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Responsiveness to change in health-related quality of life in a randomized clinical trial: a comparison of the Prostate Cancer Specific Quality of Life Instrument (PROSQOLI) with analogous scales from the EORTC QLQ-C30 and a trial specific module. European Organization for Research and Treatment of Cancer.

INTRODUCTION: The Prostate Cancer Specific Quality of Life Instrument (PROSQOLI) was developed to be a pragmatic outcome measure for clinical trials in symptomatic men with advanced hormone-resistant prostate cancer. DESIGN AND SETTING: A comparative assessment of responsiveness was made with longitudinal data from a positive multicenter randomized trial of palliative chemotherapy in 161 symptomatic men with advanced hormone-resistant prostate cancer. INSTRUMENTS: The PROSQOLI, the European Organisation for Research and Treatment of Cancer (EORTC) core quality of life questionnaire (QLQ-C30), and a specific quality of life module for advanced prostate cancer [QLM-P14] were administered every 3 weeks while patients received their allocated treatment. FINDINGS: Sixteen of the 19 health-related quality of life (HRQL) scales demonstrated improvements in palliative responders. All three pain scales detected a beneficial effect of palliative chemotherapy. The relative efficiency statistics favored the PROSQOLI for physical symptoms and physical function but the QLQ-C30 for emotional function, social function, and global perceptions. The PROSQOLI linear analog scale was the most responsive measure of pain. Bootstrap confidence intervals for the relative efficiency statistics were wide. CONCLUSIONS: Both the PROSQOLI and the analogous scales from the QLQ-C30 were responsive to improvements in HRQL. Differences between the instruments were generally subtle. The PROSQOLI is a short, simple, responsive measure of HRQL in men receiving systemic treatment for advanced hormone-resistant prostate cancer.

Aged↗

Quality of life and impairment in patients with multiple sclerosis.

OBJECTIVES: The aims of this study were to describe the quality of life in patients with multiple sclerosis (MS) given immunological treatment and in those not given immunological treatment and to investigate the relationship between impairment and quality of life. METHODS: Twenty nine patients given immunological treatment were matched with the same number of patients not given such treatment. Matching variables were sex, Kurtzke's Expanded Disability Status Scale (EDSS), years since diagnosis, and age (total n = 58). The patients were interviewed using the self-reported impairment checklist and they answered two questionnaires on quality of life, the 36-Item Short-Form Health Survey (SF-36) and the Subjective Estimation of Quality of Life (SQoL). RESULTS: The self-reported impairment checklist captured a more differentiated picture of the patients' symptoms of MS than the EDSS. Health related quality of life was markedly reduced, while the subjective quality of life was less affected. There was a stronger association between self-reported ratings of impairment and health related quality of life on the SF-36 than between impairment and global ratings of quality of life on the SQoL. Subjective quality of life on the SQoL was not directly dependent on impairment expressed in physical limitations. There were no statistically significant differences between the treated and untreated groups. A non-significant trend towards better health related quality of life was found in favour of the treated group with respect to emotional role, physical role, and social function on the SF-36. CONCLUSIONS: The self-reported impairment checklist and SF-36 proved to be valuable complements to the well established EDSS in describing the diverse symptoms of MS. Measuring both health related quality of life and subjective wellbeing provides valuable knowledge about the consequences of MS.

Activities of Daily Living↗

Statistical analysis of data pertaining to complex state systems by stepwise regression with reformulated parameters; application to spectroscopically monitored hemoglobin oxygen binding data.

A method is described for the statistical analysis of data pertaining to complex state systems, based on the concept of reformulating the parameters describing the system as a hierarchy of interactions, and this method demonstrated on the analysis of spectroscopically monitored hemoglobin oxygen binding data [K. Imai, Biophys. Chem. 37 (1990) 197-210]. The concept of reformulation was first extended to state parameters other than delta G degree s, such as the extinction coefficients (epsilon s) associated with different ligation states during hemoglobin oxygen binding. The reformulated parameters are incrementally allowed to vary in the data fitting procedure, and the statistical significance of the added parameters tested by F and Kolmogorov-Smirnov tests. The result of this method is the minimal set of statistically significant parameters required to describe the data. The hierarchical nature of reformulated parameters allows the physical significance of the subset of statistically significant parameters to be discussed even when all reformulated terms may not be statistically significant. Applying this method to hemoglobin oxygen binding data with the reformulated Adair model demonstrated that at least two, and at most three, of the four reformulated Adair constants are statistically significant. A reformulated square model was found to give a statistically indistinguishable fit from the Adair model, with the statistically significant thermodynamic terms essentially those proposed by Linus Pauling in 1935. A change in delta epsilon with subsequent oxygen binding events was found to be significant in both models. These results are consistent with a model for hemoglobin oxygen binding where a subunit changes its conformation upon oxygen binding, and affects the conformation of adjacent subunits.

Data Interpretation, Statistical↗

[Atmospheric pollution and spirometry in healthy children of the Distrito Federal].

Investigation of the vital capacity, maximum expiratory flow and maximum mean expiratory flow was carried out in children living in two areas of Mexico City, one of them with a high degree (azcapotzalco) and the other one with low degree (Tizapán) of air pollution. Timed spirometry was carried out on children attending 4th, 5th and 6th grades in two official grammar schools so both groups were as uniform as possible in their social-economical level and nutritional and health conditions. This goal was attained quite satisfactorily and groups turned similar, after comparing results and analysing statistically somatometric data, together with scholarship of the parents, economical income, history of respiratory diseases and physical examination. However, quite a significant statistical difference (p less than 0.001) was found between the parameters involving measurements of ventilation in favor of Tizapán children. The difference between Azcapotzalco and Tizapán children in terms of the three ventilatory parameters analyzed was possibly due to the fact the former lived in a greater polluted area.

Air Pollution↗

Complexity quantification of dense array EEG using sample entropy analysis.

In this paper, a time series complexity analysis of dense array electroencephalogram signals is carried out using the recently introduced Sample Entropy (SampEn) measure. This statistic quantifies the regularity in signals recorded from systems that can vary from the purely deterministic to purely stochastic realm. The present analysis is conducted with an objective of gaining insight into complexity variations related to changing brain dynamics for EEG recorded from the three cases of passive, eyes closed condition, a mental arithmetic task and the same mental task carried out after a physical exertion task. It is observed that the statistic is a robust quantifier of complexity suited for short physiological signals such as the EEG and it points to the specific brain regions that exhibit lowered complexity during the mental task state as compared to a passive, relaxed state. In the case of mental tasks carried out before and after the performance of a physical exercise, the statistic can detect the variations brought in by the intermediate fatigue inducing exercise period. This enhances its utility in detecting subtle changes in the brain state that can find wider scope for applications in EEG based brain studies.

Adult↗

[Blood pressure variation in relation to distinct physical activity levels in young people and adults].

In order to prove the existence of a relationship between the degree of physical activity and blood pressure, we studied 200 persons divided in two groups (first group less than 30 years old; second group greater than 30 years old), evaluating the habitual physical activity, stratifying them into different categories according to this activity. We did not find any significant statistical differences between the blood pressure and the various physical activity categories. However, there were statistically significant differences in the same group related to sex and age. Our results suggest that physical activity is not clearly related to blood despite the fact that these are both considered cardiovascular disease risk factors.

Adolescent↗

Spline methods for the comparison of physical and genetic maps.

The first genetic maps were constructed by linkage analysis. Physical mapping techniques, such as radiation hybrids and complete sequencing, produce a different picture. For the purposes of population genetics, clinical genetics, and genetic epidemiology, it is important to harmonize and amalgamate existing genetic and physical maps. Among other things, comparisons of the two kinds of maps promotes better understanding of the wide variation in local recombination rates per unit physical length of DNA. The current paper presents methods for estimating recombination intensity as a function of physical distance along a chromosome. Genetic map distance is the integral of intensity. We derive fast reliable estimation algorithms based on a Poisson process model, penalized likelihoods, and cubic spline interpolation. Our methods provide a rigorous and statistically sound foundation for comparing physical and genetic maps. To illustrate the possibilities, we apply the methods to published recombination data on CEPH families and the complete sequences of chromosomes 21 and 22. Our results are in good agreement with previous studies and the biological data.

Algorithms↗

The clenching-grinding spectrum and fear circuitry disorders: clinical insights from the neuroscience/paleoanthropology interface.

This review discusses the clenching-grinding spectrum from the neuropsychiatric/neuroevolutionary perspective. In neuropsychiatry, signs of jaw clenching may be a useful objective marker for detecting or substantiating a self-report of current subjective emotional distress. Similarly, accelerated tooth wear may be an objective clinical sign for detecting, or substantiating, long-lasting anxiety. Clenching-grinding behaviors affect at least 8 percent of the population. We argue that during the early paleolithic environment of evolutionary adaptedness, jaw clenching was an adaptive trait because it rapidly strengthened the masseter and temporalis muscles, enabling a stronger, deeper and therefore more lethal bite in expectation of conflict (warfare) with conspecifics. Similarly, sharper incisors produced by teeth grinding may have served as weaponry during early human combat. We posit that alleles predisposing to fear-induced clenching-grinding were evolutionarily conserved in the human clade (lineage) since they remained adaptive for anatomically and mitochondrially modern humans (Homo sapiens) well into the mid-paleolithic. Clenching-grinding, sleep bruxism, myofacial pain, craniomaxillofacial musculoskeletal pain, temporomandibular disorders, oro-facial pain, and the fibromyalgia/chronic fatigue spectrum disorders are linked. A 2003 Cochrane meta-analysis concluded that dental procedures for the above spectrum disorders are not evidence based. There is a need for early detection of clenching-grinding in anxiety disorder clinics and for research into science-based interventions. Finally, research needs to examine the possible utility of incorporating physical signs into Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition posttraumatic stress disorder diagnostic criteria. One of the diagnostic criterion that may need to undergo a revision in Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition is Criterion D (persistent fear-circuitry activation not present before the trauma). Grinding-induced incisor wear, and clenching-induced palpable masseter tenderness may be examples of such objective physical signs of persistent fear-circuitry activation (posttraumatic stress disorder Criterion D).

Anthropology↗

Physical inactivity and glucose intolerance in the multiethnic island of Mauritius.

The island nation of Mauritius, located in the southwest Indian Ocean, has a high prevalence of non-insulin-dependent diabetes mellitus (NIDDM) among all of its ethnic groups (Hindu and Muslim Indians, African-origin Creoles, and Chinese). These high rates of NIDDM among groups of varying genetic background provide strong support for the importance of environmental components in the etiology of the disease. Research in Mauritius using a simple activity scale has suggested that physical inactivity may be one of these components. The current investigation further examined the association between glucose tolerance and physical activity in middle-aged nondiabetic residents of Mauritius using a more extensive physical activity questionnaire (the Modifiable Activity Questionnaire). Excluding individuals with NIDDM, a statistically significant (P < 0.05) inverse relationship between physical activity and 2-h post-load glucose concentration was found for both males (rho = -0.14) and females (rho = -0.11). Stratifying by ethnic group, similar inverse correlations were observed in Hindu, Creole, and Chinese males, and in Hindu females (P < 0.05), as well as weaker relationships in Muslim males and Creole females (P < 0.10). Total physical activity remained an independent predictor of 2-h post-load glucose concentration after controlling for body mass index, waist-hip ratio, age, and family history of NIDDM. These data are supportive of a potentially important role of physical activity in the prevention of NIDDM in middle-aged inhabitants of Mauritius.

Adult↗

Comorbidity of depression with chronic facial pain and temporomandibular disorders.

OBJECTIVE: The objective of this study was to examine the comorbidity of depressive disorders in patients with chronic facial pain presenting to a multidisciplinary facial pain clinic. STUDY DESIGN: Data were collected from 72 consecutive patients with chronic facial pain who had received a maltidisciplinary evaluation including a psychiatric examination for the presence of depressive disorders. RESULTS: Twenty-eight percent of patients met criteria of the latest Diagnostic and Statistical Manual of Mental Disorders for major depression, and 25% met the criteria for minor depression. A further 22% reported subsyndromal depressive symptoms. Temporomandibular disorders were demonstrable in 71% of these patients, but the remaining 29% had no objective physical findings. There was no statistical difference in comorbidity of depressive disorders in patients with temporomandibular disorders compared with patients without temporomandibular disorders. CONCLUSION: Screening for symptoms of depression should be an integral part of the evaluation of all patients with chronic facial pain, even when masticatory muscle or temporomandibular joint disorders are identified.

Adolescent↗

Health status in rheumatoid arthritis: cross cultural evaluation of a Portuguese version of the Arthritis Impact Measurement Scales 2 (BRASIL-AIMS2).

OBJECTIVE: To develop a Portuguese version of the Arthritis Impact Measurement Scales 2 (AIMS2) and to evaluate its measurement properties in Brazilian patients with rheumatoid arthritis (RA). METHODS: The BRASIL-AIMS2 was developed through the stages of initial translation, back translation, definition of the first Portuguese version, and committee review. Convergent validity was determined by administering the questionnaire to 32 patients with RA and correlating it with several clinical and laboratory variables. Twenty-five of the 32 patients were interviewed 3 times to evaluate test-retest and interobserver reliability. RESULTS: Six translated questions were replaced due to the lack of cultural equivalence. The mean time of administering the questionnaire was about 30 minutes. The test-retest and interobserver reliability were satisfactory, except for Health Perception, and correlation coefficients ranged from 0.87 to 0.98. The Physical, Symptom, and Role components were statistically correlated with Health Assessment Questionnaire, functional class, morning stiffness, and physician assessed disease activity. CONCLUSION: The Physical, Symptom, and Role subscales of the BRASIL-AIMS2 may be useful in the evaluation of quality of life in Brazilian patients with RA.

Adult↗

Efficacy of tacrolimus in rheumatoid arthritis patients who have been treated unsuccessfully with methotrexate: a six-month, double-blind, randomized, dose-ranging study.

OBJECTIVE: To assess the efficacy, safety, and optimal dose of tacrolimus monotherapy in patients with rheumatoid arthritis (RA). METHODS: This phase II, randomized, double-blind, placebo-controlled monotherapy study was set in 12 community sites and 9 university-based sites. Two hundred sixty-eight patients with RA who were resistant to or intolerant of methotrexate (mean dose 15.2 mg/week) and had active disease for at least 6 months (mean tender joint count 28.2, mean erythrocyte sedimentation rate 46.5 mm/hour) were randomized to receive treatment after discontinuation of methotrexate. Those who received at least 1 dose of tacrolimus were analyzed; 141 completed the study. Stable dosages of nonsteroidal antiinflammatory drugs and low-dose prednisone were allowed during treatment. All patients were given 1, 3, or 5 mg of tacrolimus or placebo once daily for 24 weeks. The American College of Rheumatology definition of 20% improvement (ACR20) and the tender and swollen joint counts at the end of treatment were the primary outcomes. RESULTS: ACR20 response rates demonstrated a clear dose response. The ACR20 response was observed in 15.5% of patients receiving placebo (95% confidence interval [95% CI] 7.1-23.9%), 29% of the 1 mg tacrolimus group (95% CI 18.3-39.7%) (P < 0.058); 34.4% of the 3 mg group (95% CI 22.7-46.0%) (P < 0.013), and 50% of the 5 mg group (95% CI 37.8-62.3%) (P < or = 0.001). The tender joint count improved statistically significantly in all tacrolimus groups. The swollen joint count, physical function, and patient-assessed pain improved statistically significantly in the 3 mg and 5 mg groups. The incidence of creatinine elevation > or =40% above baseline levels increased in a dose-dependent manner. Dropout rates were high (41-59%) and were more common for inefficacy in the placebo patients (71.4%), whereas they were more common for toxicity in the high-dose tacrolimus groups (31-33%). Discontinuation for creatinine elevation occurred in the 3 mg (3.1%) and 5 mg (10.9%) tacrolimus groups. CONCLUSION: Tacrolimus improved disease activity in methotrexate-resistant or -intolerant patients with RA. A dose response was observed when efficacy and toxicity were assessed at different doses. The optimal dose of tacrolimus appears to be >1 mg but < or=3 mg daily.

Anti-Inflammatory Agents, Non-Steroidal↗

Racial and Ethnic Approaches to Community Health (REACH) Detroit partnership: improving diabetes-related outcomes among African American and Latino adults.

OBJECTIVES: We sought to determine the effects of a community-based, culturally tailored diabetes lifestyle intervention on risk factors for diabetes complications among African Americans and Latinos with type 2 diabetes. METHODS: One hundred fifty-one African American and Latino adults with diabetes were recruited from 3 health care systems in Detroit, Michigan, to participate in the Racial and Ethnic Approaches to Community Health (REACH) Detroit Partnership diabetes lifestyle intervention. The curriculum, delivered by trained community residents, was aimed at improving dietary, physical activity, and diabetes self-care behaviors. Baseline and postintervention levels of diabetes-specific quality-of-life, diet, physical activity, self-care knowledge and behaviors, and hemoglobin A1C were assessed. RESULTS: There were statistically significant improvements in postintervention dietary knowledge and behaviors and physical activity knowledge. A statistically significant improvement in A1C level was achieved among REACH Detroit program participants (P<.0001) compared with a group of patients with diabetes in the same health care system in which no significant changes were observed (P=.160). CONCLUSIONS: A culturally tailored diabetes lifestyle intervention delivered by trained community residents produced significant improvement in dietary and diabetes self-care related knowledge and behaviors as well as important metabolic improvements.

Adolescent↗