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PubMed2000

Assessment of quality of life in a single centre dialysis population using the KDQOL-SF questionnaire.

Health-related quality of life (HRQOL) is a valid marker of outcome for chronic dialysis therapy. A wide range of questionnaires are now available which assess different aspects of an individual's health. Appreciation of those factors that contribute to explaining HRQOL items remains poorly defined. The development of disease-specific questionnaires such as KDQOL-SF, should allow for such questions to be better answered. A cross-sectional analysis of our chronic dialysis population was made using the KDQOL-SF questionnaire. By multiple linear regression analysis demographic, clinical and dialysis-related factors were assessed for their contribution to the HRQOL in this population. The HRQOL of these patients was also compared against a general population sample. From a total of 190 chronic dialysis patients, 146 completed the KDQOL-SF questionnaire. The haemodialysis (HD) and peritoneal dialysis (PD) patients were similar with respect to most demographic, clinical and dialysis variables except for haemoglobin and albumin which were significantly (p < 0.05) greater in the peritoneal and haemodialysis populations respectively. Compared to the general population, the HRQOL of dialysis patients was impaired for all SF-36 subscales. Use of the disease-specific components of KDQOL-SF discriminated between dialysis modality for our dialysis population. Multiple linear regression analysis demonstrated that 27.5 to 42.7% of the variance in the SF-36 subscales could be explained. Satisfactory sleep, dialysis related symptoms, effect of kidney disease on lifestyle and burden of kidney disease were found to be the most important determinants of HRQOL for this population.

Aged↗

PubMed1994

The use of epidemiological concepts and techniques to discern factors associated with the nitrate concentration of well water on swine farms in the USA.

This epidemiological study investigates the relationship between various factors associated with swine farms and the nitrate concentration of well water in the USA. Through a random sampling procedure, 605 swine farms located in 18 states were selected for inclusion in this study. A total of 631 well water samples were collected from these farms and tested for a variety of elements and compounds. The concentrations of nitrate, nitrite, sulfate, chloride, sodium, potassium, ammonia, fluoride, bromide and lithium were determined by an ion chromatograph while an inductively coupled argon plasma emission spectrophotometer was used to determine the concentrations of calcium, magnesium, barium, zinc, iron and phosphate. Data concerning various farm factors were gathered via a personally administered questionnaire. The data were examined using both multiple linear regression and logistic regression. Results indicate that 53.6% (338/631) of the wells contained detectable levels of nitrate, 11.7% (74/631) had nitrate levels exceeding 45 ppm and 4.3% (27/631) exceeded 100 ppm. Logistic models demonstrated an association between nitrate concentrations > 45 ppm, increasing water potassium levels and wells < 100 ft deep. Nitrate levels > 100 ppm were related to increasing water concentrations of potassium, magnesium, barium and zinc, wells 6-10 years old, increasing distance from the study farm to the nearest cattle farm and a greater distance to the nearest waterway located off the study farm. A negative association was seen between nitrate concentrations > 100 ppm, the water level of sulfate, and the use of the same well to supply both the household and livestock. Multiple linear regression models revealed a positive association between increasing nitrate concentration and the water levels of chloride, calcium, zinc and the greater number of miles from the study farm to the nearest farm with cattle or sheep. A negative association was noted between the concentration of well water nitrate and the water levels of sulfate and ammonia, the use of water treatment, the number of miles to the nearest farm with poultry, the employment of water treatment and the use of the same well to supply water to both livestock and the household.

Agriculture↗

PubMed1993

Menadione nicotinamide bisulfite is a bioactive source of vitamin K and niacin activity for chicks.

Young chicks were fed a vitamin K-deficient soybean concentrate basal diet containing graded levels of menadione from menadione nicotinamide bisulfite (MNB) or menadione dimethyl-pyrimidinol bisulfite (MPB) to assess prothrombin time as a function of menadione intake. Prothrombin time decreased linearly as menadione dose increased from 0 to 400 micrograms/kg. Multiple linear regression slope-ratio calculations indicated that both sources of menadione were of equal potency. To assess niacin bioactivity of MNB, graded doses of nicotinamide (0 to 5 mg/kg) from MNB or nicotinamide were added to a niacin-deficient diet based upon corn, corn gluten meal and vitamin-free casein. Weight gain increased linearly as a function of nicotinamide dose, and multiple linear regression analysis of weight gain as a function of supplemental nicotinamide intake revealed no significant differences in slope between the two sources of nicotinamide. Using excess doses, MNB was compared with MPB in acute (single crop intubation) or chronic (fed in the diet for 14 d) toxicity trials. With a single menadione dose of 1600 mg/kg body wt, weight gain in the subsequent 14-d period was reduced by MNB but not by MPB. Mortality rates of 25 and 17% occurred for MPB and MNB, respectively, at this dose level. Doses lower than 1600 mg/kg body wt caused neither morbidity nor mortality. When provided in the diet for a 14-d feeding period, menadione doses of 3000 mg/kg diet from MNB reduced gain, feed intake, gain:feed ratio and blood hemoglobin concentration. Menadione doses of 6000 mg/kg diet were required to produce morbidity of this type when MPB was fed.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

PubMed2002

Acid reflux is a poor predictor for severity of erosive reflux esophagitis.

It is unknown which factors determine the severity of mucosal damage in gastroesophageal reflux disease (GERD). Our aim was to test whether the amount of esophageal acid exposure could predict the severity of esophageal injury in erosive reflux esophagitis. A total of 644 outpatients with symptomatic GERD underwent an esophagogastroduodenoscopy followed by esophageal manometry and 24-h pH monitoring. GERD was graded according to the endoscopic severity of mucosal damage as no erosions, single erosions, confluent erosions, esophageal ulcers, and strictures. A multiple linear regression was used to assess the joint influences of demographic characteristics, social habits, endoscopic anatomy, and various parameters of esophageal function tests on the severity of erosive reflux disease. No clear-cut association between the amount of acid reflux and the severity of erosive reflux esophagitis could be established. All individual parameters of esophageal pH monitoring, such as upright or supine acid contact time, frequency of all or only long reflux episodes, and an overall summary score of pH-metry, revealed no or only a weak correlation with the severity grade of erosive reflux esophagitis. Similarly, the pressure of the lower esophageal sphincter was only slightly more decreased in patients with extensive erosive esophagitis as compared to subjects without esophageal erosions. In the multiple linear regression, the presence of hiatus hernia was a stronger predictor of disease severity than any of the other parameters. In conclusion, factors other than exposure of the esophageal mucosa to acid must contribute to the development of erosive esophagitis.

Aged↗

PubMed2006

Interrelation of peri-operative morbidity and ASA class assignment in patients undergoing gynaecological surgery.

OBJECTIVE: The aim of this study was to estimate intra- and post-operative risk using the American Society of Anaesthesiologists (ASA) classification which is an important predictor of an intervention and of the entire operating programme. STUDY DESIGN: In this retrospective study, 4435 consecutive patients undergoing elective and emergency surgery at the Gynaecological Clinic of the University Hospital of Zurich were included. The ASA classification for pre-operative risk assessment was determined by an anaesthesiologist after a thorough physical examination. We observed several pre-, intra- and post-operative parameters, such as age, body-mass-index, duration of anaesthesia, duration of surgery, blood loss, duration of post-operative stay, complicated post-operative course, morbidity and mortality. The investigation of different risk factors was achieved by a multiple linear regression model for log-transformed duration of hospitalisation. RESULTS: Age and obesity were responsible for a higher ASA classification. ASA grade correlates with the duration of anaesthesia and the duration of the surgery itself. There was a significant difference in blood loss between ASA grades I (113+/-195 ml) and III (222+/-470 ml) and between classes II (176+/-432 ml) and III. The duration of post-operative hospitalisation could also be correlated with ASA class. ASA class I=1.7+/-3.0 days, ASA class II=3.6+/-4.3 days, ASA class III=6.8+/-8.2 days, and ASA class IV=6.2+/-3.9 days. The mean post-operative in-hospital stay was 2.5+/-4.0 days without complications, and 8.7+/-6.7 days with post-operative complications. Multiple linear regression model showed that not only the ASA classification contained an important information for the duration of hospitalisation. Parameters such as age, class of diagnosis, post-operative complications, etc. also have an influence on the duration of hospitalisation. CONCLUSION: This study shows that the ASA classification can be used as a good and early available predictor for the planning of an intervention in gynaecological surgery. The ASA classification helps the surgeon to assess the peri-operative risk profile of which important information can be derived for the planning of the operation programme.

Adult↗

PubMed2002

Chromatographic and ionization properties of polybrominated diphenyl ethers using GC/high-resolution MS with metastable atom bombardment and electron impact ionization.

The chromatographic and ionization properties of 35 polybrominated diphenyl ether (PBDE) congeners were investigated using GC/HRMS with metastable atom bombardment (MAB) and electron impact (EI) ionization. A multiple linear regression model based on bromine substitution patterns and MOPAC calculated physical properties was developed to predict relative GC retention times of individual PBDE congeners. Although five different sources of metastable rare gas atoms (He, N2, Ar, Xe, and Kr) were investigated with MAB ionization, only MAB-N2 provided adequate ionization efficiency and predictability. Because of reduced background noise to the MS detector, MAB-N2 had a lower limit of detection for tetra- and penta-BDEs than EI, despite having a lower sensitivity. Using MAB-N2, the molecular ion was always the base peak, with little fragmentation taking place. Conversely, using EI ionization, the [M - nBr]+ peak (where n = 1-4, depending on the number of Br substituents) was the dominant ion for all PBDE congeners. Multiple linear regression models representing the molecular ion response of PBDE congeners analyzed by GC/ HRMS with MAB-N2 and EI ionization were also developed using the number and type of Br substituents and ionization potentials. A significantly higher level of predictability was obtained for the MAB-N2 response model than for EI.

Electrons↗

PubMed1999

Potential risk factors associated with thrombocytopenia in a surgical intensive care unit.

We conducted a retrospective chart review of 193 patients admitted during a 3-month period to determine the frequency of and potential risk factors associated with thrombocytopenia, and the association of acquired thrombocytopenia with length of stay in a surgical-trauma intensive care unit (SICU) and mortality. All records were reviewed beginning 24 hours after admission. Patients were followed for the duration of SICU stay or until death. Data collected and analyzed as potential risk factors for thrombocytopenia were age, gender, admitting diagnosis, classification (trauma, surgical, medical), APACHE II score, medical history, all scheduled drugs with start and stop dates, select laboratory values, arterial or central line placement, and complications. Thrombocytopenia occurred in 25 (13%) patients. These patients were more likely (p<0.05) than those without thrombocytopenia to have the following potential risk factors: presence of a central or arterial line (76% vs 46%, p<0.025), nonsurgical diagnosis (60% vs 37%, p<0.05), diagnosis of sepsis (p<0.001), and administration of phenytoin (p<0.01), piperacillin (p<0.005), imipenem-cilastatin (p<0.001), and vancomycin (p<0.005). A longer SICU stay (mean 21 vs 4.5 days, p<0.05) and increased mortality (16% vs 4%, p<0.05) were significantly associated with thrombocytopenia. Cefazolin administration was significantly associated with nonthrombocytopenia (p<0.05). Factors not associated with thrombocytopenia were age, gender, and administration of histamine2-receptor antagonists, heparin, enoxaparin, penicillins, ceftazidime, ceftriaxone, chloramphenicol, and amphotericin B. A central or arterial line was the only factor associated with the development of thrombocytopenia in a multiple linear regression analysis (p=0.0003, multiple r=0.2580). Thrombocytopenia is not a common occurrence in the SICU, but is associated with a longer SICU stay and increased mortality.

Adolescent↗

PubMed1991

Predictors and prevalence of obstructive sleep apnoea and snoring in 1001 middle aged men.

One thousand and one men, aged 35-65 years, were identified from the age-sex register of one group general practice. Over four years 900 men were visited at home and asked questions about symptoms potentially related to sleep apnoea and snoring. Height, weight, neck circumference, resting arterial oxygen saturation (SaO2), and spirometric values were also determined. All night oximetry was then performed at home and the tracing analysed for the number of dips in SaO2 of more than 4%. Subjects with more than five dips of 4% SaO2 or more per hour were invited for sleep laboratory polysomnography. Seventeen per cent of the men admitted to snoring "often." Multiple linear regression techniques identified and ranked neck circumference (r2 = 7.2%), cigarette consumption (r2 = 3.4%), and nasal stuffiness (r2 = 2%) as the only significant independent predictors of snoring. Together these account for at least a sixfold variation in the likelihood of being an "often" snorer. Forty six subjects (5%) had greater than 4% SaO2 dip rates of over five an hour and 31 of these had full sleep studies. Three subjects had clinically obvious and severe symptomatic obstructive sleep apnoea, giving a prevalence of three per 1001 men (0.3%; 95% confidence interval 0.07-0.9%). Eighteen men had obstructive sleep apnoea only when supine and in 10 the cause of the SaO2 dipping on the original home tracing was not elucidated. The greater than 4% SaO2 dip rates correlated with the history of snoring. Multiple linear regression techniques identified and ranked neck circumference (r2 = 7.9%), alcohol consumption (r2 = 3.7%), age (r2 = 1%) and obesity (r2 = 1%) as the only significant independent predictors of the rate of overnight hypoxic dipping. This study shows that snoring in this randomly selected population correlates best with neck size, smoking, and nasal stuffiness. Obstructive sleep apnoea, defined by nocturnal hypoxaemia, correlates best with neck size and alcohol, and less so with age and general obesity.

Adult↗

PubMed2005

[Epidemic survey of the middle and aged women related obstructive sleep apnea hypopnea syndrome in Beijing].

OBJECTIVE: To find out the prevalence and risk factors related obstructive sleep apnea hypopnea syndrome (OSAHS) in Chinese women aged 40 years and older. METHODS Participants living in communities must be of age > or = 40 years and were given questionnaires, which developed a scale of 11 questions. Subjects were divided into three groups by scale scores. Those with higher scores were oversampled (2.4%, 14.8%, 42.1% respectively) and subjects of this community-based sample were recorded in the sleep laboratory to ascertain patients (apnea hypopnea index, AHI > or = 5/h and daytime sleepiness). Contrasting patients with the others as a control group, explored differences in symptoms. Stepwise multiple linear regression was used to determine the principal covariates affecting AHI. RESULTS: 34.3% of 1336 eligible women admitted various degree of snoring and 91.0% of those completed questionnaires. Crombach's alpha coefficient of scale reached 0. 7025. Factor analysis reduced 11 questions of scale to four common factors as we have designed: snoring, apneas, other symptoms, risk factors. Fifty-nine subjects experienced polysomnography evaluation. The ratios of patients to controls were 2: 25, 4: 18, 10: 16 from lower scores group to higher. We estimated the prevalence of AHI 5,10,15/h and OSAHS in this population were 41.1%, 24.0%, 17.0% and 11.1%, respectively. As far as the frequency of sleep choking, xerostomia or pharyngoxerosis in the morning, these were significant differences between the OSAHS and non-OSAHS groups. Stepwise multiple linear regression analysis identified serum level follicle-stimulating hormone and BMI as predictors of AHI. CONCLUSIONS: This scale had good validity and reliability. Snoring and OSAHS are very common in Chinese women 40 years of age and older. Women with OSAHS did report sleep choking, xerostomia or pharyngoxerosis in the morning. BMI and sex steroids may all play a role in OSAHS.

Adult↗

PubMed2003

Ventilatory functions in Croatian population in comparison with European reference values.

AIM: To compare ventilatory capacity of Croatian population with the ventilatory function values predicted by conventional equations based on measurements among European populations. METHODS: Ventilatory capacity and respiratory symptoms were determined in a group of 2,482 healthy non-smokers (1,162 men and 1,320 women). The measurements were performed with a pneumotach spirometer. Maximum expiratory flow volume curves (MEFV) were registered, and forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and flow rates at 50% (MEF50) and the last 25% of the vital capacity (MEF25) were recorded. Anthropometric data were also noted. Reference values were calculated using multiple linear regressions. RESULTS: Comparisons of our values with the prediction summary equations issued by the European Community for Steel and Coal (ECSC) and the European Respiratory Society (ERS) showed that healthy Croatians had consistently lower values of FVC (92.1-/+14.0% of the predicted volume for men and 86.2-/+11.7% for women) and FEV1 (93.7-/+14.8% of the predicted values for men and 95.3-/+13.1% for women), but higher values of MEF50 (107.8-/+30.1% of the predicted values for men and 103.4-/+22.8% for women) and MEF25 (117.3-/+41.0% of the predicted values for men and 117.9-/+34.0% for women) than the ECSC/ERS recommendations. The comparison was also made with the most commonly used North American reference standards based on populations of European origin, with similar findings. On the basis of the results of multiple linear regressions, we constructed prediction equations for ventilatory function in Croatian population. CONCLUSION: The ECSC/ERS recommendations are not satisfactory for the Croatian population.

Adult↗

PubMed2002

Mechanisms of myopia in Cohen syndrome mapped to chromosome 8q22.

PURPOSE: To analyze the mechanisms of myopia in Cohen syndrome (Mendelian Inheritance in Man [MIM] no. 216550). METHODS: A cross-sectional study of 22 Finnish patients (age range, 2-57 years) with Cohen syndrome, which maps to chromosome 8q22, was undertaken to record cycloplegic refraction, keratometry (corneal power and radius of curvature), biometry (anterior chamber depth [ACD], lens thickness [LT], axial [AL] and vitreal length [VL]), and Hoffer Q-modeled lens power. These components of refraction were correlated to age and spherical equivalent (SE) at the corneal plane. Contribution to total myopia of refractive (corneal and lenticular) and axial components was modeled by multiple linear regression and by estimating the effect of deviation from population mean values. RESULTS: The mean SE in patients with Cohen syndrome older than 10 years was -9.35 D; the mean cylinder power, +1.70 D; and the mean anisometropia, 0.53 D. Relative to the emmetropic eye of a young adult, the AL and VL (mean, 23.9 and 16.6 mm, respectively) and lens power (mean, 30.30 D) were higher in 74% and 93% of patients, respectively, and the ACD (mean, 2.5 mm) was smaller and the LT (mean, 4.9 mm) and corneal power (mean, 45.63 D) higher than average in all patients. Corneal power (r = 0.513, P = 0.021) increased with age, but AL and VL (P = 0.46 and 0.54, respectively) and lens power (P = 0.89) did not correlate with age. The lens power decreased with AL (r = -0.564, P = 0.029) and tended to increase with corneal power (r = 0.475, P = 0.074). Multiple linear regression identified AL and corneal power as independent predictors of SE. Based on deviation from population means, the lens power explained 55%, corneal power 23%, and AL 22% of total myopia. ACD decreased and LT increased markedly with age, rendering angle-closure glaucoma a possibility. CONCLUSIONS: Myopia in Cohen syndrome is mainly refractive in type and is due to high corneal and lenticular power, which is otherwise rare in young patients. It may be superimposed on axial myopia, probably related to polygenic factors that determine myopia in the general population. The refractive myopia in Cohen syndrome may result from dysgenesis and atrophy of the cornea, ciliary body, and iris, which in turn cause iridial and zonular laxity and spherophakia.

Abnormalities, Multiple↗

PubMed1996

Interleukin-2 receptor levels in sera of patients with rheumatoid arthritis treated with sulfasalazine, parenteral gold, or placebo.

OBJECTIVE: To evaluate the associations of soluble serum interleukin-2 receptor (sIL-2R) levels in patients with rheumatoid arthritis (RA) with clinical and laboratory measures of disease activity and the predicted response to therapy. METHODS: sIL-2R levels were determined by ELISA in 137 patients with RA, not previously treated with 2nd line therapy. Patients were enrolled in a prospective, randomized, placebo controlled trial of sulfasalazine (SSZ) versus gold sodium thiomalate (GSTM), sponsored by the Cooperative Systematic Studies of Rheumatic Diseases. Using correlation analysis and regression modeling, the clinical utility of sIL-2R as a measure of disease activity and predictor of outcome was assessed. RESULTS: 91 women and 46 men with a mean age of 51 +/- 13 years and mean duration of disease of 64 +/- 78 months participated in this study. The mean sIL-2R level in all patients with RA was markedly elevated (980 +/- 589 U/ml) compared with that in healthy control subjects (446 +/- 196 U/ml; p = < 0.0001). There was no correlation between the sIL-2R levels and the joint pain/tenderness count, either at study entry or completion. There were significant positive correlations between the baseline sIL-2R and baseline erythrocyte sedimentation rate (ESR) and between the change in sIL-2R and the change in ESR. Both a multiple linear regression model and a multiple logistic regression model showed that baseline sIL-2R levels were not predictive of clinical outcome. CONCLUSION: sIL-2R levels are significantly elevated in patients with active RA and correlate positively with ESR. However, these results indicate that in patients with early RA, sIL-2R levels are neither associated with standard disease activity criteria nor predictive of the response to therapy with SSZ or GSTM, even after controlling for the simultaneous effects of other important clinical variables.

Adult↗

PubMed1995

Use of anthropometric measurements in assessing risk for coronary heart disease: a useful tool in worksite health screening?

The study examined the association between the anthropometric measurements body mass index (BMI), waist/hip ratio (WHR), and waist/thigh ratio (WTR) and cardiovascular risk factors, and assessed whether a combination of BMI and WHR could be used in routine screening of risk for cardiovascular arteriosclerotic disease at worksites. The data were obtained from a cross-sectional survey designed to assess the nutritional situation, with special reference to cardiovascular risk factors. The study population comprised 372 healthy men working on platforms in the North Sea. Serum cholesterol, triglyceride, fibrinogen, and blood pressure were positively related to the anthropometric variables, while high-density lipoprotein (HDL) was inversely related with them. The relations remained after adjusting for possible confounders, such as age, smoking, physical activity, and an indicator of dietary fat intake. In stepwise multiple linear regression models, BMI, WHR, and WTR were positively related to serum cholesterol, triglycerides, fibrinogen, diastolic blood pressure, and systolic blood pressure, and inversely related to HDL. When controlling for the anthropometric variables WHR and WTR, BMI was not independently related to fibrinogen and risk score. WHR and WTR were not independently related to systolic and diastolic blood pressure, and WTR was in addition not related to triglycerides when controlling for BMI. Overall, the anthropometric variables BMI and WHR were considered the best predictors for CAD risk when taking several risk factors into consideration. A joint variable between BMI and WHR, called "body score", constituted the four categories lean, lean android, overweight gynoid, and overweight ovoid. This body score was positively associated with levels of serum lipids, fibrinogen, and blood pressure, and inversely associated with HDL. In stepwise multiple linear regression models, controlling for possible confounding variables, body score was positively related to CAD risk. Dividing the risk score into tertiles, about 51% of the lean were in the first, while 46% of the overweight ovoid were in the third tertile. Those classified as lean android or overweight gynoid had about the same distribution, namely between 31% and 39% in each tertile if the two categories were combined. These data support the hypothesis that BMI, WHR, and WTR are independent predictors for risk factors for CAD among oil workers, and that combinations of BMI and WHR are strong enough predictors to be useful in routine screening for CAD risk at worksites. Based on these findings, supported by data from the literature, a matrix aimed at screening for follow-up at worksites is proposed.

Adult↗

PubMed2005

Increased radiographic damage scores at the onset of seropositive rheumatoid arthritis in older patients are associated with osteoarthritis of the hands, but not with more rapid progression of damage.

OBJECTIVE: To investigate the impact of patient age at symptom onset on radiographic joint damage at study entry, and on subsequent progression of damage in a cohort of patients with early seropositive rheumatoid arthritis (RA). METHODS: We studied 186 patients with RA of <15 months' duration. All patients had active disease and had not received disease-modifying antirheumatic drugs. At study entry and during followup, total Sharp scores (TSS), RA-associated joint space narrowing (RA-JSN), and erosions were determined on hand and foot radiographs. Baseline radiographs were also scored for osteoarthritis (OA)-related JSN (OA-JSN) and osteophytes. Older patients (>55 years) and younger patients (</=55 years) were compared by t-test, Mann-Whitney U test, chi-square, or Fisher's exact test. Multiple linear regression models were also constructed. RESULTS: The older group (n = 74) had a higher baseline total Sharp score (median 6.21) compared with the younger group (n = 112) (median 2.33) (P = 0.0002). This was mainly due to a higher baseline JSN score in the older group (median 3.96 versus 1.08) and not to differences in erosion score (median 0.91 versus 0.70). Disease activity and duration of RA symptoms were similar in the 2 groups, as were progression rates of the TSS, JSN score, and erosion score. At baseline, 26% of patients had osteophytes, with a prevalence of 13% in the younger age group and 50% in the older group. The presence of OA-JSN was highly correlated with the presence of osteophytes (r = 0.72). Also, increased age and RA-JSN were associated with increased severity of osteophytes and OA-JSN at baseline. Multiple linear regression analysis showed that both age and hand osteophytes contributed to the increase in baseline RA-JSN score and TSS, but not to erosion score. CONCLUSION: In a cohort of patients with early RA, an increase in the baseline RA-JSN score and TSS can be accounted for in part by the presence of hand OA.

Adult↗

PubMed2002

Combined effect of hypothermia and crystalloid hemodilution on the solubility of volatile anesthetics in human blood.

OBJECTIVE: To determine the combined effect of hypothermia and crystalloid hemodilution on blood solubility of volatile anesthetics. METHODS: Two hundred and thirty ml blood samples obtained from each of twelve healthy male volunteers were adjusted to a hematocrit of 40% and then diluted with normal saline to hematocrits of 36%, 32%, 28%, 24%, and 20%. Blood/gas partition coefficients of desflurane, sevoflurane, isoflurane, enflurane and halothane were measured at 37 degrees C,33 degrees C, 29 degrees C, 25 degrees C, 21 degrees C and 17 degrees C using a two-stage headspace double equilibration method. RESULTS: As the temperature decreased, the logarithm of the blood/gas partition coefficient increased linearly (P < 0.05). As the hematocrit decreased, the logarithm of the blood/gas partition coefficient decreased linearly (P < 0.05). The combined effect of hypothermia and crystalloid hemodilution on blood solubility of anesthetics was expressed by multiple linear regression equations as follows: Desflurane: log(e)lambda(B/G)=-0.0302 x T+0.0094 x HCT+0.119 R(2)=0.973. Sevoflurane: log(e)lambda(B/G)=-0.0295 x T+0.0092 x HCT+0.306 R(2)=0.961. Isoflurane: log(e)lambda(B/G)=-0.0382 x T+0.0154 x HCT+1.120 R(2)=0.997. Enflurane: log(e)lambda(B/G)=-0.0408 x T+0.0198 x HCT+1.408 R(2)=0.982. Halothane: log(e)lambda(B/G)=-0.0417 x T+0.0218 x HCT+1.649 R(2)=0.994. Where lambda(B/G) is the blood/gas partition coefficient, T is temperature (degrees C) and HCT is hematocrit (%). CONCLUSIONS: Hypothermia increases, while crystalloid hemodilution decreases the blood solubility of volatile anesthetics. The combined effect of hypothermia and hemodilution on blood solubility at any cross point of temperature from 37 degrees C to 17 degrees C and hematocrit from 40% to 20% could be predicted by the multiple linear regression equations developed in this study.

Adult↗

PubMed2005

Circulating soluble leptin receptor, leptin, and insulin resistance before and after weight loss in obese children.

OBJECTIVE: To study the relationships between leptin, soluble leptin receptor (sOB-R), and insulin resistance in obese children before and after weight reduction. METHODS: We determined fasting serum leptin, sOB-R, and insulin resistance index (Homeostasis model assessment (HOMA)) in 36 obese children at baseline and 1 y later and compared them to 72 lean children matched for age, gender, and pubertal stage. The changes of leptin (Deltaleptin) and sOB-R (DeltasOB-R) over the 1 y period were correlated to the changes of HOMA (DeltaHOMA), the changes of weight status, and the changes of percentage body fat (Delta%BF) based on skinfold measurements. Multiple linear regression analyses were conducted for the dependent variables Deltaleptin and DeltasOB-R, including DeltaBMI and DeltaHOMA as independent variables adjusted for age, gender, and pubertal stage. Changes of leptin and sOB-R levels were analyzed in 11 obese children after they had lost weight substantially (decrease SDS-BMI>0.5) and compared to 11 obese children without substantial weight loss matched for age, gender, and pubertal stage. RESULTS: Obese children showed significantly (P<0.001) higher leptin and lower sOB-R levels. Deltaleptin correlated significantly to DeltaSDS-BMI (r=0.28, P<0.05), Delta%BF (r=0.44, P<0.05), and DeltaHOMA (r=0.42, P<0.01), while DeltasOB-R correlated significantly to DeltaSDS-BMI (r=-0.42, P<0.01) and Delta%BF (r=-0.47, P<0.01), but not to DeltaHOMA. In contrast to DeltasOB-R, Deltaleptin correlated significantly to DeltaHOMA (P=0.02) in multiple linear regression analysis. Substantial weight loss led to a significant increase in sOB-R (P=0.02) and to a decrease in HOMA (P=0.02). In children without substantial weight loss, there were no changes in sOB-R, while HOMA (P=0.04) and leptin (P=0.02) increased significantly. CONCLUSIONS: The decrease of sOB-R and the increase of leptin levels in obese children normalized after weight loss. Therefore, these changes are consequences rather than the cause of overweight. In contrast to sOB-R, leptin levels are associated with insulin resistance.

Adolescent↗

PubMed2001

The health burden of breast hypertrophy.

Women seeking consultation for the surgical relief of symptoms associated with breast hypertrophy have been the focus of many studies. In contrast, little is known about those women with breast hypertrophy who do not seek symptomatic relief. The purpose of this study was to describe the health burden of breast hypertrophy by using a set of validated questionnaires and to compare women with breast hypertrophy who seek surgical treatment with those who do not. In addition, this latter group was compared with a group of control women without breast hypertrophy. Women seeking consultation for surgery were recruited from 14 plastic-surgery practices. Control subjects were recruited by advertisements in primary-care offices and newspapers. Women were asked to complete a self-report questionnaire that included the European Quality of Life (EuroQol) questionnaire, McGill Pain Questionnaire, Multidimensional Body Self Relations Questionnaire (MBSRQ), the Short Form-36 (SF-36) questionnaire, and questions regarding breast-related symptoms, comorbidities, and bra size. Descriptive statistics were compiled for three groups of women: (1) hypertrophy patients seeking surgical care, (2) hypertrophy control subjects (those whose reported bra-cup size was a D or larger), and (3) normal control subjects (those whose reported bra-cup size was an A, B, or C). The multiple linear regression method was used to compare the health burdens across groups while adjusting for other variables. Two hundred ninety-one women seeking surgical care and 195 control subjects were enrolled in the study. The 184 control subjects with bra-cup information available were further separated into 88 hypertrophy control subjects and 96 normal control subjects. In the control group, bra-cup size was correlated with health-burden measures, whereas in the surgical candidates, it was not. When scores were compared across the three groups, significant differences were found in all health-burden measures. The surgical candidates scored more poorly on the EuroQol utility, McGill pain rating index, MBSRQ appearance evaluation, physical component scale of the SF-36, and on breast symptoms than did the two control groups. In addition, the hypertrophy control subjects scored more poorly than the normal control subjects. With multiple linear regression analysis incorporating important potential confounders, the poorer scores in the surgical candidates remained statistically significant. It was concluded that breast hypertrophy in those seeking surgical care and those not seeking surgery has a significant impact on women's quality of life as measured by validated and widely used self-report instruments including the EuroQol, MBSRQ, McGill Pain Questionnaire, and the SF-36. Likewise, a new assessment instrument for breast-related symptoms also demonstrated greater symptomatology in women with breast hypertrophy.

Adult↗

PubMed1999

Factors influencing knowledge of and adherence to self-care among patients with heart failure.

BACKGROUND: Patient education has been shown to be a key component in comprehensive heart failure management. Few data, however, are available regarding patients' knowledge of and adherence to self-care recommendations for the disease. OBJECTIVES: To assess the knowledge level of and adherence to self-care among patients with heart failure and to determine associated factors. METHODS: We conducted a needs-assessment survey among new patients visiting a heart failure clinic from April 1997 through June 1998. Multiple linear regression analysis was used to assess the factors predictive of patients' knowledge level and adherence behaviors. RESULTS: Of the 113 patients surveyed, 77% were referred by cardiologists and 60% had New York Heart Association class III or IV status. Two thirds of the patients reported receiving information or advice about self-care from health care providers. When asked how much they knew about congestive heart failure, however, 37% said "a little or nothing," 49% said "some," and only 14% said "a lot." Approximately 40% of the patients did not recognize the importance of weighing themselves daily and 27% weighed themselves twice a month or less often. Although 80% of the patients knew they should limit their salt intake, only one third always avoided salty foods. Additionally, 25% of the patients did not appreciate the risk of alcohol use and 36% believed they should drink a lot of fluids. The multiple linear regression analysis indicated that a higher knowledge score was associated with being married, prior hospitalization, and having received both advice and information about self-care from physicians or nurses. A poor adherence behavior score was associated with being unmarried, lower perceived self-efficacy, a lack of knowledge about self-care, and no prior hospitalization. CONCLUSIONS: We observed a gap between patients receiving and absorbing or retaining information on self-care for congestive heart failure supplied by health care providers. Self-care education needs to be directed to outpatients in addition to inpatients.

Adult↗