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Medically incongruent chronic back pain: physical limitations, suffering, and ineffective coping.

Chronic low back pain (CLBP) patients with pain and symptomatology incongruent with physical pathology have been found to have a poorer outcome to medical treatment and rehabilitation, and to use health care resources excessively. To examine possible psychological and behavioral bases for this pattern, this investigation contrasted 40 CLBP patients who displayed non-organic physical signs, inappropriate symptoms, and/or anatomically incongruent pain drawings with 40 'control' CLBP patients without incongruent pain criteria. Multivariate analyses revealed that the incongruent CLBP group reported greater pain intensity and depression, received higher observer ratings of pain, displayed more ambulatory/postural pain behavior, and reported more dysfunctional cognitions during pain. Incongruent CLBP patients also were found to have greater physical impairment and disability. When group differences on physical impairment/disability were controlled statistically, all the afore-mentioned differences disappeared, with one exception. Incongruent CLBP patients still displayed more maladaptive and dysfunctional cognitions. These findings indicate that incongruent CLBP patients may be conceptualized as ineffective and overwhelmed in their attempts to cope and as more physically disabled as a result of their pain. The role of cognitive factors, reasons for failure of physically based interventions, and implications for patient management are discussed.

Adaptation, Psychological↗

Emergence of sex differences in prevalence of high systolic blood pressure: analysis of a longitudinal adolescent cohort.

BACKGROUND: High systolic blood pressure (SBP) occurs more frequently both among men and boys than among women and girls. No longitudinal study has investigated whether the impact of SBP determinants differ according to sex in youth. METHODS AND RESULTS: Between 1999 and 2005, an adolescent cohort (n=1267) completed a questionnaire survey and underwent biannual blood pressure and anthropometric assessment (grades 7, 9, and 11). Boys accounted for approximately 50% of those with high SBP at grade 7 and 9 assessments but 67% of those with high SBP at the grade 11 assessment. As computed through a generalized estimating equations logistic regression model (sex, age, sex and age interaction term, overweight, physical activity, sedentary behavior, heart rate, household income, tobacco use, and 4 language categories), the likelihood of high SBP values among boys compared with girls was 1.29 (95% CI, 0.77 to 2.16) in grade 7, 1.98 (95% CI, 1.35 to 2.93) in grade 9, and 2.74 (95% CI, 1.52 to 4.94) in grade 11. Although there was a significant interaction between sex and age, interaction terms of sex with overweight, sedentary behavior, and physical activity were not statistically significant. Overweight (odds ratio [OR], 2.63; 95% CI, 1.76 to 3.92) and sedentary behavior (OR, 1.17 for increment of 5 hours weekly; 95% CI 1.04 to 1.33) demonstrated positive associations with high SBP values. Physical activity was inversely associated with the presence of high SBP (OR, 0.92 for increment of 5 activities in 7 days; 95% CI, 0.84 to 1.00). CONCLUSIONS: Boys are more likely than girls to develop high SBP as they approach adulthood. Even among overweight adolescents, reducing sedentary behavior and increasing physical activity may lower the risk of high SBP.

Adolescent↗

Expressive writing for high-risk drug dependent patients in a primary care clinic: a pilot study.

BACKGROUND: Previous research has shown that expressive writing is beneficial in terms of both physical and emotional health outcomes. This study aimed to investigate the effectiveness and acceptability of a brief expressive writing intervention for high-risk drug dependent patients in a primary care clinic, and to determine the relationship between linguistic features of writing and health outcomes. METHODS: Participants completed four 15-minute expressive writing tasks over a week, in which they described their thoughts and feelings about a recent stressful event. Self-report measures of physical (SF-12) and psychological health (DASS-21) were administered at baseline and at a two-week follow-up. Fifty-three participants were recruited and 14 (26%) completed all measures. RESULTS: No statistically significant benefits in physical or psychological health were found, although all outcomes changed in the direction of improvement. The intervention was well-received and was rated as beneficial by participants. The use of more positive emotion words in writing was associated with improvements in depression and stress, and flexibility in first person pronoun use was associated with improvements in anxiety. Increasing use of cognitive process words was associated with worsening depressive mood. CONCLUSION: Although no significant benefits in physical and psychological health were found, improvements in psychological wellbeing were associated with certain writing styles and expressive writing was deemed acceptable by high-risk drug dependent patients. Given the difficulties in implementing psychosocial interventions in this population, further research using a larger sample is warranted.

Journal Article↗

Risk of physical abuse to children of spouse abusing parents.

The purpose of this study is to estimate the gender-specific probability of a violent spouse also physically abusing his or her child within a representative sample. The study is based on a sample of 3,363 American parents interviewed for the 1985 National Family Violence Survey. The study shows that marital violence is a statistically significant predictor of physical child abuse. The greater the amount of violence against a spouse, the greater the probability of physical child abuse by the physically aggressive spouse. This relationship is stronger for husbands than for wives. The probability of child abuse by a violent husband increases from 5% with one act of marital violence to near certainty with 50 or more acts of marital violence. The predicted probability of child abuse by a violent wife increases from 5% with one act of marital violence to 30% with 50 or more acts of marital violence. Implications for divorce custody proceedings are discussed.

Adolescent↗

The use of analgesics in patients with acute abdominal pain.

Analgesics in patients with acute abdominal pain are often withheld for fear that they may change physical examination findings and thus may be unsafe. We conducted a randomized, prospective, placebo-controlled trial to investigate changes in physical examination following the administration of placebo, 5 mg, or 10 mg of morphine to 49 patients with acute abdominal pain. One patient was withdrawn secondary to inadequate documentation. Of the 48 patients who completed the trial, a statistically significant change in physical examination was noted in both groups receiving analgesics, but not in the placebo group. No adverse events or delays in diagnosis were attributed to the administration of analgesics. We conclude that physical examination does change after the administration of analgesics in patients with acute abdominal pain and that a larger study is needed to evaluate analgesic safety in this subpopulation of emergency department patients.

Abdominal Pain↗

Physical activity and incidence of diabetes: the Honolulu Heart Program.

Few prospective studies have assessed the relation between physical activity and diabetes. The authors examined this relation prospectively among 6,815 Japanese-American men in the Honolulu Heart Program who were aged 45-68 years and initially free of diagnosed diabetes in 1965-1968. A physical activity index was calculated based on time spent per day in different activity levels and a weighting factor correlated with estimated oxygen consumption. Incidence of clinically recognized diabetes was based on self-reported use of diabetic medication at one of two subsequent examinations. The age-adjusted 6-year cumulative incidence of diabetes decreased progressively with increasing quintile of physical activity from 73.8 to 34.3 per 1,000 (p < 0.0001, trend) in all men and from 53.9 to 21.7 per 1,000 (p < 0.0001, trend) among men with a non-fasting glucose level < 225 mg/dl one hour after a 50-gm load, the latter group being less likely to have unrecognized diabetes at baseline. When stratified by tertile of baseline glucose, trends in incidence across physical activity quintiles were statistically significant in the low and middle tertiles but not in the high tertile. Similar inverse trends were observed for men in the lower four quintiles of body mass index, however, these trends were weaker and not significant for men in the upper quintile of body mass index. Age-adjusted odds ratios for diabetes comparing the upper with the lower four quintiles of physical activity were 0.55 (95% confidence interval (CI) 0.41-0.75) for all men and 0.50 (95% CI 0.33-0.74) for men with glucose < 225 mg/dl. After adjustment for age, body mass index, subscapular/triceps skinfold ratio, systolic blood pressure, triglycerides, glucose, hematocrit, and parental history of diabetes, odds ratios were still statistically significant and similar in magnitude. Restriction of analyses to men who remained free of cardiovascular disease during the study period produced similar results, which suggests that inactivity due to subclinical cardiovascular disease is unlikely to be responsible for these findings. Risk factor-adjusted odds ratios for older men (55-68 years) demonstrated that physical activity confers at least the same degree of protection as in younger men (45-54 years). These results indicate that physical activity is associated inversely with incident diabetes and that the beneficial effect does not appear to be mediated through improvements in other risk factors assessed in this study.

Age Factors↗

Physical properties of dental silver-tin amalgams with high and low copper contents.

Newly developed amalgams such as Tytin, Sybraloy, and Dispersalloy had low static creep, high compressive strength, and similar values for both diametral tensile strength and dimensional change in comparison with conventional amalgams such as Kerr Spheraloy, Caulk Spherical, Shofu Spherical, and Caulk 20th Century Micro Cut. The data for physical properties were evaluated statistically, and the amalgams were ranked according to the numerical position assigned to each property.

American Dental Association↗

Usefulness of cephalometry in sparing polysomnography of patients with suspected obstructive sleep apnea.

The aim of this investigation was to evaluate the contribution of cephalometry to a statistical model integrating clinical, physical, and oximetric variables, to reduce demands for polysomnographies. Two hundred and twenty-five consecutive patients that had been referred to the sleep clinic for suspected obstructive sleep apnea (OSA) were studied. The clinical assessment of all patients consisted of a sleep related questionnaire, the Epworth sleepiness scale, and a physical examination. In addition, they all underwent spirometry, cephalometry, and a full polysomnography. The clinical variables related with OSA were questions concerning witnessing of apneas by bed partners, intensity of snoring, a history of hypertension, and nocturia. A significant relation was also found with score on the Epworth scale, sex, age, body mass index, neck and waist circumferences, total number and frequency of oxygen desaturations, and the lowest oxygen saturation value. Significant cephalometric measurements were: the linear distance from gonion to gnathion, from the hyoid bone to the mandibular plane, and from the posterior nasal spine to the tip of the soft palate, and the thickness of the uvula as well. A statistical model was built to estimate a patient's probability of having OSA based on clinical variables, physical examination, pulse oximetry, and cephalometry. The validation of this model demonstrated a remarkable ability in reducing the number of polysomnographic studies. We conclude that cephalometry combined with clinical variables, physical examination, and nocturnal oximetry is useful in the diagnosis of OSA and enables the sparing of a considerable number of polysomnographies.

Adult↗

Weather conditions and spinal patients.

STUDY DESIGN: A retrospective study. OBJECTIVES: To evaluate the effects of various weather conditions on reported health status. SUMMARY OF BACKGROUND DATA: Existing literature shows no definite conclusions regarding the effect of weather on patients with spinal pathology. METHODS: Initial visit data from 23 American centers participating in the National Spine Network included demographic information and SF-36-based health status. Weather conditions when and where patients were seen were obtained from the National Climatic Data Center and U.S. Naval Observatory. SF-36 outcomes were predicted using multiple regression techniques from weather parameters, which included high and low temperature, average dew point, wet bulb, barometric pressure, total precipitation, phase of the moon, and length of sunlight. RESULTS: A total of 26,862 of 54,062 patients were identified. Two models were compared: model 1 included the above weather predictors and model 2 added age and gender. For each SF-36 scale and subscale and the Physical and Mental composite Scores, both models were statistically significant, although only model 2 for physical function produced an R value greater than 1%. Barometric pressure was the only weather predictor that was consistently significant. Increased pressure was associated with worse outcomes. Although age and gender were significant additions to the prediction equation, overall, the practical contribution was minimal. CONCLUSION: A statistically significant relationship between weather factors and SF-36-based health status exists but has minimal clinical significance. These factors had minimal if any effect on mental health-related scores bringing into question either the relationship between weather and psychological status, at least in patients with spinal problems or the usefulness of the instrument used.

Female↗

Estimating physical distances from radiation hybrid mapping data.

Radiation hybrid mapping has become an established tool for building physical maps. It represents a powerful way of constructing YAC contigs and high-resolution maps for positional cloning experiments. Ideally, radiation hybrids should not only provide support for the true order of the markers, but also accurate estimates of the physical distances between them. Statistical analysis of radiation hybrids has proved difficult because of the number of parameters (representing the fragment retention probabilities) that must be estimated, and simplifying assumptions are needed to analyze large numbers of markers simultaneously. The ramifications of these assumptions for the calculation of physical distances are investigated. A simple two-locus model is presented to demonstrate that variation in marker retention can lead to distortions in the estimates of distance. Multilocus simulations show that, when marker retention is constant across the chromosome, good estimates of physical distance can be derived using simple models of retention. However, further simulations exploring variable retention schemes demonstrate that significant errors in the estimates of map distances can occur. Ways of minimizing these distortions are discussed.

Chromosome Mapping↗

You can tell by the nose--judging sex from an isolated facial feature.

Measurements taken from the nose are among the most important physical variables which discriminate statistically between male and female faces, yet several investigators have claimed that it is difficult to judge sex on the basis of noses presented in isolation. Previous work on the isolated nose has, however, involved the use of frontal views only, which may have obscured important physical differences between the noses of males and females. An investigation of the accuracy of judgments of the sex of isolated noses observed in frontal, profile, and three-quarter views by male and female subjects is reported. Judgment of sex was performed significantly more accurately than chance in all cases except for frontal views of female noses, where judgment was significantly less accurate than chance. Analysis of variance demonstrated a significant interaction of sex of nose and view of nose, such that male noses were identified better in frontal and in profile views, but female noses better in the three-quarter view. It is suggested that one possible reason for the seemingly contradictory role of the nose in previous studies of sex judgment is that all noses look more male in frontal views. For a nose to be perceived as female, its distinctive shape must be made available to the perceiver; this is most likely from the three-quarter view.

Adolescent↗

Constructing plant radiation hybrid panels.

Radiation hybrid (RH) mapping, a somatic cell genetic technique, has been developed in animal systems as a general approach for the construction of long-range physical maps of chromosomes. This statistical method relies on X-ray induced breakage of chromosomes to determine the physical distance between markers, as well as their order on the chromosome. The method can be applied to single chromosomes or across the whole genome. The generation of plant (barley) radiation hybrids and their culture in vitro is described here. PCR-based marker systems are used to verify hybrid status and to demonstrate genome coverage. RH panels of the type generated can be used for physical mapping, map-based cloning, or sequence contig assembly. RH resources will greatly aid the physical characterisation of crop plants with large genomes.

Cells, Cultured↗

[Maternal posture and its influence on birthweight].

OBJECTIVE: To analyze the relationship between maternal posture/physical activity and inadequate birthweight. METHODS: Prospective cohort study involving 152 pregnant women from a public low-risk antenatal care facility. Three interviews evaluating the frequency of physical activity were administered to each pregnant woman during gestation. Birthweight (inadequate when <3,000 g and adequate when > or =3,000 g) was the dependent variable and the frequency of physical activity the independent variable. Statistical analysis was performed using logistic univariate analysis and multiple regression controlling for schooling, smoking, living with spouse, and baseline nutritional status. RESULTS: The practice of walking for at least 50 minutes during the first period of pregnancy was identified as a protective factor against inadequate birthweight (adjusted OR=0.44; 95% CI: 0.20-0.98). Standing for 2.5 hours or longer during the second semester of pregnancy was associated with increased risk (adjusted OR=3.23; 95% CI: 1.30-7.99). Dose-response relationships were identified for washing clothing by hand and cooking (p-value for linear trend <0.01 and 0.05, respectively). After confounder control, only washing clothing during the second trimester of gestation remained statistically significant. CONCLUSIONS: Our results show the importance of medical orientation regarding posture and physical activity during antenatal care, aiming at the reduction of inadequate birthweight.

Adolescent↗

One-year prospective quality-of-life outcomes in patients treated with angioplasty for symptomatic peripheral arterial disease.

BACKGROUND: Despite lower reported patency rates than open bypass, percutaneous transluminal angioplasty (PTA) may result in symptom relief, limb salvage, maintenance of ambulation and independent living, and overall improved quality of life. The goal of this study was to prospectively assess quality of life and functional outcomes after angioplasty and stenting in patients with chronic leg ischemia. METHODS: From August to December 2002, 84 patients with 118 chronically ischemic limbs underwent PTA with or without stenting as part of an ongoing prospective project performed to examine management of symptomatic peripheral arterial disease. All patients completed a preprocedure health questionnaire (Short Form 36) to provide adequate baseline data. Each patient was followed up every 3 months after treatment for 1 year to determine traditional outcomes of arterial patency, limb salvage, survival and amputation-free survival, and functional outcomes assessed according to improvement in quality of life, maintenance of ambulatory status, and maintenance of independent living status. The entire cohort was analyzed, as were subgroups of patients with lifestyle-limiting claudication and those with critical limb ischemia. Outcomes were analyzed by using Kaplan-Meier life-table analysis, the log-rank test for survival curves, and the one-sample t test. A Cox proportional hazard model was used to determine whether presentation and level of disease were independent predictors of outcome. RESULTS: Of the 84 patients, 54 (64.3%) were treated for claudication (34 aortoiliac occlusive disease and 20 infrainguinal disease), and 30 (35.7%) were treated for critical limb ischemia (11 aortoiliac occlusive disease and 19 infrainguinal disease). One-year results for the 54 patients with claudication were as follows: primary patency, 78.5%; limb salvage, 100%; amputation-free survival, 96.3%; survival, 96.3%; maintenance of ambulation status, 100%; and maintenance of independence, 100%. There was statistical improvement in all physical function categories, including physical function (29.4 +/- 8.9 vs 37.1 +/- 11.3; P < .0001), role-physical (32.5 +/- 11.3 vs 39.5 +/- 13.0; P = .0001), bodily pain (35.8 +/- 8.5 vs 42.9 +/- 10.9; P < .0001), and aggregate physical scoring (31.1 +/- 9.7 vs 38.1 +/- 11.5; P < .0001). One-year results for the 30 patients with critical limb ischemia were as follows: primary patency, 35.2%; limb salvage, 77.2%; amputation-free survival, 50.0%; survival, 60.0%; maintenance of ambulation status, 75.8%; and maintenance of independence, 92.8%. There was statistical improvement in bodily pain resolution (35.3 +/- 12.0 vs 46.6 +/- 12.0; P = .0009). Cox models with hazard ratios (HRs) revealed that presentation was a significant predictor for outcomes of primary patency (HR, 4.2; P= .0002), secondary patency (HR, 6.0; P < .0001), limb salvage (HR, 20.2; P = .0047), survival (HR, 10.9; P = .0002), and amputation-free survival (HR, 11.2; P < .0001). Conversely, the level of disease was predictive of outcome only for primary patency (HR, 1.8; P = .00289). CONCLUSIONS: Despite inferior reconstruction patency rates when compared with the historical results of open bypass, PTA provides excellent functional outcomes with good patient satisfaction, especially for treating claudication. These findings support a more liberal use of PTA intervention for patients with vasculogenic claudication.

Algorithms↗

Religion, social support, fat intake and physical activity.

OBJECTIVE: Most research on diet and exercise has focused on these health behaviours as proximate causes of disease, rather than examine the context of how diet and exercise are developed and maintained. This study examined religion and social support in relationship to fat intake and physical activity. DESIGN, SETTING AND SUBJECTS: Data from surveys of 546 adults aged 17-91 years, residing in one upstate New York county, were analysed. RESULTS: Most relationships between the multiple facets of religion, fat intake and physical activity were not statistically significant. After controlling for demographics and social support, Conservative Protestant women and women specifying an "Other" religious affiliation reported higher fat intakes than did Catholic women. There were no relationships between religion and fat intake in men. In women, religious commitment was associated with greater moderate and vigorous physical activity, whereas in men, divine social support was associated with greater moderate physical activity. Social support did not substantially change the magnitude of the relationships between religion, diet and physical activity. CONCLUSION: Overall, there were few relationships between religion, fat intake and physical activity, suggesting that in contemporary US society religion may play a small role in the context of how diet and exercise are developed and maintained. The limited range of religiosity in the sample, however, may have underestimated the role of religion. Significant relationships between religion and physical activity in women suggest that further research is needed to more clearly delineate religion's relationship with health behaviours.

Adolescent↗