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Biomedical subjects

M Cohen

Publications and source records attributed to M Cohen.

At least 325 records · Page 18Linked to original sources
PubMed1997

Vertebral body MRI related to lumbar fusion results.

The evaluation of continued pain after a technically successful posterolateral lumbar spine fusion is often challenging. Although the intervertebral disc is often a source of low back pain, abnormal endplates may also be a focus of pain, and possibly a source of continued pain after a posterolateral fusion. MRI allows noninvasive evaluation for disc degeneration, as well as for abnormal endplates and adjacent vertebral body marrow. Previous studies have found inflammatory marrow changes, adjacent to abnormal endplates, associated with disc degeneration in low back pain patients. In this study, preoperative MRI scans in 89 posterolateral lumbar fusion patients were reviewed, by an independent radiologist, to determine whether vertebral body marrow changes adjacent to the endplates were related to continued pain. Independent chart review and follow-up telephone interview of all patients at a 4-year follow-up (mean) formed the basis for the clinical results. Vertebral body MRI signals consistent with inflammatory or fatty changes were found in 38% of patients, and always occurred adjacent to a degenerated disc. Inflammatory MRI vertebral body changes were significantly related to continued low back pain at P = 0.03. We conclude that posterolateral lumber fusion has a less predictable result for the subset of degenerative disc patients with abnormal endplates and associated marrow inflammation. More research is needed to determine the biological and biomechanical effects of posterolateral fusion upon the endplate within the fused segments. If indeed further study supports the hypothesis that abnormal endplates associated with inflammation are a source of pain, then treating the endplates directly by anterior fusion may be a preferred treatment for this subset of degenerative patients.

Adolescent↗
PubMed1997

Living with mastectomy and breast conservation treatment: who suffers more?

Sixty-five patients who underwent modified radical mastectomy were compared with 55 breast conservation patients, all of whom were in stage I, II or III of breast cancer and were under treatment at an oncology clinic in northern Israel. The main findings indicate no differences between the groups in physical, psychosocial, marital or medical interaction, according to the CARE scale. These findings reflect the results of similar comparative studies conducted during the 1980s and 1990s as documented in the literature. Sexual interaction showed statistical differences favoring the women who had undergone mastectomies.

Adult↗
PubMed1997

Natural history of HIV infection in women.

Women represent the fastest growing group of adults with AIDS, and poor African-American and Latina women are disproportionately affected. There are differences in the clinical presentation of HIV symptoms in women. Although disease progression seems to be similar for women and men, women with HIV infection seem to have a higher mortality rate than men. Gender, racial, and class differences in access to care may account for this. Phases of the natural history of HIV infection in women are reviewed and include prevention opportunities, acute infection, viral and immunologic parameters of pathogenesis, therapeutic plans, and terminal care.

AIDS-Related Opportunistic Infections↗
PubMed1997

Blood pressure and metabolic responses to moderate sodium restriction in isradipine-treated hypertensive patients.

This multicenter, randomized, controlled clinical trial assessed the influence of sodium chloride intake on the antihypertensive effect of the calcium channel blocker isradipine. Participants with uncomplicated hypertension controlled by isradipine entered a 4-week sodium-restricted (60 to 80 mmol/24 h) period. Participants with urinary sodium levels < 120 mmol/24 h (n = 99) were randomized to placebo or sodium chloride (100 mmol/24 h) for 4 weeks, and then crossed over to the alternative treatment for an additional 4 weeks. Mean baseline systolic blood pressure was 151.9 +/- 16.7 mm Hg (mean +/- SD). During open-label isradipine treatment, systolic blood pressures for ad libitum sodium chloride and restriction were 134.1 +/- 11.1 and 132.1 +/- 12.2 mm Hg respectively; for double-blind sodium chloride restriction and supplementation: 133.6 +/- 12.6 and 138.5 +/- 12.8 mm Hg (P < .01). Urinary sodium excretion values for open-label isradipine ad libitum versus restricted were 140.6 +/- 61.9 versus 76.9 +/- 32.4 mmol/24 h; for double-blind restricted versus supplemented, sodium excretion was 120.5 +/- 68.9 v 175.9 +/- 68.7 mmol/24 h (P < or = .0001). Changes in urinary sodium excretion were not predictive of variations in blood pressure. Urinary sodium excretion during sodium restriction correlated directly with HDL-cholesterol (P < .02) and inversely with total cholesterol:HDL-cholesterol (P = .02), despite decreased total and saturated fat intake (P < .01). Sodium restriction was associated with significant reductions (P < .01) in virtually all macronutrients and electrolytes, and thus had an adverse impact on overall nutrition. The antihypertensive action of isradipine was not enhanced by dietary sodium chloride restriction, and the lipoprotein profile was least favorable with sodium chloride restriction.

Adult↗
PubMed1997

The Essence Trial: Efficacy and Safety of Subcutaneous Enoxaparin in Unstable Angina and Non-Q-Wave MI: A Double-Blind, Randomized, Parallel-Group, Multicenter Study Comparing Enoxaparin and Intravenous Unfractionated Heparin: Methods and Design.

Antithrombotic therapy reduces the risk of recurrent ischemic events in patients with unstable angina. The primary aim of the ESSENCE trial is to evaluate the efficacy of enoxaparin (low molecular weight heparin) versus unfractionated heparin, plus aspirin, in patients with rest angina or non-Q-wave infarction. This is a randomized, double-blind, placebo-controlled study of 3180 patients comparing enoxaparin, 1 mg/kg sc bid, with unfractionated heparin via continuous iv infusion to maintain the aPTT at 2 x control. Patients within 24 hours of the onset of acute myocardial ischemia without ST elevation are eligible, and trial therapy is administered for a minimum of 48 hours to a maximum of 8 days. Primary endpoints analyzed are death, myocardial infarction (MI), or recurrent angina at 14 days. Currently 3019 patients have been randomized in 10 countries. The mean age is 64 years, 33% are female, and 46% have had a prior MI. The overall event rates at 14 days are 1.7% mortality, 5.9% subsequent MI, and 17% recurrent angina. The composite triple endpoint rate is 23.6%. Recruitment should be complete by June 1996. The methods and design of the study are presented in this article.

Journal Article↗
PubMed1997

Prospective Comparison of Patient Characteristics and Outcome of Non-prior Aspirin Users versus Aspirin Users with Unstable Angina or Non-Q-Wave Myocardial Infarction Treated with Combination Antithrombotic Therapy.

The objective of this study was to determine if aspirin users presenting with acute coronary syndromes are at higher risk for subsequent clinical events. In a trial evaluating combination antithrombotic therapy in resting angina or non-Q-wave myocardial infarction (MI), patients were prospectively dichotomized on admission into nonprior versus recent aspirin users. Then 105 nonprior users and 144 users were randomized to treatment with aspirin plus heparin/warfarin for 12 weeks. Recurrent myocardial ischemia occurring during the 12-week follow-up period was defined as recurrent angina (with electrocardiographic changes or prompting coronary revascularization), MI, or death. Prior aspirin users had a significantly higher incidence of previous MI, prior bypass grafting, beta-blocker use, or hypertension (p </= 0.003) and were more likely to present with unstable angina as opposed to non-Q-wave MI. (p </= 0.008). The cumulative probability of recurrent ischemic endpoints for nonprior versus recent users was 10% versus 21% at 14 days (log rank p = 0.03), and 19% versus 29%, at 12 weeks (p = 0.06). Using the Cox model, adjusting for variables significantly associated with outcome, aspirin use remained a significant predictor of 14-day outcome (p = 0.04) but not of 12-week outcome (p = 0.06). In conclusion, even after adjusting for significant differences in baseline variables, aspirin users presenting with rest angina or non-Q-infarction have a worse short-term prognosis in spite of maximal medical therapy.

Journal Article↗
PubMed1997

Prediction of vocational outcome based on clinical and demographic indicators among vocationally ready clients.

This study examined the clinical and demographic correlates of work skills and vocational outcome for persons with psychiatric disabilities. The same clinical, demographic, work skills, and vocational outcome instruments were administered to 275 persons working toward their vocational goals at three psychosocial rehabilitation centers. Data regarding vocational outcomes were collected quarterly over a period of 3 1/4 years. Using multivariate statistical techniques, clinical and demographic variables that predict work skills and future vocational outcomes were identified. The implications of the findings for program administrators, system planners, and researchers are discussed.

Adult↗
PubMed1997

Neural dynamics of variable-rate speech categorization.

What is the neural representation of a speech code as it evolves in time? A neural model simulates data concerning segregation and integration of phonetic percepts. Hearing two phonetically related stops in a VC-CV pair (V = vowel; C = consonant) requires 150 ms more closure time than hearing two phonetically different stops in a VC1-C2V pair. Closure time also varies with long-term stimulus rate. The model simulates rate-dependent category boundaries that emerge from feedback interactions between a working memory for short-term storage of phonetic items and a list categorization network for grouping sequences of items. The conscious speech code is a resonant wave. It emerges after bottom-up signals from the working memory select list chunks which read out top-down expectations that amplify and focus attention on consistent working memory items. In VC1-C2V pairs, resonance is reset by mismatch of C2 with the C1 expectation. In VC-CV pairs, resonance prolongs a repeated C.

Computer Simulation↗
PubMed1997

Squamous cell carcinoma in perineal inflammatory disease.

Four patients with squamous cell carcinoma of the perineal region were diagnosed and treated during the last 4 years in our institutions. The underlying diagnoses consisted of recurrent pilonidal disease, Crohn's disease, and hidradenitis suppurativa. In all patients, a pattern of a long-term inflammatory process was evident. Current concepts regarding the pathophysiology of a chronic inflammatory state and malignant transformation are reviewed. We conclude that regardless of the original pathology, all chronic inflammatory processes in the perineal region should be evaluated for malignant degeneration. A high index of suspicion may potentiate an early diagnosis, possibly improving the chance of cure.

Abscess↗
PubMed1997

Median sternotomy wound complication: the effect of reconstruction on lung function.

The objective of the study was to evaluate the lung function of patients with median sternotomy wound complication during the early postmedian sternotomy period and to compare the long-term pulmonary effects of reconstruction using pectoralis major and rectus abdominis muscle flaps. The percentage of predicted, standardized forced vital capacity (FVC); the standardized forced expiratory volume in 1 second (FEV1), and FEV1/FVC ratios of 45 patients with a median sternotomy wound complication were evaluated before and at a mean time of 10.6 months after wound reconstruction. Both mean FVC and FEV1 increased after wound revision compared with the prereconstruction results (8.4% and 9.2% increase, respectively). Patients with painful chest wall movement had the worst (60%) mean FVC and FEV1 before reconstruction when compared with a nonpainful complication. Reconstruction with a muscle flap was followed by an increase of 8.6% and 7.3% in FEV1 and FVC, respectively, from prereconstruction results. However, long-term results indicate that these patients have a mild, restrictive impairment of their lung function tests (LFTs), with about 80% of the predicted FVC and FEV1. Among the muscle flaps, the best improvement and best long-term LFT results were after sternectomy and reconstruction with a pectoralis major muscle flap as compared with a rectus abdominis muscle flap. Sternectomy and reconstruction with a muscle flap is a well-tolerated procedure associated with improvement of lung function compared with prereconstruction values. A pectoralis major muscle flap should be the first choice for muscle flap reconstruction while a rectus abdominis muscle flap should be reserved only for patients with good LFTs before reconstruction.

Adult↗
PubMed1997

Financial outcome of treating trauma in a rural environment.

The financial plight of the urban trauma center is well documented. However, the financial status of the rural trauma center is largely unknown. We hypothesized that our rural trauma center with a high number of blunt trauma patients, a wide spectrum of injury severity, and a large percentage of insured patients would prove to be financially advantageous to the institution. From January 1994 to June 1995, 1,119 consecutive trauma admissions had a complete financial profile compiled including actual costs, reimbursements, and reimbursement ratio (RR = reimbursement/actual costs). Our injury severity profile was very skewed with a preponderance of less severely injured patients (mean Injury Severity Score = 9.6 +/- 7.8). The payor profile of these patients included 49.2% fee-for-service (RR = 1.43), 25.4% diagnosis-related group-based (RR = 0.92), 8.77% per diem (RR = 0.51), and 1.25% capitated (RR = 0.47). Overall, the RR for the trauma unit was 1.11, representing a net profit overall. Cost closely tracked both hospital and intensive-care unit length of stay (R2 = 0.925). Likewise, reimbursement also was reflected in both hospital and intensive-care unit length of stay (R2 = 0.735). We conclude that our rural trauma center, with a favorable payor mix and low injury severity, is financially profitable.

Adult↗
PubMed1997

Trauma registry injury coding is superfluous: a comparison of outcome prediction based on trauma registry International Classification of Diseases-Ninth Revision (ICD-9) and hospital information system ICD-9 codes.

BACKGROUND: Trauma registries are an essential but expensive tool for monitoring trauma system performance. The time required to catalog patients' injuries is the source of much of this expense. Typically, 15 minutes of chart review per patient are required, which in a busy trauma center may represent 25% of a full-time employee. We hypothesized that International Classification of Disease-Ninth Revision (ICD-9) codes generated by the hospital information system (HI) would be similar to those coded by a dedicated trauma registrar (TR) and would be as accurate as TR ICD-9 codes in predicting outcome. METHODS: One thousand eight hundred twelve patients admitted to a Level I trauma center during 2 years had International Classification of Disease Injury Severity Scores (ICISS) calculated based on HI and TR ICD-9 codes. The relative predictive powers of these two ICISSs were then compared for every patient using Receiver Operator Characteristic Curve Area (ROC) and Hosmer Lemeshow Statistics. RESULTS: Eighty-nine percent of patients (1,608 of 1,812) had identical HI and TR ICISSs. Eleven patients' ICISSs differed by >0.1, and only two patients' scores differed by >0.2. ICISS proved to be a powerful predictor of outcome whether derived from HI (ROC = 0.884; 95% confidence interval (CI) = 0.850-0.917) or TR (ROC = 0.872; 95% CI = 0.837-0.908). Although these predictive powers were not significantly different (p = 0.076), the trend was for HI to perform better than TR. ISS calculated for the same data set using the MacKenzie dictionary proved significantly less predictive of outcome than either ICISS (ROC(MacKenzie) = 0.843; 95% CI = 0.792-0.884; p = 0.034). CONCLUSION: We conclude that in our hospital TR data on individual injuries can be replaced by HI data without loss of predictive power. ISS based on the MacKenzie dictionary should be abandoned because it is much less predictive of outcome than ICISS.

Adolescent↗
PubMed1997

Longitudinal analysis of mandibular asymmetry in hemifacial microsomia.

Reconstruction of the mandible is one of the key elements in the skeletal rehabilitation of patients with hemifacial microsomia. Unfortunately, knowledge about long-term mandibular skeletal growth in these patients is lacking. The purpose of this study was to analyze mandibular skeletal growth longitudinally in unoperated hemifacial microsomia patients from childhood to adolescence. The longitudinal records of 26 patients with unoperated unilateral hemifacial microsomia were utilized. The average age at initial records was 3.1 years, and the average age at final records was 16.7 years. Posteroanterior cephalometric radiographs were utilized to evaluate both horizontal and vertical mandibular asymmetry. Patients also were analyzed according to the grade and side of the mandibular deformity. A paired t-test (p < 0.05) and a two-way ANOVA were used to analyze the data. There were 5 patients with grade I, 14 with grade II, and 7 with grade III. The results indicated that the skeletal mandibular asymmetry in hemifacial microsomia is not progressive in nature and that growth of the affected side in these patients parallels that of the nonaffected side. The grade and the side of the mandibular deformity did not influence these findings. These results should be considered when treatment strategies are developed to reconstruct the asymmetrical mandible in hemifacial microsomia.

Anthropometry↗
PubMed1997

Mental health practices of Ontario family physicians: a study using qualitative methodology.

OBJECTIVE: To obtain descriptions of how family physicians detect and manage mental health problems commonly encountered in their practices and how they function in their role as mental health care providers. Also, to elicit their perceptions of barriers to the delivery of optimal mental health care. METHOD: Focus groups with standardized questions were used to elicit descriptive data, opinions, attitudes, and terminology. Convenience samples of 10 to 12 physicians were chosen in each of Ontario's 7 health care planning regions, with a mixture of rural, urban, and university settings. Discussions were audiotaped, transcribed, analyzed, and recurring themes were extracted. RESULTS: Family physicians' descriptions of the range of problems commonly encountered and their detection and management highlight the unique nature of mental health care in the primary care setting. The realities of family medicine, the undifferentiated nature of presenting problems, the long-term physician-patient relationship, and the frequent overlap of physical and mental health problems dictate an approach to diagnosis and treatment that differs from mental health care delivery in other settings. Difficulties in the relationship with local psychiatric services--accessing psychiatric care (especially for emergencies), poor communication with mental health care providers, and cumbersome intake procedures of many mental health services--were consistently identified as barriers to the delivery of optimal mental health care. CONCLUSIONS: This study confirms the importance of the family physician in the detection and management of mental health problems. It offers insights into how family physicians function in their role as mental health care providers and how they deal with diagnostic and management challenges that are specific to primary care. It also identifies barriers to the optimal delivery of mental health care in the primary care setting, including difficulties at the clinical interface between psychiatry and family medicine. Further studies are needed to explore these issues in greater depth.

Appointments and Schedules↗
PubMed1997

Cohort, gender and practice organization: examining the bounds of collaborative medicine among newly established female and male family physicians in Ontario.

This paper analyzes data from a 1993 survey of 395 newly established female and male family physicians in Ontario, Canada, to examine the relationship between practice organization and gender. Previous research suggests that younger physicians, particularly women, tend to enter group practice. Compared to solo practice, groups may offer more predictable incomes, more manageable workloads, peer collaboration and review, and economies of scale. Further, female physicians in groups may develop distinctive styles of collaborative medicine. The results show that a majority of physicians in our cohort are in private community-based group practice. However, while many groups share premises, staff and expenses, and many have common charts and practice guidelines, only a minority incorporate regular meetings to discuss business or patient care, have shared care of hospitalized patients, or audits of physicians' practices. Few gender differences are observed in private group practice: although women physicians attract larger proportions of female patients than do their male colleagues, women and men organize their groups in similar ways and have similarity strong patient-centered attitudes.

Attitude of Health Personnel↗
PubMed1997

Subtypes of ischemic stroke in children and young adults.

Specific strategies for primary and secondary stroke prevention in children and young adults can only be recommended once the causes of stroke in these age groups are well described. ICD-9 codes were used to identify children aged 1 to 18 years with acute ischemic stroke. Young adults aged > 18 to 45 years were identified from the Indiana University and Northwestern University Young Adults Stroke Registries. Validated criteria were used to subtype ischemic stroke as atherothrombotic (AT), cardioembolic (CE), small-vessel (SV), other determined cause, or unknown cause. Ninety-two children and 116 young adults were identified. Stroke subtypes in children/young adults (percentages) were as follows: AT 0/16 (p < 0.001), CE 15/14 (p = 1.0), SV 0/3 (p = 0.26), other 49/44 (p = 0.40), and unknown 36/23 (p = 0.04). Children had more prothrombotic causes (25% versus 14%, p = 0.03), and young adults had more dissections (3% versus 15%, p = 0.005). Children aged 15 to 18 years had causes of ischemic stroke more similar to those in young adults. The cause of ischemic stroke is less often identified in children than it is in young adults. Children have more prothrombotic causes of stroke, and adults have more atherothrombotic causes and dissections. Lacunar strokes are rare in both children and young adults. The age of 15 years should be used to separate childhood from young-adult ischemic stroke.

Adolescent↗