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PubMed2005

[Quantitative and qualitative investigations of salivary gland function in dependence on irradiation dose and volume for reduction of xerostomia in patients with head-and-neck cancer].

BACKGROUND AND PURPOSE: Radiation treatment of head-and-neck tumors mostly leads to a damage to the salivary glands and a consequential permanent loss of saliva. The aim of this investigation was to establish a modern three-dimensional conformal radiotherapy (3D-CRT) to show a decrease in severe xerostomia in contrast to the proven conventional technique (K-RT) with photons and electrons. PATIENTS AND METHODS: Between April 2002 and September 2003, 32 patients (25 male, seven female, mean age: 58 years) with malignant tumors of the head and neck were included-after surgery or in case of inoperability with curative intent-in a prospective, nonrandomized study. 10/32 patients (31%) received K-RT with photons and electrons, and 22/32 patients (69%) 3D-CRT (six to eight photon portals). The quantity of saliva was measured as stimulated saliva flow rate (ml/5 min) prior to treatment, at the end, and 1, 6, and 12 months after termination of treatment. To find out the resulting mean dose of both parotid glands for every patient in Gray (D(mean) doses), the D(mean) doses of the ipsilateral and the contralateral parotid gland, determined by dose-volume histograms (DVHs), were averaged over. For calculation of the NTCP (normal tissue complication probability), the logistic model was used. RESULTS: In the trend the stimulated salivary flow rates were higher in the group with 3D-CRT than in the group with K-RT during the whole observation period (at 10 weeks after the start of radiotherapy 3D-CRT vs. K-RT with 1.56 +/- 1.6 vs. 0.82 +/- 1.2 ml/5 min; p < 0.1). The patients treated with the K-RT had, on average, significantly higher averaged D(mean) values than those irradiated with 3D-CRT (p < 0.012). Patients, who were irradiated with 3D-CRT for tumors of the larynx or hypopharynx, showed, on average, significantly lower D(mean) values than patients, who were treated with 3D-DRT because of oral cavity or oropharynx carcinomas or with K-RT irrespective of the primary tumor site (p < 0,003). The resulting dose for 50% complication probability (TD(50)) of the salivary glands was 36.9 Gy (30.9-43.5 Gy; 95% confidence interval). The gradient k of the curve located in point TD(50) was 7.7 (4.8-15.8; 95% confidence interval). CONCLUSION: Basically, 3D-CRT seems to be suitable as a standard for all patients with carcinomas of the oral cavity, oro- and hypopharynx. Especially in patients with tumors located in the larynx and hypopharynx, averaged D(mean) doses of both parotids during irradiation can be reached, to conserve salivary flow rates, which are similar to baseline flow rates.

Adult↗
PubMed1995

Peripheral vascular complications in the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I).

OBJECTIVES: In-hospital peripheral vascular complications of balloon angioplasty were compared with those of directional atherectomy in the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I) to identify patients at risk and evaluate costs and outcomes. BACKGROUND: The incidence, costs and outcomes of peripheral vascular complications after coronary intervention have not been fully characterized as a function of randomly assigned therapy. METHODS: At 35 sites in the United States and Europe, 1,012 patients were randomized. Peripheral vascular complications were defined as the composite of pulse loss, pseudoaneurysm, hematoma > 4 cm in diameter or groin hemorrhage necessitating blood transfusion. Logistic models were derived to 1) predict these complications from baseline and procedural characteristics, 2) test the relevance of randomization assignment, and 3) assess their impact on hospital costs and long-term outcomes. RESULTS: Sixty-seven patients (6.6%) developed peripheral vascular complications, of whom 15 (22.4%) required a blood transfusion, 14 (20.9%) underwent vascular surgery, and 2 (3.0%) died. Both in-hospital deaths occurred in patients with peripheral vascular complications. There was no difference in composite peripheral vascular complication rates among patients randomized to angioplasty or atherectomy. Greater age, female gender, postprocedural heparin and intraaortic balloon counterpulsation were predictive of increased risk. In a representative 60% subset, mean hospital costs increased from $9,583 in patients without to $18,350 in those with peripheral vascular complications (p = 0.0001). The unadjusted mortality rate at 1 year was 7.5% for patients with peripheral vascular complications compared with 1.1% for all others (p = 0.0001). These complications identified patients at greater risk of death, myocardial infarction or repeat revascularization at 30 days and 1 year. The atherectomy group had a trend toward more frequent deaths and myocardial infarction. CONCLUSIONS: Directional atherectomy and balloon angioplasty had similar in-hospital peripheral vascular complication rates. Female gender, greater age, postprocedural heparin and intraaortic balloon counterpulsation were predictive of higher risk. The twofold increase in cost and sevenfold increase in long-term deaths highlight the need to prevent these periprocedural events and monitor patients closely.

Angioplasty, Balloon, Coronary↗
PubMed2006

Insights from a national survey into why substance abuse treatment units add prevention and outreach services.

BACKGROUND: Previous studies have found that even limited prevention-related interventions can affect health behaviors such as substance use and risky sex. Substance abuse treatment providers are ideal candidates to provide these services, but typically have little or no financial incentive to do so. The purpose of this study was therefore to explore why some substance abuse treatment units have added new prevention and outreach services. Based on an ecological framework of organizational strategy, three categories of predictors were tested: (1) environmental, (2) unit-level, and (3) unit leadership. RESULTS: A lagged cross-sectional logistic model of 450 outpatient substance abuse treatment units revealed that local per capita income, mental health center affiliation, and clinical supervisors' graduate degrees were positively associated with likelihood of adding prevention-related education and outreach services. Managed care contracts and methadone treatment were negatively associated with addition of these services. No hospital-affiliated agencies added prevention and outreach services during the study period. CONCLUSION: Findings supported the study's ecological perspective on organizational strategy, with factors at environmental, unit, and unit leadership levels associated with additions of prevention and outreach services. Among the significant predictors, ties to managed care payers and unit leadership graduate education emerge as potential leverage points for public policy. In the current sample, units with managed care contracts were less likely to add prevention and outreach services. This is not surprising, given managed care's emphasis on cost control. However, the association with this payment source suggests that public managed care programs might affects prevention and outreach differently through revised incentives. Specifically, government payers could explicitly compensate substance abuse treatment units in managed care contracts for prevention and outreach. The effects of supervisor graduate education on likelihood of adding new prevention and outreach programs suggests that leaders' education can affect organizational strategy. Foundation and government officials may encourage prevention and outreach by funding curricular enhancements to graduate degree programs demonstrating the importance of public goods. Overall, these findings suggest that both money and professional education affect substance abuse treatment unit additions of prevention and outreach services, as well as other factors less amenable to policy intervention.

Community-Institutional Relations↗
PubMed2000

Automated computerized intensive care unit severity of illness measure in the Department of Veterans Affairs: preliminary results. SISVistA Investigators. Scrutiny of ICU Severity Veterans Health Sysyems Technology Architecture.

OBJECTIVE: To evaluate the feasibility of an automated intensive care unit (ICU) risk adjustment tool (acronym: SISVistA) developed by selecting a subset of predictor variables from the Acute Physiology and Chronic Health Evaluation (APACHE) III available in the existing computerized database of the Department of Veterans Affairs (VA) healthcare system and modifying the APACHE diagnostic and comorbidity approach. DESIGN: Retrospective cohort study. SETTING: Six ICUs in three Ohio Veterans Affairs hospitals. PATIENT SELECTION: The first ICU admission of all patients from February 1996 through July 1997. OUTCOME MEASURE: Mortality at hospital discharge. METHODS: The predictor variables, including age, comorbidity, diagnosis, admission source (direct or transfer), and laboratory results (from the +/- 24-hr period surrounding admission), were extracted from computerized VA databases, and APACHE III weights were applied using customized software. The weights of all laboratory variables were added and treated as a single variable in the model. A logistic regression model was fitted to predict the outcome and the model was validated using a boot-strapping technique (1,000 repetitions). MAIN RESULTS: The analysis included all 4,651 eligible cases (442 deaths). The cohort was predominantly male (97.5%) and elderly (63.6 +/- 12.0 yrs). In multivariate analysis, significant predictors of hospital mortality included age (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.04-1.09), comorbidity (OR, 1.11; 95% CI, 1.08-1.15), total laboratory score (OR, 1.07; 95% CI, 1.06-1.08), direct ICU admission (OR, 0.39; 95% CI, 0.31-0.49), and several broad ICU diagnostic categories. The SISVistA model had excellent discrimination and calibration (C statistic = 0.86, goodness-of-fit statistics; p > .20). The area under the receiver operating characteristic curve of the validated model was 0.86. CONCLUSIONS: Using common data elements often found in hospital computer systems, SISVistA predicts hospital mortality among patients in Ohio VA ICUs. This preliminary study supports the development of an automated ICU risk prediction system on a more diverse population.

APACHE↗
PubMed1995

Exploring the role of diet in modifying the effect of known disease determinants: application to risk factors of liver cirrhosis.

The analysis of the combined effects of nutritional factors with other putative disease determinants in log-linear or logistic models is methodologically complicated by the strong multicollinearity between nutritional factors, resulting in poor precision in estimating the parameters. Furthermore, the generally used multiplicative structure is not always the most appropriate for describing the resulting joint effect of two or more factors on the disease risk. The authors addressed such problems in a case-control study assessing the interactions between alcohol intake, chronic hepatitis C virus (HCV) infection, and nutrient intake on the risk of liver cirrhosis. During the period from November 1989 to May 1990, 282 patients admitted to the medical departments of the hospitals of the Province of L'Aquila (central Italy) were enrolled: 115 cirrhotic patients aged 24-82 years (78 of whom were males) hospitalized because of liver decompensation, and 167 control patients aged 25-84 years (100 of whom were males) admitted to the same hospitals for acute diseases unrelated to alcohol intake, infection with hepatotropic viruses, and nutrition. No dose-effect relation was found between the intake of any nutrient and the risk of cirrhosis using classical methods. The analysis of principal components showed, however, that a pattern of higher lipid but lower protein and carbohydrate intakes was significantly associated with the risk of cirrhosis. The Breslow and Storer parametric family of relative risk functions showed that a multiplicative structure was the most adequate to describe the joint effect of nutritional pattern with alcohol intake and/or chronic HCV infection, whereas an additive structure best described the joint effect of chronic HCV infection and alcohol intake. In conclusion, the analysis of principal components and the Breslow and Storer family are useful tools to explore the role of diet on disease risk when precise pathogenic knowledge is not available. As an original finding, the authors suggest that a higher lipid intake, combined with lower protein and carbohydrate intakes, modifies multiplicatively the risk of cirrhosis associated with alcohol intake and/or chronic HCV infection.

Adult↗
PubMed2006

Predictors of response to the 'Coping with Depression' course for older adults. A field study.

This field study explored the prognostic factors of the immediate and long-term effects of the Coping with Depression course for older adults (CWD). With the aim of both indicated as well as secondary prevention, the course is provided by the prevention departments of the community mental health care system in the Netherlands. A total of 317 course participants (age 55-85 years; 69% female) took part in this study; 41% had a major depressive disorder (MDD). A variety of demographic, clinical, psychosocial and treatment factors of possible relevance for indicated and secondary prevention were investigated. Random coefficient regression models and logistic regression models were used to examine their contribution to the immediate and maintenance effect. The course was beneficial for all participants, and the level of depression reached at the end of the course was maintained over the next 14-months. Current MDD, high levels of anxiety, less previous depressive episodes and more education predicted a larger benefit. However, the clinical significance of these predictors was too small to justify further triage. Further treatment should be considered for the participants with a post-treatment score >/=16. Group-membership was not a significant predictor of the variation in effect.

Adaptation, Psychological↗
PubMed2006

Reliability of third molar probing measures and the systemic impact of third molar periodontal pathology.

PURPOSE: This study examined the reliability of assessing clinical periodontal measures on third molars, and the association between oral inflammation with periodontal pathology including third molars, and systemic inflammation including negative obstetric outcomes. PATIENTS AND METHODS: Reliability of third molar probing depth (PD) was assessed for 41 patients by trained examiners. The data for the association between oral inflammation with periodontal pathology and systemic outcomes were derived from an IRB-approved study, "Oral Conditions and Pregnancy." Full mouth periodontal exams including third molars were conducted at less than 24 weeks of pregnancy. Periodontal status, moderate/severe periodontal disease (15 or more sites PD > or =4 mm) was considered as a possible predictor of systemic inflammation and pre-term birth. The upper quartile of the extent of PD for third molars alone (PD > or =4 mm) also was considered as a possible exposure variable for the same outcomes. Chi-square and t tests were used to determine statistical significance (0.05). Significant predictor variables were included in multivariate models. Unconditional logistic multivariate models were used to derive odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Reliability of PD within 1 mm was excellent, and similar for third molars and non-third molars. Data from 1,020 obstetric patients were available for analysis. Eighteen percent of the patients delivered preterm, at less than 37 weeks. Having moderate/severe periodontal disease excluding third molars, was significantly associated with preterm birth (P = .008). Results were more significant if third molars were included (P = .0005). With multivariate models moderate/severe periodontal disease at enrollment including third molar PD, was associated with preterm birth (OR, 1.7; 95% CI, 1.1, 2.6). If only the extent of third molar PD was considered, odds also were increased for preterm birth (OR, 2.4; 95% CI, 1.1, 5.2). If only the extent of third molar PD was considered at enrollment, odds were increased for serum markers of systemic inflammation, elevated serum CRP, and oxidative stress, 8-isoPGF(2alpha). CONCLUSIONS: Dental examiners could reliably assess clinical periodontal measures on third molars. Third molars should be included in studies of systemic outcomes associated with oral inflammation. Women of child-bearing age should be made aware of the systemic risks of oral inflammation with third molar periodontal pathology.

Adult↗
PubMed2005

Medicaid managed care: disparities in the use of thiazolidinediones compared with metformin.

OBJECTIVE: To identify patient characteristics that are associated with the incidence of thiadolidinediones (TZDs) or metformin prescnbing in Medicaid managed care plans. RESEARCH DESIGN AND METHODS: We utilized a retrospective cohort study design. Two-and-one-half years of prescription claims of Medicaid managed care organizations (MCOs) patients who were new utilizers of metformin or TZDs were analyzed using univariate, bivariate and multivariate models. Multivariate logistic regression models were built to assess the combined effect of all variables on the likelihood of incident use of TZDs or metformin. RESULTS: Claims for 3,041 patients were analyzed for the period between January 15, 2000 and June 15, 2002. African Americans and urban residents were less likely to be started on TZDs (OR = 0.678, 95% C1 = 0.830-1.206; OR = 0.579, 95% CI = 0.479-0.699, respectively). Advanced age, preexisting comorbidities and diabetes complications, and prior use of other oral diabetes drugs or insulin were predictors of increased likelihood of TZD initiation. CONCLUSIONS: Race, age, residential setting, preexisting comorbidities and diabetes complications, other oral diabetes drug use, and insulin use are statistically significant predictors of initial prescribing of TZD or metformin in a Medicaid MCO population. Findings can potentially inform the management of diabetes in managed care so as to improve outcomes.

Cohort Studies↗
PubMed2001

Comparison of logistic regression and neural networks to predict rehospitalization in patients with stroke.

CONTEXT: Rehospitalization following inpatient medical rehabilitation has important health and economic implications for patients who have experienced a stroke. OBJECTIVE: Compare logistic regression and neural networks in predicting rehospitalization at 3-6-month follow-up for patients with stroke discharged from medical rehabilitation. DESIGN: The study was retrospective using information from a national database representative of medical rehabilitation patients across the US. SETTING: Information submitted to the Uniform Data System for Medical Rehabilitation from 1997 and 1998 by 167 hospital and rehabilitation facilities from 40 states was examined. PARTICIPANTS: 9584 patient records were included in the sample. The mean age was 70.74 years (SD = 12.87). The sample included 51.6% females and was 77.6% non-Hispanic White with an average length of stay of 21.47 days (SD = 15.47). MAIN OUTCOME MEASURES: Hospital readmission from 80 to 180 days following discharge. RESULTS: Statistically significant variables (P <.05) in the logistic model included sphincter control, self-care ability, age, marital status, ethnicity and length of stay. Area under the ROC curves were 0.68 and 0.74 for logistic regression and neural network analysis, respectively. The Hosmer-Lemeshow goodness-of-fit chi-square was 11.32 (df = 8, P = 0.22) for neural network analysis and 16.33 (df = 8, P = 0.11) for logistic regression. Calibration curves indicated a slightly better fit for the neural network model. CONCLUSION: There was no statistically significant or practical advantage in predicting hospital readmission using neural network analysis in comparison to logistic regression for persons who experienced a stroke and received medical rehabilitation during the period of the study.

Aged↗
PubMed2000

Family dinner and diet quality among older children and adolescents.

CONTEXT: The proportion of children eating dinner with their families declines with age and has decreased over time. Few data exist concerning the nutritional effect of eating family dinner. OBJECTIVE: To examine the associations between frequency of eating dinner with family and measures of diet quality. DESIGN: Cross-sectional. SETTING: A national convenience sample. PARTICIPANTS: There were 8677 girls and 7525 boys in the study, aged 9 to 14 years, who were children of the participants in the ongoing Nurses' Health Study II. MAIN OUTCOME MEASURES: We collected data from a self-administered mailed survey, including food and nutrient intakes from a validated semiquantitative food frequency questionnaire. Main outcome measures included servings per day of selected foods and food groups, daily intakes of selected macronutrients and micronutrients, and frequency of multivitamin use. RESULTS: Approximately 17% of participants ate dinner with members of their family never or some days, 40% on most days, and 43% every day. More than half of the 9-year-olds ate family dinner every day, whereas only about one third of 14-year-olds did so. In age- and sex-adjusted logistic regression models, the odds ratios associated with a frequency of family dinner of most days compared with never or some days, or every day compared with most days, were as follows: for eating at least 5 servings per day of fruits and vegetables, 1.45 (95% confidence interval [CI], 1.37-1.53); for eating any fried foods away from home, 0.67 (95% CI, 0.64-0.70); and for drinking any soda, 0.73 (95% CI, 0.66-0.80). Multiple linear regression showed that an increased frequency of family dinner was also associated with substantially higher intake of several nutrients, including fiber, calcium, folate, iron, vitamins B6, B12, C, and E; lower glycemic load; and lower intake of saturated and trans fat as a percentage of energy. We observed little or no effect on intakes of whole dairy products, red meat, or snack foods. Patterns were similar for boys and girls. CONCLUSIONS: Eating family dinner was associated with healthful dietary intake patterns, including more fruits and vegetables, less fried food and soda, less saturated and trans fat, lower glycemic load, more fiber and micronutrients from food, and no material differences in red meat or snack foods.

Adolescent↗
PubMed1999

Relation of serum ascorbic acid to serum vitamin B12, serum ferritin, and kidney stones in US adults.

BACKGROUND: Concern has been raised that high levels of ascorbic acid consumption may lead to potential adverse effects, such as vitamin B12 deficiency, iron overload, and kidney stones. OBJECTIVE: To examine the relation of serum ascorbic acid level, which reflects intake, to serum vitamin B12 level, serum ferritin level, and kidney stones. METHODS: We analyzed data collected on a random sample of the US population enrolled in the Second National Health and Nutrition Examination Survey, 1976-1980. We analyzed data using linear and logistic regression models. Serum ascorbic acid, serum vitamin B12, hemoglobin, red blood cell mean corpuscular volume (MCV), and serum ferritin levels were measured using standardized protocols. History of kidney stones was determined by self-report. RESULTS: After multivariate adjustment, serum ascorbic acid level was associated with higher serum vitamin B12 levels among women in regression models that assumed a linear relationship; each 57-pmol/L (1.0-mg/dL) increase in serum ascorbic acid level (range, 6-153 micromol/L [0.1 to 2.7 mg/dL]) was independently associated with a serum vitamin B12 level increase of 60 pmol/L (81 pg/ mL) (P<.001). Among men, serum ascorbic acid level was marginally associated with higher serum vitamin B12 levels: each 57-micromol/L (1.0-mg/dL) increase in serum ascorbic acid level was associated with a serum vitamin B12 level increase of 27 pmol/L (36 pg/mL) (P = .10). In addition, serum ascorbic acid level was not associated with correlates of vitamin B12 deficiency, such as higher MCV levels, macrocytosis (MCV >100), or lower hemoglobin concentrations. Serum ascorbic acid level was not independently associated with serum ferritin levels. However, among women only, serum ascorbic acid levels were associated in a nonlinear fashion with prevalence of elevated serum ferritin levels (P = .02). We found no association between serum ascorbic acid level and prevalence of kidney stones in women or men (both P>.05). CONCLUSIONS: Serum ascorbic acid levels were not associated with decreased serum vitamin B12 levels (or indicators of vitamin B12 deficiency), prevalence of kidney stones, serum ferritin levels, or-among men-prevalence of elevated serum ferritin levels. Serum ascorbic acid levels were associated with prevalence of elevated serum ferritin levels among women. Although the clinical relevance of these findings is uncertain, it seems prudent to suggest that women with a genetic susceptibility to iron overload should consider moderating their intake of ascorbic acid.

Adult↗
PubMed2005

Racial treatment trends in localized/regional prostate carcinoma: 1992-1999.

BACKGROUND: African-American men have a greater incidence of and mortality from prostate carcinoma compared with white men, and they are less likely to receive definitive therapy (radical prostatectomy or external beam radiation therapy). During the 1990s, the use of brachytherapy increased; however, its influence on racial and ethnic prostate carcinoma treatment trends remains unclear. The objective of this study was to describe treatment trends over the period 1992-1999 for localized/regional prostate carcinoma among white, Hispanic, and African-American men. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) registry data from 1992 through 1999, logistic regression models were used to determine whether the odds of receiving a specific treatment modality differed by racial and ethnic group and whether the differences changed over time when the models were adjusted for age, marital status, tumor grade, and SEER site (geography). RESULTS: The authors identified 142,340 men, including white men (81.6%), Hispanic men (6.4%), and African-American men (12.0%). Racial and ethnic differences in the rates of use of androgen-deprivation therapy/expectant management were noted; however, these differences appeared to lessen over time (P < 0.001). The rate of utilization of radical prostatectomy increased for Hispanic men, remained flat for African-American men, and decreased for white men. The utilization of brachytherapy and combination therapy increased for all three groups; however, the greatest increase in utilization was among white men. CONCLUSIONS: Further research will be required to determine the patient-level and provider-level variables that influence racial and ethnic treatment differences in localized/regional prostate cancer.

Black or African American↗
PubMed2003

Prevalence of osteoporosis and its reproductive risk factors among Jordanian women: a cross-sectional study.

Extensive differences in the osteoporosis epidemiological pattern among geographic and ethnic groups have been reported. The evidence concerning association of multiple pregnancies, lactations, and other menstrual history factors with low bone mineral density (BMD) remains inconclusive. Previous local studies addressing these issues in Jordan are very restricted. We present a cross-sectional study of Jordanian women who visited outpatient clinics between August 2000 and August 2002 at two community hospitals in Amman City. BMD measurement was performed for all subjects, while comprehensive appraisal of clinical issues related to reproductive status and past medical history was carried out using a structured questionnaire administered to 50% of the subjects. We also attempted to examine the current hypothesis of possible influence of hyperlipidemia and thyroid abnormalities on decreased BMD. According to WHO criteria, 119 (29.6%) were identified as having osteoporosis, 176 (43.8%) were osteopenic, and 107 (26.6%) had normal BMD. The multiple-linear regression analyses at different bone sites revealed that age, years of menopause, low-density lipoprotein (LDL), and follicle-stimulating hormone (FSH) have strong independent associations with decreased BMD at all lumbar and femoral neck regions. The negative effect associated with number of children (live births) and frequency of lactations was only evident at femoral neck. Although years of menstruation, age at menopause, days of menstrual cycle, number of pregnancies, and duration of hormone replacement therapy (HRT) were positively correlated with BMD, they had weaker associations than previous variables. Moreover, in the final multivariable logistic regression model, variables which rendered significantly independent risk factors after adjustment for age and BMI were: current smokers of more that 25 cigarettes/day, postmenopausal women irrespective of HRT use, menopausal years of > or =5 year intervals, natural early menopause, gastrointestinal disease, rheumatoid arthritis, osteoarthritis, hypertension, and thyroid replacement therapy. Ever-lactation, frequent lactation of 4 or more times, duration of lactation interval of 1-6 months and clinical hyperthyroidism were significant protective factors. Hysterectomy with or without oophorectomy, premature ovarian failure, gravidity, menstrual flow pattern, family history of osteoporosis, clinical hypothyroidism, hyperlipidemia, HRT, and corticosteroids therapy were not independent predictors of osteoporosis among our population. It was concluded that the prevalence of this worldwide public health problem among the Jordanian female population is extremely high, and is even found in younger age categories compared to previous international surveys. Though, the number of pregnancies in our multiparous female population showed a negative impact on femoral neck BMD, no evidence of increased risk of osteoporosis among ever-pregnant women was noted. Conversely, the current data analysis highlight many potential risk factors including associated medical illnesses, and other hormonal alterations experienced during menopausal period. Therefore, increased health awareness and intensive screening programs are mandatory for early detection of low bone mass.

Adult↗
PubMed2006

Identification of zinc-ligated cysteine residues based on 13Calpha and 13Cbeta chemical shift data.

Although a significant number of proteins include bound metals as part of their structure, the identification of amino acid residues coordinated to non-paramagnetic metals by NMR remains a challenge. Metal ligands can stabilize the native structure and/or play critical catalytic roles in the underlying biochemistry. An atom's chemical shift is exquisitely sensitive to its electronic environment. Chemical shift data can provide valuable insights into structural features, including metal ligation. In this study, we demonstrate that overlapped 13Cbeta chemical shift distributions of Zn-ligated and non-metal-ligated cysteine residues are largely resolved by the inclusion of the corresponding 13Calpha chemical shift information, together with secondary structural information. We demonstrate this with a bivariate distribution plot, and statistically with a multivariate analysis of variance (MANOVA) and hierarchical logistic regression analysis. Using 287 13Calpha/13Cbeta shift pairs from 79 proteins with known three-dimensional structures, including 86 13Calpha and 13Cbeta shifts for 43 Zn-ligated cysteine residues, along with corresponding oxidation state and secondary structure information, we have built a logistic regression model that distinguishes between oxidized cystines, reduced (non-metal ligated) cysteines, and Zn-ligated cysteines. Classifying cysteines/cystines with a statistical model incorporating all three phenomena resulted in a predictor of Zn ligation with a recall, precision and F-measure of 83.7%, and an accuracy of 95.1%. This model was applied in the analysis of Bacillus subtilis IscU, a protein involved in iron-sulfur cluster assembly. The model predicts that all three cysteines of IscU are metal ligands. We confirmed these results by (i) examining the effect of metal chelation on the NMR spectrum of IscU, and (ii) inductively coupled plasma mass spectrometry analysis. To gain further insight into the frequency of occurrence of non-cysteine Zn ligands, we analyzed the Protein Data Bank and found that 78% of the Zn ligands are histidine and cysteine (with nearly identical frequencies), and 18% are acidic residues aspartate and glutamate.

Bacillus subtilis↗
PubMed1982

Survival models based upon the logistic and log--logistic distributions.

LOGC and LOGLOGC are interactive FORTRAN programs which fit the logistic and log--logistic regression models to censored survival data. Maximum likelihood estimates of parameters and estimates of their standard errors are given together with the corresponding log-likelihood. Survivorship functions, median remaining lifetimes and estimates of confidence intervals for these functions are given. Residual plotting is incorporated to assess the goodness of fit and can be plotted as can the survivorship function and median remaining lifetime estimates together with their corresponding confidence limits.

Computers↗
PubMed1996

Characteristics associated with rapid decline in forced expiratory volume.

Cigarette smoking is known to accelerate decline of pulmonary function; however, the role of other factors is less clear. Characteristics of individuals who experienced rapid decline in forced expiratory volume in 1-sec (FEV1) were examined in 4451 Japanese-American men from the Honolulu Heart Program who were aged 45 to 68 years at baseline (1965-1968) and who produced three acceptable FEV1 measures over a 6-year period. Average annual rates of FEV1 decline were calculated by use of within-person regression and were categorized as rapid (> or = 60 ml/y), moderate (30 to 59 ml/y) or slow (< 30 ml/y). Lifestyle and biologic factors were compared by FEV1 decline categories after adjustment for age. A logistic regression model showed that continued smoking during follow-up, cigarette pack-years, wheezing, coronary heart disease, alcohol intake, and reduced subscapular skinfold were significantly associated with rapid FEV1 decline, after adjustment for age, height, cholesterol, an indicator of Japanese diet, and education. When analyses were restricted to continuous smokers, cigarette pack-years, wheezing, and reduced subscapular skinfold were found to be independent predictors. Among never smokers, lower educational attainment was a predictor of rapid FEV1 decline, and the association involving subscapular skinfold approached significance (P < 0.07). These characteristics may be useful in identifying subgroups of the population who are at increased risk of accelerated decline in pulmonary function and thus would be most likely to benefit from appropriate intervention.

Aged↗
PubMed2005

A national comparison of surgical versus percutaneous drainage of pancreatic pseudocysts: 1997-2001.

Case series results indicate that a surgical approach is superior to percutaneous drainage of pancreatic pseudocysts. To determine if this surgical advantage is persistent, national outcomes for both approaches were compared from 1997 through 2001. The National Inpatient Sample, a 20% sample of all nonfederal hospital discharges, was searched for patients who had a pancreatic pseudocyst diagnosis, an ICD-9 diagnosis code 577.2, and an ICD-9 procedure code of 52.01 for percutaneous drainage (PD) or 52.4 and 52.96 for the surgical approaches. Variables were compared by using either t test or chi2 analysis. Confounding variables were controlled for by linear or logistic regression models. No clinically significant demographic, comorbidity, and disease-specific severity-of-illness differences existed between the two groups. Significant differences in complications, length of stay (15+/-15 versus 21+/-22 days, P<0.0001), and inpatient mortality (5.9% versus 2.8%, P<0.0001) favored the surgical approach. In addition, endoscopic retrograde cholangiopancreatography use had a protective effect on mortality (odds ratio, 0.7), whereas percutaneous drainage had an increased risk of mortality (odds ratio, 1.4). This population-based study suggests that surgical drainage of pancreatic pseudocysts, particularly when coupled with use of endoscopic retrograde cholangiopancreatography, leads to decreased complications, length of stay, and mortality in comparison with percutaneous drainage.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1995

Final height after long-term growth hormone treatment in Turner syndrome. European Study Group.

OBJECTIVES: To study final height after long-term growth hormone (GH) treatment in girls with Turner syndrome (TS). PATIENTS: One hundred fifty three patients with TS, participating in five European trials, were included. They started GH treatment in 1987-1989 at an age of 10 years or older. Mean age at start of treatment ranged between 11.7 and 14.6 years among countries and mean bone age between 9.4 and 11.8 years. Fourteen girls were lost to follow-up, leaving 139 for analysis. Most girls have now attained final height (FH), defined as a linear growth velocity (GV) of 4 mm/yr or less, measured over at least 6 months (group 1, n = 56), or near-FH, defined as a GV of 5 to 9 mm/yr (group 2, n = 22). Sixty-one girls were still growing 10 mm/yr or more. METHODS AND MAIN RESULTS: At the last measurement, mean (SD) height was 150.7 (4.9) cm in group 1 and 148.5 (5.1) cm in group 2. The differences between FH and projected final height based on extrapolation of the initial height-standard deviation score on Turner syndrome reference values, were 2.9 (3.8) and 3.0 (3.3) cm, respectively. The mean gain over the Bayley-Pinneau prediction of FH was 3.3 (3.9) cm in both groups. No significant differences between countries were found. The range of gains over projected height (-4.7 to 12.1 cm) was large, and 25% of gains were 5 cm or more. Gain over initial projection was strongly related to initial growth delay and to growth response during the first 2 years of treatment. A logistic regression model is presented that predicts gain of more than 5 cm with a positive predictive value of 62% and a negative predictive value of 84%. CONCLUSIONS: Long-term GH treatment in girls with TS, starting treatment at a relatively advanced age ( > 10 years) resulted in a modest mean gain in FH of 3 cm, with wide interindividual variation.

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