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Community-based study of hepatitis C virus infection and type 2 diabetes: an association affected by age and hepatitis severity status.

Past studies of the relation between hepatitis C virus (HCV) infection and type 2 diabetes conflict. The authors aimed to elucidate the relation by using a large community-based sample with a wide range of liver conditions. Between October 1997 and February 1998, 2,327 consecutive subjects (aged > or =35 years) were enrolled at the public health facility in Taiwan. Blood sugar, hepatitis B surface antigen, and antibody for HCV (anti-HCV) were tested. Abdominal sonography was performed on viral-hepatitis-positive subjects. In univariate analysis, older age, lower educational levels, sedentary work, body mass index of > or 25 kg/m2, and anti-HCV positivity were significantly associated with type 2 diabetes (p<0.05), but smoking, alcohol consumption, gender, and hepatitis B surface antigen status were not. In multivariate logistic regression, anti-HCV positivity was strongly associated with type 2 diabetes in subjects aged 35-49 years (odds ratio (OR)=3.3, 95% confidence interval (CI): 1.4, 8.0) and 50-64-years (OR=1.6, 95% CI: 1.1, 2.5). Sonographic evidence of fatty liver (OR=2.4, 95% CI: 1.2, 4.8) and chronic liver disease (OR=2.0, 95% CI: 1.0, 4.2) in anti-HCV-positive subjects was moderately associated with type 2 diabetes after age and gender adjustment. Data suggest that HCV infection is moderately associated with type 2 diabetes; the association was strongest for subjects aged 35-49 years and increased with severity of the liver condition.

Adult↗

The use of the Gompertz function to relate changes in life expectancy to the standardized mortality ratio.

BACKGROUND: Change in life expectancy may be more readily appreciated by a lay person as a measure of risk than the standardized mortality ratio (SMR). METHODS: The linear increase in the logarithm of the age-specific mortality rates with age (the Gompertz function) is used to deduce formulae connecting SMR with change in life expectancy. Their validity is checked by a comparison between the 1992 and 1952 mortality data for England and Wales, and between smokers and non-smokers in the American Cancer Society's second Cancer Prevention Study. RESULTS: It is shown that the Gompertz function is a good fit to mortality data for England and Wales from age 30 years upwards. Changes in life expectancy at ages 15, 25, 45 and 65 are presented for values of SMR from 0.5 to 3. A very simple formula connecting the two is valid at ages 15 and 25, and provides a reasonable approximation at age 45. CONCLUSIONS: The Gompertz relationship can be used to calculate the change in life expectancy corresponding to a particular SMR over a greater range than have previous methods, and, although subject to some uncertainties, can provide a quick method of judging the change in life expectancy that is associated with a given SMR value.

Adolescent↗

Attributable risk of exposures associated with sexually transmitted disease.

Attributable risk combines information on the prevalence of an exposure with a measure of the associated increment in risk, providing an estimate of the proportion of incident or prevalent disease that might be avoided by eliminating the exposure. Thus, attributable risk identifies exposures most productively targeted by public health interventions. Attributable risk can be defined as the ratio of average excess risk to average risk. As with other measures of association between exposure and disease computed from observational data, adjustment must be made for confounding factors. Estimates of attributable risk are highly variable. Nonetheless, attributable risk retains its usefulness as an approximate measure of the public health significance of exposures associated with acquisition of sexually transmitted disease, provided it is estimated and interpreted cautiously.

Female↗

Neoplastic and antineoplastic effects of beta-carotene on colorectal adenoma recurrence: results of a randomized trial.

BACKGROUND: In two large, randomized prevention trials, supplementation with beta-carotene increased the risk of lung cancer. Subjects in these studies were predominantly cigarette smokers, and the adverse effects were concentrated among those who also drank alcohol. Although beta-carotene supplementation appeared not to increase the risk of cancer generally, it is not clear if smoking and/or alcohol use alters the effect of beta-carotene on carcinogenesis at sites outside the lung. METHODS: We studied the effect of beta-carotene supplementation on colorectal adenoma recurrence among subjects in a multicenter double-blind, placebo-controlled clinical trial of antioxidants for the prevention of colorectal adenomas. A total of 864 subjects who had had an adenoma removed and were polyp-free were randomly assigned (in a factorial design) to receive beta-carotene (25 mg or placebo) and/or vitamins C and E in combination (1000 mg and 400 mg, respectively, or placebo), and were followed with colonoscopy for adenoma recurrence 1 year and 4 years after the qualifying endoscopy. A total of 707 subjects had two follow-up examinations and provided smoking and alcohol use data. Adjusted multivariate risk ratios (RRs) and 95% confidence intervals (CIs) were used to assess the effects of beta-carotene on adenoma recurrence. RESULTS: Among subjects who neither smoked cigarettes nor drank alcohol, beta-carotene was associated with a marked decrease in the risk of one or more recurrent adenomas (RR = 0.56, 95% CI = 0.35 to 0.89), but beta-carotene supplementation conferred a modest increase in the risk of recurrence among those who smoked (RR = 1.36, 95% CI = 0.70 to 2.62) or drank (RR = 1.13, 95% CI = 0.89 to 1.43). For participants who smoked cigarettes and also drank more than one alcoholic drink per day, beta-carotene doubled the risk of adenoma recurrence (RR = 2.07, 95% CI = 1.39 to 3.08; P for difference from nonsmoker/nondrinker RR <.001). CONCLUSION: Alcohol intake and cigarette smoking appear to modify the effect of beta-carotene supplementation on the risk of colorectal adenoma recurrence.

Adenoma↗

Recombinant human erythropoietin and overall survival in cancer patients: results of a comprehensive meta-analysis.

BACKGROUND: Anemia associated with cancer and cancer therapy is an important clinical and economic factor in the treatment of malignant diseases. METHODS: We conducted a systematic literature review to assess the efficacy of erythropoietin to prevent or treat anemia in cancer patients with regard to red blood cell transfusions, hematologic response, adverse events, and overall survival. We searched the Cochrane Library, Medline, EMBASE, and other databases for relevant articles published from January 1985 to December 2001. We included all randomized controlled trials that compared the use of recombinant human erythropoietin (plus transfusion, if needed) with no erythropoietin treatment (plus transfusion, if needed). Relative risks (RRs) and 95% confidence intervals (CIs) were calculated under a fixed-effects model. Clinical and statistical heterogeneity were examined with sensitivity analyses and meta-regression. Statistical tests for effect estimates were two-sided. RESULTS: We identified 27 trials involving 3287 adult patients. Patients treated with erythropoietin had a lower relative risk of having a blood transfusion than untreated patients (RR = 0.67, 95% CI = 0.62 to 0.73). Erythropoietin-treated patients with baseline hemoglobin levels lower than 10 g/dL were more likely to have a hematologic response than untreated patients (RR = 3.60, 95% CI = 3.07 to 4.23). The relative risk for thromboembolic complications after erythropoietin treatment was not statistically significantly increased (RR = 1.58, 95% CI = 0.94 to 2.66) compared with that of untreated patients. There is suggestive but inconclusive evidence that erythropoietin may improve overall survival (adjusted data: hazard ratio [HR] = 0.81, 95% CI = 0.67 to 0.99; unadjusted data: HR = 0.84, 95% CI = 0.69 to 1.02). CONCLUSIONS: Erythropoietin treatment may reduce the risk for blood transfusions and improve hematologic response in cancer patients. However, our favorable survival outcome is in contrast to two large (N = 351 and 939) recently published randomized controlled trials in which erythropoietin-treated patients had statistically significantly worse survival than untreated patients. Possible reasons for the disparity with our results include differences in study population and design, higher target hemoglobin levels and higher risk of thromboembolic complications, and concerns that erythropoietin may stimulate tumor growth.

Anemia↗

Body fat distribution and osteoarthritis.

The association of body fat distribution with single and combined site osteoarthritis was investigated using data from the US Health Examination Survey I, 1960-1962 (HES I) and the first National Health and Nutrition Examination Survey I, 1971-1975 (NHANES I). The study included 1,636 adults aged 35-79 years from HES I with hands and feet radiographs and four anthropometric fat distribution measures--subscapular and triceps skinfolds, waist girth, and seat breadth--and 3,885 adults aged 45-74 from NHANES I with knee radiographs and subscapular and triceps skinfold measures. Sex-specific data, adjusted for age, race, and body mass index, were analyzed using polychotomous logistic regression. There was a positive association of body mass index with knee osteoarthritis and with combined hands and feet osteoarthritis. A peripheral body girth pattern was associated with combined site osteoarthritis of the hands and feet; however, there was no consistent pattern of association of body fat distribution with knee osteoarthritis nor with osteoarthritis of the hands or feet only. These findings suggest that the central body fat pattern observed in previous studies to be associated with cardiovascular and gallbladder disease, and with diabetes, is not associated with osteoarthritis of the hands, feet, or knees.

Adipose Tissue↗

Historical assessment of some specific methods for projecting the AIDS epidemic.

Extrapolation and back-calculation methods for predicting future acquired immunodeficiency syndrome (AIDS) incidence are assessed by examining how they would have performed at various points in the past. The methods use monthly AIDS diagnosis counts through December 1991 for all adults and adolescents in the United States to predict diagnoses 1-3 years into the future. When used on seasonally adjusted data, the average errors in projections by the different methods are smaller than the possible errors due to uncertainty in AIDS counts. This suggests that measuring and improving the completeness of AIDS surveillance may have more potential to improve projections than methodological enhancements.

Acquired Immunodeficiency Syndrome↗

Reference values for pulsed Doppler signals from the blood flow on both sides of the aortic valve.

Pulsed Doppler signals were recorded in 215 healthy subjects, 120 males and 95 females, between 1 and 65 years of age. The measurements were performed in the left ventricular outflow tract (LVOT) and in the ascending aorta (AAO). Amplitude spectra from the Doppler signals were stored in digital form together with adjustment data for the instrument, the simultaneously registered ECG and respiration signal. The maximum velocity (Vmax), the maximum acceleration (Amax) and the width of the velocity distribution around Vmax (width) were derived from these spectra and used for the characterization of the signals. These parameters were computed without observer interaction using a computer program. Effects of age, sex, body surface area, heart rate and respiration were studied. Reference ranges were calculated. The following conclusions can be drawn: Vmax and Amax in the AAO decrease clearly with increasing age from approximately 100 to 60 cm s-1 and from 2000 to 1000 cm s-2 (medians), respectively. The variation of the width in the AAO is greater for people over 45 years. Vmax, Amax and width in the LVOT increase slightly with advancing age from approximately 60 to 80 cm s-1, 800 to 1000 cm s-2 and 12 to 15 cm s-1 (medians), respectively. These parameters of flow were either unrelated or only weakly related to other physiological variables in this study group.

Adolescent↗

Reference values for pulsed Doppler signals from the blood flow velocity on both sides of the pulmonary valve.

Pulsed Doppler signals were recorded from the pulmonary artery and the right ventricular outflow tract in 215 healthy subjects (120 males, 95 females; 1-65 years). Amplitude spectra from these Doppler signals were stored in digital form together with adjustment data for the instrument and the simultaneously recorded ECG. From these Doppler spectra the median of the maximal velocity (Vmax), the maximal acceleration (Amax) and the dispersion of the velocity distribution around Vmax (width) were calculated. These three median values were used to characterize the Doppler spectra and to define normal values for bloodflow velocities. Thus, calculations were made without observer interacting using a well-defined computer program. The effect of age, gender, body surface area and heart rate were studied. Reference ranges were calculated. There is a slight decrease of the median value of Vmax and Amax in the pulmonary artery during lifetime from 80 to 70 cm s-1 and from 1,200 to 800 cm s-2, respectively. On the other hand, there is no correlation between age and Vmax and Amax in the right ventricular outflow tract. The width of the spectra increases with age at both sites. No significant changes with age were seen with the other variables.

Adolescent↗

Association of twelve immune-related genes with performance of three broiler lines in two different hygiene environments.

Elite populations of farm animals under genetic selection are often maintained in high hygiene conditions, yet the commercial populations may be raised in, and are expected to perform well in, environments of varied hygiene levels. This presents special challenges to genetically improve those traits for which genotype by environment interactions are important. Twelve immune-related genes were studied for associations with general mortality and other performance traits in 3 elite commercial broiler chicken lines raised in high and low hygiene environments. The genes were toll-like receptor 4, MD-2 (accessory' protein of TLR4), interferon-gamma, transforming growth factor-beta3, inducible nitric oxide synthase, macrophage migration inhibitory factor, interleukin-2, caspase-1, inhibitor of apoptosis protein-1, tumor necrosis factor-related apoptosis-inducing ligand, chicken B-cell marker, and bone morphogenetic protein-7. From a total of 56 identified single-nucleotide polymorphisms (SNP) in 12 genes, 14 SNP that had moderate allelic frequencies in at least 2 of the 3 lines were typed in about 100 progeny-tested sires from each of 3 elite commercial broiler chicken lines using restriction fragment length polymorphism techniques and then used in association analysis. The traits measured on the progeny (total progeny = 145,467) were: mortality from hatching to 14 d and from 14 to 40 d of age, BW at 7 and 40 d of age, feed conversion, ultrasound breast depth, percentage of breast, eviscerated carcass weight, twisted legs or evident tibial dyschondroplasia, x-ray-inspection-based subclinical or incipient development of tibial dyschondroplasia, curly or crooked toes or bowed legs, oxygen content of blood, and female's antibody titer to infectious bursal disease virus at 27 wk. Association analyses were conducted with allele and haplotype substitution effect models using progeny mean data adjusted for fixed and mate effects as sire trait records. Ten of the 12 genes had SNP associations with at least 1 trait. Most detected effects were with mortality and growth traits. Most gene-SNP trait associations varied by genetic line or with environment. These results indicate that associations of candidate genes with important broiler traits can be identified in multiple environments, and they offer a potential for the implementation of marker-assisted selection for traits expressed in the environment in which the commercial broiler needs to perform. The effects of these immune-related candidate genes, however, are complex and affected by genetic background and environment.

Animal Husbandry↗

Pooling two controlled comparisons of milnacipran (F2207) and amitriptyline in endogenous inpatients. A new approach in dose ranging studies.

Milnacipran is a new potential antidepressant selected for its equipotent inhibition of noradrenaline and serotonin uptake and its lack of effect at any postsynaptic receptor. We recently compared milnacipran 100 and 50 mg/d and amitriptyline 150 mg/d in three parallel randomized groups of major depressive inpatients and found a statistically significant superiority of milnacipran 100 mg/d and amitriptyline over milnacipran 50 mg/d after 4 weeks of treatment. Later on we found similar improvement with milnacipran 200 mg and amitriptyline 150 mg but better tolerance with milnacipran. In order to compare the therapeutic activity of the three doses of milnacipran (50 mg/d, 100 mg/d, and 200 mg/d) we used the responses to amitriptyline as a reference against which to compare the 3 doses of the new drug using analysis of variance on the adjusted data. This approach reveals milnacipran 200 mg is more effective than milnacipran 50 and 100 mg and is the only dose which shows efficacy at least equivalent to that of amitriptyline 150 mg. The dose/efficacy relationship was linear.

Amitriptyline↗

Use of hospital services under two prepaid plans.

This study compares the use of hospital services under two prepaid plans offered to Stanford University employees and their families. One is a Kaiser plan while under the other (Clinic plan), physician services are provided by the Palo Alto Medical Clinic, a multispecialty, largely fee-for-service group practice, and hospital services are covered by a Blue Cross policy. Using age- and sex-adjusted data, the hospital admission rate excluding deliveries is higher under the Clinic plan (44.2 admissions per 1,000 personyears compared with 38.2 under the Kaiser plan), but hospital days per 1,000 personyears are almost identical (249.8 days under the Kaiser plan, 250.7 under the Clinic plan). The difference in the admission rates is due to the higher surgical admission rate under the Clinic plan (32.4 admissions per 1,000 personyears compared to 25.0 under the Kaiser plan). However, when surgical procedures performed in the hospital on a nonadmission basis are added to surgical admissions, the surgical rates under the two plans become very close (35.7 admissions and procedures per 1,000 personyears under the Kaiser plan and 37.6 under the Clinic plan). This lends some support to the hypothesis that the lower hospital surgery rates found under prepaid group practice plans may be due as much to the group practice form of their organization as to their prepaid feature. The authors offer some possible reasons why surgeons in fee-for-service group practices may have relatively low surgery rates even though they do not have the incentive to hold down costs which surgeons in prepaid group practices have.

Ambulatory Surgical Procedures↗

Use of ambulatory medical care by the poor: another look at equity.

Access to health services by the poor and other disadvantaged groups has improved considerably over the past 15 years. These circumstances have led some to question whether the poor now have equal access to health care. This article presents recent evidence from the 1976-78 National Health Interview Surveys (NHIS) comparing utilization among age, race, and income groups. Without adjustment for health status, the poor have more physician visits than those with higher incomes. After adjusting for age and health status, however, these differences are reversed. Depending on which measure is used, the poor have between 7 per cent and 44 per cent fewer visits than those with income above twice the poverty level. Furthermore, the age- and health-adjusted data show blacks have significantly fewer visits than their white counterparts. In addition, there are large differences among race and income groups in the characteristics of the ambulatory care obtained. Blacks and the poor are much more likely to use hospital clinics and less likely to use private physician offices or telephone consultations. The poor also receive less preventive care. It would appear from the present evidence that still further progress is required to achieve the goal of equity in the distribution of medical care services.

Adolescent↗

Chronic disease and health system performance. Care of osteoarthritis across three health services.

Care of patients with osteoarthritis is compared for three different types of health service: fee-for-service, prepayment (Kaiser Health Plan), and an experimental service (Midpeninsula Health Service--MHS). While charging fees-for-service, MHS modifies medical practice in defined ways and seeks to involve patients through supervised self-care. Volunteer panels of patients provide the data at 6-month intervals through self-administered questionnaires. This report covers the first 18 months. Health status has not changed. Annualized utilization data, adjusted for age, income, education, pain, disability, disease duration, and prescription drug use, indicate that MHS members have fewer physician visits, fewer diagnostic tests, and lower antiinflammatory drug use than the other two services. MHS members express satisfaction equal to or greater than other participants. The results suggest that, in addition to modified financial incentives, there is another strategy that is relevant to achieving effective, efficient, and satisfying health care.

Aged↗

The health status of women following cosmetic surgery.

A retrospective study was performed to determine the frequency of new symptoms and diseases after silicone breast implantation. Questionnaires were mailed to 826 women who made up a breast implant group (n = 516) and a control group who had undergone blepharoplasty (n = 124), liposuction (n = 111), or rhinoplasty (n = 75). Responses were obtained from 370 women (45 percent); however, 68 of these patients (18 percent) were considered ineligible. The overall response rate was 59 percent for the breast implant group and 46 percent for controls. The 302 eligible women included patients with silicone breast implants (n = 222) and controls (n = 80). Women with implants were significantly younger than controls, the median age of women with breast implants being 37 years compared with 46.5 years for controls (p < 0.0001). We compared the incidence of 23 symptoms and 4 connective-tissue diseases after cosmetic surgery in the two groups. The symptoms of swollen glands under arms (p < 0.05) and tender glands under arms (p < 0.01) were statistically more frequent in the breast implant group. The symptom change in skin color was more common in the controls (p < 0.001). The Bonferroni correction for multiple (27) endpoints adjusts the 5 and 1 percent significance cutoff points to 0.00185 and 0.00037, respectively, leaving only change of skin color significant at the 5 percent level on the adjusted data. No cases of scleroderma or lupus were found, and the incidence of arthritis was not significantly different between the implant and control groups.

Adult↗

Association between coffee consumption and markers of inflammation and cardiovascular function during mental stress.

BACKGROUND: Coffee is widely consumed in the Western diet and therefore has important implications for public health. Research findings pertaining to the effects of coffee consumption on cardiovascular health are conflicting, and the role of caffeine is not clear. OBJECTIVE: To examine the relationship between coffee intake, inflammation and cardiovascular function at baseline and during mental stress, both cross-sectionally and after a 4-week period of withdrawal of coffee during which intake of caffeine was maintained. METHODS: Eighty-five healthy, non-smoking men with varying coffee-drinking habits were recruited. Blood pressure, heart rate, and markers of inflammation [C-reactive protein (CRP), von Willebrand factor antigen (vWF)], were measured at baseline and during mental stress. These measures were repeated after a 4-week period of withdrawal of coffee, during which intake of caffeine was maintained. Habitual levels of coffee and caffeine consumption were assessed from a self-reported questionnaire, and saliva samples for the analysis of caffeine concentrations were collected regularly throughout the period of withdrawal, to confirm compliance. RESULTS: Multiple linear regression analysis of pre-withdrawal data, adjusted for age, body mass index and intake of tea, red wine, fruit, vegetables, oily fish and dietary supplements revealed that coffee consumption was positively related to baseline systolic blood pressure, and increased heart rate and vWF responses to mental stress. Four weeks after withdrawal of coffee, the heightened vWF and heart rate responses to stress in habitual coffee drinkers persisted, whereas baseline systolic blood pressure had decreased. Total caffeine intake was unrelated to any measures of physiological function. CONCLUSIONS: Habitual coffee consumption is associated with heightened acute vascular inflammatory responses to mental stress, although these effects are not affected by short-term abstinence from coffee. These findings suggest that the relationship between coffee and markers of cardiovascular risk may be explained by residual or unmeasured confounding factors.

Adult↗

Preoperative antibiotics and mortality in the elderly.

OBJECTIVE AND BACKGROUND: It is generally thought that the use of preoperative antibiotics reduces the risk of postoperative infection, yet few studies have described the association between preoperative antibiotics and the risk of dying. The objective of this study was to determine whether preoperative antibiotics are associated with a reduced risk of death. METHODS: We performed a multivariate matched, population-based, case-control study of death following surgery on 1362 Pennsylvania Medicare patients between 65 and 85 years of age undergoing general and orthopedic surgery. Cases (681 deaths within 60 days from hospital admission) were randomly selected throughout Pennsylvania using claims from 1995 and 1996. Models were developed to scan Medicare claims, looking for controls who did not die and who were the closest matches to the previously selected cases based on preoperative characteristics. Cases and their controls were identified, and charts were abstracted to define antibiotic use and obtain baseline severity adjustment data. RESULTS: For general surgery, the odds of dying within 60 days were less than half in those treated with preoperative antibiotics within 2 hours of incision as compared with those without such treatment: (odds ratio = 0.44; 95% confidence interval, 0.32-0.60), P < 0.0001). For orthopedic surgery, no significant mortality reduction was observed (OR = 0.85; 95% confidence interval, 0.54-1.32; P < 0.464). INTERPRETATION: Preoperative antibiotics are associated with a substantially lower 60-day mortality rate in elderly patients undergoing general surgery. In patients who appear to be comparable, the risk of death was half as large among those who received preoperative antibiotics.

Age Factors↗