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M B Bracken

Publications and source records attributed to M B Bracken.

At least 73 records · Page 4Linked to original sources
PubMed1993

Possible role of asthma in the risk of preterm labor and delivery.

We assessed the relation between maternal respiratory problems and preterm labor and delivery in a cohort of 3,891 women who delivered a singleton livebirth. Study participants were asked about their medical history in the 12 months before conception; women who reported a history of asthma had a higher risk of preterm labor [relative risk (RR) estimate = 2.33, 95% confidence interval (CI) = 1.03-5.26]. Asthmatic women also had an increased risk of preterm delivery (RR = 1.77, 95% CI = 0.60-5.24). Maternal respiratory problems during pregnancy were also associated with an increased risk of both inhibited preterm labor (RR = 2.14, 95% CI = 1.25-3.66) and preterm delivery (RR = 2.03, 95% CI = 1.08-3.82). Birthweight appeared to be unrelated to maternal history of asthma. Logistic regression models that adjusted for potential confounders did not appreciably alter the results. The adjusted odds ratio (OR) estimate for the odds of preterm labor in asthmatics relative to nonasthmatics is 2.42 (95% CI = 0.90-6.54); the analogous OR estimate for those with respiratory problems during pregnancy is 2.16 (95% CI = 1.14-4.10). The adjusted OR estimate for the odds of preterm delivery in asthmatics is 1.78 (95% CI = 0.53-6.02); for those with respiratory problems during pregnancy, the corresponding estimate is 2.00 (95% CI = 0.92-4.13).

Adult↗
PubMed1993

Effects of timing of methylprednisolone or naloxone administration on recovery of segmental and long-tract neurological function in NASCIS 2.

Previous analyses of the National Acute Spinal Cord Injury Study (NASCIS) have not distinguished recovery of segmental function at the injury level from recovery of the long spinal tracts. Recovery at the injury level could be of considerable clinical significance, but long-tract recovery is the ultimate therapeutic goal. This analysis demonstrates that the greatest proportion of all neurological recovery and of recovery due to treatment with very high doses of methylprednisolone within 8 hours of injury occurs below the lesion. Methylprednisolone treatment administered early following injury has been found to improve recovery below the lesion in patients initially diagnosed as having complete or incomplete injuries; it also leads to greater (but still relatively small) improvement in the injury level. The analysis indicates that delayed treatment with methylprednisolone is associated with decreased neurological recovery. Naloxone administration also improved neurological function below the lesion in patients with incomplete injuries; these results support further experimental work with this drug. This observation of differential neurological response within a narrow treatment window has important implications for both experimental studies and clinical management. Early clinical management with high-dose methylprednisolone is supported by this analysis.

Drug Administration Schedule↗
PubMed1993

Maternal age: an independent risk factor for cesarean delivery.

OBJECTIVE: To evaluate whether there is an increased risk of cesarean delivery in women who delay childbearing into their later reproductive years, using a well-defined cohort and controlling for difference in baseline susceptibility such as complications of pregnancy and labor. METHODS: The current study included all women at least 20 years of age delivering their first child and evaluated between 1988-1991 as part of the prospective Yale Health in Pregnancy Study (N = 735). All women planned to deliver at Yale-New Haven Hospital. The study group was divided into three maternal age groups: 20-29 (N = 422), 30-34 (N = 239), and 35 and over (N = 74). Information collected included demographic characteristics, medical history, pregnancy complications, labor complications, mode of delivery, and pregnancy outcome. RESULTS: The cesarean delivery rates for the three age groups were 16.8% (71 of 422), 26.8% (64 of 239), and 32.4% (24 of 74), respectively. This trend was highly significant when evaluated with chi 2 for linear trend (P = .0002). Within groups of women with and without complications of pregnancy or labor, cesarean rates increased with maternal age. Using stepwise logistic regression to adjust simultaneously for confounding variables, adjusted odds ratios were 1.6 (95% confidence interval [CI] 0.9-2.7) for the women aged 30-34 and 2.3 (95% CI 1.1-4.8) for the 35 and older age group. CONCLUSIONS: Maternal age appears to be an independent risk factor for cesarean delivery. The reasons for this clinically important and statistically significant increased risk are unclear, but may be due to physician and patient concern over pregnancy outcome in older women.

Adult↗
PubMed1993

Pharmacological treatment of acute spinal cord injury: current status and future projects.

The multicenter, double-blind, randomized second National Acute Spinal Cord Injury Study (NASCIS 2) was conducted to assess the effectiveness of methylprednisolone in improving neurological function after acute spinal cord injury. At 6 weeks, patients treated within 8 hours of injury with methylprednisolone, given as an initial bolus of 30 mg/kg followed by infusion of 5.4 mg/kg/h over 23 hours, demonstrated significantly greater improvement in motor function and touch sensation than did those receiving either naloxone or placebo. Improvement in pinprick sensation was also greater in the methylprednisolone group. These differences were maintained at 6 months and 1 year after injury. The recovery of motor and sensory function in methylprednisolone-treated patients was found to be due primarily to reductions in the severity of the lesion in the spinal cord itself rather than to improvements in the level of injury or root function. A new trial, NASCIS 3, is evaluating a 48-hour course of methylprednisolone infusion as well as treatment with tirilazad mesylate, an inhibitor of lipid peroxidation without glucocorticoid activity.

Adult↗
PubMed1992

A model for estimating level and net severity of spinal cord injuries.

Objective and detailed neurological assessments are essential in studies of the treatment and the epidemiology of acute spinal cord injuries. In practice, investigators use the expanded score, found by taking the total of the individual determinations, but this summary obscures important detail as to the level and the overall severity of injury. To address this issue, we present a method for estimating level and net severity of injury that makes use of isotonic regression and the Spearman-Kärber estimator. We describe the method for both sensory and motor assessments of neurologic function. In the special case where one gives an identical weight to the response at each level, these estimators algebraically partition the expanded score into separate contributions due to level and net severity. We provide a numerical example using data from the first National Acute Spinal Cord Injury Study, and we present a summary of the distribution of these parameters for this population.

Evaluation Studies as Topic↗
PubMed1992

The relationship between acute inflammatory lesions of the preterm placenta and amniotic fluid microbiology.

OBJECTIVE: Our objective was to determine the relationship between microbial invasion of the amniotic cavity and the presence and severity of acute inflammatory lesions in the placenta. STUDY DESIGN: Placental histologic and amniotic fluid microbiologic studies were performed in 92 consecutive patients who were admitted with preterm labor and intact membranes and delivered within 48 hours after amniocentesis. RESULTS: The prevalence of a positive amniotic fluid culture was 38% (35 of 92). There was a strong association between the presence and severity of inflammation in the amnion, chorion-decidua, umbilical cord, and chorionic plate and the results of the amniotic fluid culture (p less than 0.0001 for each tissue section). Three patterns of inflammation of the chorion-decidua were identified: marginating, nonmarginating, and a mixed pattern. The marginating and the mixed patterns of inflammation were strongly associated with the presence of a positive amniotic fluid culture. Acute inflammation of the chorionic plate was the most sensitive indicator of a microbial invasion of the amniotic cavity (sensitivity 96.6%), and funisitis and umbilical vasculitis had the highest specificity (85.7%). CONCLUSION: The presence of acute inflammatory lesions of the chorioamniotic membranes can serve as a marker of microbial invasion of the amniotic cavity.

Amnion↗
PubMed1992

Methylprednisolone or naloxone treatment after acute spinal cord injury: 1-year follow-up data. Results of the second National Acute Spinal Cord Injury Study.

The 1-year follow-up data of a multicenter randomized controlled trial of methylprednisolone (30 mg/kg bolus and 5.4 mg/kg/hr for 23 hours) or naloxone (5.4 mg/kg bolus and 4.0 mg/kg/hr for 23 hours) treatment for acute spinal cord injury are reported and compared with placebo results. In patients treated with methylprednisolone within 8 hours of injury, increased recovery of neurological function was seen at 6 weeks and at 6 months and continued to be observed 1 year after injury. For motor function, this difference was statistically significant (p = 0.030), and was found in patients with total sensory and motor loss in the emergency room (p = 0.019) and in those with some preservation of motor and sensory function (p = 0.024). Naloxone-treated patients did not show significantly greater recovery. Patients treated after 8 hours of injury recovered less motor function if receiving methylprednisolone (p = 0.08) or naloxone (p = 0.10) as compared with those given placebo. Complication and mortality rates were similar in either group of treated patients as compared with the placebo group. The authors conclude that treatment with the study dose of methylprednisolone is indicated for acute spinal cord trauma, but only if it can be started within 8 hours of injury.

Acute Disease↗
PubMed1992

The Second National Acute Spinal Cord Injury Study.

In 1990, the Second National Acute Spinal Cord Injury Study reported that high-dosage methylprednisolone improves neurologic recovery in spinal-injured humans. The study showed that patients who received the drug within 8 hr after injury improved, whereas those who received the drug later did not. The drug significantly increased recovery even in severely injured patients who were admitted with no motor or sensory function below the lesion, contradicting a long-held dogma that such patients would not recover. Some researchers, however, have questioned the stratification of the patient population, the use of summed neurologic change scores, and the absence of functional assessments. The stratification by injury severity and treatment time was planned a priori and based on objective criteria. Detailed analyses revealed no differences between groups attributable to stratification or randomization. While multivariate analyses of the summed neurologic scores were used, the conclusions were corroborated by other analytical approaches that did not rely on summed scores. For example, treatment with methylprednisolone more than doubled the probability that patients would convert from quadriplegia or paraplegia to quadriparesis or paraparesis, analgesia to hypalgesia, and anesthesia to hypesthesia. The treatment also significantly improved neurologic scores in lumbosacral segments, indicating that beneficial effects were not limited to segments close to the lesion site. The treatment did not significantly affect mortality or morbidity. The study strongly suggests that methylprednisolone has significant beneficial effects in human spinal cord injury, that these effects occur only when the drug is given within 8 hr, and that it helps even in patients with severe spinal cord injuries. These conclusions have important implications for spinal cord injury care and research.

Drug Administration Schedule↗
PubMed1991

Medication in early pregnancy: prevalence of use and relationship to maternal characteristics.

Medication use was assessed in a population of 4186 women who were delivered of infants at Yale-New Haven Hospital, New Haven, Connecticut, between 1980 and 1982. The frequency of over-the-counter and prescription drug use, and the association of such use with maternal characteristics was studied. Of all women, 66% used at least one drug. The mean number of drugs used by all subjects was 1.3 and, among drug users, 2.9. Of all drugs used, 68% were over-the-counter and 32% were prescription preparations. Internal analgesics, autonomic drugs, antiinfective agents, and antacids were most frequently used. Women who used prescription drugs were also more likely to use over-the-counter medications. Maternal characteristics that were associated with an increase in both over-the-counter and prescription drug use were being white, smoking more than 20 cigarettes a day, using alcohol, using caffeine, and smoking marijuana. These findings suggest that women who engage in "risk-taking behavior" during pregnancy are also more likely to use medications while pregnant.

Adult↗
PubMed1991

Treatment of acute spinal cord injury with methylprednisolone: results of a multicenter, randomized clinical trial.

Although some evidence of neurological improvement with naloxone exists in this trial, the improvement was never significantly better than that seen for placebo. Methylprednisolone (MP) was effective in reducing some of the permanent paralysis after acute spinal cord injury at the doses studied, but only when treatment began within 8 h after injury. There is currently no support for the administration of higher or lower doses of the drug and an apparent contraindication to initiating administration of MP at any dose more than 8 h after injury.

Acute Disease↗
PubMed1990

A randomized, controlled trial of methylprednisolone or naloxone in the treatment of acute spinal-cord injury. Results of the Second National Acute Spinal Cord Injury Study.

Studies in animals indicate that methylprednisolone and naloxone are both potentially beneficial in acute spinal-cord injury, but whether any treatment is clinically effective remains uncertain. We evaluated the efficacy and safety of methylprednisolone and naloxone in a multicenter randomized, double-blind, placebo-controlled trial in patients with acute spinal-cord injury, 95 percent of whom were treated within 14 hours of injury. Methylprednisolone was given to 162 patients as a bolus of 30 mg per kilogram of body weight, followed by infusion at 5.4 mg per kilogram per hour for 23 hours. Naloxone was given to 154 patients as a bolus of 5.4 mg per kilogram, followed by infusion at 4.0 mg per kilogram per hour for 23 hours. Placebos were given to 171 patients by bolus and infusion. Motor and sensory functions were assessed by systematic neurological examination on admission and six weeks and six months after injury. After six months the patients who were treated with methylprednisolone within eight hours of their injury had significant improvement as compared with those given placebo in motor function (neurologic change scores of 16.0 and 11.2, respectively; P = 0.03) and sensation to pinprick (change scores of 11.4 and 6.6; P = 0.02) and touch (change scores, 8.9 and 4.3; P = 0.03). Benefit from methylprednisolone was seen in patients whose injuries were initially evaluated as neurologically complete, as well as in those believed to have incomplete lesions. The patients treated with naloxone, or with methylprednisolone more than eight hours after their injury, did not differ in their neurologic outcomes from those given placebo. Mortality and major morbidity were similar in all three groups. We conclude that in patients with acute spinal-cord injury, treatment with methylprednisolone in the dose used in this study improves neurologic recovery when the medication is given in the first eight hours. We also conclude that treatment with naloxone in the dose used in this study does not improve neurologic recovery after acute spinal-cord injury.

Acute Disease↗
PubMed1990

Association of cocaine use with sperm concentration, motility, and morphology.

Use of cocaine within 2 years of their first semen analysis has been found to be twice as common among men with sperm counts less than 20 X 10(6) mL (odds ratio [OR] = 2.1, 95% confidence interval [CI] 1.0, 4.6). Duration of cocaine use for five or more years was more common in men with low sperm motility (OR = 2.0, 95% CI 1.0, 4.1) and in those with low concentrations and a large proportion of abnormal forms. Other major risk factors for these three indicators of male subfertility also have been identified, but the cocaine risk factors remained after adjustment for them. This association, together with the high prevalence of cocaine use in the general male population, suggests cocaine may now be related to male subfertility and that history of use should be ascertained during diagnostic interviews.

Adult↗