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The relation between purulent manifestations and antibiotic treatment of upper respiratory tract infections.

OBJECTIVE: To describe the clinical features of patients diagnosed with upper respiratory tract infections (URIs), and determine which clinical features are associated with antibiotic use. DESIGN: Prospective cohort study. SETTING: Three ambulatory care practices at a group-model HMO in the Denver metropolitan area. PATIENTS: Adults (aged 18 years or older) seeking care for acute respiratory illnesses. MEASUREMENTS: Clinical features were documented on standardized encounter forms. Clinician type, secondary diagnoses, and antibiotic treatment were extracted from administrative databases. Results are presented as adjusted odds ratios (ORs) with 95% confidence intervals (CIs). MAIN RESULTS: Antibiotics were prescribed to 33% (95% CI 28%, 38%) of patients diagnosed with URI, after excluding patients with coexisting antibiotic-responsive conditions (e.g., sinusitis, pharyngitis) or a history of cardiopulmonary disease. Multivariate logistic regression analysis identified tobacco use (OR 2.8; 95% CI 1.5, 5.1), history of purulent nasal discharge (OR 2.0; 95% CI 1.1, 3.6) or green phlegm (OR 4.8; 95% CI 2.1, 11.1), and examination findings of purulent nasal discharge (OR 5.2; 95% CI 2.4, 11.2) or tonsillar exudate (OR 3.7; 95% CI 1.1, 12.1) to be independently associated with antibiotic use. The majority of patients treated with antibiotics (82%) had at least one of these factors present. CONCLUSIONS: Antibiotic treatment of URIs is most common when purulent manifestations are present. Efforts to reduce antibiotic treatment of URIs should educate clinicians about the limited value of purulent manifestations in predicting antibiotic-responsive disease.

Acute Disease

A prospective, randomized double-blind trial comparing metoclopramide alone with metoclopramide plus dexamethasone in preventing emesis induced by high-dose cisplatin.

We observed 50 patients receiving high-dose cisplatin-based chemotherapy in a prospective, randomized double-blind trial. One group received metoclopramide (MCP) alone (total dose, 6 mg/kg), whereas the other group was given dexamethasone (DMS) (total dose, 60 mg) in addition to MCP. The patient characteristics of the two groups were comparable, confirming satisfactory randomization. Multivariate regression analysis failed to show any statistical significance in the antiemetic response between the two treatment groups. However, female patients receiving Adriamycin (Adria Laboratories, Columbus, OH) concurrently and obese persons exhibited more vomiting. The overall antiemetic response rate was 66%. Because the side effects were minimal, a higher dose of MCP is expected to improve emetic control without increasing toxicity. The use of a 36-hour assessment period in our study gave more meaningful data. An exponential increase in the dose of MCP is probably required, with respect to weight, to obtain the same antiemetic efficacy.

Adult

[Inadequate fruit and vegetable consumption in Switzerland: results of the Swiss Health Survey 1992/93].

Inadequate consumption of fruit and vegetables increases the risk of various (chronical) diseases. It is therefore recommended to eat at least three portions of vegetables and two portions of fruit every day. The present study aims to determine the prevalence of inadequate fruit and vegetable (potatoes are not regarded as vegetables in Switzerland) consumption in Switzerland and to determine sociodemographic and lifestyle correlates of inadequate consumption. Data presented in this study were taken from the first national representative health survey for Switzerland (conducted 1992/1993) including 7930 men and 7358 women (response rate 71%), age 15 and over. Bivariate analyses and multivariate logistic regressions controlling for sociodemographic and lifestyle factors were done. Inadequate consumption of fruit and vegetables was common among the study population. Less than daily consumption of fruit was reported by about 30%, of vegetables by 17%. About 25% of study participants do not eat fruit or vegetables every day, for 11% the consumption of both is insufficient. Men, young people, study participants with a low educational background, people living in the French and Italian speaking part of Switzerland, smokers and participants with low physical activity reported more often inadequate fruit and vegetable intake than women, older people, well educated study participants, inhabitants of the German speaking part of Switzerland, nonsmokers, and less physically active people. These results stress the need for nutrition education programs aimed at increased consumption of fruit and vegetables in Switzerland.

Adolescent

Analysis of relationships between symptoms and environmental factors over time.

Weekly respiratory symptom information was obtained on a random population of 3800 whites in Tucson. We asked weekly about 14 symptoms representing acute respiratory illnesses (ARI), rhinitis (Rh), and other conditions. The denominator for each week was about 80 randomly chosen subjects from the study population. Interactions of the air pollutants total suspended particulate, oxidants, carbon monoxide, nitrogen oxides for the basin, meteorological information, and aero-allergens were examined. The temporal and spatial interactions between the weekly symptoms and the environmental factors were tested utilizing multivariate methods such as Fourier analyses, multiple regression, and the stimulus-response method, adjusting for lags and controlling for season. Multiple regressions with a smoothing function (using fourier or other methods) yield significant correlations between symptoms and the environmental factors, and separate the ARI's from the Rh's and the miscellaneous symptoms.

Air Pollution

Trigeminal numbness and tic relief after microvascular decompression for typical trigeminal neuralgia.

OBJECTIVE: After most operative treatments for trigeminal neuralgia, long-term tic relief is closely correlated with postoperative numbness in the trigeminal distribution. Microvascular decompression (MVD) is proposed to relieve tic through a nontraumatic mechanism. We investigated the relationship between postoperative trigeminal numbness and tic relief in a large, prospectively followed cohort of patients treated with MVD for typical trigeminal neuralgia. METHODS: Of 1204 patients who underwent MVD for typical tic during a 20-year period, 522 had single MVDs on a single side, had not undergone ablative trigeminal procedures before or after MVD, and were still being followed in 1994. In 1994, patients graded facial numbness using a questionnaire (response rate, 92%) with a 5-point scale. Multivariate Cox and logistic regression methods were used. The analyses were adjusted for the time that had passed between the performance of MVD and the completion of the questionnaire (minimum, 2 yr). RESULTS: Seventeen percent of patients reported some degree of persistent facial numbness. Decompression of a vein at MVD (odds ratio, 2.5) and failure to find compression by the superior cerebellar artery (odds ratio, 2.0) independently predicted postoperative facial numbness, which in turn predicted postoperative burning and aching facial pain (odds ratio, 5.2-5.9). A trend toward worse outcome was noted in patients with numb faces (P = 0.3). Similar findings were noted in subgroups of patients in whom the superior cerebellar artery was decompressed at MVD (n = 381) and in whom a superior cerebellar artery with no vein was found (n = 120). In the latter subgroup, facial numbness (5.8% of patients) significantly predicted worse long-term outcome (P = 0.03). CONCLUSION: We found no evidence that postoperative trigeminal numbness predicts relief of typical tic after MVD. Trigeminal numbness was related to operative findings at MVD and predicted postoperative burning and aching facial pain. To minimize postoperative facial dysesthesia, trauma to the trigeminal root during MVD should be avoided when possible.

Decompression, Surgical

Physical workload and ergonomic factors associated with prevalence of back and neck pain in urban transit operators.

STUDY DESIGN: Back and neck pain was studied cross-sectionally in 1,449 urban transit drivers by linking medical data, self-reported ergonomic factors, and company records on job history. OBJECTIVES: The goal was to examine the relation between physical workload, ergonomic factors, and the prevalence of back and neck pain. SUMMARY OF BACKGROUND DATA: Researchers, to date, have not found an independent effect of ergonomic factors on back and neck pain while accounting for the effects of past and current physical workload. METHODS: Self-reported ergonomic factors, vehicle type, physical workload (measured as duration of driving), height, weight, age, and gender were analyzed in relation to back and neck pain, using multivariable logistic regression models. RESULTS: Physical workload showed a positive dose-response relation with back and neck pain after controlling for vehicle type, height, weight, age, and gender. The odds ratio for 10 years of driving was 3.43. Additional adjustment for ergonomic factors decreased this odds ratio to 2.55. Six out of seven ergonomic factors were significantly related to the prevalence of back and neck pain after adjustment for age, gender, height, weight, and physical workload. Problems with adjusting the seat had the largest effect (odds ratio = 3.52). Women had back and neck pain twice as frequently as men. CONCLUSION: The results support the hypothesis of a causal role of physical workload for the development of back and neck pain. Ergonomic factors partially mediated the risk of back and neck pain associated with driving, suggesting a potential for prevention of back and neck pain by ergonomic redesign of transit vehicles. Elevated risks for back and neck pain for female drivers were not explained by anthropometric and ergonomic factors.

Adult

Clinical significance of portal lymphoid aggregates/follicles in Chinese patients with chronic hepatitis C.

OBJECTIVE: Portal lymphoid aggregates/follicles (lymphoid A/F) is a characteristically histological finding in patients with chronic hepatitis C. We assessed the prevalence of lymphoid A/F in Chinese patients with chronic hepatitis C and evaluated the correlation of this phenomenon with clinical, biochemical, immunological, virological, and other histological features of these patients. METHODS: Eighty-nine Chinese patients with chronic hepatitis C were enrolled and portal lymphoid A/F was evaluated in liver biopsy. Clinical, biochemical, immunological, histological, and virological data, including serum HCV RNA titer and HCV genotype and the response to interferon therapy, were compared between patients with and without portal lymphoid A/F. RESULTS: Twenty-nine (33%) of 89 patients with chronic hepatitis C had portal lymphoid A/F. Patients with lymphoid A/F had a significantly higher frequency of HCV genotype 1b infection (p = 0.039) and had a significantly higher mean score of bile duct damage, periportal necroinflammation, and portal inflammation in liver histologies when compared with patients without lymphoid A/F. No significant difference in sex distribution, mean age, history of blood transfusion, serum liver biochemistry, presence of serum autoantibodies/cryoglobulinemia, serum viral titer, and response to interferon therapy was noted between the two groups. Multivariate logistic regression analysis showed HCV genotype 1b infection and periportal necroinflammation were significant independent predictors associated with portal lymphoid A/F. CONCLUSIONS: The presence of portal lymphoid A/F in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection and periportal necroinflammation.

Biopsy

[Interferon treatment of chronic hepatitis C--assessment of predictive factors to the effect of interferon treatment using multivariate analysis with the logistic regression model].

We treated 156 chronic hepatitis C patients with alpha-interferon (IFN) and assessed the response rate and the predictive factors to the effect of IFN treatment. Complete response (CR) rate was 39.1%, and CR with serum HCV-RNA disappearance rate was 29%. CR to IFN treatment was dependent on HCV serotype and serum HCV-RNA. Patients of serotype II and low serum HCV-RNA were effective to IFN treatment.

Adult

Statistical modeling of dose-response relationships in clinical trials--a case study.

This paper presents a model-based assessment of the relationship between the dose of a test treatment and response. The data set used in the analysis describes the results of two clinical trials that were designed to assess the dose-response relationship of a test treatment. The models described in the paper are fit using weighted regression as implemented by the SAS procedure CATMOD. Relationships between weighted regression and other similar procedures are discussed.

Anticholesteremic Agents

HLA-DR2, a marker for class I antigen sensitization.

After analysis of 423 hemodialysis patients in a transfusion program and 461 cadaver-donor renal transplants, we found that HLA-DR2 frequency was significantly higher in the responder (36%) than in the nonresponder patient group (19%), according to the percentage of PRA (panel reactive antibodies). Among DR2+ patients, the percentage of hypersensitized patients was twice that of DR2- patients. Graft survival curves in cadaver-donor renal transplants indicated a significantly lower survival when recipients were DR2+, even in recipient-donor pairs identical for class II antigens but mismatched for class I antigens. The prognostic probability of low response to transfusions by a stepwise logistic regression analysis showed the influence of sex and DR2 phenotype. By multivariant discriminant analysis, we found that the DR2 phenotype was one of the most influential transfusion sensitization risk factors. Our preliminary conclusion is that DR2 can be related to immune responsiveness to class I antigens.

Antilymphocyte Serum

Physicians, pharmaceutical sales representatives, and the cost of prescribing.

OBJECTIVE: To evaluate the influence of primary care physicians' attitudes toward and use of information provided by pharmaceutical representatives on prescribing costs in ambulatory practice. DESIGN: A mailed questionnaire collected information about physician demographic and practice characteristics and attitudes toward and use of information provided by pharmaceutical representatives. PARTICIPANTS: Kentucky physicians practicing primary care adult medicine (family medicine, general practice, general medicine; n = 1603). MAIN OUTCOME MEASURE: Relative cost of prescribing, based on physician responses to treatment choices for ambulatory clinical scenarios in primary care. A multivariable regression model assessed predictive relationships between independent variables and prescription costs. RESULTS: Four hundred forty-six returned questionnaires were suitable for analysis. No significant differences were noted in age, gender, days worked per week, or years since graduation between responders and a sample of nonresponders. A significant positive correlation was found between physician cost of prescribing and perceived credibility, availability, applicability, and use of information provided by pharmaceutical representatives (P < .01, Pearson's Product-Moment Correlation Coefficient). Physicians in academic or hospital-based practice settings had significantly lower prescribing costs than physicians in nonacademic and nonhospital practices (P = .001, analysis of variance). Frequency of use of information provided by pharmaceutical representatives (P = .01, multiple linear regression) and the group practice setting (P = .02, multiple linear regression) remained significant, independent positive predictors of cost in the multivariable regression model. CONCLUSIONS: Frequency of use of information provided by pharmaceutical representatives and the group practice, nonacademic and nonhospital setting may be associated with increased primary care physician prescribing costs.

Attitude of Health Personnel

Diffusion of innovative approaches to managing hypoplastic left heart syndrome.

OBJECTIVE: To study the perceptions of outcome and the diffusion into practice of innovative approaches such as palliative surgery and heart transplantation to treat hypoplastic left heart syndrome. DESIGN: A forced-choice questionnaire was sent to 108 US neonatology section heads. Responses were analyzed using Wilcoxon matched pairs, chi 2 analysis, and multivariant logistic regression. RESULTS: Ninety-three questionnaires (86%) were returned. All respondents discussed palliative surgery or transplantation or both with parents; 71 (76%) of 93 also discussed comfort care. Nineteen (24%) of 80 recommended comfort care only, 51 (64%) of 80 recommended surgery only, and 10 (12%) of 80 recommended both. Of the 61 respondents recommending one or both surgical procedures, palliative surgery was recommended by 44 and transplantation by 33. Respondents perceived that transplantation was associated with a lower 1-year mortality than palliative surgery (P < .001) and with a better quality of life (P < .001). CONCLUSIONS: Palliative surgery and transplantation are widely used to treat hypoplastic left heart syndrome. The continued availability of comfort care suggests that these surgical procedures are still in transition from experimental technology to standard of care.

Cardiac Surgical Procedures

Acute promyelocytic leukemia. Therapy results and prognostic factors.

From December 1976 to July 1986, 34 patients with acute promyelocytic leukemia (APL) were treated with daunorubicin (DNR) alone and simultaneous supportive therapy with low-dose heparin, platelet transfusions, and fresh frozen plasma. Two consecutive maintenance therapy regimens were employed in patients who achieved complete remission (CR): (1) a classical maintenance with methotrexate and 6-mercaptopurine, with DNR plus methyl-GAG re-inductions; (2) from 1982 an intensive sequential combination therapy regimen was administered. CR was achieved in 23 patients (68%). Only one patient had leukemic resistance. Other failures were a consequence of post-chemotherapy complications. A multivariate logistic regression analysis has been performed to evaluate the prognostic importance on response to remission induction of 25 patient and disease characteristics at diagnosis. The significant variables in decreasing order of significance were: serum albumin level, fever at diagnosis, serum creatinine level, and age. The median duration of remission and survival by Kaplan-Meier analysis were projected to be 24 and 25 months, respectively. Relapses occurred in 11 of 23 CR patients. Nine patients remained in the first remission from 5+ to 37+ months. Short-term (CR) and long-term results (duration of remission and survival) in APL treated for induction with DNR alone were similar to those obtained in other subtypes of acute myeloblastic leukemia by intensive combination chemotherapy.

Adolescent

Sex and diagnostic evaluation of possible coronary artery disease after exercise treadmill testing at one academic teaching center.

Controversy exists as to whether a sex bias exists that affects the diagnostic approach to suspected coronary artery disease: previous studies have used coronary angiography, but not other noninvasive testing, as a primary end point. This investigation examined posttest sex differences in diagnostic evaluation after exercise treadmill testing according to a broader end point than just coronary angiography alone. The design was a cohort analytic study with a 90-day follow-up. The study was done at the Cleveland Clinic Foundation, an academic group practice. Patients included consecutive adults (1023 men and 579 women) with chest pain but no documented coronary disease who were referred for symptom-limited exercise treadmill testing without adjunctive imaging; none had undergone prior invasive cardiac procedures. Main outcome measures included (1) performance of any subsequent diagnostic study (invasive or noninvasive) and (2) performance of coronary angiography as the next diagnostic study. During follow-up, 89 (8.7%) men and 48 (8.3%) women underwent a second diagnostic study (odds ratio 0.95; 95% confidence interval 0.66 to 1.37; p > 0.8), whereas 64 (6.3%) men and 21 (3.6%) women went straight to coronary angiography (odds ratio 0.56; 95% confidence interval 0.34 to 0.93; p = 0.02). In multivariable logistic regression analyses, which considered baseline clinical characteristics, the ST-segment response, and other prognostically important exercise responses, women tended to be less likely than men to be referred to any second test (adjusted odds ratio 0.70; 95% confidence interval 0.42 to 1.19; p > 0.1) but were markedly and significantly less likely to be referred straight to coronary angiography (adjusted odds ratio 0.33; 95% confidence interval 0.17 to 0.65). After exercise treadmill testing, women were only slightly less likely than men to be referred for subsequent diagnostic testing; they were, however, much less likely to be referred straight to coronary angiography as opposed to another noninvasive study.

Academic Medical Centers

Long-term survival following neoadjuvant chemotherapy and radical surgery in locally advanced cervical cancer.

The aim of this study was to analyse the long-term survival and the relationships between prognostic factors at presentation, chemoresponsiveness and disease outcome in patients with locally advanced cervical cancer treated by neoadjuvant chemotherapy and radical surgery (RS). Two consecutive studies of neoadjuvant chemotherapy containing cisplatin, bleomycin plus/minus methotrexate followed by radical hysterectomy and systematic aortic and pelvic lymphadenectomy were carried out between January 1986 and September 1990 on 130 patients with > or = 4 cm stage IB2-III cervical cancer. Survival analysis was performed using the Kaplan and Meier test and Cox's multivariate regression analysis. 128 (98%) of the patients enrolled were evaluable for clinical response and survival, 83% (106) of the patients responded to chemotherapy, with a 15% complete response rate. Logistic regression analysis demonstrated that International Federation of Gynecology and Obstetrics (FIGO) stage, cervical tumour size, parametrial involvement and histotype are highly predictive of response. Responding patients underwent laparotomy, but 8% were not amenable for radical surgery. The 10-year survival estimates were 91%, 80% and 34.5% for stage IB2-IIA bulky, IIB and III, respectively (P < 0.001). After Cox's regression analysis, the parameters significantly associated with survival were the same factors predicting response to neoadjuvant chemotherapy. No stage IB2-IIA bulky patient has so far relapsed, while 12% stage IIB and 56% stage III patients recurred. The 10-year disease-free survival estimates are 91% and 44% for stage IB2-IIB and III, respectively (P < 0.001). Metastatic nodes and persistent tumour in the parametria were the only two independent factors for disease-free survival after multiple regression analysis. After a long-term follow-up (median follow-up 98 months (20-129+)), our results give new evidence of the prognostic value of response to neoadjuvant chemotherapy and of a possible therapeutic benefit of the sequential treatment adopted which, however, must be verified in a randomised setting.

Adult

Prognostic value of B-cell mitogen-induced and spontaneous thymidine uptake in vitro in chronic B-lymphocytic leukaemia cells.

Blood lymphocytes from 50 patients with chronic B-lymphocytic leukaemia (B-CLL) were cultured in vitro with and without the polyclonal B-cell activators (PBA) dextran sulphate (DxS), lipopolysaccharide from E. coli (LPS), and Epstein Barr virus (EBV). Patients with blood lymphocytes that showed a high spontaneous or PBA-induced 3H-thymidine uptake in 4 d cultures had a significantly shorter therapy-free survival than patients whose lymphocytes showed a low thymidine uptake. The DxS-induced cellular thymidine uptake was the most powerful predictor of prognosis. Eighteen patients with leukaemic cells responding to DxS stimulation had a median therapy-free survival of 17 months and a probability of 5 year therapy-free survival of less than 0.1, whereas for 30 patients with DxS unresponsive cells the corresponding figures were greater than 120 months and greater than 0.7, respectively (log rank, P less than 0.0001). A multivariate Cox's regression analysis revealed that the DxS-induced leukaemic cell response was of greater prognostic importance than clinical features such as blood counts and staging according to Rai and Binet. Therefore PBA-induced leukaemic cell thymidine uptake seems valuable in the prediction of prognosis in B-CLL.

Adult

Perceived financial incentives, HMO market penetration, and physicians' practice styles and satisfaction.

OBJECTIVE: To estimate the effects of physicians' personal financial incentives and other measures of involvement with HMOs on three measures of satisfaction and practice style: overall practice satisfaction, the extent to which prior expectations about professional autonomy and the ability to practice good-quality medicine are met, and several specific measures of practice style. DATA SOURCES: A telephone survey conducted in 1997 of 1,549 physicians who were located in the 75 largest Metropolitan Statistical Areas in 1991. Eligible physicians were under age 52, had between 8 and 17 years of post-residency practice experience, and spent at least 20 hours per week in patient care. The response rate was 74 percent. STUDY DESIGN: Multivariate binomial and multinomial ordered logistic regression models were estimated. Independent variables included physicians' self-reported financial incentives, measured by the extent to which their overall financial arrangements created an incentive to either reduce or increase services to patients, the level of HMO penetration in the market, employment setting, medical specialty, exposure to managed care while in medical training, and selected personal characteristics. PRINCIPAL FINDINGS: About 15 percent of survey respondents reported a moderate or strong incentive to reduce services; 70 percent reported a neutral incentive; and 15 percent reported an incentive to increase services. Compared to physicians with a neutral incentive, physicians with an incentive to reduce services were from 1.5 to 3.5 times more likely to be very dissatisfied with their practices and were 0.2 to 0.5 times as likely to report that their expectations regarding professional autonomy and ability to practice good-quality medicine were met. They were also 0.2 to 0.6 times as likely to report having the freedom to care for patients the way they would like along several specific measures of practice style, such as sufficient time with patients, ability to hospitalize, ability to order tests and procedures, and ability to make referrals. These effects were generally reinforced by practicing in an area with a high level of HMO penetration and were offset to some extent by having had exposure to HMOs and the practice of cost-effective medicine while in medical training. CONCLUSIONS: Although financial incentives to reduce services are not widespread, there is a legitimate reason to be concerned about possible adverse affects on the quality of care. More research is needed to investigate directly whether changes in patients' health are affected by their physicians' financial incentives.

Health Maintenance Organizations

A survey screen for prediction of apnea.

Questionnaire data from patients presenting at three sleep disorders centers were used to develop and assess a screening tool for sleep apnea based on the reporting of the frequency of various symptoms of sleep apnea and other sleep disorders plus age, body mass index (BMI) and gender. Patients were not specifically referred for suspicion of sleep apnea. Separate factor analyses of survey responses from 658, 193 and 77 respondents from the first, second and third sites, respectively, each yielded four orthogonal factors, one of which accounted for all the questions concerned with the frequency of disordered breathing during sleep. The survey was shown to be reliable in a subset of patients from one of the sites (test-retest correlation = 0.92). Survey data were then compared to a clinical measure of sleep apnea (respiratory disturbance index) obtained from polysomnography. A multivariable apnea risk index including survey responses, age, gender and BMI was estimated using multiple logistic regression in a total sample of 427 respondents from two of the sites. Predictive ability was assessed using receiver operating characteristic (ROC) curves. The area under the ROC curve was 0.79 (p < 0.0001). For BMI alone, it was 0.73, and for an index measuring the self-report of the frequency of apnea symptoms, it was 0.70. The multivariable apnea risk index has potential utility in clinical settings.

Adult