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PubMed2002

Impact of multiple HPV infection on response to treatment and survival in patients receiving radical radiotherapy for cervical cancer.

To obtain information on the incidence and the clinical significance of infection with various types of the human papillomavirus (HPV) in cancer of the uterine cervix, we retrospectively examined the HPV status of 106 patients who had received radical radiotherapy for cervical cancer stages IB to IIIB. DNA was extracted from formalin-fixed, paraffin-embedded biopsies and PCR was carried out to identify HPV types 16, 18, 31, 35, 33 and 45. To detect additional HPV types, consensus PCR products were cloned and sequenced. A catalyzed signal-amplified colorimetric in situ hybridization was carried out in 84 of 106 specimens as a positive control. Response to therapy, progression-free survival (PFS) and cervical cancer-specific survival (CCSS) were the statistical endpoints. Survival analysis was carried out using univariate and multivariate analysis (Cox regression). Ninety-six patients (90.6%) were HPV-positive and 42/96 (43.7%) were positive for multiple HPV types. Eight patients had persistent disease after radiotherapy. From these 8 patients, 7 were infected with multiple HPV types and only 1 patient had an infection with a single HPV type. After a median follow up period of 50 months, patients with multiple HPV infection had a significantly shorter PFS and CCSS compared to those with single HPV infection (24.8% and 34.9% vs. 64% and 60.8%, Log rank, p < 0.01 and 0.04). In multivariate analysis, the presence of multiple HPV types (RR 1.9), node status (RR 2.3), tumor size (RR 3.2) and histologic type (RR 4.8) were independent prognostic factors of CCSS. Our results demonstrate that the presence of multiple HPV types is associated with poor response and with reduced survival in cervical cancer patients who receive radiotherapy as the primary treatment.

Adenocarcinoma↗
PubMed1990

Alternatives for using multivariate regression to adjust prospective payment rates.

Multivariate regression analysis has been used in structuring three of the adjustments to Medicare's prospective payment rates. Because the indirect-teaching adjustment, the disproportionate-share adjustment, and the adjustment for large cities are responsible for distributing approximately $3 billion in payments each year, the specification of regression models for these adjustments is of critical importance. In this article, the application of regression for adjusting Medicare's prospective rates is discussed, and the implications that differing specifications could have for these adjustments are demonstrated.

Hospitals, Rural↗
PubMed2004

Snoring and atopic disease: a strong association.

The prevalence and factors associated with snoring and habitual snoring in Asian children are largely unknown. Our objectives were to evaluate the prevalence and factors associated with snoring and habitual snoring in preschool and primary school children in Singapore. A self-response questionnaire on snoring was administered to parents of children aged 4-7 years in randomly selected preschools and primary schools in Singapore. The overall response rate was 91.3% (nt = 11,114). Snoring and habitual snoring were reported in 28.1% and in 6.0% of the children, respectively. On multivariate logistic regression analysis, snoring was significantly associated with male gender, race, atopy (asthma, allergic rhinitis, or atopic dermatitis), maternal atopy (allergic rhinitis or atopic dermatitis), maternal smoking, and breastfeeding. Habitual snoring was significantly associated with obesity (odds ratio (OR), 3.75; 95% confidence interval (CI), 1.67-8.42), allergic rhinitis (OR, 2.90; 95% CI, 2.06-4.08), atopic dermatitis (OR, 1.80; 95% CI, 1.28-2.54), maternal smoking (OR, 2.22; 95% CI, 1.09-4.53), and breastfeeding (OR, 1.49; 95% CI, 1.11-1.98). Atopy was the strongest risk factor for habitual snoring, and the effect was cumulative. The odds ratio of a child with all three atopic diseases (asthma, allergic rhinitis, and atopic dermatitis) to have habitual snoring was 7.45 (95% CI, 3.48-15.97). In conclusion, snoring and habitual snoring are common in Asian children. Atopy is strongly associated with snoring and habitual snoring. We suggest that children who are significantly atopic receive additional attention during screening for snoring, habitual snoring, and other features of obstructive sleep apnea syndrome.

Child↗
PubMed1992

The use of cusums and other techniques in modelling continuous covariates in logistic regression.

The assessment of continuous covariates singly as possible predictors in a multivariable logistic regression model is an important first step in the analysis. An approach to plotting which uses a cusum (cumulative sum) of the binary response variable is described. Extreme-deviation statistics associated with the cusum may be used to detect monotonic and non-monotonic trends. Probability plots of the covariate in the two groups defined by the response variable may help to determine the appropriate scale (transformation) of the covariate and to anticipate possible problems with the logistic fit. The ratio of the variances in the response/non-response groups is informative about the need for a quadratic term in the logistic model. Smoothed scatterplots of the response are valuable in displaying the observed and fitted values. The techniques are illustrated with two data sets.

Binomial Distribution↗
PubMed2004

Use of erythropoietin in cancer patients: assessment of oncologists' practice patterns in the United States and other countries.

PURPOSE: To assess physician use of erythropoietin in cancer patients before publication of the American Society of Clinical Oncology/American Society of Hematology guidelines. METHODS: Questionnaires about erythropoietin use in practice and 12 hypothetical clinical scenarios involving patients with cancer were mailed to 2000 oncologists/hematologists in the United States and 19 other countries. Response rates were 30% in the United States and 25% internationally. Data on erythropoietin use for ovarian cancer were obtained from one clinical trial. Multivariate regression models assessed predictors of erythropoietin prescription. RESULTS: Most physicians selected a hemoglobin level < or =10 g/dL as an upper threshold for erythropoietin use (36% to 51% of U.S. physicians and 21% to 32% of foreign physicians). Frequent erythropoietin use (defined as use in at least 10% of cancer patients) was higher in the United States than elsewhere (adjusted odds ratio [OR] = 5.8; 95% confidence interval [CI]: 2.5 to 13.4). Among U.S. physicians, those who said they used erythropoietin frequently were more likely to be in fee-for-service than managed care settings (OR = 2.2; 95% CI: 1.3 to 3.7). Those who reported never using erythropoietin practiced in countries that had lower annual per capita health care expenditures, lower proportions of privately funded health care, and a national health service (P <0.05 for all comparisons). Of 235 ovarian cancer patients who received topotecan, 38% (45/118) of U.S. patients and 2% (2/117) of European patients who developed grade 1 anemia (hemoglobin level between 10 and 12 g/dL) were treated with erythropoietin (P <0.01). CONCLUSION: Financial considerations and a hemoglobin level <10 g/dL appear to influence erythropoietin use in the United States, whereas financial considerations alone determine erythropoietin use abroad.

Anemia↗
PubMedDate not supplied

[Associations between bioaerosols coming from livestock facilities and asthmatic symptoms in children].

Although health effects of occupational exposures to livestock emissions are known, potential associations between living in the neighbourhood of intensive livestock facilities and the risk of developing respiratory or allergic diseases are still under discussion. During routine school entry examinations in selected rural districts in Lower Saxony we asked parents about respiratory and allergic symptoms of their 5-6 year old children. A questionnaire with standardised questions of the ISAAC-Studies for respiratory and allergic symptoms and corresponding risk factors was used. Complementarily the children were examined for visible signs of flexural dermatitis and in a subsample the SX1-test was used as an in vitro test for inhalative IgE mediated sensibilisations in capillary blood. Individual exposure to bioaerosols (endotoxin, fungi, bacteria and total dust) coming from livestock facilities was estimated using a Lagrange dispersion model based on the emission rates and locations of the lifestock facilities. A total of 7943 questionnaires (response rate over 85%) were analysed, of which 3867 could be used for the correlation analyses between exposition to endotoxin and asthmatic symptoms. Multivariate logistic regression models were analyzed, considering an atopic disease of the parents as a potential effect modifier and not as a confounder. The prevalence of allergic and asthmatic symptoms is similar to the results of other comparable studies, e. g. "wheezing in the last 12 months" 15.9% for boys and 12.9% for girls. An increase in the prevalence of asthmatic symptoms for higher endotoxin levels was observed only for children of atopic parents. The multivariate controlled odds ratio for one unit logarithm endotoxin concentrations is 1.15, p-value 0.016. Similar effects were observed for other asthma indicators, but not for subjective criteria of the exposition, e. g. the distance to the next large livestock facility guesstimated by parents. Among the overall analysed potential associations between exposition to bioaerosols and asthmatic and allergic symptoms only a few were statistically significant. The discussed association between endotoxin and asthmatic symptoms in predisposed children needs further investigation.

Age Factors↗
PubMed2000

What terminally ill patients care about: toward a validated construct of patients' perspectives.

BACKGROUND: Citizens have conveyed to professionals that care at the end of life is less than optimal. Efforts to improve matters have tended to work in piecemeal fashion, on tangible more than personal aspects of care, and without the benefit of documented perspectives of those who face dying. Policy initiatives and clinical interventions need guidance from a broad framework that is validated by patients' perspectives. PURPOSE: Our goals were to: (1) assess the construct validity and stability over time of the portions of a conceptual framework that concern patients' subjective experiences; (2) develop a foundation for measurement of these personally meaningful factors; and (3) examine these factors' associations for potential clinical or policy significance. POPULATION: Patients were from six diverse geographical areas whose physicians judged their survival prognosis to be 6 months or less. Physicians who referred the patients were randomly selected from state and specialty association lists. METHODS: We used in-person survey methodology and multivariate analysis of patient responses. The analysis fell into two parts. Using exploratory factor analysis, we looked for evidence of discrete dimensions of experiences. Using regression analysis, we examined associations among them. RESULTS: Of 1,131 eligible patients, 988 were interviewed (87.4% response rate). Of 682 patients who survived to follow-up interview 4-6 months later, 650 were interviewed (95.3% response rate). Exploratory factor analysis identified 12 discrete factors (accounting for 55% of variance; maximum Spearman's p = 0.24), 8 of which met criteria for representing measurable dimensions (accounting for 46% of variance). These 8 were: patient-clinician relationship; social connectedness; caregiving needs; psychological distress; spirituality/religiousness; personal acceptance; sense of purpose; and clinician communication. Eigenvalues ranged from 1.45 to 6.30 and Cronbach's alpha from 0.63 to 0.85. The concordance between these dimensions and those in the proposed framework indicated that two dimensions required minor modifications and six were confirmed, providing evidence of good construct validity for this portion of the framework. The same dimensions were also evident at follow-up except that the first two above-listed loaded on one combined factor, clinician interaction (eigenvalues 1.83-7.92; Cronbach's alpha from 0.64 to 0.86). This provides evidence of the construct's stability over time. Clinical communication and patient-clinician relationship were associated (odds ratio [OR] 2.79, 2.31-3.36). Better clinician communication correlated with somewhat better personal acceptance (OR 1.10,1.02-1.19), and a better patient-clinician relationship correlated with less psychological distress (OR 0.84, 0.75-0.95). CONCLUSIONS: We conclude that: (1) Personally meaningful aspects of patients' experience of terminal illness can be represented in valid, multidimensional constructs that are stable over time; (2) They are measurable; and (3) Aspects of the therapeutic relationship appear to correlate with patients' experience of the dying process.

Journal Article↗
PubMed2002

VA community-based outpatient clinics: performance measures based on patient perceptions of care.

BACKGROUND: The Department of Veterans Affairs (VA) recently initiated a system of Community- Based Outpatient Clinics (CBOCs) to enhance delivery of primary care to veterans. OBJECTIVE: The objective of this study was to determine the effect of CBOCs on patients' perceptions of care. RESEARCH DESIGN: The study design is a cross-sectional survey. SUBJECTS: This study compares 4,980 patients from 44 geographically diverse CBOCs to 4,159 patients from 36 parent VA Medical Center primary care clinics administratively and geographically associated with the CBOCs studied. MEASURES: Survey data were obtained from the 1998 VA National Outpatient Customer Satisfaction Survey which assesses eight multiitem scales addressing access and timeliness of care, education/information, patient preferences, emotional support, coordination of care, courtesy, and specialty care access. Each scale was evaluated based upon item responses that indicate a problem with care. The survey also contained SF-12 health status measures used for case-mix adjustment. RESULTS: Multivariate logistic regression controlling for patient health status measures revealed that CBOC patients reported fewer problems with care than VA-based patients on 7 of 8 scales though the absolute differences were small for most of the scales. The largest difference was observed for the access/timeliness scale. Significant differences between VA-staff and contract CBOCs were not observed. CONCLUSIONS: These results suggest that veterans participating in VA's initiative to provide primary care in community-based settings report no more than, and in some dimensions fewer problems with care compared with veterans who receive care in VAMC clinics.

Aged↗
PubMed2005

Racial and ethnic disparities and perceptions of health care: does health plan type matter?

OBJECTIVE: To examine whether racial and ethnic differences in the distribution of individuals across types of health plans explain differences in satisfaction and trust with their physicians. DATA SOURCES: Data were derived from the 1998-1999 Community Tracking Household and Followback Studies and consisted of a nationwide sample of adults (18 years and older). DATA COLLECTION: The data were collected by telephone survey. Surveys were administered in English and Spanish. The response rate for the Household Survey was 63 percent, and the match rate for the Followback Survey was 59 percent. STUDY DESIGN: Multivariate analyses used regression methods to detect independent effects of respondent race and ethnicity on satisfaction and trust with physician, while controlling for enrollment in different types of health plans. PRINCIPAL FINDINGS: Racial and ethnic minorities are more likely than whites to have lower levels of trust and satisfaction with their physician. The most prominent differences occurred within the Latino and Native American/Asian American/Pacific Islander/Other ("Other") populations. Plan type does not mitigate the relationship between race/ethnicity and trust and satisfaction for the overall adult population. CONCLUSIONS: Disparate levels of trust and satisfaction exist within ethnic and minority populations, even when controlling for the distribution of individuals across types of health plans. The results demonstrate a need to better understand the health care-related factors that drive disparate trust and satisfaction.

Adult↗
PubMed2001

A prospective study of work related factors and physical exercise as predictors of shoulder pain.

OBJECTIVES: To evaluate the effects of work related and individual factors as well as physical activity and sports on the incidence and persistence of shoulder pain among forestry workers. METHODS: Workers in a large Finnish forestry company replied to a questionnaire (a modified version of the Nordic questionnaire) on musculoskeletal pain and its possible risk factors for 4 consecutive years 1992-5. This 1 year follow up study covers the time 1994-5. Year 1994 was chosen as baseline because in that year the questionnaire contained for the first time more detailed questions about different sports. The response rate in 1995 was 90%. The effects of the predictors on 1 year incidence and persistence of shoulder pain were studied with multivariate logistic regression modelling. RESULTS: At baseline, 2094 subjects had been free of shoulder pain during the preceding 12 months. After 1 year, 14% (n=285) reported having mild or severe shoulder pain. Higher age, obesity, and mental stress as well as physically strenuous work and working with trunk forward flexed or with a hand above shoulder level increased the risk of incident shoulder pain. Of the different sports activities, dancing increased the risk of incident pain whereas jogging decreased the risk significantly. Of those 419 workers who had severe shoulder pain at baseline, 55% (n=230) still had severe pain 1 year later. Higher age, overload at work, and working with a hand above shoulder level increased the risk of persistent severe shoulder pain whereas cross country skiing and general sports activity decreased the risk. CONCLUSION: Our results support the current view that shoulder pain is the result of many factors, including occupational and individual factors. In this longitudinal study, physical work with a heavy load, awkward work postures, mental stress, and obesity were the risk factors at which preventive measures could be aimed. As a new finding, physical exercise had more protective than impairing effects on the shoulders.

Adult↗
PubMedDate not supplied

Ambient air quality and occurrence of multiple sclerosis relapse.

Infectious viruses and bacteria can trigger multiple sclerosis (MS) exacerbations. Seasonally changing concentrations of ambient air pollutants are known to predispose to transmissible infections, to induce systemic immune responses and to enhance existing peripheral inflammation. Ambient air quality and monthly MS relapse occurrence in south-western Finland were compared by multivariate logistic regression. The odds ratio of the risk of a relapse onset was over fourfold (4.143, p < 0.001) when the concentration of inhalable particulate matter (PM(10)) was at the highest quartile. Inhalable airborne particulate matter concentrations were connected to relapse occurrence. Poor air quality may enhance the seasonal changes in MS relapse occurrence by an increased susceptibility to transmissible infections.

Air Pollution↗
PubMed2002

The association between reported childhood sexual abuse and breastfeeding initiation.

This study examined the association between self-identified childhood sexual abuse and breastfeeding initiation. A nationally representative sample of 2017 parents with children younger than 3 years was surveyed by telephone about child-rearing needs. Respondents were asked to report childhood sexual abuse and breastfeeding practices. Responses of 1220 biological mothers were analyzed. A possible association between self-reported childhood sexual abuse and breastfeeding initiation was investigated through multivariate logistic regression. Seven percent of the respondents reported experiencing childhood sexual abuse. Women who reported childhood sexual abuse were more than twice (adjusted odds ratio = 2.58; 95% confidence interval = 1.14, 5.85; P = .02) as likely to initiate breastfeeding compared with women who did not report childhood sexual abuse. Parenting attitudes and behaviors were compared to consider whether greater concern with parenting is an explanation for this association. In this nationally representative sample, self-identified childhood sexual abuse is associated with an increased likelihood of breastfeeding initiation.

Adult↗
PubMed2006

Hyperglycemia and nocturnal systolic blood pressure are associated with left ventricular hypertrophy and diastolic dysfunction in hypertensive diabetic patients.

BACKGROUND: The aim of this study was to determine if hypertensive type 2 diabetic patients, when compared to patients with essential hypertension have an increased left ventricular mass index (LVMI) and a worse diastolic function, and if this fact would be related to 24-h pressoric levels changes. METHODS: Ninety-one hypertensive patients with type 2 diabetes mellitus (DM) (group-1 [G1]), 59 essential hypertensive patients (group-2 [G2]) and 26 healthy controls (group-3 [G3]) were submitted to 24-h Ambulatory Blood Pressure Monitoring (ABPM) and echocardiography (ECHO) with Doppler. We calculated an average of fasting blood glucose (AFBG) values of G1 from the previous 4.2 years and a glycemic control index (GCI) (percentual of FBG above 200 mg/dl). RESULTS: G1 and G2 did not differ on average of diurnal systolic and diastolic BP. However, G1 presented worse diastolic function and a higher average of nocturnal systolic BP (NSBP) and LVMI (NSBP = 132 +/- 18 vs 124 +/- 14 mmHg; P < 0.05 and LVMI = 103 +/- 27 vs 89 +/- 17 g/m2; P < 0.05, respectively). In G1, LVMI correlated with NSBP (r = 0.37; P < 0.001) and GCI (r = 0.29; P < 0.05) while NSBP correlated with GCI (r = 0.27; P < 0.05) and AFBG (r = 0.30; P < 0.01). When G1 was divided in tertiles according to NSBP, the subgroup with NSBP> or =140 mmHg showed a higher risk of LVH. Diabetics with NSBP> or =140 mmHg and AFBG>165 mg/dl showed an additional risk of LVH (P < 0.05; odds ratio = 11). In multivariate regression, both GCI and NSBP were independent predictors of LVMI in G1. CONCLUSION: This study suggests that hyperglycemia and higher NSBP levels should be responsible for an increased prevalence of LVH in hypertensive patients with Type 2 DM.

Adult↗
PubMed2000

Mobility impairments and use of screening and preventive services.

OBJECTIVES: Primary care for people with disabilities often concentrates on underlying debilitating disorders to the exclusion of preventive health concerns. This study examined use of screening and preventive services among adults with mobility problems (difficulty walking, climbing stairs, or standing for extended periods). METHODS: The responses of non-institutionalized adults to the 1994 National Health Interview Survey, including the disability and Healthy People 2000 supplements, were analyzed. Multivariable logistic regressions predicted service use on the basis of mobility level, demographic characteristics, and indicators of health care access. RESULTS: Ten percent of the sample reported some mobility impairment; 3% experienced major problems. People with mobility problems were as likely as others to receive pneumonia and influenza immunizations but were less likely to receive other services. Adjusted odds ratios for women with major mobility difficulties were 0.6 (95% confidence interval [CI] = 0.4, 0.9) for the Papanicolaou test and 0.7 (95% CI = 0.5, 0.9) for mammography. CONCLUSIONS: More attention should be paid to screening and preventive services for people with mobility difficulties. Shortened appointment times, physically inaccessible care sites, and inadequate equipment could further compromise preventive care for this population.

Adult↗
PubMed2004

Physicians' choice in using Internet and fax for patient recruitment and follow-up in a randomized controlled trial.

OBJECTIVE: To examine the physicians' preference between Web and fax-based remote data entry (RDE) system for an ongoing randomized controlled trial (RCT) in Japan. METHODS: We conducted a survey among all the collaborating physicians (n = 512) of the CASE-J (Candesartan Antihypertensive Survival Evaluation in Japan) trial, who have been recruiting patients and sending follow-up data using the Web or a fax-based RDE system. The survey instrument assessed physicians' choice between Web and fax-based RDE systems, their practice pattern, and attitudes towards these two modalities. RESULTS: A total of 448 (87.5%) responses were received. The proportions of physicians who used Web, fax, and the combination of these two were 45.9%, 33.3% and 20.8%, respectively. Multivariate logistic regression analyses revealed that physicians 55 years or younger [odds ratio (OR) = 1.9, 95% confidence interval (CI) = 1.1-3.3] and regular users of computers (OR = 4.2, 95% CI = 2.1-8.2) were more likely to use the Web-based RDE system. CONCLUSIONS: This information would be useful in designing an RCT with a Web-based RDE system in Japan and abroad.

Adult↗
PubMed2003

The influence of microvessel density on ovarian carcinogenesis.

OBJECTIVE: Tumor microvessel density, measured by CD31 immunohistochemistry, correlates with survival in patients with ovarian cancer. CA 125 is secreted by most ovarian cancers, and we have previously shown that the rate of decline of CA 125 is also predictive of ovarian cancer survival. Because increased tumor vascularity may allow metastases on one hand, while facilitating the delivery of chemotherapy on the other, we investigated the relationship of tumor microvessel density to preoperative CA 125, residual disease, and the initial response to treatment. METHODS: FIGO stage, grade, age, residual disease, and CD31 microvessel density count were correlated with consecutive patients (n = 202) diagnosed with epithelial ovarian cancer who met entry criteria. The relationship of CD31 staining to preoperative CA 125, and the rate of decline in CA 125 (slope) as a measure of initial response to therapy, was also evaluated based on complete CA 125 data. Spearman correlation and the Wilcoxon rank sum test were used for bivariate analyses. Linear and logistic regression was used for multivariate analysis. RESULTS: There were 21 stage I, 14 stage II, 125 stage III, and 42 stage IV patients diagnosed with epithelial ovarian cancer included in the study. More than half (N = 126) of the patients were optimally cytoreduced. Elevated microvessel density was associated with advanced stage of disease (P = 0.0453), grade (P = 0.0002), and an increased amount of residual disease (P = 0.0144). CA 125 values were higher in patients with residual disease versus patients without residual disease (P = 0.0357), and the decline in the CA 125 (slope) was less steep in patients without residual disease versus patients with residual disease (P = 0.0003). However, the initial response to chemotherapy was unrelated to the microvessel density count as measured by CD31 antibody staining (P = 0.7911). In multivariate analyses, CD31 counts remained significant in relationship to grade. Nonideal slopes, indicating decreased response, were associated with increasing age (P = 0.0008) and residual disease (P = 0.0035). CONCLUSION: Elevated ovarian cancer microvessel density count is related to advanced stage and grade of disease, and compromised potential for cytoreduction. Residual disease is associated with higher CA 125 levels and faster CA 125 decline rates. The rate of decline of CA 125 during the initial response to treatment cannot be predicted based on CD31 counts, confirming a complex relationship between tumor vascularity, metastasis, and response to treatment.

CA-125 Antigen↗
PubMed1992

Blocked arteries and multivariate regression.

Ultrasound blood flow waveforms may be used in the diagnosis of arterial occlusive disease in human legs. We develop a statistical model to predict disease severity, conditional on the ultrasound data and some training data. It belongs to the class of models known as seemingly unrelated regressions, for which the Bayesian predictive density function cannot be evaluated analytically. Allowing for missing components of response vectors in the training data, we describe a first-order approximation to the predictive density, based on a Bayes estimate of the precision matrix. This approximation is then used to generate cross-validated predictions of disease severity in a set of 31 patients. We conclude with a discussion of the results.

Arterial Occlusive Diseases↗