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PubMed1999

Cognitive predictors of resistiveness in dementia patients.

Resistiveness to physical care among patients with dementia is a common and burdensome problem. Forty-nine nursing home residents with dementia were administered the Mini-Mental State Exam (MMSE) and the Royall Executive Interview (EXIT), a specific test of frontal-subcortical function. Nurses rated resistiveness on every shift for 3 days. Correlation with resistiveness ratings was stronger for the EXIT (r=0. 73) than for the MMSE (r=-0. 46); logistic modeling found the EXIT to be a strong independent predictor of resistiveness. Executive dysfunction as measured by the EXIT is a major determinant of resistiveness to care in long-term care residents with dementia, possibly as a result of such patients' tendency toward inertia.

Aged↗

PubMed1994

Effects of handling and transport on bruising of sheep sent directly from farms to slaughter.

The bruising of sheep carcases results in economic losses to the meat industry and is one indicator of welfare problems before slaughter. In this study the numbers of potentially bruising events and the transport conditions of sheep taken directly from farms to a slaughterhouse were related to the occurrence of bruising. Among 2509 sheep in 79 groups the mean number of potentially bruising events was 0.71 per sheep, and they were due mainly to riding behaviour and wool-pulls which occurred most commonly while they were being handled before being stunned. The mean proportion of bruised carcases per group was 0.25, and there was a mean of 0.31 bruises per sheep. Most bruises occurred on the back and were bright red and between 2 and 4 cm in diameter. The mean space allowance per animal on the vehicles was 0.29 m2 and the mean journey time was 251 minutes. A logistic model was used to examine the effects of seven variables on the risk of bruising. More space per animal, transport on the lower deck or at the front of the vehicle, and increased handling all increased the risk of bruising. There were some significant correlations between potentially bruising events and bruising on specific parts of the body.

Abattoirs↗

PubMed2004

Cytochrome P450 1A1 polymorphism and childhood leukemia: an analysis of matched pairs case-control genotype data.

The association between the genotypic frequencies of the cytochrome P450 1A1 polymorphism and the risk of childhood leukemia is explored with the data from a matched case-control study. The data are displayed in a 3 x 3 case-control array, and the discordant pair counts are assessed for quasi-independence, homogeneity, and symmetry. This statistical approach is contrasted to the more typical analysis of matched data based on a conditional logistic model and estimated odds ratios. The statistical analysis of 175 matched pairs (part of a large study of potential environmental/genetic influences on the risk of childhood leukemia) showed no evidence of an association between cytochrome P450 1A1 genotype frequencies and case-control status.

Age Distribution↗

PubMed1993

[Multiple pregnancy risk factors in medically assisted reproduction].

FIVNAT registry collected 4,323 clinical pregnancies from 1987 to 1991, and allowed us to analyse the risk factors for multiple pregnancies. The multiple pregnancy rate is around 28%, 23% for twin pregnancies and 5% for triplet pregnancies. The number of transferred embryos is not the only factor to be significantly related with the risk of multiple pregnancy: male infertilities, cleavage rate over 50%, and women's age (at young ages multiple pregnancy rate are higher) are also significant. A multivariate logistic model was applied to analyse the relative part of these different factors. We also estimated the success rate and the multiple pregnancy rate which should have been obtained if the number of transferred embryos has been limited, in order to reduce the multiple pregnancy rate to 3%.

Adult↗

PubMed2004

Oral health and its determinants among Mongolian dentists.

This study compares the dental health of dentists with that of their population counterparts, and relates dentists' oral health to oral health behavior and professional preventive knowledge and orientation. A questionnaire requesting information on the dentists' oral health, preventive knowledge, and orientation and oral health behavior, was targeted at all actively practicing dentists (n = 250) in the Mongolian capital of Ulaanbaatar. A self-reported dentigram served as the basis for assessing dental health, while the 1996 National Oral Health Survey provided data for comparison with population counterparts. The response rate was 98%. Compared to their general-population counterparts, younger dentists exhibited a similar level of caries experience (DMFT) and missing teeth (NMT), whereas older dentists exhibited a lower level. In all age groups, mean numbers of decayed teeth (DT) among dentists were much smaller than for their population counterparts, whereas mean numbers of filled teeth (FT) were much higher. Of all, 81% reported brushing their teeth twice daily or more, 62% used fluoride-containing toothpaste always or almost always, and 52% consumed sugar-containing foods between main meals less than once a day. The better oral health behavior of dentists was best explained by their greater preventive knowledge and their better dental health by better oral health behavior in logistic models. It is concluded that among these dentists there is room for improvement of their own oral health behavior. Towards this end, specially designed continuing education courses could serve to improve dentists' health-related knowledge and change their oral self-care behavior.

Adult↗

PubMed1992

The relation between multiple births and maternal risk of breast cancer.

Data from two case-control studies conducted in New York State during 1982-1986 were used to examine the relation between multiple births and the maternal risk of breast cancer. The cases were 2,561 women between 20 and 79 years of age with a diagnosis of primary breast cancer. Controls (n = 2,616) were selected from driver's license files and matched to cases by year of birth and county of residence. The odds ratio for any multiple birth was 0.94 (95% confidence interval (CI) 0.56-1.56) in women less than 55 years of age and 0.95 (95% CI 0.62-1.46) in women aged 55-79 years. A previous study had shown a multiple last birth to be protective against breast cancer in women less than 55 years of age (odds ratio (OR) = 0.60, 95% CI 0.43-0.85). A decreased risk of breast cancer was also observed for this age group in the present study, but the magnitude of the effect was not as strong and the confidence interval included unity (OR = 0.85, 95% CI 0.43-1.68). A logistic model that controlled for age at first pregnancy, number of live births, age, and county of residence increased the odds ratio to 0.97 for a multiple last birth. The current study does not support an association between multiple births and maternal risk of breast cancer.

Adult↗

PubMed1994

Prediction of event-free survival after hospital discharge in acute myocardial infarction treated with tissue-plasminogen activator.

The incidence of recurrent ischemia, congestive heart failure and death during the first year after discharge were analysed prospectively in a group of 312 patients randomized double blindly to rt-PA (n = 156) or placebo within 5 hours after the onset of acute myocardial infarction. The in-hospital mortality was 4.4% in the rt-PA and 6.4% in the placebo group; the total-mortality after a follow-up of 16 months was respectively 7.6 and 9.6%. During 16 months follow-up reinfarction occurred in 5.4% of the rt-PA treated patients versus 0.0% in controls (p = 0.004). Revascularization was required in 17% of the population (24% in rt-PA versus 16% in controls, N.S.), angina at rest and congestive heart failure, demanding hospitalization developed in 5.1% of the patients (5.3% in rt-PA versus 4.7% in controls, N.S.) and 3.4% of the patients in each group died after discharge. A logistic model constructed to predict event-free survival showed that enzymatic infarct size, exercise capacity and the hemodynamic response at a predischarge bicycle exercise test and end-systolic volume at 2 weeks were predictors of new events. Considerable overlapping between patients with and without a new event was observed.

Double-Blind Method↗

PubMed2005

Neonatal antecedents for cerebral palsy in extremely preterm babies and interaction with maternal factors.

BACKGROUND: Preterm delivery is associated with an increased risk of cerebral palsy (CP). The greatest risk is for infants born <28 weeks' gestation. AIMS: To identify significant neonatal risk factors for CP and explore the interactions between antenatal and neonatal risk factors, among extremely preterm infants of 27 weeks' gestation or less. STUDY DESIGN: Nested case control design. METHODS: Infants born between 1989 and 1996, at 24-27 weeks' gestation, were evaluated: 30 with CP at 2 years corrected age and 120 control infants matched for gestation age. Neonatal variables were compared using matched analyses with the interaction between antenatal and neonatal factors being examined using logistic regression analyses. RESULTS: Risk factors for CP on matched analyses included patent ductus arteriosus requiring surgical ligation, peri-intraventricular haemorrhage, moderate to severe ventricular dilatation, periventricular leukomalacia (PVL) and need for home oxygen. Independent neonatal predictors were ventricular dilatation (OR 7.3; 95% CI 1.6, 32.3), PVL (OR 29.8; 95% CI 5.6, 159.1) and home oxygen use (OR 3.4; 95% CI 1.2, 9.4). No interaction terms in the logistic models were significant between the previously identified pregnancy risk factors of absence of antenatal steroids and intrauterine growth restriction and the neonatal risk factors. CONCLUSIONS: PVL is the most powerful independent predictor of CP in extremely preterm infants of 27 weeks' gestation or less and appears to be uninfluenced by antenatal factors.

Cerebral Palsy↗

PubMed1998

Relationship between the level of activities of daily living and chronic medical conditions among the elderly.

The purpose of this study is to observe the disease-disability association through a cross-sectional study. Between 1994 and 1995, we conducted a questionnaire survey in 5 towns in Japan. Among the items included in the questionnaire, 5 related to ADL (bathing, feeding, dressing/undressing, toileting, and going out socially) were treated as purpose variables; and 5 related to the history of medical treatment received over the past year (diabetes, heart disease, cerebrovascular disease, neuralgia, and bone fractures) were used as explanatory variables. Multiple logistic models were applied to observe the relationship. The history of medical treatment for cerebrovascular disease greatly and unavoidably affects disability related to ADL. Bone fractures, diabetes, and heart diseases contributed to specific ADL disabilities.

Activities of Daily Living↗

PubMed1998

Occupational role performance in persons with back pain.

PURPOSE: Back pain is a major cause of work disability but there is little data on the impact of back pain among persons who are working. The purpose of this study was to develop a measure of occupational role performance for individuals with back pain and to examine its relationship with sociodemographic and work-related factors. METHOD: Item analysis and reduction resulted in a short, eight-item Occupational Role Questionnaire (ORQ) consisting of two scales, a productivity scale and a satisfaction with work scale. The scales had good internal consistency and correlated as expected with the Roland and Morris Disability Scale. RESULTS: In a multivariate logistic model, significant negative effects on work satisfaction were observed for age 30-39 years relative to age 50+, having a job that required lifting, and the level of disability. CONCLUSION: The ORQ may have applications in studying the consequences of back pain and other chronic conditions in the workplace.

Adult↗

PubMed2002

[Study on genetic epidemiology of nasopharyngeal carcinoma in Guangdong, China].

OBJECTIVE: To explore the characteristic of genetic epidemiology of nasopharyngeal carcinoma (NPC) in a high risk area Guangdong province, China. METHODS: Population investigation was made on the nuclear pedigrees of the first patient with NPC and his/her spouse, and then complex segregation analysis was performed using regressive Logistic model. RESULTS: The risk of suffering from NPC is 9.31 times higher in the first degree relatives of patient with NPC than in the first degree relatives of spouse. The separation ratio and heritability are 0.0588 (0.0182, 0.0994) and 68.08% respectively. The result of complex segregation analysis shows that model D is better than model A. CONCLUSION: The genetic trend and familial clustering of NPC are more significant and powerful in Guangdong. The risk of suffering from NPC is related with parent's state and senior sibling's state. Nasopharyngeal carcinoma is a multi-gene hereditary disease, but a single gene that decides the susceptibility to NPC may be present.

Adult↗

PubMed2005

Dynamics of early childhood overweight.

OBJECTIVE: To study the dynamic processes that drive development of childhood overweight by examining the effects of prenatal characteristics and early-life feeding (breastfeeding versus bottle feeding) on weight states through age 7 years. We test a model to determine whether prenatal characteristics and early-life feeding influence the development of a persistent early tendency toward overweight and/or whether prenatal characteristics and early-life feeding factors influence the likelihood that children will change weight states as they get older. METHODS: Data from the National Longitudinal Survey of Youth's Child-Mother file were used to implement these analyses. A total of 3022 children were included in this sample. For inclusion in this sample, valid information on height and weight during 3 consecutive interviews when the child was aged 24 to 95 months as well as valid data on prenatal and birth characteristics were needed. The primary outcome measure was childhood overweight (BMI >95th percentile). Multivariate logistic models and first-order Markov models were estimated. RESULTS: Early development of childhood overweight was associated with race, ethnicity, maternal prepregnancy obesity, maternal smoking during pregnancy, and later birth years. In later years, the factor that contributed the most to being overweight was having been overweight in the previous observation period. However, with conditioning on the child's having been overweight in the previous observation period, the prenatal factors that contributed to early childhood overweight, except for birth cohort, were also associated with development of overweight among children who had previously been normal weight and perpetuated the persistence of overweight over time. CONCLUSIONS: This research suggests that prenatal characteristics, particularly race, ethnicity, maternal smoking during pregnancy, and maternal prepregnancy obesity, exert influence on the child's weight states through an early tendency toward overweight, which then is perpetuated as the child ages. These findings are intriguing as they provide additional clues to the genesis of childhood overweight and suggest that overweight prevention may need to begin before pregnancy and in early childhood.

Child↗

PubMed2005

Tests of trait-haplotype association when linkage phase is ambiguous, appropriate for matched case-control and cohort studies with competing risks.

The impact of competing risks on tests of association between disease and haplotypes has been largely ignored. We consider situations in which linkage phase is ambiguous and show that tests for disease-haplotype association can lead to rejection of the null hypothesis, even when true, with more than the nominal 5 per cent frequency. This problem tends to occur if a haplotype is associated with overall mortality, even if the haplotype is not associated with disease risk. A small simulation study illustrates the magnitude of bias (high type I error rate) in the context of a cohort study in which a modest number of disease cases (about 350) occur over time. The bias remains even if the score test is based on a logistic model that includes age as a covariate. For cohort studies, we propose a new test based on a modification of the proportional hazards model and for case-control studies, a test based on a conditional likelihood that have the correct size under the null even in the presence of competing risks, and that can be used when haplotype is ambiguous.

Aged↗

PubMed1990

Prevalence of Raynaud phenomenon in the adult population of South Carolina.

A prevalence estimate for Raynaud phenomenon among adult residents of South Carolina was based on data obtained from respondents in a statewide health survey, followed by face-to-face interviews and clinical screening for Raynaud phenomenon, using a screening procedure developed by the authors. The survey obtained 5246 personal interviews from a probability sample of over 3000 households, and 494 survey subjects participated in the clinical screening. The prevalence estimates and their standard errors were computed using survey case weights, design-based estimation, and logistic modelling techniques. The prevalence of Raynaud phenomenon among adult residents of South Carolina was determined to be 3.5%, with a standard error of 0.6%. Prevalence was higher for females (4.3%, SE = 0.7%) than for males (2.7%, SE = 0.6%). These figures are much lower than most estimates in the existing literature on Raynaud phenomenon.

Adult↗

PubMed2003

Reliability of clinical parameters for predicting the outcome of oral malodor treatment.

We conducted the present study to determine which clinical parameters for diagnosing halitosis are most reliable in the development of an accurate prognosis for oral malodor treatment. Clinical evaluation included a questionnaire, oral examination and volatile sulfur compounds (VSC) measurement, and organoleptic test (OLT) at baseline. Ninety-two patients classified with oral pathologic halitosis were treated in a similar manner. Improved treatment outcome was defined as < 0.25 ppm of total VSC, < or = 2 OLT score, and < 30 on the "sad feeling" scale as subjective stress level by oral malodor 6 months after baseline. Thirty-four patients demonstrated improvement due to the treatment. In a multiple logistic model, pocket depth, OLT score, intra-oral discomfort, and self-perception of oral malodor at baseline displayed significant association with "not improved outcome". These results suggest that malodor- and periodontal-disease-related parameters and self-estimation of malodor at baseline are effective for prediction of outcome.

Adolescent↗

PubMed1994

Reinduction with the same cytostatic treatment in patients with metastatic breast cancer: an Eastern Cooperative Oncology Group study.

PURPOSE: To investigate the therapeutic value of reinduction with the same cytostatic treatment that had been used in induction treatment for women with metastatic breast cancer. MATERIALS AND METHODS: One hundred six women with metastatic breast cancer were given dibromodulcitol (mitolactol), doxorubicin, vincristine, tamoxifen, and fluoxymesterone (DAVTH) for 6 months of induction treatment, then randomized to receive one of two chemotherapy regimens if they had obtained an induction partial response (PR) or no change (NC), or to receive observation versus chemotherapy if they had obtained an induction complete response (CR). Patients were then retreated with DAVTH reinduction after relapse. RESULTS: Seventy-four patients were eligible or had minor reasons for ineligibility. Severe or life-threatening toxicity was documented in 46%, and lethal toxicity in 4%. Eighteen percent had a response on reinduction (zero of 16 induction nonresponders, 15% induction PR, 44% induction CR). The median time to treatment failure (TTF) from reinduction was 3 months, and the median survival duration from reinduction was 14 months. In a logistic model, factors associated with more reinduction responses were observation after induction CR (P = .002) and age greater than 55 years (P = .04). Time since induction was not significant. CONCLUSION: Reinduction of response after treatment failure remains a therapeutic problem. The need for better salvage treatment underlines the importance of developing new regimens.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2000

Competitive displacement among post-Paleozoic cyclostome and cheilostome bryozoans.

Encrusting bryozoans provide one of the few systems in the fossil record in which ecological competition can be observed directly at local scales. The macroevolutionary history of diversity of cyclostome and cheilostome bryozoans is consistent with a coupled-logistic model of clade displacement predicated on species within clades interacting competitively. The model matches observed diversity history if the model is perturbed by a mass extinction with a position and magnitude analogous to the Cretaceous/Tertiary boundary event, Although it is difficult to measure all parameters in the model from fossil data, critical factors are intrinsic rates of extinction, which can be measured. Cyclostomes maintained a rather low rate of extinction, and the model solutions predict that they would lose diversity only slowly as competitively superior species of cheilostomes diversified into their environment. Thus, the microecological record of preserved competitive interactions between cyclostome and cheilostome bryozoans and the macroevolutionary record of global diversity are consistent in regard to competition as a significant influence on diversity histories of post-Paleozoic bryozoans.

Animals↗

PubMed1998

At-risk drinking in an HMO primary care sample: prevalence and health policy implications.

OBJECTIVES: This study was designed to determine the prevalence of at-risk drinking using varying alcohol use criteria. METHODS: A period prevalence survey was conducted in 22 primary care practices (n = 19372 adults). RESULTS: The frequency of at-risk alcohol use varied from 7.5% (World Health Organization criteria) to 19.7% (National Institute on Alcohol Abuse and Alcoholism criteria). A stepwise logistic model using National Institute on Alcohol Abuse and Alcoholism criteria found male gender, current tobacco use, never married status, retirement, and unemployment to be significant predictors of at-risk alcohol use. CONCLUSIONS: Public health policy needs to move to a primary care paradigm focusing on identification and treatment of at-risk drinkers.

Adult↗