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PubMedDate not supplied

Postoperative pain management in frail older adults.

PURPOSE: To evaluate the Frail Elder Pain Management Program (FEPMP) implemented for patients who had hip fracture repairs at a community hospital in 1995. Based on standards of geriatric and pain management practice, the FEPMP included education sessions, preprinted analgesic orders, pain flow sheets, written resources, and clinical support. A Logic Model reflected the program's conceptualization. DESIGN: Preexperimental pretest and posttest design. SAMPLE: A random sample of 50 charts of patients aged 75 and older who had hip fracture repairs were audited from each of two periods: the preimplementation period (1994-95) and the postimplementation period (1997-98). METHODS: A chart audit tool was developed, tested, and used. Data were analyzed using descriptive, parametric and nonparametric statistics. FINDINGS: Surgeons' prescriptions and nurses' pain management practices improved significantly (p = .0001). Pain assessment modestly improved. Patient outcomes also improved. IMPLICATIONS FOR PRACTICE AND EDUCATION: A programmatic approach to pain management is effective for improving practice and outcomes for frail elders.

Aged↗

PubMed1986

Life change stress factors in hospitalized otolaryngologic patients.

In this present era of specialty medicine and surgery, the physician should not lose sight of the total patient as he practices within the narrow limits of his specialty. Since there is evidence that stress created by life change factors may be associated with the onset of illness, we investigated life change factors in 100 patients hospitalized on an otolaryngology-head and neck surgery service to determine whether their stress scores were significantly higher than those of a nonhospitalized population of similar age and sociocultural background. The Social Readjustment Rating Scale (SRRS) was used to measure life change units (LCU) in the experimental and control groups. Nonparametric statistics used to analyze the data showed that at the .01 level of confidence hospitalized patients had stress scores significantly higher than those of the control group. We conclude that a clustering of life changes may have a significant impact on a patient's disease history. Awareness of LCU levels could be useful in detecting a patient's vulnerability to disease, and may therefore be useful in a preventive medicine approach to understanding and treating the total patient.

Adolescent↗

PubMed2001

The effective forces transmitted by high-speed, low-amplitude thoracic manipulation.

STUDY DESIGN: Twenty asymptomatic volunteers each received three spinal manipulative treatments to the thoracic spine. The treatments consisted of a straight posterior-to-anterior high-speed, low-amplitude thrust to the transverse process of T3-T10 using a reinforced hypothenar contact. All treatments were given by a full-time practicing clinician with 3 years of experience. OBJECTIVES: The primary objective of this study was to quantify local measures of loading applied by the clinician on the volunteers during spinal manipulative treatments and to compare these local measures of loading with previously described global measures. SUMMARY AND BACKGROUND DATA: The sparse information on the mechanics of spinal manipulative treatments deals exclusively with global force or pressure measurements. On the basis of these global data, incorrect conclusions may be drawn about the beneficial effects of spinal manipulative therapy, the loading of internal structures, and the risks associated with these treatments. METHODS: Twenty asymptomatic subjects each received three posterior-to-anterior, high-speed, low-amplitude spinal manipulative treatments to the transverse process of the thoracic spine. Total force, local force, contact area, peak pressure, and average pressure at the contact interface between clinician and subject were measured continuously by use of a thin, flexible pressure pad. Local and global measures of loading were compared and analyzed by use of nonparametric statistics (alpha = 0.01). RESULTS: The average peak total force was 238.2 N. The average peak local force over a target area of 25 mm2 was 5 N, indicating that global measures of loading vastly overestimate the local effective forces at the target site. The peak pressure point moved, on average, 9.8 mm during the course of the manipulation. CONCLUSIONS: To the authors' best knowledge, this is the first study to quantify local, effective measures of loading and compare them with the global measures typically used. The conclusions are limited because the study used a single clinician. The effective loading of specific target sites is much smaller than the global measures might suggest. This result occurs because as the forces during spinal manipulative treatment increase, so does the contact area; therefore, much of the total treatment force is taken up by non-target-specific tissues. Because of the vast discrepancy between the global and local measures of loading, it is suggested that risk-benefit assessments of high-speed, low-amplitude spinal manipulative treatments should be made, including local measures of loading. Finally, because theoretical approaches and the inverse dynamics approach can provide only global measures of loading, the results of such studies should be interpreted with caution.

Adult↗

PubMed2003

Bone mineral density changes within six months of renal transplantation.

BACKGROUND: The effective use of new steroid-sparing immunosuppressive regimens may lower cumulative glucocorticoid use among renal transplant recipients. However, it is unknown what effect this therapeutic trend has had on bone disease. METHODS: Unselected newly transplanted inpatients (n=45) were identified and comprehensively evaluated for metabolic bone disease at a median of 16 days (range 9-33) posttransplant. A follow-up evaluation was conducted a median of 5.7 months (range 4.8-9.3) later. Follow-up values for bone mineral density (BMD) and select laboratories were compared with baseline values using nonparametric statistics. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to describe the associations of baseline characteristics, select laboratory values, and cumulative prednisone and cyclosporine use with spinal BMD loss and were calculated using logistic regression. RESULTS: A significant decrease in intact parathyroid hormone (P<0.001) and a significant increase in calcitriol (P=0.02) were noted postengraftment. At follow-up, subjects had lost a mean of 2.4% BMD at the lumbar spine (P=0.003) but did not experience significant declines at the femoral neck. The highest tertiles of cumulative prednisone (OR=28.4; 95% CI 2.5-329 and OR=15.8; 95% CI 1.4-179, respectively) and past alcohol use (OR=9.3; 95% CI 1.46-58.5) were significantly associated with spinal BMD loss. CONCLUSIONS: Significant loss in lumbar BMD occurred within 6 months of transplantation in more than one third of a prospective cohort of renal transplant recipients. Lumbar bone loss seemed to be mediated primarily by glucocorticoid dose and a history of alcohol use.

Adult↗

PubMed2001

Fetal exposure to magnesium chloride-adenosine triphosphate (MgCl2-ATP) results in alterations in cerebral blood flow and a metabolic acidosis.

OBJECTIVE: Magnesium chloride-adenosine triphosphate (MgCl(2)-ATP), advocated as an adjunct treatment in shock resuscitation, might be useful for pregnant women who develop hypovolemia secondary to conditions such as placental abruption. The effects of this treatment on the fetus, however, have never been investigated. This study determined the direct, acute effects of MgCl(2)-ATP on fetal organ blood flow, hemodynamic measurements, and metabolic parameters before and after maternal hemorrhage. DESIGN: Experimental, randomized, nonblinded, control study. SETTING: Animal laboratory at a university research facility. SUBJECTS: This study was performed on 11 chronically instrumented, 123-day gestational age, pregnant ewes (term = 147 days) and their fetuses. INTERVENTIONS: Ewes were randomly allocated to either experimental (Expt, n = 5) or control (Cntl, n = 6) groups. After a 60-min baseline period, Expt fetuses received a 60-min iv infusion of MgCl(2)-ATP (150 &mgr;mole/hr each of MgCl(2) and ATP; at 3 mL/hr), and Cntl fetuses received an equivalent volume of 0.9% NaCl. After this infusion-only period, the infusion was continued, and ewes were intermittently bled over 1 hr for a total blood loss of 20 mL/kg (hemorrhage-plus-infusion period). After this, the infusions were continued, and ewes and fetuses were monitored for 1 additional hr (posthemorrhage period). Measurements: At the end of all periods, fetal and maternal blood pressures, blood gases, oxygen saturation, hemoglobin, serum electrolytes, and serum glucose concentrations were measured. At the end of the baseline, infusion-only, and hemorrhage-plus-infusion periods, fetal organ blood flows were determined using a fluorescent microsphere technique. Nonparametric statistics were used for comparisons (2-tailed, p </=.05). MAIN RESULTS: Maternal hemorrhage caused maternal hypotension, resulting in a decrease in fetal oxygen content and an increase in fetal hemoglobin and glucose concentrations. The changes were similar in both groups. In both groups, a progressive fetal metabolic acidosis developed during the hemorrhage period and it continued through the posthemorrhage period. This metabolic acidosis was more severe in the Expt fetuses and appeared to have started during the infusion-only period. There were no fetal deaths in either group. In the Cntl fetuses, there were increases from baseline after the hemorrhage-plus-infusion period in fetal adrenal (71%), brain (89%), and thymus (18%) blood flow and a decrease in muscle (-28%) blood flow. In the Expt fetuses, there were increases during the infusion-only period in adrenal (332%), myocardial (142%), and pancreatic (219%) blood flow and decreases in kidney (-25%) and skin (-75%) blood flow. These changes persisted during the hemorrhage-plus-infusion period. Most strikingly, regional cerebral blood flow in the Expt fetuses did not increase from baseline in any of the 10 brain areas sampled during the infusion-only period or following maternal hemorrhage. In Cntl fetuses, however, there was increase in blood flow in all 10 brain areas sampled following maternal hemorrhage. CONCLUSIONS: In healthy fetuses, direct MgCl(2)-ATP exposure caused metabolic acidosis and a redistribution of cardiac output to different organs. When the MgCl(2)-ATP fetuses were then subject to the effects of maternal hemorrhage, the expected increase in cerebral blood flow was not observed. Although an earlier study suggests that ATP may be beneficial to stressed fetuses when administered to mothers in labor, the direct effect of MgCl(2)-ATP appears to be potentially harmful by producing an acidosis and altering the normal fetal cerebral blood flow response to maternal hemorrhage.

Journal Article↗

PubMed2006

Patellofemoral pain syndrome: evaluation of location and intensity of pain.

OBJECTIVES: To identify the sites and intensity of pain in patients with patellofemoral pain syndrome. METHOD: A prospective cohort study was conducted at an academic sports medicine practice in Boston, Massachusetts. All patients met inclusion criteria and were enrolled and evaluated during the study time frame. A single sports medicine orthopaedic surgeon examined a consecutive sample of patients with patellofemoral pain not explained by one of several well-defined anterior knee pain diagnoses. The study group consisted of 100 patients (75 females, 25 males) with median age of 14 years. Eleven discrete locations were palpated for tenderness. Hamstring tightness was evaluated by measuring the popliteal angle. Patients reported intensity of pain using a 0- to 9-point ordinal scale. Regression and nonparametric statistical methods were used. RESULTS: The most common site of pain was the patella during anterior-posterior compression (90 patients), followed by the distal pole of the patella, the medial plica, and the nonarticular medial femoral condyle. Median "worst pain" intensity was 6 out of a possible 9. The most common site of "worst pain" was also the patella in compression (63 patients). Median duration of symptoms was 10 months, with an interquartile range of 3 to 20 months. Pain intensity was inversely correlated with duration of symptoms (P < 0.01). CONCLUSIONS: In these patients with patellofemoral pain syndrome, the major source of pain was the patella subchondral bone.

Adolescent↗

PubMedDate not supplied

Impact on the family: psychosocial adjustment of siblings of children who survive serious burns.

This study examined the psychosocial adjustment of 79 siblings of children suffering from burn injuries. Nonparametric statistics were used to compare psychosocial adjustment of the study group, as measured by the Child Behavior Checklist with an age-matched and gender-matched reference groups. Analyses found that the study group was better adjusted than the normative group on psychological dimensions; however, the study group fared worse than the normative group on overall competence, particularly social competence. Further analyses found significant differences in sibling adjustment as a function of the severity of the burn injury. The siblings of children with moderate burn injuries did significantly better on psychological adjustment than the normative group, and siblings of children with moderate and severe burn injuries did significantly poorer on social competence. Descriptive analysis of measures developed for the study for parent and sibling reports supported findings of the Child Behavior Checklist quantitative analysis and offered insight into reasons for findings. Results indicate that the burn injury to one child in a family significantly impacts the siblings of that child. The noninjured child may be strengthened in the process of adapting to the changes imposed on the family, but it is also possible that the sibling's growth in one dimension is at the cost of success in another dimension.

Adaptation, Psychological↗

PubMed2005

Magnetic resonance imaging study of the level of termination of the conus medullaris and the thecal sac: influence of age and gender.

STUDY DESIGN: Sequential study of magnetic resonance imaging (MRI) of the spine for assessing the level of termination of the conus medullaris (CMT) and thecal sac (TST). OBJECTIVES: To determine the variation in CMT and the TST as a function of age and gender in an adult population without spinal deformity and to investigate the relationship between CMT and TST. SUMMARY OF BACKGROUND DATA: It is generally accepted that the conus medullaris terminates in the lower third of L1; however, a wide range of values has been reported in cadaver studies as well as in MRI studies during life. There have been only a few reports on the influence of gender on the CMT, and the influence of age has not been studied at all. There have been few studies on the range of termination of the thecal sac, and the influence of age and gender remain unexplored. METHODS: We reviewed the 3-mm sagittal MR images of 635 patients, including 297 women and 338 men, with a mean age of 49.43 years. The CMT and TST were located in relation to spinal levels and assigned numerical values ranging from 0 to 13. Parametric and nonparametric statistical tests were used for the data analysis. RESULTS: Mean CMT was at the level of the middle third of L1. The range span extended from the lower third of Th11 to the upper third of L3. The CMT displayed a small but significant positive correlation with age and with gender. Mean TST was at the level of the upper third of S2. The range extended from the lower third of L3 to the upper third of S5. The TST was not affected by gender, but age had an effect on TST. CONCLUSIONS: The CMT and TST displayed a wide range of values in our study. We detected small but systematic influences of gender and age on CMT and of age on TST, as well as a positive correlation between CMT and TST. These effects are small in amplitude, but they met all the criteria for statistical significance and have practical value for clinicians, as well as theoretical value for the medical and biologic community.

Adolescent↗

PubMed2006

Interobserver and intraobserver reliability of maximum canal compromise and spinal cord compression for evaluation of acute traumatic cervical spinal cord injury.

STUDY DESIGN: Prospective, blinded validation study of an objective, quantitative measure to assess maximum canal compromise (MCC) and maximum spinal cord compression (MSCC) in individuals with acute cervical spinal cord injury (SCI). OBJECTIVE: To examine the intraobserver and interobserver reliability of MCC and MSCC in individuals with acute traumatic cervical SCI. SUMMARY OF BACKGROUND DATA: To date, few quantitative reliable radiologic methods for assessing the extent of spinal cord compression in the setting of acute SCI have been reported. MCC and MSCC, as assessed on mid-sagittal CT and T2-weighted MR images, respectively, appear to have potential clinical and prognostic value. To date, the validation of these assessment tools has been limited to a small number of observers at a single institution. However, to date no study has focused on the reliability of these radiologic parameters among a large cohort of spine surgeons from North America and abroad. This type of validation is critical to allow the broader use of these outcome measures in research studies and in clinical practice. METHODS: Mid-sagittal MRI and CT images of cervical spine were selected from 10 individuals with acute traumatic cervical SCI. A total of 28 spine surgeons independently estimated CT MCC, T1-weighted MRI MCC, and T2-weighted MRI MSCC on two occasions using a calibrated ruler. In the first round of measurements, the observers estimated the radiologic parameters using only written instructions. The second measurement set was obtained after an interactive teaching session on the methodology. The order of the images was altered for the second set of measurements. RESULTS: Analysis using parametric and nonparametric statistics indicated high intraobserver reliability for CT MCC, T1-weighted MRI MCC, and T2-weighted MSCC with interclass correlation coefficients (ICCs) of 0.92, 0.95, and 0.97, respectively. The interobserver reliability for all three radiologic parameters was considered moderate with ICCs ranging from 0.35 to 0.56. CONCLUSION: Our results indicate that the intraobserver reliability for the MCC and MSCC was high. Although the interobserver reliability for all three radiologic parameters in the present study was below 0.75, the observed differences were small and largely accounted for by the limitations in the precision of the calibrated ruler. For cases with minimal cord compression, the measurement of canal stenosis (MCC) proved more accurate. In contrast, in cases with severe cord compression, the assessment of MSCC was more accurate. It is anticipated that the use of digital imaging technologies will further enhance the precision of these outcome measures.

Acute Disease↗

PubMed2006

Recovery of pulmonary function following endoscopic anterior scoliosis correction: evaluation at 3, 6, 12, and 24 months after surgery.

STUDY DESIGN: A series of patients with scoliosis undergoing endoscopic anterior instrumentation and fusion undertaking repeated pulmonary function assessments. OBJECTIVE: To assess recovery of pulmonary function in the 2 years following endoscopic anterior scoliosis correction. SUMMARY OF BACKGROUND DATA: Recent studies have found that pulmonary function returns to preoperative levels 12-24 months following endoscopic anterior scoliosis correction, and a small improvement in forced expiratory volume (FEV1) has also been reported. METHODS: A series of 44 patients with endoscopic anterior scoliosis correction had pulmonary function tests before surgery, and at 3, 6, 12, and 24 months after surgery. Forced vital capacity (FVC), FEV1, and total lung capacity (TLC) were measured. Nonparametric statistical analysis was used to investigate changes in pulmonary function between successive assessments. RESULTS: Pulmonary function decreased by approximately 10% at 3 months after surgery. At 24 months after surgery, FVC and FEV1 recovered to 5% to 8% higher than preoperative levels, while TLC returned to preoperative levels. Statistically significant improvements in most pulmonary function values occurred between 3 and 6, and 6-12 months. Improvements in mean FVC, FEV1, and TLC continue between 12 and 24 months, although only the increase in absolute FVC for this time is statistically significant. CONCLUSIONS: Endoscopic anterior scoliosis surgery has no lasting negative effect on pulmonary function, and with prolonged follow-up, pulmonary capacity improves beyond preoperative levels.

Adolescent↗

PubMed2005

Metabolic ratios of psychotropics as indication of cytochrome P450 2D6/2C19 genotype.

The cytochrome P450 enzymes (CYP) 2C19 and 2D6 are involved in the metabolism of many psychotropic drugs. Variability in enzyme activity results in variable metabolic capacities, affecting the metabolism of substrates. The metabolic ratio (MR) of drugs metabolized via these enzymes may therefore reflect the enzyme's activity and/or genotype. To serve as an example for different groups of medications, the selective serotonin reuptake inhibitor venlafaxine, the tricyclic antidepressant amitriptyline, and the antipsychotic risperidone were studied to examine a possible correlation between the MRs of these drugs and the CYP2C19 and/or CYP2D6 genotype. For this purpose data from routine genotyping and serum level analysis were used. The relationships between the observed metabolic ratios and CYP2D6 and/or CYP2C19 genotype were characterized using nonparametric statistical analysis. A clear correlation was observed between the CYP2D6 genotype and the metabolic ratio of venlafaxine. Genotyping of individuals with a log(MR) < -0.6 or a log(MR) > 0.2 would include all patients with an aberrant genotype but would result in a reduction of 52% of genotyping reactions. Slow metabolism of amitriptyline is correlated with a log(MR) > 0.4. Genotyping only those subjects with a log(MR) > 0.4 would result in 88% fewer genotyping reactions. For risperidone, genotyping individuals with a log(MR) > 0.4 would include all CYP2D6 poor metabolizers while reducing the number of genotyping reactions by 93%. According to these data, correlations exist between the log(MR) of venlafaxine, amitriptyline, and risperidone and the genotype of the CYP enzymes involved in their metabolism. From the ranges of log(MR) defined here, a high percentage of aberrant metabolizers can be detected even when patients are not routinely genotyped. Thus, the metabolic ratio may serve as an indication of when genotyping should be considered.

Alleles↗

PubMedDate not supplied

Early postmenopausal hormone therapy improves postural balance.

OBJECTIVE: Postmenopausal hormone therapy (HT) results in more substantial reductions in the risk of hip fracture when initiated sooner rather than later after menopause. We studied the effects of postmenopausal HT on the postural balance of postmenopausal women, with further assessment according to the time since they achieved menopause. DESIGN: One hundred women with a mean age of 52.5 years (91 evaluable) were randomly and blindly assigned to either a sequential estradiol-norethisterone acetate regimen or placebo for 3 months, after which all participants received open HT for a further 3 months. Postural balance was assessed as sway velocity using a force platform. RESULTS: After 3 months of HT, sway velocity had improved (decreased) from baseline by 7.0% (P = 0.007 vs baseline and P = 0.038 vs placebo). Continued HT for 6 months further improved sway velocity by 12% from baseline (P < 0.0001) to reach values similar to those historically found in younger women or in postmenopausal women after long-term HT. Closer proximity to menopause and more pronounced increases in serum estradiol values were associated with stronger improvements in sway velocity (P = 0.018 for interaction). HT also improved dizziness (P = 0.016 vs baseline and 0.022 vs placebo). (Nonparametric statistics are used throughout, except for analyses of interaction and dizziness.) CONCLUSIONS: Initiation of HT soon after menopause rapidly improved postural balance to levels normally seen in young women. We suggest that improved postural balance can contribute to the protection against fractures associated with HT and explain the more substantial reduction in hip fracture risk after HT initiated sooner, compared with later, after menopause. Further study is required to confirm these results.

Dizziness↗

PubMed2005

The comparison of overnight lens modalities (COLM) study.

PURPOSE: The Comparison of Overnight Lens Modalities (COLM) Study is a controlled, randomized, clinical pilot study to determine the sample size required to perform a multicenter clinical trial comparing Paragon CRT lenses with CIBA Vision Focus NIGHT and DAY 30-day continuous-wear silicone hydrogel lenses. METHODS: Twenty subjects were enrolled in the study. Eighteen subjects, 8 CRT and 10 Focus NIGHT and DAY lens wearers, completed the 3-month study. Visual acuity and refractive quality of life were assessed. Nonparametric statistics were used to analyze differences within and between treatment groups for refraction, visual acuity, and refractive quality of life. The Wilcoxon rank sum test was used to analyze differences between the groups in refraction, visual acuity, and refractive quality of life. The Wilcoxon signed rank test was also used to monitor changes in refraction, refractive quality of life, and visual acuity within a group. Sample size calculations were performed to determine the sample size needed for a large-scale clinical trial. RESULTS: No statistically significant difference was observed between the groups for 12 of 13 scales on the National Eye Institute Refractive Error Quality of Life Instrument (NEI RQL-42) after treatment. A statistically significant difference was observed between the CRT and Focus NIGHT and DAY groups after 3 months for the NEI RQL-42 dependence-on-correction scale (P=0.0032). There was a significant change within the CRT group between baseline and 3 months (P=0.0156). No statistically significant difference was observed between the two groups in Bailey-Lovie high- and low-contrast visual acuity after 3 months. CONCLUSIONS: The NEI RQL-42 may be able to detect differences in refractive quality of life between two contact lens treatment groups for the dependence-on-correction scale. Paragon CRT and CIBA Vision Focus NIGHT and DAY lenses produced similar high- and low-contrast visual acuity in this study. A sample size of 126 subjects per group is required to find a 10-unit difference on the NEI RQL-42.

Adult↗

PubMed2003

Variation in urine composition in the human urinary tract: evidence of urothelial function in situ?

PURPOSE: An increased awareness of the concept that the urothelium has a significant transport function led us to question whether urine composition changes as it passes along the human lower urinary tract. MATERIALS AND METHODS: Urine samples from the bladder and renal pelvis were collected from 30 adults who underwent percutaneous nephrolithotomy (27) or ureteral stent insertion before lithotripsy (3). Urine was obtained from the 2 renal pelves (operative and contralateral sides) in 6 patients (24%). Urine pH was measured using an ultra-thin glass pH electrode. Urinary osmolality, Na and K were measured by micro-osmometry and flame photometry, respectively. Comparison of data sets was achieved using conventional nonparametric statistical methods. RESULTS: Median bladder urine pH in 30 patients, osmolality in 16, Na in 16 and K in 15 were significantly higher than in the renal pelvis at 6.76 (IQR 6.23 to 6.99), 469 mOsm. kg.1 (IQR 349 to 553), 132 (IQR 100 to 154) and 45 mM. (IQR 30 to 64) versus 6.08 (IQR 5.84 to 6.89), 308 mOsm. kg.1 (IQR 248 to 465), 90 (IQR 69 to 115) and 17 mM. (IQR 10 to 47), respectively (p < or = 0.05). There was no significant difference in these parameters in the urine of the paired renal pelves. CONCLUSIONS: Bladder urine pH, osmolality, Na and K significantly differ from values in the renal pelvis in moderately hydrated humans. Our data show that urine composition is modified in the lower urinary tract, supporting the concept of a dynamic urothelium. We propose that urothelial-urinary interactions and urinalysis need reappraisal, particularly in investigations of urinary stone formation and sensory bladder function.

Adult↗

PubMed2006

Improving antibiotic selection: a systematic review and quantitative analysis of quality improvement strategies.

OBJECTIVE: We sought to assess which interventions are most effective at improving the prescribing of recommended antibiotics for acute outpatient infections. DESIGN AND METHODS: We undertook a systematic review with quantitative analysis of the Cochrane Registry Effective Practice and Organization of Care (EPOC) database, supplemented by MEDLINE and hand-searches. Inclusion criteria included clinical trials with contemporaneous or strict historical controls that reported data on antibiotic selection in acute outpatient infections. The effect size of studies with different intervention types were compared using nonparametric statistics. To maximize comparability between studies, quantitative analysis was restricted to studies that reported absolute changes in the amount of or percent compliance with recommended antibiotic prescribing. RESULTS: Twenty-six studies reporting 33 trials met inclusion criteria. Most interventions used clinician education alone or in combination with audit and feedback. Among the 22 comparisons amenable to quantitative analysis, recommended antibiotic prescribing improved by a median of 10.6% (interquartile range [IQR] 3.4-18.2%). Trials evaluating clinician education alone reported larger effects than interventions combining clinician education with audit and feedback (median effect size 13.9% [IQR 8.6-21.6%] vs. 3.4% [IQR 1.8-9.7%], P = 0.03). This result was confounded by trial sample size, as trials having a smaller number of participating clinicians reported larger effects and were more likely to use clinician education alone. Active forms of education, sustained interventions, and other features traditionally associated with successful quality improvement interventions were not associated with effect size and showed no evidence of confounding the association between clinician education-only strategies and outcome. CONCLUSIONS: Multidimensional interventions using audit and feedback to improve antibiotic selection were less effective than interventions using clinician education alone. Although confounding may partially account for this finding, our results suggest that enhancing the intensity of a focused intervention may be preferable to a less intense, multidimensional approach.

Anti-Bacterial Agents↗

PubMed2006

Long-term evaluation of eccentric viewing spectacles in patients with bilateral central scotomas.

PURPOSE: Yoked prism spectacles (eccentric viewing spectacles [EVS]) facilitate eccentric viewing in patients with bilateral central scotomas. This study was conducted to evaluate the long-term success and patient satisfaction of this type of low-vision aid. METHODS. In this retrospective cross-sectional study, we reviewed the low-vision rehabilitation records of all patients who received EVS since 1993. With an 18-item survey, 191 patients were questioned about the wearing characteristics, advantages, and disadvantages of the EVS. Descriptive and nonparametric statistics were applied to compare regular users with those persons who no longer use the EVS. RESULTS: The response rate was 83.2% and the average follow-up time was 4.5 years. Forty percent of all patients still used the EVS. The main disadvantages of these spectacles, mentioned mainly by the nonusers, included the heavy weight (41%), perception of curved lines (46%), dizziness during walking (46%), and poor cosmetic appearance (25%). Many successful long-term users considered the EVS suitable for home activities (86%) and walking in the street (70%) and reported that this device reduced eccentric viewing (77%), created better vision in the center of their visual field (67%), and helped with recognition of objects and faces (64%). CONCLUSIONS: The prescription of EVS aids eccentric viewing in patients with dense central scotomas. Although associated with a number of disadvantages and side effects, 40% of the patients continued to use EVS. The results of this study indicate that patients who experience difficulties with eccentric fixation are most likely to benefit from these low-vision aids. A thorough explanation of the advantages and disadvantages of the EVS is important to prevent unnecessary disappointments.

Adult↗

PubMed2007

T-lymphocyte profile and total and virus-specific immunoglobulin concentrations in the cervix of HIV-1-infected women.

BACKGROUND: The mucosal lymphocyte population is the largest in the body, and the gastrointestinal compartment has been well characterized in HIV infection. Much less is known about the effects of HIV on the genital tract. OBJECTIVE: : To examine the T-lymphocyte phenotype and receptor repertoire as well as total and virus-specific immunoglobulin concentrations in the endocervix of HIV-infected women at different stages of infection as compared with uninfected women. PATIENTS AND METHODS: Participants were 12 seronegative women, 10 HIV-infected "slow progressors" not taking antiretroviral therapy, and 9 HIV-infected women whose antiretroviral therapy was failing. We used multiparameter flow cytometry to enumerate T-cell populations on cytobrush-obtained cervical specimens, the immunoscope technique to determine the T-cell receptor (TCR) repertoire, and quantitative enzyme-linked immunosorbent assays for antibody determinations on cervical secretions absorbed onto ophthalmic sponges. Nonparametric statistical analyses were performed. RESULTS: We found marked depletion of leukocytes and CD4 T lymphocytes in the endocervix of HIV-infected women as compared with uninfected women; this was significant at more advanced disease stages. Naive T cells were rare in the endocervix of all groups. Activation marker expression was higher in endocervical T lymphocytes than in peripheral blood among control and slow-progressing HIV-infected women but not in women failing therapy. Endocervical T lymphocytes showed highly restricted utilization of Vbeta TCR families. Unlike other mucosal sites, the cervix contained IgG as the predominant immunoglobulin isotype. HIV-IgG was detected in the cervix of most HIV-infected women and in blood of all infected women. CONCLUSIONS: HIV infection induces substantial changes in the immune profile of the female genital tract. Further study of the implications of these findings for HIV acquisition and transmission is needed.

Adult↗

PubMed1998

Patterns of density dependence in measles dynamics.

An important question in metapopulation dynamics is the influence of external perturbations on the population's long-term dynamic behaviour. In this paper we address the question of how spatiotemporal variations in demographic parameters affect the dynamics of measles populations in England and Wales. Specifically, we use nonparametric statistical methods to analyse how birth rate and population size modulate the negative density dependence between successive epidemics as well as their periodicity. For the observed spatiotemporal data from 60 cities, and for simulated model data, the demographic variables act as bifurcation parameters on the joint density of the trade-off between successive epidemics. For increasing population size, a transition occurs from an irregular unpredictable pattern in small communities towards a regular, predictable endemic pattern in large places. Variations in the birth rate parameter lead to a bifurcation from annual towards biennial cyclicity in both observed data and model data.

Disease Outbreaks↗