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Lessons from in vitro perifusion of pancreatic islets isolated from 80 human pancreases.

We report the average insulin response to acute glucose measured by in vitro perifusion of pancreatic islets isolated from 80 consecutive human organs. Different perifusion parameters were considered [basal release, stimulation index (SI), time to peak, incremental area under the curve delta-AUC alpha)], and the correlation among them was determined. SI positively correlated with delta-AUC alpha (p < 0.001, r = 0.80) while negatively with time to peak (p < 0.05, r = -0.23). We also evaluated several variables of the isolation procedure that might affect responsiveness to glucose by human islets. Sex and age of pancreas donors, cold ischemia time, duration of the digestion, collagenase concentration, and lot characteristics (collagenase, trypsin, clostripain, and proteases activity), and final islet yield were considered. Multivariate regression analysis showed only an independent association between SI and the concentration of collagenase (p = 0.01).

Adolescent↗

Dietary intake of fruits, vegetables, and fat in Olmsted County, Minnesota.

OBJECTIVE: To assess self-reported dietary intake in the adult population of Olmsted County, Minnesota. SUBJECTS AND METHODS: We conducted a random-digit-dial telephone survey between March 1 and April 21, 1999, of 1232 adults residing in Olmsted County, Minnesota. We then mailed a structured questionnaire to the survey respondents and achieved a response rate of 732 individuals. Percentages of individuals and predictors of those who meet recommendations for intake of fruits and vegetables and for dietary fats were determined by using chi2 tests of general association and multivariate logistic regression. RESULTS: Only 16% of the population of Olmsted County reported meeting standard dietary recommendations for consuming both 5 or more servings of fruits and/or vegetables per day and no more than 30% of calories from fat. Fifty-one percent of the population was meeting neither recommendation. Women were more likely than men to report meeting both goals (22% vs 8%, P<.001), but still more women were meeting neither goal than were meeting both goals (40% vs 22%, P<.001). Multivariate logistic regression revealed the following factors to predict adherence to both goals: female sex, lower body mass index, nonsmoker, history of high cholesterol, and daily physical activity. CONCLUSION: Few individuals in Olmsted County are meeting national recommendations for intake of fruits, vegetables, and dietary fat. More effective interventions are needed to improve dietary habits in all subgroups of this community.

Adult↗

Smoking behavior among adolescents in the city, suburbs, and rural areas of Shanghai.

PURPOSE: The study was designed to investigate differences in predisposing factors, enabling factors, reinforcing factors, and smoking behavior among middle school students living in the city, suburbs, and rural areas of Shanghai. DESIGN: A one-time cross-sectional survey design was applied in this study. SETTING: The study was conducted in 11 schools in three areas. SUBJECTS: A total number of 1116 students from these three areas participated in this study. The response rates were 92, 88, and 84% for city, suburbs, and rural areas, respectively. MEASURE: A PRECEDE instrument including predisposing, enabling, and reinforcing factors was employed to collect data. A Multivariate Analysis of Variance (MANOVA) and Multiple Regression Analysis were used to analyze the data. RESULTS: Smoking was reported by 39.8% of boys and 5.14% of girls. Students in the city of Shanghai had the best (against smoking) predisposing factors, but students in rural areas had the best (against smoking) enabling and reinforcing factors and consumed the fewest cigarettes. CONCLUSION: Results indicated that smoking behavior in students was affected strongly by enabling factors and reinforcing factors that were related to socioeconomic, cultural, and environmental influences in China.

Adolescent↗

Brachial endothelial function in subjects with familial combined hyperlipidemia and its relationships to carotid artery intima-media thickness.

AIM: The aim of this study was to quantify the flow-mediated dilatation (FMD) of brachial artery in asymptomatic members of families with familial combined hyperlipidemia (FCH) and to determine the relation between FMD and risk factors accompanying FCH. We also investigated the association between FMD and the intima-media thickness (IMT) of the common carotid artery. METHODS: Eighty-two members of 29 FCH families were divided into two groups: probands and hyperlipidemic first-degree relatives (HL) (n=47) and normolipidemic first-degree relatives (NL) (n=35). The control (C) groups, C-HL (n=20) and C-NL (n=20), consisted of sex- and age-matched healthy individuals. FMD was assessed in the brachial artery by measuring the change in brachial artery diameter in response to reactive hyperemia. RESULTS: Both hyperlipidemic subjects and their NL had significantly lower FMD (3.4+/-3% vs 6.3+/-2.8%, P<0.001, 5.2+/-2.3% vs 7.8+/-2.8%, P<0.01, respectively) compared to controls. In multivariate backward stepwise regression analysis, FMD in members of FCH families was independently associated with sex (P<0.001), age (P<0.01), C-peptide (P<0.05) and borderline with glycemia (P=0.052). FMD correlated inversely with IMT in all subjects of FCH families and in hyperlipidemic members. In multivariate backward stepwise regression analysis this relation remained independent (P<0.001, P<0.01, respectively). CONCLUSIONS: Members of FCH families showed impaired FMD, which was independently associated with markers of insulin resistance. FMD and IMT were independently associated in hyperlipidemic, but not in normolipidemic members of FCH families.

Adult↗

Lifestyle and behavioural risk factors associated with asthma morbidity in adults.

We studied the association between morbidity and personal lifestyle/behavioural factors that predispose to exposure to known environmental precipitants of asthma, in a group of asthmatics (n = 787) in primary-care clinics. Clinical severity of asthma was determined by questions regarding the frequency of daytime or nocturnal attacks, the number of visits to primary care or hospital emergency departments for treatment of acute attacks, and the number of hospitalizations, as well as the amount of sick leave in the past year. Questions concerning risk factors included ethnicity, clinical atopic status (current rhinitis/eczema), smoking, occupation, keeping of pets, rugs and carpets, use of brooms, burning of mosquito coils or incense, and outdoor air pollution, as well as the patient's knowledge of asthma care. The most significant independent predictors of asthma morbidity, identified from multivariate logistic regression analyses, were current keeping of either pets or rugs/carpets (OR 1.49; 95% CI 1.12-1.99), and current high-risk occupations (OR 0.59, 95% CI 0.40-0.89). A multiplicity of interacting factors and behavioural responses appear to influence the effects of allergens and other environmental precipitants on asthma morbidity in patients.

Adult↗

The impact of seeing physicians new to a patient on the response to screening reminders.

BACKGROUND: A large insurer in Hawaii mails annual reminders to its members regarding recommended health screenings. This study examined the associations between the characteristics of physicians visited after the reminders were sent and the health screenings received for breast, cervical, and colorectal cancers, and for diabetes and cholesterol. METHODS: The study population included members identified as needing health screenings from 2000 to 2003 based on age and gender criteria. The study used a longitudinal design focusing on the 12 months after reminders were sent. Data were analyzed using logistic regression examining physician visits, other health services, and receipt of health screenings by 1-month intervals subsequent to the reminder mailings. RESULTS: In adjusted, multivariable models, members who saw physicians they had not seen in the past year had odds ratios for obtaining health screenings 6 to 8 times higher than members who only saw previously visited physicians. This enhanced response occurred among members receiving their first, second, and third (or subsequent) annual reminder letter. The more physicians that were visited and who were new to the members, the more likely the members were to obtain health screenings. CONCLUSIONS: Members seeing physicians they had not seen in the past year had significantly higher screening rates than the members only seeing physicians they had previously visited. The results suggest that healthcare screening may receive less attention at repeat visits with a physician than at visits with a physician who is new to a member.

Adult↗

Personality factors and posttraumatic stress: associations in civilians one year after air attacks.

There is an ongoing debate on which risk factors for developing posttraumatic stress symptoms are more important--personality traits reflecting vulnerability, previous stressful experiences or characteristics of the traumatic event. In this study, posttraumatic stress symptoms and their relationship with personality traits, previous stressful experiences and exposure to stressful events during air attacks in Yugoslavia were investigated. The Millon Clinical Multiaxial Inventory (MCMI; Millon, 1983), Impact of Events Scale (IES; Horowitz, Wilner, & Alvarez, 1979), Life Stressor Checklist Revised (LSCL-R; Wolfe & Kimerling, 1997), and List of Stressors were administered to a homogeneous group of medical students 1 year after the attacks. In multiple regression analyses, compulsive and passive-aggressive personality traits and a higher level of exposure to stressors during air attacks independently predicted the degree of intrusion symptoms. Avoidance symptoms were predicted by avoidant personality traits and a higher exposure to stressors both previously in life and during the attacks. In the next step, we tested in analyses of variance whether personality traits, previous stressful experiences, and stressful events during attacks as independent variables interact in predicting intrusion and avoidance symptoms. For this, students were clustered into three groups depending on their predominant personality traits. In addition to direct predictive effects, there were significant interaction effects in predicting both intrusion and avoidance. The findings suggest that each of the tested factors, i.e., personality traits, previous stressful experiences, and exposure to traumatic events may have an independent and direct influence on developing posttraumatic stress. However, the effect of these factors cannot just be added up. Rather, the factors interact in their impact on posttraumatic stress symptoms. Bigger samples and longitudinal designs will be required to understand precisely how different personality traits influence response to stressful events.

Adaptation, Psychological↗

The analysis of repeated multivariate binary quality of life data: a hierarchical model approach.

Many quality of life measuring instruments consist of a number of questions that are answered on ordinal scales. Often these responses are then totalled to give a summary score for each quality of life domain within the instrument. This, however, may lose valuable information about individual aspects of patient quality of life and also can have little intuitive meaning. Here we present an alternative analysis, in which dichotomized individual items of the questionnaire are analyzed. We first show how a hierarchical logistic regression model for repeated binary data can be extended to the multivariate case. We then use such a model for analyzing the prevalence of six symptoms in a palliative treatment trial in non-small-cell lung cancer. The analysis provides information about the correlations between symptoms, both between and within person. If appropriate, it also permits the estimation of a treatment effect common to all symptoms. Methods for model checking are discussed. We conclude that this methodology can provide a more intuitive and informative analysis of quality of life data than that obtained by considering summary scores.

Carcinoma, Non-Small-Cell Lung↗

Obesity is a risk factor for reporting homebound status among community-dwelling older persons.

OBJECTIVE: To test the a priori hypothesis that obesity is a predictor of risk for reporting homebound status. RESEARCH METHODS AND PROCEDURES: A longitudinal cohort study was conducted with 21,645 community-dwelling men and women 65 to 97 years old. A nutrition risk screen was administered baseline between 1994 and 1999 and again 3 to 4 years later. Univariate analyses identified baseline variables associated with subsequent reporting of homebound status. Multivariable logistic regression models were created to identify baseline variables that were significant independent predictors of reporting homebound status. RESULTS: At baseline, 24% of the cohort had BMI > or = 30. There were 12,834 (45% men) respondents at follow-up (68% response). Non-responders at follow-up differed little from responders except for greater baseline age (72.2 +/- 6.2 vs. 71.4 +/- 5.6 years, p < 0.001) and reporting of any functional limitations (9.2% vs. 4.9%, p < 0.001). At follow-up, those who reported homebound status (n = 169) were significantly (p < 0.001) older (80.3 +/- 7.3 vs. 75.1 +/- 5.5 years) and more likely to report functional limitations (83.4% vs. 10.8%). Univariate analyses identified 16 baseline variables that were eliminated stepwise until five significant independent predictors remained: age > or = 75 years (2.21, 1.55 to 3.15/odds ratio, 95% confidence interval), BMI > or = 35 (1.75, 1.04 to 2.96), poor appetite (2.50, 1.29 to 4.86), low income (1.59, 1.00 to 2.56), and any functional limitation (10.67, 7.36 to 15.46). DISCUSSION: Obesity remained a significant independent predictor for reporting homebound status and should be considered in screening of older populations and in the planning, implementation, and evaluation of services for homebound older persons.

Aged↗

Exploratory analyses of caries data.

Some recent developments in statistical technique are applied to exploring published data of caries experience in 5-year old children. The methods are: robust regression and identification of outliers; analysis of compositional data derived from the dmf index; plotting compositional data using a ternary (or Ferrers) diagram, with a 96 per cent contour and principal axes; data-smoothing applied to 3-dimensional graphs of prevalence, severity and treatment response to caries. A strong relationship was found between prevalence and severity of caries, and 16 outlying observations were identified. The smoothed data demonstrated an insufficient treatment response to caries. The role of such analyses is discussed and recommendations made.

Child, Preschool↗

Dose and diameter relationships for facial, trigeminal, and acoustic neuropathies following acoustic neuroma radiosurgery.

PURPOSE AND OBJECTIVE: To define the relationships between dose and tumor diameter for the risks of developing trigeminal, facial, and acoustic neuropathies after acoustic neuroma radiosurgery, a large single-institution experience was analyzed. MATERIALS AND METHODS: Two hundred and thirty-eight patients with unilateral acoustic neuromas who underwent Gamma knife radiosurgery between 1987-1994 with 6-91 months of follow-up (median 30 months) were studied. Minimum tumor doses were 12-20 Gy (median 15 Gy). Transverse tumor diameter varied from 0.3-5.5 cm (median 2.1 cm). The relationships of dose and diameter to the development of cranial neuropathies were delineated by multivariate logistic regression. RESULTS: The development of post-radiosurgery neuropathies affecting cranial nerves V, VII, and VIII were correlated with minimum tumor dose and transverse tumor diameter (P < 0.01 for all except Dmin for VIII where P = 0.10). A comparison of the dose-diameter response curves showed the acoustic nerve to be the most sensitive to doses of 12-16 Gy and the facial nerve to be the least sensitive. CONCLUSION: The risks of developing trigeminal, facial, and acoustic neuropathies following acoustic neuroma radiosurgery can be predicted from the transverse tumor diameter and the minimum tumor dose using models constructed from data presently available.

Cranial Nerve Diseases↗

Impact of health insurance status on vaccination coverage in children 19-35 months old, United States, 1993-1996.

OBJECTIVES: To show how health insurance (privately and publicly insured, insured and uninsured) relates to vaccination coverage in children 19-35 months old, and how this can be used to better target public health interventions. METHODS: The National Health Interview Survey (NHIS) gathers information on the health and health care of the U.S. non-institutionalized population through household interviews. The authors combined immunization and health insurance supplements from the 1993 through 1996 NHIS, and classified children 19-35 months old by their immunization and insurance status. Results were compared using both bivariate and multivariate analyses, and the backwards stepwise selection method was used to build multivariate logistic regression models. RESULTS: Uninsured children tended to have lower vaccination coverage than those who had insurance, either private or public. Among those with insurance, publicly insured children had lower vaccination coverage than privately insured children. Backwards stepwise regression retained insurance status, metropolitan statistical area, and education of responsible adult family member as major predictors of immunization. Factors considered but not retained in the final model included child race/ethnicity, family poverty index, and region of country. CONCLUSIONS: Insurance status was a critical predictor of vaccination coverage for children ages 19-35 months. After controlling for confounders, the uninsured were about 24% less likely to receive all recommended shots than the insured and, among the insured, those with public insurance were about 24% less likely to receive all recommended vaccines than those with private insurance.

Black or African American↗

The microbiology of necrotizing soft tissue infections.

OBJECTIVE: A large number of necrotizing soft tissue infections (NSTI) treated at a single institution over an 8-year period were analyzed with respect to microbial pathogens recovered, treatment administered, and outcome. Based on this analysis, optimal empiric antibiotic coverage is proposed. METHODS: A retrospective chart review of all patients with documented NSTI was conducted. Microbiologic variables were tested for impact on outcome using Fisher's exact test and multivariate analysis by logistic regression. RESULTS: Review of the charts of 198 patients with documented NSTI revealed 182 patients with sufficient microbiologic information for analysis. These 182 patients grew an average of 4.4 microbes from original wound cultures, although a single pathogen was responsible in 28 patients. Eighty-five patients had combined aerobic and anaerobic growth, the most common organisms being, in order, Bacteroides species, aerobic streptococci, staphylococci, enterococci, Escherichia coli, and other gram-negative rods. Clostridial growth was common but did not affect mortality unless associated with pure clostridial myonecrosis. Mortality was affected by the presence of bacteremia, delayed or inadequate surgery, and degree of organ system dysfunction on admission. CONCLUSIONS: NSTI are frequently polymicrobial and initial antibiotic coverage with a broad-spectrum regimen is warranted. The initial regimen should include agents effective against aerobic gram-positive cocci, gram-negative rods, and a variety of anaerobes. The most common organisms not covered by initial therapy were enterococci. All wounds should be cultured at initial debridement, as changes in antibiotic coverage are frequent once isolates are recovered.

Algorithms↗

Validation of an overactive bladder awareness tool for use in primary care settings.

Overactive bladder (OAB)--a syndrome characterized by urinary urgency, with or without urge incontinence, urinary frequency and nocturia--is estimated to affect 10% to 20% of the US and European populations. This study was carried out to validate a patient-administered screening awareness tool to identify patients with bothersome OAB symptoms. Patients were recruited from 12 primary care and 1 gynecology practice during regularly scheduled appointments. Enrollees completed an 8-item questionnaire assessing the amount of "bother" they associated with OAB symptoms. Clinicians then asked the patients 4 questions regarding urinary frequency, urgency, nocturia, and incontinence. If the screening was positive for symptoms of OAB or if the patient provided positive responses to the urinary symptom questions, the clinician asked additional questions regarding lifestyle and coping behaviors. The clinician then diagnosed the patient, placing him or her in the "No OAB," "Possible OAB," or "Probable OAB" category. Multivariable logistic regressions controlling for age and sex were performed to assess the applicability of the tool for identifying patients with OAB. A total of 1,299 patients were enrolled, and 1,260 provided complete data. Patients were aged 51.6+/-17.0 years, 62% were female, most (89%) were Caucasian, 22% experienced urinary urgency, and 18% experienced urge incontinence. The prevalence of Probable OAB was 12%. The c-index of the model identifying patients with a diagnosis of Probable OAB was 0.96, with a sensitivity and specificity of 98.0 and 82.7. For OAB-V8 scores >or=8, the odds ratio for Probable OAB was 95.7 (95% CI: 29.3; 312.4). The OAB-V8 performed well in helping clinicians identify patients with bothersome OAB symptoms in a primary care setting and will assist clinicians in identifying patients who may benefit from treatment.

Female↗

Childhood adversities, parent-child relationships and dispositional optimism in adulthood.

BACKGROUND: Studies exploring the effects of childhood adversities and parent-child relationship on adulthood dispositional optimism are rather rare, have been performed on small, selected samples and lack analyses of interaction between childhood factors. METHOD: A total of 19970 working-aged Finns responded to the population-based HeSSup Study baseline questionnaire in 1998. The level of dispositional optimism (measured with the LOT-R scale) was analyzed according to self-reported childhood adversities, childhood parent-child relationships and their interaction, using multivariate linear regression analysis methods. A number of potential confounding factors (education, living alone, recent life events, somatic health and depressive mood) were taken into account. RESULTS: Childhood adversities were associated with decreasing optimism in a dose-response manner. Good parent-child relationships were associated with increasing optimism, with a partial buffering effect when confronting adversities. CONCLUSION: Those reporting childhood adversities and poor parent-child relationships had less optimistic expectations, which may need to be addressed in clinical settings.

Adult↗

Therapeutic efficacy of infliximab on active Crohn's disease under nutritional therapy.

OBJECTIVE: The aim of this investigation was to elucidate retrospectively the therapeutic effect of infliximab in patients with active Crohn's disease (CD) under nutritional therapy. MATERIAL AND METHODS: Using a review of the clinical records in 24 nationwide institutions specializing in inflammatory bowel disease, the short-term effect of infliximab in 97 patients with active CD was retrospectively investigated. The Crohn's disease activity index (CDAI) at baseline and after 2 weeks of a single infliximab administration (5 mg/kg) was compared among patients under total parenteral nutrition (TPN group, n=36), those following an elemental or polymeric diet (EN group, n=49) and those without TPN and EN (NN group, n=12). A decrease in CDAI >or= 70 or a CDAI value <150 at 2 weeks was regarded as effective. RESULTS: There was no difference in CDAI at baseline among the three groups. In each group, CDAI decreased significantly (from 250 (195-290) [median (interquartiles)] to 152 (123-233) in the TPN group, p<0.0001; from 259 (200-325) to 180 (130-238) in the EN group, p<0.0001; from 278 (222-291) to 164 (132-196) in the NN group, p=0.003). Infliximab was effective in 63.9% of patients in the TPN group, in 55.1% of those in the EN group and in 75% of the NN group. There was no statistical difference in efficacy among the three groups (p=0.4). Multivariate logistic regression analysis revealed younger age to be a significant factor related to the efficacy of infliximab. CONCLUSIONS: Infliximab is effective in patients with CD under TPN or EN. Age at infliximab administration may be predictive of response to infliximab.

Adolescent↗

Urinary 8-oxodeoxyguanosine, aflatoxin B1 exposure and hepatitis B virus infection and hepatocellular carcinoma in Taiwan.

To evaluate the role of oxidative stress and aflatoxin exposure on risk of hepatocellular carcinoma (HCC), a case-control study nested within a community-based cohort was conducted in Taiwan. Baseline urine samples, collected from a total of 74 HCC cases and 290 matched controls, were used to determine by enzyme-linked immunosorbent assays the level of urinary excretion of 8-oxodeoxyguanosine (8-oxodG), a biomarker of oxidative DNA damage and urinary aflatoxin B(1) metabolites, a biomarker of aflatoxin exposure. Multivariate-adjusted linear regression analysis showed that urinary aflatoxin metabolites and gender were significantly associated with level of urinary 8-oxodG among controls. Moreover, after adjustments for potential confounding factors, there was a statistically significant positive dose-response relationship between levels of urinary 8-oxodG and urinary aflatoxin metabolites (P < 0.0001). However, when compared with subjects in the lowest quartile of 8-oxodG, there was a decrease in risk of HCC, with adjusted odds ratios (ORs) of 0.8 [95% confidence interval (CI) 0.3-2.0], 0.7 (95% CI 0.3-2.0) and 0.7 (95% CI 0.2-1.7) for subjects in the second, third and fourth quartile, respectively. The combination of level of urinary 8-oxodG below the median and hepatitis B virus infection resulted in an OR of 11.4 (95% CI 3.9-33.3), compared with those with urinary 8-oxodG above the median and hepatitis B virus surface antigen negative. These results suggest that elevated levels of urinary 8-oxodG may be related to increasing level of aflatoxin exposure but may also indicate enhanced repair of oxidative DNA damage and therefore lower risk of HCC.

Adult↗

Therapy-resistant periodontitis. Psychosocial characteristics.

This study investigated the perspective of a stress system disorder in the pathogenesis of therapy-resistant periodontitis. The goal was to find indications that the stress-behaviour-immune system model holds as an explanatory model for the understanding of periodontal disease. 2 patient-groups were compared: one group classified as responding well to periodontal treatment (responsive-group, R-group, n=11); the other group was classified as responding less well to treatment (non-responsive-group, NR-group, n=11). Somatic and psychological factors were described as obtained by interviews and psychological testings. These findings were related to clinical data documented during the treatment of the patients. An exact logistic multivariate regression analysis was performed on a model based on variables selected by bivariate analysis (variable versus group). The results indicated that the NR-group patients displayed indications of more psychosocial strain and a more passive-dependent personality. The R-group patients displayed a more rigid personality and possibly a less stressful psychosocial situation in the past. The report highlights the possible contribution of stress factors in the context of therapy resistant periodontal disease, and the results seem to be understandable within the context of a stress system disorder perspective.

Adult↗