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S J Atlas

Publications and source records attributed to S J Atlas.

At least 19 recordsLinked to original sources
PubMed1998

Safely increasing the proportion of patients with community-acquired pneumonia treated as outpatients: an interventional trial.

BACKGROUND: Patients with community-acquired pneumonia who are at low risk for short-term mortality can be identified using a validated prediction rule, the Pneumonia Severity Index. Such patients should be candidates for outpatient treatment, yet many are hospitalized. OBJECTIVE: To assess a program to safely increase the proportion of low-risk patients with pneumonia treated at home. METHODS: The intervention provided physicians with the Pneumonia Severity Index score and corresponding mortality risk for eligible patients and offered enhanced visiting nurse services and the antibiotic clarithromycin. Prospectively enrolled, consecutive low-risk patients with pneumonia presenting to an emergency department during the intervention period (n = 166) were compared with consecutive retrospective controls (n = 147) identified during the prior year. A second group of 208 patients from the study hospital who participated in the Pneumonia Patient Outcomes Research Team cohort study served as controls for patient-reported measures of recovery. RESULTS: There were no significant baseline differences between patients in the intervention and control groups. The percentage initially treated as outpatients increased from 42% in the control period to 57% in the intervention period (36% relative increase; 95% confidence interval, 8%-72%; P = .01). However, more outpatients during the intervention period were subsequently admitted to the study hospital (9% vs 0%). When any admission to the study hospital within 4 weeks of presentation was considered, there was a trend toward more patients receiving all their care as outpatients in the intervention group (42% vs 52%; 25% relative increase; 95% confidence interval -2% to 59%; P = .07). No patient in the intervention group died in the 4-week follow-up period. Symptom resolution and functional status were not diminished. Satisfaction with overall care was similar, but patients treated in the outpatient setting during the intervention were less frequently satisfied with the initial treatment location than comparable control patients (71% vs 90%; P = .04). CONCLUSIONS: Use of a risk-based algorithm coupled with enhanced outpatient services effectively identified low-risk patients with community-acquired pneumonia in the emergency department and safely increased the proportion initially treated as outpatients. Outpatients in the intervention group were more likely to be subsequently admitted than were controls, lessening the net impact of the intervention.

Adult↗
PubMed1998

Time course of symptom resolution in patients with community-acquired pneumonia.

The majority of patients with community-acquired pneumonia are at low risk for short-term mortality or serious morbidity and are increasingly managed in the outpatient setting. Efforts to improve the quality of care for these patients will need to measure patient outcomes such as disease-specific symptom resolution. The aims of this study were to (1) develop a self-administered daily version of a symptom questionnaire for patients with pneumonia, (2) measure the reliability of this instrument, and (3) provide estimates for recovery rates based on symptom resolution in a cohort of low-risk patients with community-acquired pneumonia. This study was conducted as part of a prospective study of a new emergency department protocol for pneumonia at the Massachusetts General Hospital. Eligible study subjects included all adult patients with pneumonia presenting to the emergency department with a predicted low risk of short-term mortality. The main outcome measures were based on a new five item symptom questionnaire which rates the severity of cough, fatigue, dyspnea, myalgia, and fever. The questionnaires were self-administered on days 0-7, 14, 21 and 28 from the time of diagnosis of pneumonia. The symptom questions were also administered during patient interviews on days 0, 7, 14 and 28 in order to assess the questionnaire's reliability. Of the 166 eligible patients, 134 (81%) consented to participate in this study. The mean intra-class reliability coefficient of the symptom questionnaire was 0.75. The median times to resolution of individual symptoms ranged from 3 days for fever to 14 days for cough and fatigue. Thirty-five percent of patients had at least one symptom still present at the end of the 28-day study period. We found that a daily self-report questionnaire is a reliable measure of symptom resolution for patients with pneumonia. Full resolution of symptoms takes more than 28 days for a significant proportion of patients with pneumonia.

Adolescent↗
PubMed1997

Classics from the spine literature revisited: a randomized trial of 2 versus 7 days of recommended bed rest for acute low back pain.

STUDY DESIGN: Review of a trial of bed rest for patients with acute low back pain. OBJECTIVES: To assess the validity and results of the study, and their applicability to and influence on current clinical practice and recommendations. SUMMARY OF BACKGROUND DATA: Although bed rest has been a cornerstone of treatment for acute low back pain, historically this recommendation was largely based on "expert opinion." In 1986, Deyo et al. published a randomized study of 2 versus 7 days of recommended bed rest for acute low back pain. Despite results from this and other studies, current clinical practice and treatment recommendations continue to overemphasize bed rest. METHODS: The study was reviewed using structured criteria adopted from the medical literature that focus on the validity of the study design, the results of the treatment, and the relevance of the findings to clinical practice. RESULTS: Two hundred and three patients were randomized to 2 versus 7 days of recommended bed rest. Groups were similar at baseline evaluation. Outcomes assessed at 3 and 12 weeks were similar between groups, except that patients receiving a recommendation for 2 days of bed rest had significantly fewer days of work absence than those recommended 7 days. Limitations of the study included poor compliance with recommended bed rest, especially in the 7-day group, a marginal sample size without information on relevant confidence intervals, and patient characteristics that may have affected the generalizability of these findings to others with acute low back pain. CONCLUSIONS: Despite limitations, this study provided strong evidence that less bed rest was associated with similar outcomes for acute low back pain along with quicker return to work. Results from this and other studies support a shift away from bed rest as a primary recommendation in the initial management of low back pain. In spite of this, bed rest recommendations for episodes of low back pain remain common. Additional efforts are needed to change clinical practice.

Absenteeism↗
PubMed1996

The Quebec Task Force classification for Spinal Disorders and the severity, treatment, and outcomes of sciatica and lumbar spinal stenosis.

STUDY DESIGN: A prospective cohort study of patients in Maine with sciatica and lumbar spinal stenosis treated surgically and nonsurgically. SUMMARY OF BACKGROUND DATA: In 1987, the Quebec Task Force on Spinal Disorders proposed a diagnostic classification to help make clinical decisions, evaluate quality of care, assess prognosis, and conduct research. OBJECTIVES: To assess the Quebec Task Force classification's ability to stratify patients according to severity and treatment at baseline, and to assess changes over time in health-related quality of life, including symptoms, functional status, and disability. METHODS: Five hundred sixteen patients participating in the Maine Lumbar Spine Study who completed baseline and 1-year follow-up evaluations were classified successfully according to the Quebec Task Force classification. Patient characteristics and treatments were compared across Quebec Task Force classification categories. Changes in health-related quality of life over 1 year were assessed according to Quebec Task Force classification category and type of treatment. RESULTS: Among patients with sciatica (n = 370), higher Quebec Task Force classification categories (from 2, pain radiating to the proximal extremity, to 6, sciatica with evidence of nerve root compression) were associated with increased severity of symptoms at baseline. There was no association between Quebec Task Force classification and baseline functional status. Quebec Task Force classification was associated strongly with the likelihood of receiving surgical treatment (P < or = 0.005). Among patients with sciatica treated nonsurgically, improvement at 1 year in back-specific and generic physical function increased with higher Quebec Task Force classification category (P < or = 0.05). Only a nonsignificant trend was observed for surgically treated patients. Patients with lumbar spinal stenosis (Quebec Task Force classification 7, n = 131) had baseline features and outcomes distinct from patients with sciatica. CONCLUSIONS: For patients with sciatica, the Quebec Task Force classification was highly associated with the severity of symptoms and the probability of subsequent surgical treatment. Nonsurgically treated patients in Quebec Task Force classification categories reflecting nerve root compression had greater improvement than those with pain symptoms alone. Among surgical patients, the Quebec Task Force classification was not associated with outcome. These results provide validation for the classification and its wider adoption. Nonetheless, improved diagnostic classifications are needed to predict outcomes better in patients with sciatica who undergo surgery.

Adolescent↗
PubMed1996

The Maine Lumbar Spine Study, Part I. Background and concepts.

STUDY DESIGN: This paper describes the background and factors that led to the development and implementation of the Maine Lumbar Spine Study, a prospective cohort study of patients undergoing surgical and nonsurgical treatment of herniated lumbar disc with sciatica and symptomatic spinal stenosis. OBJECTIVES: To define the factors leading to the study and the methods of designing and implementing a community-based effectiveness study to evaluate the outcomes of herniated lumbar intervertebral disc and spinal stenosis. SUMMARY OF BACKGROUND DATA: Variations in the utilization of surgery for these conditions and physicians' uncertainty regarding the best way to manage them resulted in support of a community-based study of the effectiveness of treatment alternatives. METHODS: A prospective cohort design was used. Methods of patient enrollment, data collection, management, and analysis are described. An innovative method of ascertaining the representativeness of the enrolled versus nonenrolled patient population is presented. RESULTS: The importance of developing community-based networks of physicians is discussed. CONCLUSIONS: These networks play an important role in analyzing practice pattern variations and in stimulating and participating in effectiveness research. Because effectiveness studies must be conducted at the community level, mechanisms must be developed with which to support and implement these efforts.

Cohort Studies↗
PubMed1996

The Maine Lumbar Spine Study, Part II. 1-year outcomes of surgical and nonsurgical management of sciatica.

STUDY DESIGN: The Maine Lumbar Spine Study is a prospective cohort study of patients recruited from the practices of orthopedic surgeons, neurosurgeons, and occupational medicine physicians throughout Maine. OBJECTIVE: To assess 1-year outcomes of patients with sciatica believed to be due to a herniated lumbar disc treated surgically or nonsurgically. SUMMARY OF BACKGROUND DATA: Lumbar spine surgery rates vary by geographic region and may reflect uncertainty about optimal clinical use. METHODS: Eligible consenting patients participated in a baseline interview performed by study personnel and then were mailed follow-up questionnaires at 3, 6, and 12 months. Clinical data were obtained from a physician questionnaire. Outcomes included patient-reported symptoms of leg and back pain, functional status, disability, quality of life, and satisfaction with care. RESULTS: Five hundred seven patients with sciatica, 275 treated surgically and 232 treated nonsurgically initially, were enrolled. Surgically treated patients, on average, had more severe symptoms and had more severe physical and imaging findings than nonsurgically treated patients at entry. Although few surgically treated patients had mild symptoms and few nonsurgically treated patients had severe symptoms, about half in each treatment group had symptoms that fell into a moderate category. At the 1-year evaluation, improvement in symptoms, functional status, and disability were found in both treatment groups. However, surgically treated patients reported significantly greater improvement. For the predominant symptom, either back or leg pain, 71% of surgically treated and 43% of nonsurgically treated patients reported definite improvement (P < 0.001). This effect was even greater after adjustment for differences between treatment groups at entry (relative odds of definite improvement, 4.3; P < 0.001). For patients with moderate symptoms and abnormal physical examination findings, surgical treatment also resulted in greater improvement than nonsurgical treatment. However, there was little difference in the employment or workers' compensation status of patients treated surgically versus nonsurgically (5% vs. 7% unemployed at 1-year follow-up if employed at entry [P = 0.68]; 46% vs. 55% receiving workers' compensation at 1-year follow-up if receiving it at entry [P = 0.30] for surgical and nonsurgical management, respectively). For patients with mild symptoms, the benefits of surgical and nonsurgical treatment were similar. CONCLUSIONS: Although surgically treated patients were on average more symptomatic at entry, there was substantial overlap in symptoms between surgically treated and nonsurgically treated patients. Surgically treated patients with sciatica reported substantially greater improvement at 1-year follow-up. However, employment and compensation outcomes were similar between the two treatment groups, and surgery appeared to provide little advantage for the subset of patients with mild symptoms. These results should be interpreted cautiously, because surgical treatment was not assigned randomly. Long-term follow-up will determine if these differences persist.

Adolescent↗
PubMed1996

The Maine Lumbar Spine Study, Part III. 1-year outcomes of surgical and nonsurgical management of lumbar spinal stenosis.

STUDY DESIGN: A prospective cohort study of patients with lumbar spinal stenosis recruited from the practices of orthopedic surgeons and neurosurgeons throughout Maine. OBJECTIVE: To assess 1-year outcomes of patients with lumbar spinal stenosis treated surgically or nonsurgically. SUMMARY OF BACKGROUND DATA: No randomized trials and few nonexperimental studies have compared surgical and nonsurgical treatment of patients with lumbar spinal stenosis. The authors' goal was to assess 1-year outcomes of patients with lumbar spinal stenosis treated surgically or nonsurgically. METHODS: Eligible, consenting patients participated in baseline interviews and were then mailed follow-up questionnaires at 3, 6, and 12 months. Clinical data were obtained from a physician questionnaire. Outcomes included patient-reported symptoms of leg and back pain, functional status, disability, and satisfaction with care. RESULTS: One hundred forty-eight patients with lumbar spinal stenosis were enrolled, of whom 81 were treated surgically and 67 treated nonsurgically. On average, patients in the surgical group had more severe imaging findings and symptoms and worse functional status than patients in the nonsurgical group at entry. Few patients with mild symptoms were treated surgically, and few patients with severe symptoms were treated nonsurgically. However, of the patients with moderate symptoms, a similar percent were treated surgically or nonsurgically. One year after study entry, 28% of nonsurgically and 55% of surgically treated patients reported definite improvement in their predominant symptoms (P = 0.003). For patients with moderate symptoms, outcomes for surgically treated patients were also improved compared with those of nonsurgically treated patients. Surgical treatment remained a significant determinant of 1-year outcome, even after adjustment for differences between treatment groups at entry (P = 0.05). The maximal benefit of surgery was observed by the time of the first follow-up evaluation, which was at 3 months. Although few nonsurgically treated patients experienced a worsening of their condition, there was little improvement in symptoms and functional status compared with study entry. CONCLUSIONS: At a 1-year evaluation of patient-reported outcomes, patients with severe lumbar spinal stenosis who were treated surgically had greater improvement than patients treated nonsurgically. Comparisons of outcomes by treatment received must be made cautiously because of differences in baseline characteristics. A determination of whether the outcomes observed persist requires long-term follow-up.

Adult↗
PubMed1996

Application of outcomes research in occupational low back pain: the Maine Lumbar Spine Study.

Outcomes research represents an expansion of traditional clinical research to include issues of cost and quality of care in usual clinical practice, emphasizing outcomes that matter most to patients. In low back disorders, outcomes research has focused on the lack of reliable information to support much of clinical practice and has demonstrated marked variability in the treatment of these common problems. The Maine Lumbar Spine Study represents an example of an outcomes research study to investigate the treatment of patients with sciatica in usual clinical practice. Because low back symptoms are a frequent cause of occupational disability, Workers' Compensation patients were explicitly oversampled. Baseline features were significantly different in those patients who were receiving Workers' Compensation versus those who were not. Efforts to compare outcomes by disability status need to control for these differences. Whereas most Workers' Compensation patients were still receiving disability compensation regardless of treatment at 6 months, patients who were treated surgically were more likely to have come off disability and returned to work than nonsurgically treated patients. Long-term follow-up is necessary to determine whether these differences persist.

Adult↗
PubMed1995

Assessing health-related quality of life in patients with sciatica.

STUDY DESIGN: This study analyzed health-related quality-of-life measures and other clinical and questionnaire data obtained from the Maine Lumbar Spine Study, a prospective cohort study of persons with low back problems. OBJECTIVE: For persons with sciatica, back pain-specific and general measures of health-related quality-of-life were compared with regard to internal consistency, construct validity, reproducibility, and responsiveness in detecting small changes over a 3-month period. SUMMARY OF BACKGROUND DATA: Data were collected from 427 participants with sciatica. Baseline in-person interviews were conducted with surgical and medical patients before treatment and by mail at 3 months. METHODS: Health-related quality-of-life measures included symptoms (frequency and bothersomeness of pain and sciatica) functional status and well-being (modified back pain-specific Roland scale and Medical Outcomes Study 36-item Short Form Health Survey (SF-36), and disability (bed rest, work loss, and restricted activity days). RESULTS: Internal consistency of measures was high. Reproducibility was moderate, as expected after a 3-month interval. The SF-36 bodily pain item and the modified Roland measure demonstrated the greatest amount of change and were the most highly associated with self-rated improvement. The specific and generic measures changed in the expected direction, except for general health perceptions, which declined slightly. A high correlation between clinical findings or symptoms and the modified Roland measure, SF-36, and disability days indicated a high degree of construct validity. CONCLUSIONS: These measures performed well in measuring the health-related quality-of-life of patients with sciatica. The modified Roland and the physical dimension of the SF-36 were the measures most responsive to change over time, suggesting their use in prospective evaluation. Disability day measures, although valuable for assessing the societal impact of dysfunction, were less responsive to changes over this short-term follow-up of 3 months.

Adolescent↗
PubMed1994

Changing blood use in the AIDS era: the case of elective hip surgery.

BACKGROUND: Concern about the transmission of human immunodeficiency virus via blood has substantially increased the public's anxiety about the safety of the blood supply and has encouraged practices to minimize risks deriving from transfusions. STUDY DESIGN AND METHODS: To assess changes in transfusion practices in elective surgery as awareness of transfusion-transmitted human immunodeficiency virus emerged, 80 randomly selected patients per year undergoing elective total hip replacement in five calendar years between 1977 and 1989 at a large university teaching hospital were studied. RESULTS: Total blood use decreased significantly from an average of 3.3 units per patient in 1977 to 2.1 units per patient in 1989 (p = 0.0003). Autologous blood use increased from essentially zero in 1977 to 82 percent of total blood use in 1989 (p < 0.0001). The threshold hematocrit for postoperative transfusion of allogeneic blood (defined by use of logistic regression models) decreased from 30.1 percent (0.30) in 1977 to 26.7 percent (0.27) in 1989 (p = 0.01). As a result of these changes, the proportion of patients exposed to allogeneic blood decreased from 90 to 16 percent across the study period (p < 0.0001). The dramatic decrease in the use of allogeneic blood in elective total hip replacement surgery during the study period was due to decreased demand for blood during and after the operation and to a striking shift in the blood supply from allogeneic to autologous sources. CONCLUSION: These findings demonstrate that physicians can appropriately alter practices when there are perceived health risks.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Inhibition of gonadotrophin-induced ovulation in rabbits by perfusion with dibutyryl cAMP via reduction of ovarian prostaglandin production.

The role of cAMP in ovulation, oocyte maturation and prostaglandin production was assessed using a rabbit ovary preparation perfused in vitro. Dibutyryl cAMP (10(-3), 10(-4) or 10(-5) mol l-1) was added to the perfusate of one ovary. The contralateral, control ovary was perfused with medium alone. Thirty minutes after the onset of perfusion, 50 iu hCG was added to the perfusate of all ovaries. Dibutyryl cAMP inhibited hCG-induced ovulation in a dose-related fashion. No difference in ovum maturity or degeneration was found between control ovaries and ovaries treated with dibutyryl cAMP. Ovarian progesterone production was not affected by exposure to dibutyryl cAMP. The concentrations of 6-keto PGF1 alpha (the stable metabolite of prostacyclin) and PGF2 alpha in the perfusate of ovaries treated with dibutyryl cAMP were 49.6% and 32.0% of the control values, respectively, 12 h after hCG administration. Inhibition of 6-keto PGF1 alpha production by dibutyryl cAMP was dose related. Production of PGE2 was unaffected by dibutyryl cAMP. These data raise the possibility that continuous exposure to dibutyryl cAMP may inhibit hCG-induced ovulation in the perfused rabbit ovary via a reduction in PGF2 alpha and prostacyclin production.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Epidermal growth factor inhibits follicular response to human chorionic gonadotropin: possible role of cell to cell communication in the response to gonadotropin.

Epidermal growth factor (EGF) affects follicular steroidogenesis and expression of gonadotropin receptors. The effects of EGF on hCG-induced estradiol and progesterone secretion and ovulation were examined in the in vitro perfused rabbit ovary. We also examined the effects of EGF on hCG-induced progesterone secretion by isolated granulosa cells. In addition, distribution of hCG within the follicle was probed by immunohistochemical means 30 min after its administration to the in vitro perfused ovary. EGF significantly (P less than 0.05) reduced hCG-induced secretion of estradiol (control, 117 +/- 12 pg/min.follicle; 10 ng/ml EGF, 55 +/- 10) and progesterone (control, 18.2 +/- 1.2 ng/min.follicle; 10 ng/ml EGF, 11.9 +/- 0.8) by the perfused ovary. In contrast, EGF did not inhibit hCG-induced progesterone secretion by isolated granulosa cells. Ovulatory efficiency (number of ovulated ova per number of mature follicles x 100) when EGF was given 30 min before hCG was reduced dose-dependently from 58.2% with no EGF to 8.3% with 10 ng/ml EGF (P less than 0.001). Ovulation was not inhibited by EGF when it was given 30 min after hCG. Distribution of hCG in the preovulatory follicle was confined to the basement membrane, thecal cell layer, and a small fraction of the outer granulosa cell layer. These observations suggest that gonadotropin stimulates the follicle through the release of a secondary signal(s) from ligand-bound granulosa cells near the follicle wall to unexposed cells of the inner avascular area. EGF may inhibit the follicular response to hCG by attenuation of this cell to cell communication.

Animals↗
PubMed1991

Effects of intravenous cocaine on reproductive function in the mated rabbit.

A dramatic increase in the use of crack cocaine by young women has resulted in the exposure of a substantial number of fetuses to the drug in utero. The goal of these experiments was to investigate the effects of intravenous cocaine (a model for crack) on reproductive function in the female rabbit. We used two protocols: (1) single daily injections over the course of pregnancy ("single daily" protocol), with animals examined on day 1, 8, 15, 22, or 29, and (2) six hourly injections on the day of mating ("binge" protocol). The maximum tolerated dose of cocaine, 4 mg/kg, was administered at 0.5 ml/min. The single daily protocol increased ovulation but had no effect on fetal and placental weights or preterm delivery. The binge protocol significantly reduced in vitro development of retrieved embryos but did not affect implantation assessed on day 8 of pregnancy.

Animals↗
PubMed1991

Do prostaglandins lead to ovulation in the rabbit by stimulating proteolytic enzyme activity?

OBJECTIVE: To determine if prostaglandins (PGs) have a direct effect on the ovarian proteolytic enzyme system by examining ultrastructure of the follicle wall and the microvasculature in the presence and absence of indomethacin and by using the isolated perfused rabbit ovary. DESIGN: Nine hours after administration of human chorionic gonadotropin (hCG) or hCG plus indomethacin, follicles were removed and processed for scanning and transmission electron microscopy. Isolated perfused rabbit ovaries were induced to ovulate with PGF2 alpha (100 ng/mL) in the presence and absence of tranexamic acid (0.1, 1.0, or 10 mM), a plasminogen activator inhibitor. RESULTS: The addition of indomethacin to hCG inhibited ovulation and production of PGs without affecting the follicular microvasculature. However, the changes in follicle wall architecture were less pronounced after treatment with indomethacin. Ovulatory efficiency in response to PGF2 alpha (the percent of follicles greater than 1.5 mm that ovulate) was significantly reduced (P less than 0.01) by 10 mM tranexamic acid. CONCLUSIONS: These results suggest that PGs induce follicular rupture by activation of proteolytic enzymes located in the follicle wall.

Animals↗
PubMed1991

Effect of inhibition of oxygen free radical on ovulation and progesterone production by the in-vitro perfused rabbit ovary.

The potential role of oxygen free radicals in hCG-induced ovulation was investigated using the free radical scavenging enzymes superoxide dismutase (SOD) and/or catalase with the in-vitro perfused rabbit ovary preparation. SOD (25 micrograms/ml) and SOD + catalase (25 micrograms/ml) significantly reduced the % of large follicles that ovulated during perfusion (P less than 0.005). Neither maturity nor degeneration of ovulated ova and follicular oocytes was affected by SOD and/or catalase. Progesterone concentration in the perfusate was significantly increased in the SOD + catalase treatment group (P less than 0.01). These results indicate a significant role for oxygen free radicals in the process of ovulation.

Animals↗
PubMed1991

Direct effect of angiotensin II on in-vitro perfused rabbit ovary.

The effects of angiotensin II (AII) and its receptor blocker, saralasin (SAR), on ovulation and oocyte maturation were investigated in an isolated, in-vitro perfused rabbit ovary. Ovulation and oocyte maturation were induced by AII in the absence of human chorionic gonadotrophin (hCG). SAR inhibited ovulation induced by AII or hCG, but not oocyte maturation. AII appears to play a critical role in follicle rupture, but not in resumption of oocyte meiosis.

Angiotensin II↗