanadate. We suggest that the anti-proliferative action of dopamine is mediated, at least in part, by the dopaminergic stimulation of a phosphotyrosine phosphatase.

Who will relapse? Symptoms of nicotine dependence predict long-term relapse after smoking cessation

Results of a prospective examination (N = 618) of factors associated with smoking relapse are reported. At 1-year follow-up, a modified version of the Fagerstrom Tolerance Questionnaire (Dependence Index; DI) and a measure of craving entered the logistic model (odds ratio of 2.7 [p less than .001]). At Year 2, only the DI entered the model (odds ratio of 2.2 [p less than .001]). The ability of signal detection analysis (SDA) to produce clinically useful decision rules was also examined. At Year 1, SDA produced 1 subgroup with a 25% nonrelapse rate and another with a 9% nonrelapse rate (odds ratio of 3.4 [p less than .001]). At Year 2, SDA produced 1 subgroup with a nonrelapse rate of 19% and another with a nonrelapse rate of 7% (odds ratio of 3.0 [p less than .001]). The use of signal detection methods may help clinicians to identify those at greater or lesser risk of relapse.

Lipoprotein(a) in women twins: heritability and relationship to apolipoprotein(a) phenotypes

Lp(a) is a unique lipoprotein consisting of an LDL-like particle and a characteristic protein, apo(a). Increased levels of Lp(a) constitute a risk factor for coronary heart disease. Variation in the size of the apo(a) protein is a phenotype controlled by the apo(a) gene on chromosome 6 and is related to Lp(a) plasma levels. Based on 169 MZ and 125 DZ adult female twin pairs, this study's purpose was to estimate the proportion of the variation in Lp(a) levels that is due to genetic influences and to determine the extent to which the apo(a) locus explains this heritability. Lp(a) levels were significantly more similar in MZ twins than in DZ twins: mean co-twin differences were 3.9 +/- 5.7 mg/dl and 16.0 +/- 19.9 mg/dl (P less than .001), respectively. Intraclass correlations were .94 in MZ twins and .32 in DZ twins, resulting in a heritability estimate of .94 (P less than .001). Heritability was then calculated using only co-twins with the same apo(a) phenotype: the heritability estimate decreased to .45 but was still highly significant (P less than .001). Therefore, on the basis of heritability analysis of women twins, Lp(a) levels are almost entirely genetically controlled. Variation at the apo(a) locus contributes to this heritability, although other genetic factors could be involved.

The influence of social and political violence on the risk of pregnancy complications

BACKGROUND

Events in Chile provided an opportunity to evaluate health effects associated with exposure to high levels of social and political violence.

METHODS

Neighborhoods in Santiago, Chile, were mapped for occurrences of sociopolitical violence during 1985-86, such as bomb threats, military presence, undercover surveillance, and political demonstrations. Six health centers providing prenatal care were then chosen at random: three from "high-violence" and three from "low-violence" neighborhoods. The 161 healthy, pregnant women due to deliver between August 1 and September 7, 1986, who attended these health centers were interviewed twice about their living conditions. Pregnancy complications and labor/delivery information were subsequently obtained from clinic and hospital records.

RESULTS

Women living in the high-violence neighborhoods were significantly more likely to experience pregnancy complications than women living in lower violence neighborhoods (OR = 5.0; 95% CI = 1.9-12.6; p less than 0.01). Residence in a high-violence neighborhood was the strongest risk factor observed; results persisted after controlling for several sets of potential confounders.

CONCLUSION

Living in areas of high social and political violence increased the risk of pregnancy complications among otherwise healthy women.

Who will relapse? Symptoms of nicotine dependence predict long-term relapse after smoking cessation

Results of a prospective examination (N = 618) of factors associated with smoking relapse are reported. At 1-year follow-up, a modified version of the Fagerstrom Tolerance Questionnaire (Dependence Index; DI) and a measure of craving entered the logistic model (odds ratio of 2.7 [p less than .001]). At Year 2, only the DI entered the model (odds ratio of 2.2 [p less than .001]). The ability of signal detection analysis (SDA) to produce clinically useful decision rules was also examined. At Year 1, SDA produced 1 subgroup with a 25% nonrelapse rate and another with a 9% nonrelapse rate (odds ratio of 3.4 [p less than .001]). At Year 2, SDA produced 1 subgroup with a nonrelapse rate of 19% and another with a nonrelapse rate of 7% (odds ratio of 3.0 [p less than .001]). The use of signal detection methods may help clinicians to identify those at greater or lesser risk of relapse.

Imaging of the pediatric cardiovascular system

Magnetic resonance imaging has become increasingly useful in the assessment of pediatric congenital heart disease. Spin-echo, gradient-echo, and cine techniques allow for both anatomic and functional cardiac assessment. MR imaging has proven most valuable in assessing complex heart disease and in visualizing areas that are sometimes poorly seen on echocardiographic studies. In particular, the anatomy of the aorta, central pulmonary arteries, and veins are usually well defined on MR imaging. Duplex and color Doppler sonography have become indispensable for evaluating the major vessels of the abdomen. The presence of clot, and quantity and quality of vascular flow as well as changes over time and response to therapy are readily assessed. Pulmonary sequestration is just one example of the burgeoning utility of duplex and color Doppler sonography in evaluating abdominal, mediastinal, and juxta-diaphragmatic masses. Sonography shows promise as a simple and accurate method for rapidly identifying the aberrant systemic blood supply in suspected cases of sequestered lung.

Pancreatic ductal abnormalities in children

From 1979 to 1990, 33 children required operative treatment for pancreatitis. Causes included ductal abnormalities (12 children), trauma (10 children), idiopathic (four children), gallstones (three children), drug-induced (three children), and tumor (one child). This study reviews the characteristics and outcome of the 12 children with ductal abnormalities. Symptoms were present up to 9 years or less before diagnosis, with two patients undergoing negative appendectomies. At diagnosis, amylase levels averaged 612 IU/L and lipase, 4761 IU/L. Preoperative studies included ultrasonography (11 children), endoscopic retrograde cholangiopancreatography (nine children), and computerized tomography (six children). Intraoperative cholangiopancreatography was performed in nine patients and was essential in four to diagnosis their anomaly. Patients were categorized into those with a common channel (three children), ampullary stenosis (two children), ductal fusion error (one child), or combinations (six children). Operations included sphincteroplasty (seven patients), pancreaticobiliary separation (six patients), pancreatic duct enterostomy (three patients), and distal pancreatectomy (one patient). Three patients required more than one procedure to repair the combination anomalies. Symptoms resolved immediately in nine patients. Two patients had delayed resolution, with one patient requiring the addition of somatostatin. One patient was lost to follow-up. Recurrent or protracted pancreatitis, without obvious cause, requires expeditious endoscopic retrograde cholangiopancreatography and/or intraoperative cholangiopancreatography. Operative therapy should be tailored to ductal anatomy and will resolve symptoms in most children.

Expression and functional characterization of a soluble form of vascular cell adhesion molecule 1

Vascular cell adhesion molecule 1 (VCAM1) is a leukocyte adhesion molecule induced on human endothelium in vitro and in vivo by inflammatory stimuli. A truncated cDNA for VCAM1 was constructed, stably expressed in Chinese Hamster Ovary (CHO) cells, and the secreted recombinant soluble form of VCAM1 (rsVCAM1) purified to homogeneity by immunoaffinity chromatography. Immobilized rsVCAM1 is a functional adhesion protein, and selectively binds only VLA4-expressing cells, including human B and T lymphocytes, NK cells, and certain lymphoblastoid cell lines. T cell subset analyses indicate preferential binding of CD8+ memory cells. rsVCAM1 should prove valuable for the further study of the role of VCAM1 during inflammatory and immune responses in vivo.