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Results for “Multivariate response regression”

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PubMed1996

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↗

PubMed1988

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↗

PubMed2000

Perceptions of interethnic group racism predict increased vascular reactivity to a laboratory challenge in college women.

African-Americans have disproportionately higher rates of hypertension than any other U.S. ethnic group. Researchers have postulated that the psychosocial-stress association with racism may help explain these higher rates in African-Americans, as well as blood pressure variability among African-Americans. Using a quasi-experimental design, this study examined the relationship between perceived interethnic group racism (racism) and blood pressure responses in 39 African-American females. Measurements of blood pressure were obtained before, during, and after a laboratory challenge where participants spoke about their personal views and feelings concerning animal rights. Perceptions of racism, as well as psychological and coping responses to racism, were assessed via the Perceived Racism Scale. The results revealed that on average, participants perceived racism 75.25 times/year. Racist statements were perceived most often, and speaking up was the most frequently reported coping response. The overwhelming majority of participants (76.47%) used active and passive coping responses to deal with racism. Among the psychological responses to racism, the magnitude of emotional responding was greatest for anger. Multivariate regression analyses indicated that perceived racism was significantly and positively related to diastolic blood pressure changes during the speech (p = .01), early recovery (p < .003), and late recovery (p = .01) periods. Potential confounders did not mitigate these effects. The findings highlight the importance of delineating the role of more real-world behavioral challenges in future research exploring blood pressure variability and hypertension risk in African-Americans.

Adaptation, Psychological↗

PubMed2005

Therapeutic thresholds in methadone maintenance treatment: a receiver operating characteristic analysis.

Twenty-four-hour trough (R)- and (R,S)-methadone plasma concentrations were measured on 94 methadone maintenance treatment (MMT) patients classified as 'responders' or 'non-responders', based on urine toxicology evidence of recent illicit opiate use. Receiver operating characteristic (ROC) curves for daily dose, dose/bodyweight, and (R)- and (R,S)-methadone trough plasma concentrations were used to identify optimal thresholds; areas under the curve (AUC) were used to compare predictive power. Non-responders (n=37) had a lower mean dose (73 mg/day versus 147 mg/day; p<0.001), (R)-methadone concentration (136 ng/ml versus 223 ng/ml; p<0.005) and (R,S)-methadone concentration (266 ng/ml versus 409 ng/ml; p=0.001) than responders. On multivariate regression, duration of treatment and methadone dose were significantly associated with treatment response. After backward stepwise regression, each year of treatment increased the odds of abstinence from illicit opioid use by 34% (OR 1.34; 95% CI 1.14-1.57)); each 20mg of methadone dose by 36% (OR 1.36 CI; 95% CI 1.11-1.67). On ROC analysis, AUC for daily dose (0.77, 95% CI 0.68-0.87), dose/bodyweight (0.76, 95% CI 0.66-0.85), (R)-methadone (0.73, 95% CI 0.63-0.84) and (R,S)-methadone concentration (0.70, 95% CI 0.59-0.81) did not differ significantly. Dose/bodyweight, and trough plasma concentrations of (R)- or (R,S)-methadone were no better predictors of treatment response than daily dose, and did not improve the fit of the model for treatment outcome as judged by the likelihood ratio test (p=0.21, 0.88, and 0.97, respectively). Optimal therapeutic thresholds (sensitivity, specificity) were: daily dose 100mg/day (67%, 81%); (R)-methadone 200 ng/ml (51%, 78%); (R,S)-methadone 400 ng/ml (40%, 81%). Thresholds with specificity near 90% (dose 140 mg/day; (R)-methadone 250 ng/ml; (R,S)-methadone 500 ng/ml) may help guide dose titration for patients continuing to use illicit opiates.

Adult↗

PubMed1997

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↗

PubMed1998

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↗

PubMed2001

Reduced expression of BAX is associated with poor prognosis in patients with epithelial ovarian cancer: a multifactorial analysis of TP53, p21, BAX and BCL-2.

Traditional clinicopathological features do not predict which patients will develop chemotherapy resistance. The TP53 gene is frequently altered in ovarian cancer but its prognostic implications are controversial. Little is known on the impact of TP53-downstream genes on prognosis. Using molecular and immunohistochemical analyses we examined TP53 and its downstream genes p21, BAX and BCL-2 in ovarian tumour tissues and have evaluated the results in relation to clinico-pathological parameters, clinical outcome and response to platinum-based chemotherapy. Associations of tested factors and patient and tumour characteristics were studied by Spearman rank correlation and Pearsons chi2 test. The Cox proportional hazard model was used for univariate and multivariate analysis. The associations of tested factors with response was tested using logistic regression analysis. TP53 mutation, p21 and BCL-2 expression were not associated with increased rates of progression and death. Expression of TP53 was associated with a shorter overall survival only (relative hazard rate [RHR] 2.01, P = 0.03). Interestingly, when combining TP53 mutation and expression data, this resulted in an increased association with overall survival (P = 0.008). BAX expression was found to be associated with both progression-free (RHR 0.44, P = 0.05) and overall survival (RHR 0.42, P = 0.03). Those patients who simultaneously expressed BAX and BCL-2 had a longer progression-free and overall survival compared to patients whose tumours did not express BCL-2 (P = 0.05 and 0.015 respectively). No relations were observed between tested factors and response to platinum-based chemotherapy. We conclude that BAX expression may represent a prognostic indicator for patients with ovarian cancer and that the combined evaluation of BAX and BCL-2 may provide additional prognostic significance.

Adult↗

PubMed2006

An outbreak of gastrointestinal illness and erythema nodosum from grated carrots contaminated with Yersinia pseudotuberculosis.

BACKGROUND: Outbreaks of Yersinia pseudotuberculosis infection have been epidemiologically linked to fresh produce, but the bacterium has not been recovered from the food items implicated. In May 2003, a cluster of gastrointestinal illness and erythema nodosum was detected among schoolchildren who had eaten lunches prepared by the same institutional kitchen. METHODS: We conducted a case-control study and trace-back, environmental, and laboratory investigations. Case patients had culture-confirmed Y. pseudotuberculosis O:1 infection, erythema nodosum, or reactive arthritis. Bacterial isolates from clinical and environmental samples were compared using pulsed-field gel electrophoresis (PFGE). RESULTS: Of 7392 persons at risk, 111 (1.5%) met the case definition; 76 case patients and 172 healthy control subjects were enrolled in the case-control study. Only raw grated carrots were significantly associated with illness in a logistic-regression model (multivariable odds ratio, 5.7 [95% confidence interval, 1.7-19.5]); a dose response was found for increasing amount of consumption. Y. pseudotuberculosis O:1 isolates from 39 stool specimens and from 5 (42%) of 12 soil samples that contained carrot residue and were obtained from peeling and washing equipment at the production farm were indistinguishable by PFGE. CONCLUSIONS: Carrots contaminated early in the production process caused a large point-source outbreak. Our findings enable the development of evidence-based strategies to prevent outbreaks of this emerging foodborne pathogen.

Adolescent↗

PubMed1985

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↗

PubMed2003

Effects of recombinant human insulin-like growth factor (IGF)-I and estrogen administration on IGF-I, IGF binding protein (IGFBP)-2, and IGFBP-3 in anorexia nervosa: a randomized-controlled study.

Administration of recombinant human (rh) IGF-I has been shown to have positive effects on bone density in anorexia nervosa, but the effects of rhIGF-I and estrogen on IGF binding protein (IGFBP)-2 and IGFBP-3 in anorexia nervosa are not known. Sixty-five osteopenic women with anorexia nervosa were randomized to rhIGF-I (30 micro g/kg sc twice daily) alone (n = 15), daily ethinyl estradiol (Ovcon 35) with rhIGF-I (n = 15), estradiol and placebo (n = 15), or placebo (n = 14) for 9 months. Subjects were 25.6 +/- 0.8 yr of age, low weight (body mass index 16.6 +/- 0.2 kg/m(2)) and osteopenic (T scores -2.06 +/- 0.09 for spine and -1.76 +/- 0.13 for hip). IGFBP-3 correlated with total hip bone density (r = 0.47, P = 0.0002) and was a significant predictor of hip bone density (P = 0.010) independent of IGF-I and body mass index in a multivariate regression model. During therapy, IGFBP-2 increased by 48 +/- 19 ng/ml in response to rhIGF-I and decreased by -38 +/- 22 ng/ml in response to placebo (P = 0.011). IGFBP-3 decreased (-895 +/- 120 ng/ml) in response to rhIGF-I but showed a minimal change (-53 +/- 99 ng/ml) in response to placebo (P < 0.0001). In contrast, no significant effect of estrogen was seen on IGF-I, IGFBP-2 or IGFBP-3. Among patients receiving rhIGF-I, the change in IGFBP-2 was inversely associated with the change in total hip bone density (R = -0.47, P = 0.013). In conclusion, our data suggest that chronic rhIGF-I administration increases IGF-I and IGFBP-2 and decreases IGFBP-3 in women with anorexia nervosa. IGFBP-2 and IGFBP-3 may be important determinants of bone density in this population.

Adolescent↗

PubMed2004

[Factors associated with precarious prenatal care in a sample of post-partum adolescent mothers in maternity hospitals in Rio de Janeiro, Brazil, 1999-2000].

This study characterizes the women receiving precarious prenatal care according to socio-demographic variables, mother's reproductive history, family support, satisfaction with pregnancy, and risk behavior during pregnancy. A total of 1,967 adolescents were interviewed in the immediate post-partum in public and outsourced maternity hospitals in the City of Rio de Janeiro. The dependent variable was the number of prenatal appointments (0-3; 4-6; 7 or more). The statistical analysis aimed to test the hypothesis of homogeneity of proportions, including bi- and multivariate analysis, using multinomial logistic regression, in which the reference category for the response variable was 7 or more prenatal visits. Higher (and statistically significant) proportions of insufficient number of prenatal visits (0-3) were associated with: precarious sanitation conditions; not living with the child's father; attempted abortion; and smoking, drinking, and/or drug use during pregnancy. The results strongly indicate that mothers with worse living conditions and risk behavior during pregnancy were the same who lacked access to prenatal care.

Adolescent↗

PubMed1999

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↗

PubMed2001

Infection and disease among household contacts of patients with multidrug-resistant tuberculosis.

SETTING: Urban public teaching and referral hospital in Espirito Santo, Brazil. OBJECTIVE: To assess whether rates of infection and progression to active tuberculosis (TB) differed between household contacts of patients with multidrug-resistant (MDR) and drug susceptible (DS) pulmonary tuberculosis. DESIGN: Household contacts were assessed for evidence of TB infection and disease by purified protein derivative (PPD) skin testing, physical examination, chest X-ray, and sputum smear and culture. RESULTS: Among 133 close contacts of patients with MDR-TB, 44% were PPD-positive (> or =10 mm) compared to 37% of 231 contacts of the DS-TB cases (P = 0.18, chi2 test, OR 1.2, 95%CI 0.8-2). In a multivariate logistic regression analysis, after allowance for between-household variation in PPD responses, PPD positivity among household contacts of patients with MDR-TB remained comparable to PPD positivity in contacts of patients with DS-TB (OR 2.1, 95%CI 0.7-6.5). Respectively six (4%) and 11 (4%) contacts of the MDR- and DS-TB cases were found to have active TB at the time of initial evaluation or during follow-up (P = 0.78, chi2 test). Five of six contacts of MDR-TB cases and nine of nine contacts of DS-TB cases who developed TB, and for whom drug susceptibility test results were available, had the same bacterial susceptibility profiles as their index cases. DNA fingerprinting analysis of Mycobacterium tuberculosis isolates was identical between household contacts with active TB and the index MDR or DS-TB case for all 14 pairs compared. CONCLUSION: Our data suggest that the prevalence of tuberculous infection and progression to active TB among household contacts exposed to DS and MDR-TB cases is comparable, despite a longer duration of exposure of contacts to the index case in patients with MDR-TB.

Adolescent↗

PubMed2006

Early television viewing is associated with protesting turning off the television at age 6.

BACKGROUND: The effects of early exposure to television remain poorly defined. Although some have speculated that television may be habit-forming, evidence is lacking especially in young children. OBJECTIVE: To test the hypothesis that television viewing in the first 4 years of life is associated with protesting having the television turned off at age 6. METHODS: We used data from the National Longitudinal Survey of Youth. Parents reported how much television their children watched before the age of 4. They also reported how often their children protested having the television turned off at age 6. Their responses to this question were dichotomized to almost never vs other. Multivariate logistic regression was used to test the independent association of early television watching with subsequent protest at turning off the television, controlling for externalizing behavior scores at age 6, parenting style, and other covariates. RESULTS: Data were available for 1331 children. Sixty-three percent of children protested having the television turned off at age 6. In a logistic regression model, hours of television viewed per day before age 4 was associated with increased odds of protesting at age 6 (1.08 [1.02-1.15]). CONCLUSION: Early television exposure is associated with resistance to turning off the television at school age.

Age Factors↗

PubMed2006

Electrocardiographic abnormality for workers exposed to carbon disulfide at a viscose rayon plant.

OBJECTIVE: This study investigated electrocardiography (ECG) manifestations for male workers with carbon disulfide exposure at rayon manufacturing plants. METHODS: A total of 251 men in the exposure group and 226 administrative clerks in the reference group received physical examinations and completed questionnaires. RESULTS: The prevalence of ECG abnormalities was much higher in the carbon disulfide exposure group (25.9%, n = 65) than in the reference group (2.7%, n = 6), with an odds ratio (OR) of 12.8 (95% confidence interval [CI] = 5.4-30.2). The foremen were at the highest risk of abnormal ECG (OR = 20.6, 95% CI = 6.5-65.2), followed by filament-spinning workers (OR = 14.2, 95% CI = 5.7-35.3), viscose-manufacturing workers (OR = 11.3, 95% CI = 4.3-30.1), and carbon disulfide-manufacturing workers (OR = 8.1, 95% CI = 2.7-25.6). The multivariate logistic regression analysis based on cumulative exposure index also showed a dose-response relationship with the exposure, and the risk of ECG abnormality could be initiated at the exposure history of 31 to 57 year-ppm with an OR of 7.2 (95% CI = 1.5-36.7). CONCLUSIONS: In general, the ECG abnormalities observed in workers at the permissible exposure level of carbon disulfide implicate the importance of environmental control of the chemical and of workers' education in exposure prevention at work.

Adult↗

PubMed2003

Hemoglobin as an independent prognostic factor in the radiotherapy of head and neck tumors.

PURPOSE: The purpose of this study was to analyze the prognostic value of baseline hemoglobin levels before radiotherapy in patients with head and neck tumors. PATIENTS AND METHODS: In a retrospective study with a median follow-up of 43 months, we analyzed the results of 214 patients irradiated for head and neck cancer between January 1, 1990 and January 1, 1998 (180 men and 34 women; median age 58 years). The treatment concept consisted in adjuvant radiotherapy in 58 patients, 77 patients received definitive radiochemotherapy, 42 patients definitive radiotherapy, and 37 patients reirradiation for in-field recurrence. Baseline hemoglobin values were divided in four groups of the same patient number (quartiles). Several known prognostic factors like sex, age, tumor stage, histologic grading, performance status, and treatment scheme were analyzed for their influence on overall and event-free survival and correlated with pretreatment hemoglobin values (Kaplan-Meier method). In addition, univariate und multivariate logistic regression analyses were carried out to evaluate the effect of baseline hemoglobin on response rates. RESULTS: The median survival (event-free survival) of all patients amounted to 15 months (10 months). 25%, 50%, and 75% of patients had hemoglobin values < 11.2 g/dl, < 12.7 g/dl, and < 13.9 g/dl, respectively. In the univariate analysis, the following variables were significant prognostic factors for overall/event-free survival (log-rank test): treatment concept (p < 0.001/p < 0.001), tumor stage (p < 0.001/p < 0.001), general condition (p < 0.001/p < 0.001), and pretreatment hemoglobin (p = 0.014/p = 0.05). Multivariate analysis (Cox) proved these parameters to be independent of each other. In addition, response rate after radiation showed a strong association between hemoglobin and local control probability (p = 0.02). CONCLUSION: In this retrospective analysis, baseline hemoglobin level was shown to be an independent significant prognostic factor in radiotherapy of head and neck cancer patients. Therefore, the value of tumor anemia as a prognostic factor should be emphasized more.

Adult↗

PubMed1995

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↗

PubMed1999

Integrated approach to prediction of cervical intra-epithelial neoplasia status through a case-control study.

A case-control study on cervical intra-epithelial neoplasia (CIN) was carried out on 398 subjects in the state of West Bengal, India. These samples were taken from mass screening programs organized by the authors, maintaining the uniformity of sampling to the extent possible. The cervical smears were tested by the Papanicolaou (PAP) method, following the Bethesda system for reporting of CIN status. Odds ratios and correlation coefficients among different variables, assumed to produce carcinoma of the cervix, show that 6 out of 11 variables, i.e., age, education, socio-economic status, duration of marriage, age at marriage and body surface, are associated with CIN. Multivariate analysis of logistic regression was carried out using BMDP-LR with dichotomized response variables considering CIN (0 and 1) in one group and CIN (2 and 3) in the other group. The outcome of the analysis indicated that age and educational level are 2 contributing factors for CIN. The percentage of correct classification in this analysis has improved to 74.5%, with a probability of 0.90. Polychotomous regression analysis was carried out using BMDP-PR in the next step. This analysis showed that parity was a contributing factor, in addition to age and educational level. These 3 factors provide a predictive model for identifying the high-risk group in a rational way. This approach would restrict screening to approximately 10% of the population. Subsequently, the model has been validated in a confirmatory trial among 85 new cases and was found to work satisfactorily.

Adult↗