Regression Coefficient Beta Research Articles

Horizontal and vertical optic disc rotation. The Beijing Eye Study.

PurposeTo measure the optic disc rotation around the vertical and horizontal disc axis and to evaluate associations with general and ocular parameters.DesignPopulation-based studyMethodsIn the Beijing Eye Study, 3468 participants (mean age:64.6±9.8 years; range:50–93 years) underwent an ophthalmological examination which included spectral-domain optical coherence tomography (OCT) with enhanced depth imaging. Using the OCT images, we determined the amount of the rotation of the optic disc (defined as Bruch´s membrane opening (BMO)) around the vertical axis and horizontal axis.ResultsOptic disc rotation measurements were available for 3037 (87.6%) individuals. In multivariate analysis, larger optic disc rotation around the vertical axis (range:-4.90° to 41.0°) was associated (regression coefficient r:0.27) with high axial myopia (axial length ≥26.5 mm) (P<0.001;standardized regression coefficient beta beta:0.09), longer disc-fovea distance (P = 0.001;beta:0.09) and wider parapapillary beta/gamma zone (P<0.001;beta0.12). Larger optic disc rotation around the horizontal axis (range:-7.10° to 26.4°) was associated (r:0.32) with high axial myopia (P = 0.001;beta:0.08), larger optic disc-fovea angle (P<0.001;beta:0.13), thinner superior nasal retinal nerve fiber layer (RNFL) thickness (P<0.001;beta:-0.19) and thicker inferior nasal RNFL thickness (P<0.001;beta:0.17).ConclusionsVertical optic disc rotation was associated with highly myopic axial elongation, increased disc-fovea distance and development or enlargement of parapapillary, Bruch´s membrane free, gamma zone, while macular Bruch´s membrane length is not affected. Horizontal optic disc rotation was associated with inferior dislocation of the fovea, in addition to a thinner superior nasal RNFL and thicker inferior nasal RNFL. The latter association may be taken into account in the interpretation of RNFL thickness profiles.

Abstract MP090: Sleep Duration Predict Incident Obesity in Childhood and Adolescence: Meta-analysis of Prospective Studies

Objectives: To assess the longitudinal evidence of a relationship between duration of sleep and both incidence of overweight and/or obesity and changes in body mass index in infants, children and adolescents. Methods: We performed a systematic search of publications using MEDLINE (1966-2016), EMBASE (from 1980), Web of Science (from 1945), the Cochrane Library and manual searches without language restrictions. Studies were included if they were prospective, had a follow up &gt;1 year, had measured duration of sleep at baseline and assessed either incident cases of overweight and/or obesity or changes in body mass index prospectively. Relative risks (RR), regression coefficients (beta) and 95% C.I. were extracted and pooled using a random effect model. Sensitivity analyses and meta-regressions were performed, heterogeneity and publication bias were also assessed. Results: Overall, 41 studies provided 56 independent cohort samples, including 98,130 boys and girls aged 0-18 years (follow-up 1 to 27 years). Sleep duration was assessed by questionnaire, either to parents or to children, actigraphy or polysomnography. Body mass index (BMI) was measured in all participants. In the pooled analyses, short duration of sleep was associated with a greater risk of becoming overweight or obese (RR: 1.57; 95% CI 1.34, 1.85; p&lt;10 -5 ; n=59,471). There was significant heterogeneity (I 2 =92%, p&lt;0.001), accounted for by three studies (I 2 =3% after their removal) and evidence of publication bias (p=0.007). The effect size increased with age (infants 1.40 [1.19, 1.65]; early childhood 1.53 [1.33, 1.76]; middle childhood 2.23 [2.18, 2.27]; adolescence 1.30 [1.11, 1.53]; p for heterogeneity &lt;10 -5 ). The effect was not associated with average length of follow-up (p=0.923) or quality (p=0.475). BMI decreased for every hour of increased sleep (pooled beta: -0.01; -0.03, 0.00 kg/m 2 per h, p=0.032; n=16,225). Conclusion: Short duration of sleep is a significant predictor of the development of overweight, obesity and weight gain from birth to adolescence.

Abstract P5-03-04: To excise or not?: Scoring system for predicting malignancy in patients diagnosed with intraductal papilloma at ultrasound-guided core needle biopsy

Abstract Background: The management of benign intraductal papillomas on core biopsy is controversial. The aim of this study was to determine factors that predict under-evaluation of atypical lesion or malignancy in patients diagnosed with benign papilloma at ultrasound-guided core needle biopsy (CNB), and to develop a prediction algorithm for scoring the possibility of a diagnosis upgrade to atypical lesion or malignancy based on clinical, radiological and pathological factors. Methods: The study enrolled patients diagnosed with benign papilloma at ultrasound-guided CNB who subsequently underwent surgical excision of the lesion. Multivariate analysis was used to identify relevant clinical, radiological and pathological factors that may predict malignancy. Results: A total of 520 CNBs led to a diagnosis of benign papilloma (including benign and atypical papillary lesion), of which 452 CNBs were benign papilloma without atypia. Of the 250 lesions in 234 women were underwent subsequent surgical excision, 44 (17.6%) were diagnosed with atypia or malignancy. Multivariate analysis revealed that bloody nipple discharge, size on imaging ≥15 mm, BIRADS≥4b, peripheral location, and a palpable lesion were independent predictors of atypical lesion or malignancy. A scoring system was developed based on logistic regression models and beta coefficients for each variable. The area under the ROC curve was 0.830 (95% CI: 0.665-0.996), and the negative predictive value was 100% for a score ≤4. Conclusions: A scoring system to predict malignancy in patients diagnosed with benign papilloma at CNB was developed based on five factors: bloody nipple discharge, size on imaging ≥15 mm, BIRADS≥4b, peripheral location, and a palpable lesion. This system was able to identify a subset of patients with lesions likely to be benign, indicating that imaging follow-up rather than surgical excision may be appropriate. Citation Format: Ahn Sk, Moon H-G, Han W, Noh D-Y, Ko E. To excise or not?: Scoring system for predicting malignancy in patients diagnosed with intraductal papilloma at ultrasound-guided core needle biopsy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-03-04.

A new scoring system (DAIGA) for predicting bleeding complications in atrial fibrillation patients after drug-eluting stent implantation with triple antithrombotic therapy

BackgroundNo scoring system for evaluating the bleeding risk of atrial fibrillation (AF) patients after drug-eluting stent (DES) implantation with triple antithrombotic therapy (TAT) is available. We aimed to develop a new scoring system for predicting bleeding complications in AF patients after DES implantation with TAT. Methods and resultsBetween April 2007 and April 2014, 227 AF patients undergoing DES implantation with TAT were enrolled. Bleeding incidence defined as Bleeding Academic Research Consortium criteria≥2 was investigated and predictors of bleeding complications were evaluated using multivariate analysis. Bleeding complications occurred in 58 patients (25.6%) during follow-up. Multivariate analysis revealed dual antiplatelet therapy (DAPT) continuation (OR 3.33, P=0.01), age>75 (OR 2.14, P=0.037), international normalized ratio>2.2 (OR 5.82, P<0.001), gastrointestinal ulcer history (OR 3.06, P=0.037), and anemia (OR 2.15, P=0.042) as predictors of major bleeding complications. A score was created using the weighted points proportional to the beta regression coefficient of each variable. The DAIGA score showed better predictive ability for bleeding complications than the HAS-BLED score (AUC: 0.79 vs. 0.62, P=0.0003). Bleeding incidence was well stratified: 17.8% in low-risk (scores 0–1), 55.5% in moderate-risk (2-3), and 83.0% in high-risk (4-7) patients (P<0.001). ConclusionsThis scoring system is useful for predicting bleeding complications and risk stratification of AF patients after DES implantation with TAT.

Determinants of peripapillary retinal nerve fiber layer thickness regarding ocular and systemic parameters - the MIPH Eye&Health Study.

Optical coherence tomography (OCT) allows quantitative image analysis of retinal tissue in vivo. Peripapillary retinal nerve fiber layer (pRNFL) thickness is widely used for evaluation of retinal nerve fiber rarefaction in several optic neuropathies. This study evaluates associations of pRNFL thickness in healthy adult subjects in order to evaluate influencing factors. A cross-sectional study was performed in a working-age population. Only eyes without detectable ocular pathologies were included in the analysis. Among analyzed systemic cardiovascular parameters were age, gender, body-mass index, mean arterial blood pressure, HbA1c, high- and low-density-lipoproteins, and triglycerides. A comprehensive ophthalmological examination including refraction, tonometry, keratometry, and central corneal thickness measurmentwas performed. In addition, pRNFL thickness was imaged by spectral-domain OCT. Univariable and multivariable associations of pRNFL thickness in all four quadrants and on average with systemic and ocular parameters were calculated using a generalized estimating equation model. Three hundred and six subjects were included. pRNFL thickness measurements showed a significant association with spherical equivalent: pRNFL thickness decreased with increasing myopia in all quadrants (multivariable regression coefficients Beta: superior: 1.16, 95% CI [0.62;1.71], p < 0.001; temporal: 0.87, [0.33;1.41], p = 0.001; inferior: 1.80, [1.18;2.42], p < 0.001; nasal: 2.60, [2.01;3.20],p < 0.001) and on average (1.51, [1.20;1.82], p < 0.001). A thicker central cornea thickness was related to lower pRNFL in the superior (-0.05, [-0.10; -0.01], p = 0.01), the inferior quadrant (-0.05, [-0.10;0.00], p = 0.03) and on average (-0.04, [-0.07; -0.01], p = 0.02). All other parameters were not associated. Our findings highlight the importance of refraction when evaluating pRNFL thickness and its independence from other systemic parameters.

Plasma CTGF is independently related to an increased risk of cardiovascular events and mortality in patients with atherosclerotic disease: the SMART study

Aims: Connective tissue growth factor (CTGF) plays a key role in tissue fibrogenesis and growing evidence indicates a pathogenic role in cardiovascular disease. Aim of this study is to investigate the association of connective tissue growth factor (CTGF/CCN2) with cardiovascular risk and mortality in patients with manifest vascular disease. Methods and results: Plasma CTGF was measured by ELISA in a prospective cohort study of 1227 patients with manifest vascular disease (mean age 59.0 ± 9.9 years). Linear regression analysis was performed to quantify the association between CTGF and cardiovascular risk factors. Results are expressed as beta (β) regression coefficients with 95% confidence intervals (CI). The relation between CTGF and the occurrence of new cardiovascular events and mortality was assessed with Cox proportional hazard analysis. Adjustments were made for potential confounding factors. Plasma CTGF was positively related to total cholesterol (β 0.040;95%CI 0.013–0.067) and LDL cholesterol (β 0.031;95%CI 0.000–0.062) and inversely to glomerular filtration rate (β −0.004;95%CI −0.005 to −0.002). CTGF was significantly lower in patients with cerebrovascular disease. During a median follow-up of 6.5 years (IQR 5.3–7.4) 131 subjects died, 92 experienced an ischemic cardiac complication and 45 an ischemic stroke. CTGF was associated with an increased risk of new vascular events (HR 1.21;95%CI 1.04–1.42), ischemic cardiac events (HR 1.41;95%CI 1.18–1.67) and all-cause mortality (HR 1.18;95%CI 1.00–1.38) for every 1 nmol/L increase in CTGF. No relation was observed between CTGF and the occurrence of ischemic stroke. Conclusions: In patients with manifest vascular disease, elevated plasma CTGF confers an increased risk of new cardiovascular events and all-cause mortality.

Determinants of serum cadmium levels in a Northern Italy community: A cross-sectional study

IntroductionCadmium (Cd) is a heavy metal and a serious environmental hazard to humans. Some uncertainties still exist about major sources of Cd exposure in non-occupationally exposed subjects in addition to cigarette smoking, such as diet and outdoor air pollution. We sought to determine the influence of these sources on a biomarker of exposure, serum Cd concentration. MethodsWe recruited 51 randomly selected residents from an Italian urban community, from whom we obtained detailed information about dietary habits and smoking habits, and a blood sample for serum Cd determination. We also assessed outdoor air Cd exposure, by modeling outdoor air levels of particulate matter ≤10µm (PM10) from motorized traffic at geocoded subjects’ residence. ResultsIn crude analysis, regression beta coefficients for dietary Cd, smoking and PM10 on serum Cd levels were 0.03 (95% CI -0.83 to 0.88), 6.96 (95% CI -0.02 to 13.95) and 0.62 (95% CI -0.19 to 1.43), respectively. In the adjusted analysis, regression beta coefficients were -0.34 (95% CI -1-40 to 0.71), 5.81 (95% CI -1.43 to 13.04) and 0.47 (95% CI -0.35 to 1.29), respectively. ConclusionCigarette smoking was the most important factor influencing serum Cd in our non-occupationally exposed population, as expected, while dietary Cd was not associated with this biomarker. Outdoor air pollution, as assessed through exposure to particulate matter generated by motorized traffic, was an additional source of Cd exposure.

Feasibility of the "Bring Your Own Device" Model in Clinical Research: Results from a Randomized Controlled Pilot Study of a Mobile Patient Engagement Tool.

BackgroundRising rates of smartphone ownership highlight opportunities for improved mobile application usage in clinical trials. While current methods call for device provisioning, the "bring your own device” (BYOD) model permits participants to use personal phones allowing for improved patient engagement and lowered operational costs. However, more evidence is needed to demonstrate the BYOD model’s feasibility in research settings.ObjectiveTo assess if CentrosHealth, a mobile application designed to support trial compliance, produces different outcomes in medication adherence and application engagement when distributed through study-provisioned devices compared to the BYOD model.Methods87 participants were randomly selected to use the mobile application or no intervention for a 28-day pilot study at a 2:1 randomization ratio (2 intervention: 1 control) and asked to consume a twice-daily probiotic supplement. The application users were further randomized into two groups: receiving the application on a personal "BYOD” or study-provided smartphone. In-depth interviews were performed in a randomly-selected subset of the intervention group (five BYOD and five study-provided smartphone users).ResultsThe BYOD subgroup showed significantly greater engagement than study-provided phone users, as shown by higher application use frequency and duration over the study period. The BYOD subgroup also demonstrated a significant effect of engagement on medication adherence for number of application sessions (unstandardized regression coefficient beta=0.0006, p=0.02) and time spent therein (beta=0.00001, p=0.03). Study-provided phone users showed higher initial adherence rates, but greater decline (5.7%) than BYOD users (0.9%) over the study period. In-depth interviews revealed that participants preferred the BYOD model over using study-provided devices. ConclusionsResults indicate that the BYOD model is feasible in health research settings and improves participant experience, calling for further BYOD model validity assessment. Although group differences in medication adherence decline were insignificant, the greater trend of decline in provisioned device users warrants further investigation to determine if trends reach significance over time. Significantly higher application engagement rates and effect of engagement on medication adherence in the BYOD subgroup similarly imply that greater application engagement may correlate to better medication adherence over time.

The relationship of exposure to air pollutants in pregnancy with surrogate markers of endothelial dysfunction in umbilical cord

BackgroundThis study aims to investigate the association of exposure to ambient air pollution during pregnancy with cord blood concentrations of surrogate markers of endothelial dysfunction. MethodsThis population-based cohort was conducted from March 2014 to March 2015 among 250 mother-neonate pairs in urban areas of Isfahan, the second large and air-polluted city in Iran. We analyzed the association between the ambient carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), particular matter 10 (PM10), and air quality index (AQI) with cord blood levels of endothelin-1, vascular adhesion molecule (VCAM), and intercellular adhesion molecule (ICAM). Multiple regression analysis was conducted after adjustment for potential confounding factors and covariates. The regression coefficient (beta), standard error of the estimate (SE), and 95% confidence intervals for each regression coefficient (95% CI) are reported. ResultsData of 233 mother-neonate pairs were complete, and included in the analysis. Multiple regression analyses showed that AQI, CO and O3 had significant correlation with cord blood ICAM-1 [Beta (SE), 95%CI: 2.93 (0.72), 1.33,5.54; 2.28(1.44), 1.56,5.12; and 2.02(0.01), 1.03,2.04, respectively] as well as with VCAM-1 [2.78(0.91), 1.69,4.57; 2.47(1.47), 1.43,5.37; and 2.01(0.01),1.07,2.04, respectively]. AQI, PM10, and SO2 were significantly associated with Endothelin-1 concentrations [Beta (SE), 95%CI: 10.16(5.08),7.61,14.28; 9.70(3.46), 2.88,16.52; and 1.07(0.02), 1.03,2.11, respectively]. ConclusionsThe significant associations of air pollutants with markers of endothelial dysfunction during fetal period may provide another evidence on the adverse health effects of air pollutants on early stages of atherosclerosis from fetal period. Our findings underscore the importance of considering environmental factors in primordial prevention of chronic diseases.

Abstract 16047: Novel Association of Polymorphic Genetic Variants With Baseline PR Interval in Patients With Atrial Fibrillation: New Directions From a Prospective Study (DECAF)

Background: Prolongation of the PR interval in the electrocardiogram (ECG) is known to be associated with increased risk of atrial fibrillation (AF). We examined the association of selected single nucleotide polymorphisms (SNPs) with PR interval in AF patients. Methods: Four hundred AF patients undergoing catheter ablation were prospectively enrolled at our center. DNA extraction and genotyping for 16 AF-related SNPS from blood samples were performed using Qiagen QiaAMP kit and TaqMan assay respectively. A total of 371 DNA samples were available for genotyping. Multivariate linear regression analyses (after adjusting for age, gender, BMI, AF type) were applied to test allelic association (for minor allelic frequency) with baseline PR interval. PR interval duration in millisecond (ms) was derived from 12-lead ECGs recorded at the time of patient enrollment. Results: Three hundred seventy-one AF patients (67% male, 62±12 year, left atrial size 45.3±7 mm, 64% non-paroxysmal) undergoing catheter ablation were included in the analysis. Two SNPs, rs3807989 and rs7193343 were identified to have significant association with baseline PR interval. For rs3807989 (7q31), median [interquartile range] of PR interval durations were 174 (149-202), 169 (145-194), 162 (137-184) ms for AA, AG, GG (risk allele: A) respectively. The regression analysis for rs3807989 in a dominant model, showed significant allelic association (regression coefficient (beta) 9.8 [95% CI 1.58 to 18.02], p=0.019) with prolonged PR interval. For rs7193343, median [interquartile range] of PR interval durations were 169 (144-194), 162 (142-184), 154 (128-186) ms for CC, CT, TT (risk allele: T) respectively. When considering the effect of rs7193343 fitted with an additive model, significant inverse association with PR interval was observed (beta -7.4 [95% CI -14.23 to -2.63], p=0.032). Conclusion: We identified two novel genetic markers located near developmental genes CAV1 and ZFHX3 to be associated with PR interval; rs3807989 correlated directly with prolonged PR duration while rs7193343 demonstrated inverse correlation with the phenotype. Defining the etiology of this differential association will provide important insight into underlying AF mechanisms.

Idiosyncratic Noise Filtered (INF) Beta

Reliably estimating the beta of an individual stock has proved elusive. Individual stock price movements are a function of market/systematic movements and company specific/idiosyncratic movements. Since traditional beta estimation calculations make no attempt to minimize the impact of the idiosyncratic movements the beta regression coefficient will be fooled to best fit both the desired market based movements as well as the undesired idiosyncratic movements. If the idiosyncratic movements are not perfectly uncorrelated with market movements the regression beta will be inaccurate.We have developed a beta estimation model that appears to all but eliminate the idiosyncratic noise and statistical chance with other calculations of beta. Once we substantially improve individual stock beta estimates then we may not have to always rely on industry averages. Moreover even if we do rely on industry averages the industry averages will be more accurate and will require a far smaller sample.

Mindfulness, perceived stress, and subjective well-being: a correlational study in primary care health professionals.

BackgroundPrimary health care professionals (PHPs) usually report high levels of distress and burnout symptoms related to job strain. Mindfulness, defined as non-judgmental-present-moment awareness, seems to be a moderator in the causal association between life stressors and well-being. This study aimed to verify correlations among self-reported mindfulness, perceived stress (PS), and subjective well-being (SW) in Brazilian PHPs.MethodsWe performed a correlational cross-sectional study in a purposive sample of Brazilian PHPs (physicians, nurses, nursing assistants, and community health workers), working in community-oriented primary care programs (known locally as “Family Health Programs”). We used validated self-reporting instruments: the Mindful Attention Awareness Scale (MAAS), the Perceived Stress Scale (PSS), and the Subjective Well-being Scale (SWS). We performed a multivariate analysis of variance (MANOVA), through regression coefficients (beta) in relation to the professional category (nursing assistant), in addition to the length of time in the same job (under than 6 months) that had indicated the lowest level of PS.ResultsParticipants (n = 450) comprised community health workers (65.8 %), nursing assistants (18 %), registered nurses (10.0 %), and doctors (family physicians) (6.0 %); 94 % were female and 83.1 % had worked in the same position for more than one year. MANOVA regression analysis showed differences across professional categories and length of time in the same job position in relation to mindfulness, PS, and SW. Nurses demonstrated lower levels of mindfulness, higher PS, and SW negative affect, as well as lower SW positive affect. Being at work for 1 year or longer showed a clear association with higher PS and lower SW positive affect, and no significance with mindfulness levels. Pearson’s coefficient values indicated strong negative correlations between mindfulness and PS, and medium correlations between mindfulness and SW.ConclusionIn this study, there were clear correlations between mindfulness, PS, and SW across different primary care professional categories and time in the same job position, suggesting specific vulnerabilities that should be addressed through the development of staff awareness, stress prevention, and well-being interventions.

Effect of oral taurine on morbidity and mortality in elderly hip fracture patients: a randomized trial.

Hip fracture patients represent a large part of the elderly surgical population and face severe postoperative morbidity and excessive mortality compared to adult surgical hip fracture patients. Low antioxidant status and taurine deficiency is common in the elderly, and may negatively affect postoperative outcome. We hypothesized that taurine, an antioxidant, could improve clinical outcome in the elderly hip fracture patient. A double blind randomized, placebo controlled, clinical trial was conducted on elderly hip fracture patients. Supplementation started after admission and before surgery up to the sixth postoperative day. Markers of oxidative status were measured during hospitalization, and postoperative outcome was monitored for one year after surgery. Taurine supplementation did not improve in-hospital morbidity, medical comorbidities during the first year, or mortality during the first year. Taurine supplementation lowered postoperative oxidative stress, as shown by lower urinary 8-hydroxy-2-deoxyguanosine levels (Generalized estimating equations (GEE) analysis average difference over time; regression coefficient (Beta): −0.54; 95% CI: −1.08–−0.01; p = 0.04), blunted plasma malondialdehyde response (Beta: 1.58; 95% CI: 0.00–3.15; p = 0.05) and a trend towards lower lactate to pyruvate ratio (Beta: −1.10; 95% CI: −2.33–0.12; p = 0.08). We concluded that peri-operative taurine supplementation attenuated postoperative oxidative stress in elderly hip fracture patients, but did not improve postoperative morbidity and mortality.

WEB 2.0 AND ELECTIONS: A STUDY OF FACTORS INFLUENCING DIASPORA VOTERS ADOPTION OF E-VOTING SYSTEM

The ever growing number of Ghanaians living abroad and their contribution to the nation’s GDP has propelled the political debate of their voting rights. After formulating policies to enable them to exercise their franchise during elections, E-Voting/Internet Voting was one of the methods proposed to be used by diaspora Ghanaians to effectively exercise their right to vote. Thisresearch investigates and identifies the main determinants of E-Voting Adoption by eligible voters living ab road. A sample of 71 respondents from Malaysia, Singapore and USA has been used to collect the data. Regression and correlation analysis was conducted using SPSS 20. Regression beta coefficient and correlation coefficients were generated to test the hypotheses and to ascertain the effect of Information & Communication Technology, Political and Socio-demographical factors on adopting E-Voting System. The result shows strong linear relationship between some of the factors and E-Voting Adoption.

Effect of cycloplegia on the refractive status of children: the Shandong children eye study.

PurposeTo determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years.MethodsUsing a random cluster sampling in a cross-sectional school-based study design, children with an age of 4–18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops.ResultsOut of 6364 eligible children, data of 5999 (94.3%) children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4–18 years). Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF) was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D). In univariate analysis, DIFF decreased significantly with older age (P<0.001;correlation coefficient r:-0.24), more hyperopic non-cycloplegic refractive error (P<0.001;r = 0.13) and more hyperopic cycloplegic refractive error (P<0.001;r = 0.49). In multivariate analysis, higher DIFF was associated with higher cycloplegic refractive error (P<0.001; standardized regression coefficient beta:0.50; regression coefficient B: 0.19; 95% confidence interval (CI): 0.18, 0.20), followed by lower intraocular pressure (P<0.001; beta: -0.06; B: -0.02; 95%CI: -0.03, -0.01), rural region of habitation (P = 0.001; beta: -0.04; B: -0.07; 95%CI: -0.11, -0.03), and, to a minor degree, with age (P = 0.006; beta: 0.04; B: 0.009; 95%CI: 0.003, 0.016). 66.4% of all eyes with non-cycloplegic myopia (≤-0.50D) remained myopic after cycloplegia while the remaining 33.6% of eyes became emmetropic (18.0%) or hyperopic (15.7%) under cycloplegia. Prevalence of emmetropia decreased from 37.5% before cycloplegia to 19.8% after cycloplegia while the remaining eyes became hyperopic under cycloplegia.ConclusionsThe error committed by using non-cycloplegic versus cycloplegic refractometry in children with mid to dark-brown iris color decreased with older age, and in parallel manner, with more myopic cycloplegic refractive error. Non-cycloplegic refractometric measures lead to a misclassification of refractive error in a significant proportion of children.

Osteoarthritis medical labelling and health-related quality of life in the general population.

BackgroundOsteoarthritis is the most common chronic joint disease. In the absence of an effective medical treatment and due to the chronic nature of this condition, an osteoarthritis medical diagnosis may finally result in decreased health-related quality of life. Therefore, the aim of this study was to measure the impact of the osteoarthritis medical labelling on physical and mental health-related quality of life.MethodsSubjects (n = 1132, 58.7% women) were approached as participants of an urban population-based cohort (EPIPorto). Self-reported information on previous diagnosis of knee, hip or hand osteoarthritis was obtained and rheumatologists established knee, hip or hand osteoarthritis clinical diagnosis in symptomatic individuals. Physical and mental dimensions of health-related quality of life were evaluated using the self-administered Medical Outcomes Study: 36-Item Short Form Survey. Crude and adjusted linear regression coefficients (beta) and the corresponding 95% confidence intervals (95% CI) were computed to estimate the associations between being labelled as an osteoarthritis case and health-related quality of life.ResultsRegardless of disease medical labelling, individuals with osteoarthritis scored significantly lower physical health-related quality of life when compared to those without joint disease (kneeunexposed: beta = −5.3, 95% CI: −7.6, −3.1; kneeexposed: beta = −6.0, 95% CI: −8.4, −3.7; hipunexposed: beta = −6.0, 95% CI: −9.8, −2.3; hipexposed: beta = −11.0, 95% CI: −15.6, −6.4; handunexposed: beta = −4.3, 95% CI: −6.5, −2.0; handexposed: beta = −4.3, 95% CI: −6.6, −2.1). The same was not observed regarding mental health-related quality of life. Among subjects with clinically confirmed osteoarthritis, the medical labelling of this joint disease was not significantly associated to health-related quality of life.ConclusionsThe labelling of knee, hip and hand osteoarthritis diagnosis may not add specific benefit to osteoarthritis patients in terms of its capability to improve health-related quality of life.

Heterogeneity of ventricular repolarization in newborns with intrauterine growth restriction

BackgroundIntrauterine growth restriction (IUGR) is associated with structural and functional cardiac alterations but the electrophysiological consequences of these disturbances remain unknown. AimsTo explore the distribution of ventricular repolarization and its relation to myocardial mechanics in newborns with IUGR. Study design, subjects and outcome measurementsConventional and tissue Doppler echocardiographic data, and electrocardiographic parameters used to describe the distribution of ventricular repolarization (dispersion of QT [QTd] and JT [JTd]), were obtained on the second (D2) and fifth (D5) postnatal day and compared between 25 IUGR newborns and 25 matched-for-gestational age controls. ResultsIUGR was associated with relative interventricular septum hypertrophy, increased left ventricular (LV) E/E′ ratio and higher LV myocardial performance index (MPI). On both study days, the IUGR infants presented higher QTd and JTd compared to controls (QTd-D2: 66±20ms vs. 36±12ms, P<0.001; JTd-D2: 54±13ms vs. 34±9ms, P<0.001; QTd-D5: 61±14ms vs. 27±12ms, P<0.001; JTd-D5: 54±13ms vs. 27±9ms, P<0.001). The association between QTd and LV E/E′ (D2: regression coefficient beta 0.747, R2 0.585; D5: beta 0.843, R2 0.646) and QTd and MPI (D2: beta 0.680, R2 0.576; D5: beta 0.698, R2 0.650) was also significant (P<0.001 for all analyses). ConclusionsOur findings suggest that IUGR is associated with electrophysiological remodeling of the neonatal heart, a process which is closely related to the underlying alterations in ventricular mechanics and might predispose to adverse electrophysiological events.

Distance-based beta regression for prediction of mutual funds

In the context of regression with a beta-type response variable, we propose a new method that links two methodologies: a distance-based model, and a beta regression with variable dispersion. The proposed model is useful for those situations where the response variable is a rate, a proportion or parts per million, and this variable is related to a mixture of continuous and categorical explanatory variables. We present the main statistical properties and several measures for selection of the most predictive dimensions for the model. In our proposal we only need to choose a suitable distance for both the mean model and the variable dispersion model depending on the type of explanatory variables. The mean and precision predictions for a new individual, and the problem of missing data are also developed. Rather than removing variables or observations with missing data, we use the distance-based method to work with all data without the need to fill in or impute missing values. Finally, an application of mutual funds is presented using the Gower distance for both the mean model and the variable dispersion model. This methodology is applicable to any problem where estimation of distance-based beta regression coefficients for correlated explanatory variables is of interest.

Quality of life, depression, and sexual dysfunction in spouses of female patients with fibromyalgia

The aim of this study was to investigate the effects of the quality of life and psychological condition of female patients with fibromyalgia and their spouses on sexual function. A total of 32 female patients diagnosed with fibromyalgia and their spouses were analyzed. Thirty married couples were included in the study as the control group. The demographic data of the fibromyalgia patients were recorded, a visual analog scale was used to evaluate the level of pain, and the Fibromyalgia Impact Questionnaire was used to evaluate the impact of the symptoms on the quality of life of the patients. The quality of life of both the patients and the control group were evaluated using the Short Form 36 (SF-36), and psychological variables were evaluated using the Beck Depression Inventory (BDI) and Beck Anxiety Inventory. Sexual function was assessed using the Female Sexual Function Index for female participants and the International Index of Erectile Function (IIEF) for male participants. The IIEF erectile dysfunction scores were significantly lower in the spouses of female patients with fibromyalgia than in the control group (p < 0.05), and the BDI scores were significantly higher in the spouses of the female patients with fibromyalgia (p < 0.05). Among the SF-36 scores, the emotional and physical roles were significantly lower in the spouses of the female patients with fibromyalgia (p = 0.003 and p = 0.004, respectively). In all spouses of FMS patients and controls, there was a significantly negative correlation between erectile function, the BDI score, and to be married with FMS patient and positive correlations between erectile function and emotional role, social function, mental health, SF-36 pain score, and general health (p < 0.05 for all). In a linear regression model, BDI, to be married with FMS patient and general health were found to affect erectile function (beta regression coefficient = -0.572, SE = 0.082, p = 0.001; beta regression coefficient = -0.332, SE = 1.619, p = 0.007; beta regression coefficient = 0.445, SE = 0.065, p = 0.005, respectively). Being a spouse of a patient with fibromyalgia might significantly interfere with quality of life and lead to a high rate of sexual dysfunction. Spouses of patients with fibromyalgia might also be investigated for sexual dysfunction and quality of life. Treatment programs for this group should be considered.

Genetic variants of homocysteine metabolism and multiple sclerosis: A case–control study

Methylenetetrahydrofolate reductase (MTHFR) is necessary for the synthesis of methionine and S-adenosylmethionine, which is necessary for CNS (re-)myelination. The MTHFR variant c.1298A>C was associated with the development of relapsing remitting multiple sclerosis (RRMS) in a German population. This study aimed at analyzing whether further genetic variants of methionine metabolism are associated with the development or the clinical course of RRMS. Therefore, genomic DNA of 147 serial German RRMS patients and 147 matched healthy controls was genotyped for five polymorphic variants of methionine metabolism. Statistical analyses were performed using multivariate binary and linear regression analyses. We show that the insertion allele of cystathionine beta-synthase (CBS) c.844_855ins68bp and the G-allele of reduced folate carrier 1 (RFC1) c.80G>A were associated with an earlier age of onset of MS, suggesting gene-dose effects (median age of onset in years: 25-26-32; standardized regression coefficient beta: 0.216; p=0.030, and 29-31-35 years; beta: 0.282; p=0.005, respectively). Conclusively, mutant variants of CBS and RFC1 may be associated with the age of RRMS onset. Since methionine metabolism can be manipulated by supplementation of vitamins and amino acids, our data provide a rationale for novel ideas of preventive and therapeutic strategies in RRMS.