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PubMed2005

Quality of life, disability and handicap in patients with toxic oil syndrome.

AIM: This paper reports an investigation of the quality of life of patients most severely affected by toxic oil syndrome and the association between quality of life and disability variables, handicaps and depression. BACKGROUND: In 1981, an epidemic occurred in Central and Northwestern Spain. The illness, now called toxic oil syndrome (TOS), appeared to be caused by consumption of oil mixtures containing rapeseed oil denatured with aniline and affected over 20,000 individuals. Today, it is classified as a chronic disease that has resulted in a large number of sequelae. METHOD: From the 1031 people classified with permanent disability, a random sample of 292 individuals was selected. A structured interview was carried out to investigate the clinical aspects. The Nottingham Health Profile Questionnaire was used to assess quality of life. To study the relationship between quality of life and disability, handicap and depression, a univariate analysis was carried out. The chi-square test was used for inter-group comparisons. A P-value of 0.05 was adopted as the limit for inclusion of a variable in the multivariate analysis. Multivariate analysis was undertaken using logistic regression. RESULTS: Two hundred and fourteen patients were interviewed (79% response rate). Mean age was 59.3 (sd: 12.7) years. Quality of life mean score was 52.8 (sd: 22.6). The variables associated with poorer quality of life perception were depression [odds ratio (OR) = 9.66, confidence interval (CI) = 3.71-25.15], role-related disabilities (occupation role: OR = 2.82 CI = 1.28-6.22) and mobility (bending/picking up: OR = 4.74, CI = 2.31-9.72), as well as economic problems (OR = 1.62, CI = 1.07-2.46). CONCLUSION: The quality of life of those most severely affected by TOS is poor. Their health profile is characterized by depression and important functional and psycho-social disabilities that limit daily living activities and social roles, and are related to self-perceptions of poor quality of life.

Adult↗

PubMed2006

Risk factors for shoulder and elbow injuries in adolescent baseball pitchers.

BACKGROUND: There is little evidence supporting current safety recommendations for adolescent pitchers. HYPOTHESIS: Pitching practices of adolescent pitchers without history of arm injury will be significantly different from those of adolescent pitchers who required shoulder or elbow surgery. STUDY DESIGN: Case control study; Level of evidence, 3. METHODS: Ninety-five adolescent pitchers who had shoulder or elbow surgery and 45 adolescent pitchers who never had a significant pitching-related injury completed a survey. Responses were compared between the 2 groups using t tests and chi(2) analyses. Multivariable logistic regression models were developed to identify the risk factors. RESULTS: The injured group pitched significantly more months per year, games per year, innings per game, pitches per game, pitches per year, and warm-up pitches before a game. These pitchers were more frequently starting pitchers, pitched in more showcases, pitched with higher velocity, and pitched more often with arm pain and fatigue. They also used anti-inflammatory drugs and ice more frequently to prevent an injury. Although the groups were age matched, the injured group was taller and heavier. There were no significant differences regarding private pitching instruction, coach's chief concern, pitcher's self-rating, exercise programs, stretching practices, relieving frequency, pitch type frequency, or age at which pitch types were first thrown. CONCLUSION: Pitching practices were significantly different between the groups. The factors with the strongest associations with injury were overuse and fatigue. High pitch velocity and participation in showcases were also associated with increased risk for injury. CLINICAL RELEVANCE: New recommendations were made based on these results. Adherence to the recommendations may reduce the incidence of significant injury to adolescent pitchers.

Adolescent↗

PubMed2007

Implementation and use of an electronic health record within the Indian Health Service.

OBJECTIVES: There are limited data regarding implementing electronic health records (EHR) in underserved settings. We evaluated the implementation of an EHR within the Indian Health Service (IHS), a federally funded health system for Native Americans. DESIGN: We surveyed 223 primary care clinicians practicing at 26 IHS health centers that implemented an EHR between 2003 and 2005. METHODS: The survey instrument assessed clinician attitudes regarding EHR implementation, current utilization of individual EHR functions, and attitudes regarding the use of information technology to improve quality of care in underserved settings. We fit a multivariable logistic regression model to identify correlates of increased utilization of the EHR. RESULTS: The overall response rate was 56%. Of responding clinicians, 66% felt that the EHR implementation process was positive. One-third (35%) believed that the EHR improved overall quality of care, with many (39%) feeling that it decreased the quality of the patient-doctor interaction. One-third of clinicians (34%) reported consistent use of electronic reminders, and self-report that EHRs improve quality was strongly associated with increased utilization of the EHR (odds ratio 3.03, 95% confidence interval 1.05-8.8). The majority (87%) of clinicians felt that information technology could potentially improve quality of care in rural and underserved settings through the use of tools such as online information sources, telemedicine programs, and electronic health records. CONCLUSIONS: Clinicians support the use of information technology to improve quality in underserved settings, but many felt that it was not currently fulfilling its potential in the IHS, potentially due to limited use of key functions within the EHR.

Attitude of Health Personnel↗

PubMed1997

Physician concurrence with primary care guidelines for persons with HIV disease.

An anonymous questionnaire was mailed to 3 groups of physicians in British Columbia: 659 registrants of a province-wide human immunodeficiency virus (HIV) drug treatment programme (Group 1); 765 who had had a patient test positive for HIV (Group 2); and a random sample of 484 (Group 3). Questionnaires provided data about: physician's demographic and personal characteristics; HIV-related patient care experience; and 12 knowledge-based items. Responses were received from 65% of Group 1, 68% of Group 2 and 70% of Group 3, with complete information received from 38% of Group 1 and 50% of Groups 2 and 3. Summary knowledge scores were computed by comparing physician responses to recommendations of contemporary guidelines. Regression techniques identified associations between physician characteristics and knowledge scores. Multivariate analysis revealed an inverse relationship between knowledge and physician age in all groups (all P < 0.01). Increased knowledge was associated with the number of currently active HIV-positive patients in Groups 1 and 2 (all P < 0.001), and lack of specialization in Groups 2 and 3 (both P < 0.001).

Adult↗

PubMed2001

The coagulative and cardiorespiratory responses to reamed intramedullary nailing of isolated fractures.

We measured the changes during operation in seven markers of coagulation in a prospective series of 84 patients with fractures of the tibia or femur who were undergoing reamed intramedullary nailing. All patients were also continually monitored using transoesophageal echocardiography to assess marrow embolism. In a subset of 40 patients, intraoperative cardiopulmonary function was monitored, using pulmonary and systemic arterial catheterisation. The procedure produced a significant increase in prothrombin time, activated partial thromboplastin time, the level of prothrombin fragments F1+2 and D-dimers, and a decrease in the fibrinogen level, suggesting activation of both the coagulation and fibrinolytic pathways. There was evidence of both platelet hyper-reactivity and depletion, as estimated by an increase in beta-thromboglobulin levels and a decrease in the platelet count. In the patients who had invasive monitoring there was an incremental increase in mean pulmonary arterial pressure, with the changes being greatest during insertion of the guide-wire and reaming. The change in markers of coagulation, pulmonary artery pressure and arterial oxygen partial pressures correlated with the intraoperative embolic response. Greater changes in these parameters were observed during stabilisation of pathological fractures and in those patients in whom surgery had been delayed for more than 48 hours. Seven patients with pathological fractures developed more severe hypoxic episodes during reaming, which were associated with significantly greater arterial hypoxaemia, a fall in the right ventricular ejection fraction and an increase in the mean pulmonary artery pressure, pulmonary capillary wedge pressure, central venous pressure and the pulmonary vascular resistance index. These changes suggested that the patients had transient intraoperative right heart strain. Eight patients developed significant postoperative respiratory compromise. They all had severe intraoperative embolic responses and, in the three who had invasive monitoring, there was a significantly greater increase in pulmonary artery pressure and alveolar-arterial oxygen gradient, and a fall in the ratio of arterial partial pressure of oxygen to the inspired oxygen concentration. Operative delay, intraoperative paradoxical embolisation and the scores for the severity of the coagulative and embolic responses were predictive of the development of postoperative respiratory complications on univariate logistic regression analysis. On multivariate analysis, however, only the embolic and coagulative scores were significant independent predictors of respiratory complications.

Cardiovascular Diseases↗

PubMed1999

Expression of p21 and MDM-2 proteins on tumor cells in responding and non-responding patients with Hodgkin's disease.

Since the prevention of apoptosis can produce resistance to chemotherapy, abnormal expression of oncoproteins engaged in the regulation of this phenomenon in tumor cells may give some prognostic information in patients with neoplasma. To assess this problem in Hodgkin's disease (HD), the cellular expression of two p53 downstreams proteins p21 and MDM-2 was evaluated in the lymph nodes specimens obtained from 68 patients at the time of diagnosis, and compared with some clinical and pathological data. Positive immunoreaction for p21 and MDM-2 on Reed-Sternberg/Hodgkin's (R-S/H) cells was found in a majority of cases (58.8 and 63.2%, respectively). High expression of p21 protein correlated with poor response to the first-line treatment and disease free survival in both univariate and multivariate regression analysis, whereas expression of MDM-2 did not give prognostic information in patients with HD. Expression of p21 and MDM-2 was also compared with p53 protein immunoreactivity of R-S/H cells. The p21+/p53+ immunophenotype occurred to give particularly negative prognostic information in patients with HD. Diversity of p21/MDM-2/p53 patterns of R-S/H cells observed in particular patients may reflect heterogeneity of apoptosis regulatory mechanisms, as well as differences in p53 gene status.

Adolescent↗

PubMed1991

[Left ventricular filling studied by echo-Doppler in hypertensive and normotensive subjects].

Purpose of the study was to evaluate the influence of different clinical and echocardiographic parameters on left ventricular diastolic filling in a group of 66 mild to moderate hypertensive subjects (mean age = 45.9 +/- 13.9 yrs) and in 49 normotensive controls (mean age = 44.2 +/- 15.9 yrs). All subjects underwent an echocardiographic study with pulsed Doppler evaluation of left ventricular filling. In the hypertensives, a noninvasive 24-hour blood pressure monitoring was performed. The ratio of early to atrial peak diastolic filling velocity (VmaxE/VmaxA) and the ratio between the respective velocity flow integral (Earea/Aarea) were significantly lower in the hypertensives compared to the normotensives (p less than 0.001). As within the hypertensives, office systolic blood pressure, average 24-hour mean blood pressure (24MBP), left atrial dimensions, and left ventricular mass index (MAXIND) were related both to age and diastolic filling. To study the relation between these parameters and diastolic filling a partial correlation test was used. The only variable related to diastolic filling, independently of age, was 24MBP (VmaxE/VmaxA vs 24MBP: r = -0.307, p less than 0.05, Earea/Aarea vs 24MBP: r = -0.261, p less than 0.05). Linear multivariate analysis using the method of stepwise regression established that age, 24MBP and heart rate were responsible for 75% of the VmaxE/VmaxA variance in the hypertensive group. To evaluate if the difference between the indexes of diastolic filling in the normotensives and the hypertensives varied according to age, we divided each group into two classes of subjects older and younger than 40 yrs. Under the age of 40 only VmaxE/VmaxA was significantly different in the two groups (p less than 0.05), while in the subjects older than 40 yrs both VmaxE/VmaxA and Earea/Aarea differed to a great level of statistical significance (p less than 0.001). The results of the present study allow the following conclusions: 1) age has the greatest influence on diastolic filling in both hypertensive and normotensive individuals. Diastolic filling is impaired in mild to moderate hypertension, when systolic function is still normal; 2) the worsening of diastolic filling determined by hypertension is more evident in the subjects greater than 40 yrs; 3) the only clinical variable that influences diastolic filling, independently of age, is 24MBP, while office blood pressure, MAXIND and left ventricular ejection fraction do not seem to be related to this clinical entity.

Adolescent↗

PubMed1997

PSA evolution: a prognostic factor during treatment of advanced prostatic carcinoma with total androgen blockade. Data from a Belgian multicentric study of 546 patients.

OBJECTIVES: To study the prognostic value of the prostate-specific antigen (PSA) response and its relationship with other initial prognostic factors during the treatment of advanced prostatic carcinoma with total androgen blockade. METHODS: Five hundred forty-six patients with advanced loco-regional (M0) or distant metastatic (M1) prostatic carcinoma treated with flutamide combined with either orchiectomy or LHRH analogues were included in this analysis. Initial patients characteristics and the PSA response were evaluated in relation to progression-free survival using a univariate and multivariate (Cox regression) analysis. RESULTS: The following prognostic factors were indicative of a decrease in progression-free survival: the absence of PSA normalization (< 4 ng/ml) after 3 or 6 months, M1 stage, high G grade, ECOG performance status > 1, presence of pain and absence of dysuria. In M1 patients the combination of PSA normalization after 3 or 6 months with initial G grade and ECOG performance status had the strongest predictive value. CONCLUSIONS: This study demonstrates that PSA normalization after 3 or 6 months along with initial tumor stage, grade and health status of the patient are the most important prognostic factors related to progression-free survival in the hormonal treatment of advanced prostatic carcinoma.

Aged↗

PubMed2005

Osteoporosis beliefs and antiresorptive medication use.

OBJECTIVE: Although a number of prescription medications are effective for the prevention and treatment of osteoporosis, little is known about the role of beliefs and attitudes in women decisions to use these drugs. The objectives of this study were (1) to assess the role of beliefs and attitudes regarding osteoporosis and prescription antiresorptive drugs in the decision to use newer antiresorptive medicines (such as bis-phosphonates, selective estrogen receptor modulators, and calcitonin nasal) and (2) to assess the role of these same beliefs and attitudes in the decision to use hormone therapy. DESIGN: Data were collected using a cross-sectional survey mailed to 1700 community dwelling women age 45 and older residing in Minnesota. Respondents completed measures of health belief model constructs, medication profiles and demographics. Data were analyzed using multivariate logistic regression models. RESULTS: A total of 983 usable survey forms were returned, yielding an adjusted response rate of 60.7%. More than one quarter of respondents reported using a prescription antiresorptive agent, with 90 (9.2%) currently taking a newer antiresorptive agent and 163 (16.6%) using hormone therapy. Several health belief model components were predictive of newer antiresorptive medicine use, including higher perceptions of susceptibility to osteoporosis (OR 1.34, 95% CI 1.20-1.49), perceptions of strong benefits of antiresorptive medicines (OR 1.34, 95% CI 1.10-1.63), and perceptions of few barriers to the use of antiresorptive medicines (OR 0.51, 95% CI 0.38-0.67). Several cues to action also were predictive of newer antiresorptive medicine use. Use of hormone therapy was associated with a single cue to action (being tested for osteoporosis (OR 1.74, 95% CI 1.14-2.66) and the perception of few barriers to the use of prescription antiresorptives (OR 0.65, 95% CI 0.55-0.77). CONCLUSION: Several health belief model constructs were associated with the decision to use newer antiresorptive drugs relative to no prescription therapy. However, few model components as operationalized in this study were predictive of the use of hormone therapy. Although the health belief model appears to provide a plausible model of the decision to undertake newer antiresorptive drug therapy, it explains little about women use of hormone therapy.

Aged↗

PubMed2001

Predictive factors for regression of gastric MALT lymphoma after anti-Helicobacter pylori treatment.

BACKGROUND AND AIMS: Discrepant remission rates (41-100%) have been reported for patients with localised low grade gastric mucosa associated lymphoid tissue (MALT) lymphoma after eradication of Helicobacter pylori. The aim of this study was to explain these discrepancies and to determine the predictive factors of gastric lymphoma regression after anti- H pylori treatment. PATIENTS AND METHODS: Forty six consecutive patients with localised gastric MALT lymphoma (Ann Arbor stages I(E) and II(E)) were prospectively enrolled. All had gastric endoscopic ultrasonography and H pylori status assessment (histology, culture, polymerase chain reaction, and serology). After anti-H pylori treatment, patients were re-examined every four months. RESULTS: Histological regression of the lymphoma was complete in 19/44 patients (43%) (two lost to follow up). Median follow up time for these 19 responders was 35 months (range 10-47). No regression was noted in the 10 H pylori negative patients. Among the 34 H pylori positive patients, the H pylori eradication rate was 100%; complete regression rate of the lymphoma increased from 56% (19/34) to 79% (19/24) when there was no nodal involvement at endoscopic ultrasonography. There was a significant difference between the response of the lymphoma restricted to the mucosa and other more deep seated lesions (p<0.006). However, using multivariate analysis, the only predictive factor of regression was the absence of nodal involvement (p<0.0001). CONCLUSION: In H pylori positive patients with localised gastric MALT lymphoma, carefully evaluated and treated without any lymph node involvement assessed by endoscopic ultrasonography, complete remission of lymphoma was reached in 79% of cases.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2006

Multivariable modeling of radiotherapy outcomes, including dose-volume and clinical factors.

PURPOSE: The probability of a specific radiotherapy outcome is typically a complex, unknown function of dosimetric and clinical factors. Current models are usually oversimplified. We describe alternative methods for building multivariable dose-response models. METHODS: Representative data sets of esophagitis and xerostomia are used. We use a logistic regression framework to approximate the treatment-response function. Bootstrap replications are performed to explore variable selection stability. To guard against under/overfitting, we compare several analytical and data-driven methods for model-order estimation. Spearman's coefficient is used to evaluate performance robustness. Novel graphical displays of variable cross correlations and bootstrap selection are demonstrated. RESULTS: Bootstrap variable selection techniques improve model building by reducing sample size effects and unveiling variable cross correlations. Inference by resampling and Bayesian approaches produced generally consistent guidance for model order estimation. The optimal esophagitis model consisted of 5 dosimetric/clinical variables. Although the xerostomia model could be improved by combining clinical and dose-volume factors, the improvement would be small. CONCLUSIONS: Prediction of treatment response can be improved by mixing clinical and dose-volume factors. Graphical tools can mitigate the inherent complexity of multivariable modeling. Bootstrap-based variable selection analysis increases the reliability of reported models. Statistical inference methods combined with Spearman's coefficient provide an efficient approach to estimating optimal model order.

Carcinoma, Non-Small-Cell Lung↗

PubMed2005

Macular retinoblastoma managed with chemoreduction: analysis of tumor control with or without adjuvant thermotherapy in 68 tumors.

OBJECTIVE: To evaluate the effectiveness of chemoreduction alone and chemoreduction with thermotherapy for macular retinoblastoma. DESIGN: Prospective, nonrandomized, single-center case series. SETTING: Ocular Oncology Service at Wills Eye Hospital of Thomas Jefferson University in conjunction with the Division of Oncology at the Children's Hospital of Philadelphia (Pa). PARTICIPANTS: There were 68 macular retinoblastomas in 62 eyes of 49 patients managed with chemoreduction from January 1995 through January 2003. Intervention All patients received 6 cycles of intravenous chemoreduction using vincristine, etoposide, and carboplatin. The patients were then treated according to 1 of 2 approaches: chemoreduction alone with no adjuvant focal therapy (group A) or chemoreduction combined with adjuvant foveal-sparing thermotherapy to each macular retinoblastoma (group B). Main Outcome Measure Tumor recurrence. RESULTS: Of the 68 tumors, 28 were in group A and 40 were in group B. A comparison of both groups revealed that the tumors were similar with regard to clinical features. The mean tumor basal dimension was 12.3 mm for group A and 12.1 mm for group B, and the mean tumor thickness was 6.8 mm for group A and 6.1 mm for group B. Tumors in group A occupied a mean of 71% of the macula, and those in group B occupied 74% of the macula. Following treatment, Kaplan-Meier estimates revealed that group A tumors showed recurrence in 25% by 1 year and 35% by 4 years whereas those in group B showed recurrence in 17% by 1 year and 17% by 4 years. All recurrences were treated with additional focal thermotherapy, cryotherapy, or plaque radiotherapy except for 1 that required external beam radiotherapy and 1 that required enucleation, both in group A. Univariate analysis revealed that predictors of tumor recurrence were intraretinal growth pattern (vs endophytic); small tumor basal dimension (less than 3 mm and occupying a smaller percentage of the macula); absence of subretinal fluid, subretinal seeds, and vitreous seeds; and chemoreduction response with less tumor calcification and tumor regression of type 0 (complete disappearance without a scar). By multivariate analysis, the most important factors predictive of tumor recurrence were smaller macular tumor size (judged by percentage of the macula occupied by the tumor), absence of subretinal or vitreous seeds, and unilateral disease. CONCLUSIONS: Treatment of macular retinoblastoma with chemoreduction plus adjuvant foveal-sparing thermotherapy provides tumor control of 83% by 4 years, and this is slightly more favorable than chemoreduction alone, which provides control of 65% by 4 years. Tumors most destined for recurrence are small tumors.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2006

The effect of postprostatectomy external beam radiotherapy on quality of life: results from the Cancer of the Prostate Strategic Urologic Research Endeavor.

BACKGROUND: Postprostatectomy salvage radiotherapy may improve prostate-specific antigen (PSA) progression-free survival, but little is known about its effect on quality of life. METHODS: From the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) data base, 1289 patients who had undergone radical prostatectomy (RP) without neoadjuvant or adjuvant hormone therapy completed validated health-related quality of life (HRQOL) questionnaires. Of these, 69 patients also received salvage radiotherapy at a median of 14 months after RP. The University of California-Los Angeles Prostate Cancer Index and the 36-item short form SF-36 questionnaire were used to compare HRQOL 12 to 18 months after external beam radiotherapy or 26 to 32 months after RP alone. Those responses also were compared with HRQOL responses from 55 men with data prior to and 12 to 18 months after primary radiotherapy. Multivariate regression identified differences between treatment groups. RESULTS: Men who underwent salvage radiotherapy were younger (P = .03) and had lower incomes (P = .01) than men who underwent RP alone; they also were younger than men who underwent primary radiotherapy (P < .01). In addition, men who received salvage radiotherapy were more likely than men who underwent RP alone to have clinically high-risk prostate cancer (P < .01). Multivariate analyses revealed that men who received salvage radiotherapy experienced more marked decrements in sexual function (P = .01) and bowel function (P = .03) than men who underwent RP alone. Salvage radiotherapy led to less impairment of sexual function (P < .01) and less sexual bother (P = .04) than primary radiotherapy. CONCLUSIONS: Although salvage radiotherapy is associated with unclear survival benefits, it adversely affects sexual and bowel function. Until randomized clinical trials demonstrate disease-specific survival benefits for salvage radiotherapy, the HRQOL detriments of additional therapy must be weighed against improved PSA progression-free survival.

Aged↗

PubMed1980

A case-control study of diet and colo-rectal cancer.

A case-control study of cancer of the colon and rectum has been conducted in Calgary, Alberta and Toronto, Ontario, Canada. A total of 348 cases of cancer of the colon and 194 cases of cancer of the rectum were individually matched by age, sex and neighbourhood of residence to 542 population controls and frequency match to 535 hospital controls who had undergone an abdominal operation. Each subject received a personal medical history questionnaire and a quantitative diet history questionnaire. Data on a number of potential non-nutrient risk factors for bowel cancer and on the consumption of 9 nutrients in the 2-month period up to 6 months before interview were analysed. The dietary data thus refer to recent diet consumed in a period antedating the diagnosis of, and in most cases symptoms from, large-bowel cancer in the cases, and a corresponding time period in the controls. The major findings were an elevated risk for those with a history of bowel polyps, and for those with an elevated intake of calories, total fat, total protein, saturated fat, oleic acid and cholesterol. No association was seen with an elevated intake of crude fibre, Vitamin C and linoleic acid. The nutrients for which an increased risk was demonstrated were highly correlated, though multivariate analysis using logistic regression indicated highest risk for saturated fat, with evidence of a dose-response relationship. The findings in both cancer sites, both sexes and with both sets of controls were quantitatively very similar. The population-attributable risk for colon and rectal cancer combined was estimated from the neighbourhood controls to be 41% for males and 44% for females for saturated fat intake and 9.8% and 6.4% respectively for any history of polyps.

Adult↗

PubMed2005

Impact of tumor size on the long-term survival of patients with early stage renal cell cancer.

As the biological behaviour of even early stage renal cell cancer (RCC) strongly correlates with tumor size, it has been argued that the inclusion of RCC up to a maximum diameter of 7 cm into a common subgroup classified as T1 according to the 5th edition of the TNM system would not adequately represent the different biological aggressiveness of these malignancies. Taking this into account, the TNM classification, which now categorizes T1 RCC as T1a and T1b according to a cutoff size of 4 cm, was recently modified. However, only a few larger investigations, mainly based on univariate statistical analyses, that support the suitability of this cutoff are at present available from the literature. Therefore, it was the aim of the present investigation to determine the tumor size that best separates patients with low responses from those with high risk for tumor progression by univariate (log rank test) and multivariate (Cox regression model) statistical analyses. Between 1981 and 2000, 652 patients (443 males and 209 females) underwent tumor nephrectomy in our clinic for the diagnosis of RCC. Of these, 243 patients revealed primary tumors with a local growth not extending beyond the renal capsula at the time of surgery. For the different cutoff levels (starting from 2 cm in increments of 1 cm up to 8 cm) that were selected to subdivide the patients into groups according to the maximum tumor diameter, the correlation between tumor size and overall survival was determined by univariate and multivariate statistical analyses. It became evident that although during univariate analysis the prognostic value of a cutoff size of 4 cm was confirmed, multivariate analysis identified the highest relative risk for cause-specific death (2.93) for patients having tumors larger than 5 cm in maximum diameter. Therefore, the 5 cm cutoff seems to best determine the clinical prognosis of patients undergoing tumor nephrectomy for early stage RCC. The present study demonstrates the need for multivariate statistical approaches when the latest modification of the TNM classification system is critically evaluated.

Adult↗

PubMed1997

Ribavirin enhances the efficacy but not the adverse effects of interferon in chronic hepatitis C. Meta-analysis of individual patient data from European centers.

BACKGROUND/AIMS: This study aimed to obtain a more precise estimation of the efficacy and tolerability of interferon-ribavirin combination therapy for chronic hepatitis C. METHODS: A meta-analysis was carried out of individual patient data comprising about 90% of the published experience with combination therapy. The study was set in four European university-affiliated liver referral centers. A total of 186 individuals with chronic hepatitis C who had participated in three randomized controlled trials and one open study were selected for the study. Fifty-one had received ribavirin monotherapy (1000-1200 mg/day), 37 interferon monotherapy (3 MU 3x/week) and 78 interferon-ribavirin combination therapy (dosage as for monotherapy) for 6 months. Twenty patients served as controls. Follow-up after therapy was 6 months. Data analysis was by the multivariate logistical regression method. RESULTS: The primary outcome measure for efficacy was the percentage with a sustained response (ALT normalization and HCV RNA negativity 6 months after therapy). The sustained response rate was significantly higher for interferon-ribavirin combination therapy than for interferon or ribavirin monotherapy (odds ratio IFN-Riba vs IFN = 9.8, 95% CI 1.9-50). The estimated probability of sustained response following interferon-ribavirin combination therapy was 51% for patients without previous IFN therapy, 52% for patients with previous IFN therapy and response-relapse, and 16% for previous IFN non-responders. No serious adverse events were observed and less than 10% withdrew. CONCLUSIONS: The efficacy of interferon-ribavirin therapy appears to be enhanced two- to threefold over interferon monotherapy in all major subgroups of chronic hepatitis C patients tested. In view of its acceptable toxicity profile, interferon-ribavirin combination therapy is a candidate for the new standard therapy for chronic hepatitis C.

Adult↗

PubMed2003

Depressed versus nondepressed young adult tobacco users: differences in coping style, weight concerns and exercise level.

Undergraduates age 18 to 24 years (n=656) completed questionnaires assessing tobacco use, depressive symptoms, coping responses, weight concerns, and exercise. The majority of participants were female (72%), White/non-Hispanic (95%), and in the 1st or 2nd year of college (80%). Current tobacco users (n=236) had a higher frequency of depression (40%) than never tobacco users (32%; p=.05). Tobacco users classified as depressed (Center for Epidemiological Studies Depression Scale [CES-D] score a 16) reported greater weight concerns and more frequent maladaptive coping in response to negative mood than tobacco users classified as nondepressed (CES-D score<16). Multivariate logistic regression analysis indicated that higher maladaptive coping and lower level of exercise were significantly associated with depression among tobacco users.

Adaptation, Psychological↗

PubMed2004

Resorptive drug use among community-dwelling women in Minnesota.

PURPOSE: The frequency of and factors associated with the use of resorptive medications among community-dwelling women age 45 years or older in Minnesota were studied. METHODS: The study was a secondary analysis of a cross-sectional survey mailed to 1700 community-dwelling women age 45 years or older in Minnesota. The survey was designed to collect information about women's attitudes and beliefs regarding osteoporosis and antiresorptive medications. Respondents were also asked to give a detailed list of all prescription medications they currently used, including the quantity and directions for use. Descriptive statistics were calculated for the demographic, health, and medication-use characteristics of all respondents and for the subset of those using resorptive medications. Chi-square analysis and logistic regression were used to test bivariate and multivariate relationships. RESULTS: Of the 990 usable surveys returned (adjusted response rate of 61.1%), 84 respondents (8.5%) reported using a resorptive drug. Age, health status, and the use of health care services (monthly physician visits and prescription use) were associated with resorptive drug use, controlling for other variables in the model. Women using resorptive medications were nearly 2.5 times more likely to report osteoporosis and osteopenia than women not using these medications. CONCLUSION: The use of resorptive medications in community-dwelling women in Minnesota was highest among those 75-84 years of age, women who were in poor health, and those frequently using health care services. These women were more likely to report using newer antiresorptive medications but were not more likely to use hormone therapy or calcium supplementation.

Aged↗