Why Americans eat what they do: taste, nutrition, cost, convenience, and weight control concerns as influences on food consumption

OBJECTIVE

To examine the self-reported importance of taste, nutrition, cost, convenience, and weight control on personal dietary choices and whether these factors vary across demographic groups, are associated with lifestyle choices related to health (termed health lifestyle), and actually predict eating behavior.

DESIGN

Data are based on responses to 2 self-administered cross-sectional surveys. The main outcomes measured were consumption of fruits and vegetables, fast foods, cheese, and breakfast cereals, which were determined on the basis of responses to questions about usual and recent consumption and a food diary.

SUBJECTS/SETTING

Respondents were a national sample of 2,967 adults. Response rates were 71% to the first survey and 77% to the second survey (which was sent to people who completed the first survey).

STATISTICAL ANALYSES

Univariate analyses were used to describe importance ratings, bivariate analyses (correlations and t tests) were used to examine demographic and lifestyle differences on importance measures, and multivariate analyses (general linear models) were used to predict lifestyle cluster membership and food consumption.

RESULTS

Respondents reported that taste is the most important influence on their food choices, followed by cost. Demographic and health lifestyle differences were evident across all 5 importance measures. The importance of nutrition and the importance of weight control were predicted best by subject's membership in a particular health lifestyle cluster. When eating behaviors were examined, demographic measures and membership in a health lifestyle cluster predicted consumption of fruits and vegetables, fast foods, cheese, and breakfast cereal. The importance placed on taste, nutrition, cost, convenience, and weight control also predicted types of foods consumed.

APPLICATIONS

Our results suggest that nutritional concerns, per sc, are of less relevance to most people than taste and cost. One implication is that nutrition education programs should attempt to design and promote nutritious diets as being tasty and inexpensive.

Higher order iminodiacetic acid libraries for probing protein-protein interactions

Higher order iminodiacetic acid diamide trimer (560 compounds) and tetramer libraries (1260 compounds) are described and were assembled in a convergent multistep solution-phase synthesis for use in studying protein-protein interactions.

Is geographic variation in hip fracture rates related to current or former region of residence?

This study examines geographic variation in male and female age-adjusted hip fracture rates in white elderly Medicare enrollees. We assembled a cohort of more than 2 million 1992 enrollees and followed them passively through record linkage for 2 years for a hospitalization containing a diagnostic code indicating hip fracture. We simultaneously estimated rate ratios by region of residence early (inferred from the Social Security number) and late in life. Residence region early in life is associated with substantial variation in hip fracture rates. Conversely, current region has little relation with hip fracture risk.

Contribution of emotionally traumatic events and inheritance to the report of current physical health problems in 4042 Vietnam era veteran twin pairs

OBJECTIVE

To determine the contributions of psychological trauma (exposure to combat during the Vietnam War), genetic factors, childhood experiences shared by twin siblings, and unmeasured experiences not shared by twin siblings to the reporting of current physical health problems a mean of 19 years after military service.

METHODS

In 1987, a national sample of 2224 monozygotic and 1818 dizygotic male veteran members of the Vietnam Era Twin Registry participated in a survey of health. Genetic modeling was performed on cross-sectional physical health and combat exposure data derived from Registry twins.

RESULTS

Combat experiences explained a small proportion (0.7-8.4%) of the variance in the report of hypertension, respiratory conditions, persistent skin conditions, gastrointestinal disorders, joint disorders, and hearing problems. Childhood experiences shared by siblings are not clearly related to any health problem studied. By contrast, genetic factors explain 31 to 54% and noncombat experiences not shared by siblings explain 45 to 66% of the variance in current physical health status.

CONCLUSIONS

Greater than 90% of the variance in reported current physical health problems in Vietnam era veterans is attributable to inherited factors and unmeasured environmental experiences not shared by twin siblings. The traumatic experience of combat makes only a small contribution to the report of current physical health problems. These results do not preclude the possibility that combat influenced the prevalence of illness shortly after military service or that combat may influence the development of illness in the future.

Familial influences on gambling behavior: an analysis of 3359 twin pairs

BACKGROUND

Pathological gambling is becoming an increasing problem in the United States as the number of legalized gambling establishments grows. To examine vulnerability to pathological gambling, we estimated the familial contributions (i.e. inherited factors and/or experiences shared by twin siblings during childhood) to DSM-III-R pathological gambling symptoms and disorder.

METHODS

Data were obtained from a telephone interview performed in 1991-92 utilizing the Diagnostic Interview Schedule Version III-Revised. Interviews were administered to 6718 members of the nationally distributed Vietnam Era Twin Registry of male-male monozygotic and dizygotic twin pairs who served in the military during the Vietnam era.

RESULTS

Inherited factors explain between 35% (95% CI: 28%, 42%) and 54% (95% CI: 39%, 67%) of the liability for the five individual symptoms of pathological gambling behavior that could be estimated statistically. In addition, familial factors explain 56% (95% CI: 36%, 71%) of the report of three or more symptoms of pathological gambling and 62% (95% CI: 40%, 79%) of the diagnosis of pathological gambling disorder (four or more symptoms).

CONCLUSIONS

Familial factors have an important influence on risk for pathological gambling behavior. The increasing access to legalized gambling is likely to result in a higher prevalence of pathological gambling behavior among individuals who are more vulnerable because of familial factors.

Hip fracture incidence among elderly Hispanics

OBJECTIVES

This study estimated hip fracture incidence for elderly Hispanics in the United States.

METHODS

A cohort of Spanish-surnamed 1992 Medicare enrollees was followed for 2 years. Hip fractures were identified by inpatient diagnostic code.

RESULTS

For Hispanic women, the national age-adjusted hip fracture rate was 7.3 per 1000 person-years; for men, the rate was 3.3. Rates varied markedly, with higher rates for the predominantly Mexican-American southwestern states than for Puerto Ricans.

CONCLUSIONS

Nationally, the Hispanic population is at intermediate risk of hip fracture between Blacks and Whites, but geographic variation suggests that Mexican Americans are at higher risk than Puerto Ricans.

Higher order iminodiacetic acid libraries for probing protein-protein interactions

Full details of the preparation of iminodiacetic acid diamide dimer (2040 compounds), trimer (560 compounds), and tetramer (1596 compounds) libraries by multistep convergent solution-phase synthesis for studying protein-protein interactions are provided. The libraries were assembled in a format providing small 8-10 compound mixtures and the deconvolution of many of the small mixtures to identify screening leads by resynthesis of the individual components have been conducted for 320 of the individual compounds to date. A representative example of the subsequent exploration of the structure-activity relationships for an identified receptor binding antagonist (200 additional individual compounds) and steps taken for potential elaboration to a receptor dimerization agonist are defined with preparation of representative linked dimers (70 compounds).

Average African American three-dimensional computed tomography skull images: the potential clinical importance of ethnicity and sex

The production of average 'normative' three-dimensional (3D) computed tomography surface images of the bony skull has only recently been explored. The authors wish to determine the effect of using sex- and ethnicity-specific adult average 3D skull images for comparisons with patient images at various stages of craniofacial surgical management (i.e., diagnosis, treatment planning, prosthetic design, image-guided operative procedures, and outcomes assessment). Craniofacial surgical reconstruction for abnormal patterns of development, cancer resection, or trauma are most likely to benefit from these comparisons. To morphometrically test the significance of separating normative 3D skull data by sex and ethnicity, the authors collected 52 3D, anatomical landmarks from 3D computed tomography scans of dry skulls of 20 Americans of European ethnicity and 20 Americans of primarily African (i.e., primarily African and some European) ethnicity. A Procrustes-based morphometric analysis of shape detects 1.2 times as much interethnic variance as intersex variance. The African American sample presents 4.2% more dolichocephaly, wider orbits, flatter nasal area, larger gnathic anatomy, and more procumbent dentition. Pooling the sexes across both groups, it is seen that men tend to have less bulbous crania, more protruding brows, noses, and masticatory muscle attachments, and relatively less protrusive palettes and anterior mandibles. Despite a small sample size (N = 40), the authors' results are statistically significant (P approximately 0.001 overall) for both of the main factors, sex and ethnicity, separately.

[Presence of acinar pancreas in reflux esophagitis and Barrett's esophagus]

Pancreatic metaplasia in Barrett's esophagus was originally described by Krishnamurthy et al. They found that these focal clusters of cells resemble pancreatic acinar cells by immunohistochemistry and electron microscopy. Wang et al one year later, described these same cell clusters in normal and inflamed gastroesophageal junction. We studied 318 cases diagnosed as Barrett's esophagus (199 cases) and chronic esophagitis (119 cases) in the ABC Medical Center seen in 1996 and the first four months of 1997, to look for pancreatic acinar metaplasia. We found 14 cases of Barrett's esophagus and 11 cases of chronic esophagitis with pancreatic acinar metaplasia. By immunohistochemistry and electron microscopy that these cell clusters are actually acinar pancreatic cells. Our results are in keeping with those found by Krishnamurthy and Wang that the clusters represent pancreatic acinar cells and may be found in Barrett's esophagus and in chronic esophagitis. The significance of these findings remain to be elucidated.

Modelling ordinal responses from co-twin control studies

The co-twin control design has been widely used in studying the effects of environmental factors on the development of diseases. For binary outcomes that arise from co-twin control studies, the conditional likelihood method is commonly used. This approach, however, does not readily extend to ordinal response data because the standard conditional likelihood does not exist for cumulative logit or proportional odds models. In this paper, we investigate the applicability of the random-effects and GEE approaches in analysing ordinal response data from co-twin control studies. Using both approaches, we re-analyse data from a co-twin control study of the impact of military services during the Vietnam era on post-traumatic stress disorders (PTSD). The ordinal models have considerably increased power in detecting the effects of exposure when compared to the analyses using a dichotomized response. We discuss the interpretation of the estimates from GEE and random-effect models in the context of the twin data.

A registry-based twin study of depression in men

BACKGROUND

The only large, registry-based twin study of depression using diagnostic criteria assessed by structured interview included only women. We present results from a comparable study of men.

METHODS

Data were collected using a standardized telephone interview of men from the Vietnam Era Twin Registry. Both twins from 3372 pairs participated. Proband-wise concordance rates and biometric modeling were used to analyze the data.

RESULTS

The diagnosis of major depression (MD), as defined by DSM-III-R, and the subtype of severe/psychotic MD were significantly affected by genetic (h2=0.36 and 0.39, respectively) and nonshared environmental (e2=0.64 and 0.61, respectively) factors but not by family environmental factors. Dysthymia and mild and moderate MD were affected by family environmental (c2=0.27, 0.08, and 0.14, respectively) and nonshared environmental (e2=0.73, 0.92, and 0.86, respectively) factors but not by genetic factors. Early-onset (before age 30 years) and late-onset (after age 30 years) MD were significantly affected by genetic (h2=0.47 and 0.10, respectively) and nonshared environmental (e2=0.53 and 0.90, respectively) factors. Early-onset MD was significantly more heritable than late-onset MD.

CONCLUSIONS

The magnitude of genetic and environmental effects on depression in men is similar to that previously reported in women. Also similar to previous findings, more severe and earlier-onset depression may be more strongly affected by genetic factors, but differences in the reliability of reports of depression associated with severity may inflate estimates of the effect of the unique environment and deflate heritability estimates for less severe depression.

Long-term reliability and validity of alcoholism diagnoses and symptoms in a large national telephone interview survey

The long-term reliability and validity of telephone lay interview assessments of alcoholism were examined in the context of a large national community-based survey of over 8,000 male Vietnam era veterans. A subsample of 146 men was interviewed twice by telephone using the same structured interview an average of 15 months apart to evaluate the long-term reliability of alcoholism symptoms and diagnoses. In addition, a search of Department of Veterans Affairs patient treatment files of inpatient hospitalizations between 1970 and 1993 yielded a subsample of 89 interviewed men with a past discharge diagnosis of alcohol dependence. The test-retest reliability of alcohol abuse and alcohol dependence diagnoses was good, with kappa coefficients of 0.74 and 0.61, respectively. The reliability of individual alcoholism symptoms was fair to good, with kappas of 0.46 to 0.67. Ninety-six percent of individuals identified by Department of Veterans Affairs patient treatment files as having an alcohol dependence diagnosis were correctly diagnosed by the telephone interview. The results of the present study provide additional evidence for the long-term reliability and validity of lifetime alcoholism diagnoses, and suggest that the reliability and validity of telephone interview assessments of alcoholism are as good as that of an in-person interview. Telephone administration of structured psychiatric interviews appears to be an attractive alternative to in-person interviewing for gathering information about alcoholism and alcohol-related problems.

Comparison of population-averaged and subject-specific approaches for analyzing repeated binary outcomes

Several approaches have been proposed to model binary outcomes that arise from longitudinal studies. Most of the approaches can be grouped into two classes: the population-averaged and subject-specific approaches. The generalized estimating equations (GEE) method is commonly used to estimate population-averaged effects, while random-effects logistic models can be used to estimate subject-specific effects. However, it is not clear to many epidemiologists how these two methods relate to one another or how these methods relate to more traditional stratified analysis and standard logistic models. The authors address these issues in the context of a longitudinal smoking prevention trial, the Midwestern Prevention Project. In particular, the authors compare results from stratified analysis, standard logistic models, conditional logistic models, the GEE models, and random-effects models by analyzing a binary outcome from two and seven repeated measurements, respectively. In the comparison, the authors focus on the interpretation of both time-varying and time-invariant covariates under different models. Implications of these methods for epidemiologic research are discussed.

Attitudes about genetic risk of couples undergoing in-vitro fertilization

Many couples undergoing in-vitro fertilization (IVF) are at a higher risk of having a child with a genetic abnormality. In a sample of 55 consecutive couples starting IVF, only 33% had no genetic risk factor. The most common genetic risks were advanced maternal age and possible abnormalities associated with severe male infertility. Despite education on these risks, 71% of couples had no interest in receiving formal genetic counselling. Only 14% of couples at risk would consider using a gamete donor to avoid transmitting a genetic disorder to a child. The triple test to screen for fetal abnormalities was acceptable to 82% of couples, but only 47% planned to have amniocentesis or chorionic villi sampling. Couples were significantly more likely to opt for prenatal testing if they would consider terminating a pregnancy should the fetus have a severe genetic abnormality (P < 0.01). Roman Catholic couples tended to have more conservative attitudes about pregnancy termination. Socio-economic status and whether the infertility factor was male or female were not predictors of a couple's attitudes.

[Doxycycline-induced esophageal ulcers]

Tetracycline is known as one of the antibiotics that induce esophageal ulcers.

PURPOSE

Understand how these ulcers may behave and respond to treatment with sucralfate.

METHOD

During the last two years we studied all patients complaining of dysphagia and odinophagia with an upper GI endoscopy, who were taking doxycycline in the last few days. All of them discontinued the drug once the diagnosis was done and most of them were treated also with sucralfate, 1 g tid.

RESULTS

Eleven patients took doxycycline prescribed for: pelvic inflammatory disease, acne, urinary tract and pulmonary infections. Odinophagia was the most common symptom over the next few days of treatment with some risk factors previously documented, such as taking pills just before bedtime and with a small amount of water. The esophageal ulcers were multiple and located mainly in the middle esophageal third. Symptoms disappeared 3.7 days after the medication was stopped, while those taking sucralfate did not change the period of symptoms.

CONCLUSIONS

Physicians must be aware of the doxycycline induced esophageal ulcers and discontinuation of the antibiotic as the main treatment, while sucralfate even though has shown to cover these ulcers, does not change the outcome. Therefore, they must encourage then patients to take the pills with enough liquid, in supine position and have special attention to the elderly and those with any kind of esophageal disease.

Mechanisms of asbestos-induced nitric oxide production by rat alveolar macrophages in inhalation and in vitro models

To evaluate the contribution of reactive nitrogen species to inflammation by asbestos, Fischer 344 rats were exposed to crocidolite or chrysotile asbestos by inhalation to determine whether increases occurred in nitric oxide (NO.) metabolites from alveolar macrophages (AMs). AMs from animals inhaling asbestos showed significant elevations (p < .05) in nitrite/nitrate levels which were ameliorated by NG-monomethyl-L-arginine (NMMA), an inhibitor of inducible nitric oxide synthase (iNOS) activity. Temporal patterns of NO. generation from AMs correlated with neutrophil influx in bronchoalveolar lavage samples after asbestos inhalation or bleomycin instillation, another model of pulmonary fibrosis. To determine the molecular mechanisms and specificity of iNOS promoter activation by asbestos, RAW 264.7 cells, a murine macrophage-like line, and AMs isolated from control rats were exposed to crocidolite asbestos in vitro. These cells showed increases in steady-state levels of iNOS mRNA in response to asbestos and more dramatic increases in both iNOS mRNA and immunoreactive protein after addition of lipopolysaccharide (LPS). After transfection of an iNOS promoter/luciferase reporter construct, RAW 264.7 cells exposed to LPS, crocidolite asbestos and its nonfibrous analog, riebeckite, revealed increases in luciferase activity whereas cristobalite silica had no effects. Studies suggest that NO. generation may be important in cell injury and inflammation by asbestos.

Genetic and environmental contributions to smoking

We estimate the magnitude of genetic and shared environmental contributions to risk of initiation and maintenance of smoking. Genetic models were fitted to data from 2,204 male-male monozygotic and 1,793 male-male dizygotic twin pairs from the Vietnam Era Twin Registry who responded to smoking questions on a 1987 mail and telephone survey. The best fitting model allowed for both genetic and shared environmental effects on smoking initiation, accounting for 50% and 30% of the variance in risk, but allowed for only genetic effects, (accounting for 70% of the variance in risk), on persistence in smoking among those who had become regular smokers. This finding of a major genetic influence on smoking persistence confirms similar results from studies in Scandinavia and Australia. The role of heritable traits such as nicotine sensitivity should be addressed in smoking prevention and cessation efforts.

Structure of the guanine nucleotide exchange factor Sec7 domain of human arno and analysis of the interaction with ARF GTPase

Sec7-related guanine nucleotide exchange factors (GEFs) initiate vesicle budding from the Golgi membrane surface by converting the GTPase ARF to a GTP-bound, membrane-associated form. Here we report the crystal structure of the catalytic Sec7 homology domain of Arno, a human GEF for ARF1, determined at 2.2 angstroms resolution. The Sec7 domain is an elongated, all-helical protein with a distinctive hydrophobic groove that is phylogenetically conserved. Structure-based mutagenesis identifies the groove and an adjacent conserved loop as the ARF-interacting surface. The sites of Sec7 domain interaction on ARF1 have subsequently been mapped, by protein footprinting experiments, to the switch 1 and switch 2 GTPase regions, leading to a model for the interaction between ARF GTPases and Sec7 domain exchange factors.

Efficacy and safety of the new antiandrogenic oral contraceptive Belara

The aim of this open, noncontrolled phase III study was the assessment of the contraceptive efficacy and the evaluation of the safety of long-term use of Belara (30 micrograms ethinyl estradiol plus 2 mg chlormadinone acetate). Furthermore, cycle stability during administration of Belara and the influence of Belara on acne and seborrhea as clinical signs of androgenization were observed. Belara was taken by 1655 women for a total of 22,337 cycles. For the theoretical Pearl index, a value of 0.269 (95% CI [0.109, 0.600]) was calculated. In 1655 of 22,337 cycles (7.4%), no withdrawal bleeding was documented, whereas in 2565 of 22,308 cycles (11.5%), spottings and, in 786 of 22,308 cycles (3.5%), breakthrough bleeding occurred. After the intake of Belara for 12 cycles, acne on the face/neck improved in 64.1% of the women (209 of 326). In 53.4% of the women (175 of 326), acne disappeared completely. Seborrhea improved after 12 cycles in 89 of 131 women (67.9%), of whom 76 women (58.0%) were completely cured. Sixty-two serious adverse events (SAE) occurred in 59 of 1655 women. Accidents and injuries of the musculoskeletal system were the SAE with the highest incidence (0.66%). Two cases of deep venous thrombosis, one pulmonary embolism, and two cases of visual disturbances were observed. Only for the two cases of deep venous thrombosis could a relation to Belara be assumed. Of the adverse events commonly reported for oral contraceptives, headache was observed for the first time under study medication in 37.4%, nausea in 23.1%, breast tenderness in 21.7%, and vaginal discharge in 19.4% of the women. The frequency of adverse events decreased with longer duration of a drug consisting of intake of Belara. In conclusion, Belara can be described as an effective and safe oral contraceptive with marked antiandrogenic properties.

Importance of reactive oxygen species in the peritoneal fluid of women with endometriosis or idiopathic infertility

OBJECTIVE

To determine whether reactive oxygen species in peritoneal fluid might be a factor in infertility.

DESIGN

Prospective study.

SETTING

Andrology laboratory and gynecology clinic at a tertiary care facility.

PATIENT(S)

Women with endometriosis (n = 15) or idiopathic infertility (n = 11) who underwent laparoscopy for infertility. Patients undergoing tubal ligation served as controls (n = 13).

INTERVENTION(S)

Aspiration of peritoneal fluid.

MAIN OUTCOME MEASURE(S)

Reactive oxygen species levels, presence of polymorphonuclear granulocytes, and leukocyte distribution in peritoneal fluid.

RESULT(S)

Reactive oxygen species were present in the peritoneal fluid of patients with endometriosis, idiopathic infertility, and tubal ligation. Levels of reactive oxygen species did not show a statistically significant difference between patients with endometriosis and the control group in either unprocessed or processed (cell-free) peritoneal fluid, but did differ significantly between patients with idiopathic infertility and controls in processed peritoneal fluid. Polymorphonuclear granulocytes (> 1 x 10(6)/mL) were not present in the peritoneal fluid of any patient. Macrophage concentrations of peritoneal fluid did not differ significantly between controls and patients with endometriosis or idiopathic infertility.

CONCLUSION(S)

Reactive oxygen species in the peritoneal fluid may not affect fertility directly in women with endometriosis; however, they may have a role in patients with idiopathic infertility.

Role of extracellular signal-regulated protein kinases in apoptosis by asbestos and H2O2

Stimulation of cell signaling cascades by oxidants may be important in the pathogenesis of pulmonary and pleural diseases. Here, we demonstrate in rat pleural mesothelial cells that apoptotic concentrations of crocidolite asbestos and H2O2 induce phosphorylation and activation of extracellular signal-regulated protein kinases (ERK). Activation of c-jun-NH2-terminal protein kinases (JNK)/stress-activated protein kinases was also observed in response to H2O2. In contrast, asbestos caused more protracted activation of ERK without JNK activation. Both H2O2- and asbestos-induced activation of ERK was abolished by catalase. Moreover, chelation of surface iron from crocidolite fibers or addition of N-acetyl-L-cysteine prevented ERK activation and apoptosis by crocidolite, indicating an oxidative mechanism of cell signaling. The MEK1 inhibitor PD-98059 abrogated asbestos-induced apoptosis, confirming a causal relationship between ERK activation and apoptosis. These results suggest that distinct cell-signaling cascades may be important in phenotypic responses elicited by oxidant stresses.