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M S Kramer

Publications and source records attributed to M S Kramer.

At least 73 records · Page 4Linked to original sources
PubMed1999

Are all growth-restricted newborns created equal(ly)?

BACKGROUND: Previous etiologic studies have defined intrauterine growth restriction (IUGR) based on a single cutoff. OBJECTIVE: To assess the relative importance of known etiologic determinants for different degrees (mild versus severe) and timing (preterm versus term) of fetal growth restriction. DESIGN: Hospital-based cohort study. SETTING: Tertiary-care university hospital. PARTICIPANTS: Sixty-five thousand two hundred eighty inborn singleton infants without major congenital anomalies delivered between January 1, 1978 and March 31, 1996. MEASUREMENTS: Comparison of adjusted odds ratios (ORs) and 95% confidence intervals for mild IUGR (defined as birth weight 75% to <85% of the mean for gestational age, the latter cutoff equivalent to the 9.9th percentile for this cohort) and severe IUGR (<75% of mean, or 2.3rd percentile), after controlling for maternal age, education, marital status, and other potential determinants by means of multiple logistic regression. RESULTS: Maternal prepregnancy overweight (body mass index [BMI] >26.0-29.0 kg/m2) and obesity (BMI >29.0 kg/m2) had stronger protective effects against mild IUGR than against severe IUGR, but most of the determinants showed the opposite pattern. This was especially true for pathologic determinants; ORs (and 95% confidence intervals) for severe versus mild IUGR were 18.5 (14.5-23.8) vs 4.6 (3.6-5.8) for severe pregnancy-induced hypertension (PIH), 3.5 (2.2-5.5) vs 2.3 (1. 5-3.4) for prepregnancy hypertension, and 3.4 (2.9-3.9) vs 2.2 (2. 0-2.4) for smoking >/=11 cigarettes/day. Primiparity, short stature, prepregnancy BMI, maternal weight gain, and cigarette smoking had significantly larger effects on term IUGR, whereas the effect of severe PIH was more than twice as large for preterm IUGR (OR = 9.7 [7.3-13.0]) as for term IUGR (OR = 4.0 [3.0-5.3]). CONCLUSION: Pathologic determinants of IUGR such as prepregnancy and PIH and cigarette smoking predispose to more severe fetal growth retardation, and PIH in particular seems to do so before 37 weeks. Growth-restricted newborns are not, therefore, all created equal(ly).

Adult↗
PubMed1998

Secular trends in preterm birth: a hospital-based cohort study.

CONTEXT: Canada and the United States have reported a recent increase in the incidence of preterm birth, but the reasons for this increase are unknown. OBJECTIVE: To assess secular trends in preterm birth and its potential determinants. DESIGN: Hospital-based cohort study. SETTING: Canadian tertiary care university teaching hospital, 1978-1996. PARTICIPANTS: A total of 65574 nonreferred live births and stillbirths. MAIN OUTCOME MEASURES: Changes in occurrence of preterm birth, before and after adjustment for changes in method of gestational age assessment, obstetric intervention, registration of births weighing less than 500 g, and sociodemographic, behavioral, and clinical determinants. RESULTS: A crude secular increase in preterm births was seen for births less than 37, 34, and 32 completed weeks using 3 alternative gestational age estimation methods. Based on an algorithm incorporating both menstrual and early ultrasound gestational age estimates, rates increased from 6.6% to 9.8% for births at less than 37 weeks' gestation, 1.7% to 2.3% at less than 34 weeks, and 1.0% to 1.2% at less than 32 weeks. Exclusion of births weighing less than 500 g and those with induction or preterm cesarean delivery without labor before each of the corresponding gestational age cutoffs eliminated the secular trends for births before 34 and 32 weeks and attenuated the trend for births before 37 weeks. Nearly half of the remaining trend for births before 37 weeks was accounted for by the increasing use of early ultrasound dating. The residual trend was eliminated after controlling for secular increases in unmarried status and the proportion of women aged 35 years or older. These factors, combined with a decrease in alcohol consumption and increases in histological chorioamnionitis and cocaine use, appear to have counteracted a reduction in preterm birth since the mid-1980s that otherwise would have been observed. CONCLUSIONS: This hospital's increase in preterm births since 1978 parallels increases reported in population-based national studies from the United States and Canada. This trend appears largely attributable to the increasing use of early ultrasound dating, preterm induction and preterm cesarean delivery without labor, and changes in sociodemographic and behavioral factors.

Canada↗
PubMed1998

Determinants of preterm birth rates in Canada from 1981 through 1983 and from 1992 through 1994.

BACKGROUND: The rates of preterm birth have increased in many countries, including Canada, over the past 20 years. However, the factors underlying the increase are poorly understood. METHODS: We used data from the Statistics Canada live-birth and stillbirth data bases to determine the effects of changes in the frequency of multiple births, registration of births occurring very early in gestation, patterns of obstetrical intervention, and use of ultrasonographic dating of gestational age on the rates of preterm birth in Canada from 1981 through 1983 and from 1992 through 1994. All births in 9 of the 12 provinces and territories of Canada were included. Logistic-regression analysis and Poisson regression analysis were used to estimate changes between the two three-year periods, after adjustment for the above-mentioned determinants of the likelihood of preterm births. RESULTS: Preterm births increased from 6.3 percent of live births in 1981 through 1983 to 6.8 percent in 1992 through 1994, a relative increase of 9 percent (95 percent confidence interval, 7 to 10 percent). Among singleton births, preterm births increased by 5 percent (95 percent confidence interval, 3 to 6 percent). Multiple births increased from 1.9 percent to 2.1 percent of all live births; the rates of preterm birth among live births resulting from multiple gestations increased by 25 percent (95 percent confidence interval, 21 to 28 percent). Adjustment for the determinants of the likelihood of preterm birth reduced the increase in the rate of preterm birth to 3 percent among all live births and 1 percent among singleton births. CONCLUSIONS: The recent increase in preterm births in Canada is largely attributable to changes in the frequency of multiple births, obstetrical intervention, and the use of ultrasound-based estimates of gestational age.

Birth Rate↗
PubMed1998

Distinct mechanism for antidepressant activity by blockade of central substance P receptors.

The localization of substance P in brain regions that coordinate stress responses and receive convergent monoaminergic innervation suggested that substance P antagonists might have psychotherapeutic properties. Like clinically used antidepressant and anxiolytic drugs, substance P antagonists suppressed isolation-induced vocalizations in guinea pigs. In a placebo-controlled trial in patients with moderate to severe major depression, robust antidepressant effects of the substance P antagonist MK-869 were consistently observed. In preclinical studies, substance P antagonists did not interact with monoamine systems in the manner seen with established antidepressant drugs. These findings suggest that substance P may play an important role in psychiatric disorders.

Adolescent↗
PubMed1998

Differences in late fetal death rates in association with determinants of small for gestational age fetuses: population based cohort study.

OBJECTIVE: To examine differences in late fetal death rates in association with determinants of small for gestational age fetuses. DESIGN: Population based cohort study. SUBJECTS: 1 026 249 pregnancies without congenital malformations. SETTING: Sweden 1983-92. MAIN OUTCOME MEASURE: Late fetal death rate. RESULTS: Depending on underlying determinants late fetal death rates were greatly increased in extremely small for gestational age fetuses (range 16 to 45 per 1000) compared with non-small for gestational age fetuses (1.4 to 4.6). In extremely small for gestational age fetuses late fetal death rates were increased from 31 per 1000 in mothers aged less than 35 years to 45 per 1000 in older mothers, and from 22 per 1000 in women <155 cm in height to 33 per 1000 in women >=175 cm tall. Late fetal death rates were also higher in extremely small for gestational age fetuses in singleton compared with twin pregnancies and in non-hypertensive pregnancies compared with pregnancies complicated by severe pre-eclampsia or other hypertensive disorders. Slightly higher late fetal death rates were observed in nulliparous compared with parous women and in non-smokers compared with smokers. CONCLUSIONS: Although the risk of late fetal death is greatly increased in fetuses that are extremely small for gestational age the risk is strongly modified by underlying determinants-for example, there is a lower risk of late fetal death in a small for gestational age fetus if the mother is of short stature, has a twin pregnancy, or has hypertension.

Adolescent↗
PubMed1998

Prepregnancy weight and the risk of adverse pregnancy outcomes.

BACKGROUND: Obesity before pregnancy is associated with an increased risk of several adverse outcomes of pregnancy. The risk profiles among lean, normal, or mildly overweight women are not, however, well established. METHODS: We studied the associations between prepregnancy body-mass index (defined as the weight in kilograms divided by the square of the height in meters) and the frequency of late fetal death, early neonatal death, preterm delivery, and delivery of a small-for-gestational-age infant in a population-based cohort of 167,750 women in Sweden in 1992 and 1993. The women were categorized as follows, according to body-mass index: lean, less than 20.0; normal, 20.0 through 24.9; overweight, 25.0 through 29.9; and obese, 30.0 or more. The estimates were adjusted for maternal age, parity, smoking, education, whether the mother was living with the father, and maternal height. RESULTS: Among nulliparous women, the odds ratios for late fetal death were increased among women with higher body-mass-index values as compared with lean women, as follows: normal women, 2.2 (95 percent confidence interval, 1.2 to 4.1); overweight women, 3.2 (95 percent confidence interval, 1.6 to 6.2); and obese women, 4.3 (95 percent confidence interval, 2.0 to 9.3). Among parous women, only obese women had a significant increase in the risk of late fetal death (odds ratio, 2.0; 95 percent confidence interval, 1.2 to 3.3). Among nulliparous women, the risk of very preterm delivery (at < or =32 weeks' gestation) was significantly increased among obese as compared with lean women (odds ratio, 1.6; 95 percent confidence interval, 1.1 to 2.3), whereas among parous women, the risk was highest among those who were lean. The risk of delivering a small-for-gestational-age infant decreased more with increasing body-mass index among parous than among nulliparous women. CONCLUSIONS: Higher maternal weight before pregnancy increases the risk of late fetal death, although it protects against the delivery of a small-for-gestational-age infant.

Adolescent↗
PubMed1998

Aminorex, dexfenfluramine, and primary pulmonary hypertension.

BACKGROUND: In the late 1960s, an epidemic of primary pulmonary hypertension (PPH) occurred in Europe shortly after the introduction of aminorex fumarate, a potent anorexigen. A recently published case-control study from Europe reported that use of other anorexigens (the most prevalent of which was dexfenfluramine) was also associated with an increased risk of PPH. This led to warnings of a repeat epidemic, especially after the introduction of dexfenfluramine on the North American market. OBJECTIVE: To compare the epidemiologic associations of PPH with aminorex and dexfenfluramine, both with respect to strength of association (estimate of relative risk) and public health impact (etiologic fraction) and thus to assess the potential for a new epidemic of PPH. METHODS: We constructed a "synthetic" case-control study for aminorex based on reported case series from Berne and Basel, Switzerland, and a random population sample from Hanover, Germany, and compared the results with those recently reported for dexfenfluramine. Control rates of exposure were used to estimate population exposure prevalences and, hence, etiologic fractions. RESULTS: The estimated odds ratio (and 95% confidence interval) for the association between PPH and any exposure to aminorex was 97.8 (78.9-121.3), with a corresponding etiologic fraction of 77%. The corresponding figures for dexfenfluramine were 3.7 (1.9-7.2) and 17%, respectively. CONCLUSION: The strong association between aminorex and PPH probably led to a 5-fold increase in PPH incidence, and thus a very noticeable epidemic. The association with dexfenfluramine would result in an increase in incidence of only 20%. Based on the available evidence, a repeat PPH epidemic seems unlikely.

Adult↗
PubMed1998

Maternal anthropometry-based screening and pregnancy outcome: a decision analysis.

OBJECTIVE: To assess the impact of screening and intervention based on maternal height, prepregnancy weight and weight during weeks 16-19 or 24-27 in reducing adverse pregnancy outcomes (IUGR, preterm birth and assisted delivery) in developing country settings. METHODS: Decision analysis based on a recent multicentre WHO collaborative study of maternal anthropometry and pregnancy outcomes and meta-analyses of controlled clinical trials of balanced energy/protein supplementation (for IUGR and preterm birth) and support from caregivers during labour (for assisted delivery). Subjects for the analysis comprised pregnant women from Cali, Colombia (1989, n = 4598); urban and rural Pune, India (1990, n = 4307); and urban and rural Myanmar (1981-82, n = 3542) followed until delivery. RESULTS: Seven to 45% of pregnant women had positive screens, with preventive fractions (PFs) ranging from 0.034 to 0.109 for IUGR, 0.027-0.082 for preterm birth and 0.011-0.105 for assisted delivery. Screening prevention ratios (SPRs = ratios of the number of women treated to the number of cases of adverse outcome prevented) are high in all three study settings for preterm birth and assisted delivery (range 22.8-115.7) and low in settings with a high prevalence of the adverse outcome and high specificity of the anthropometric measure (India for IUGR, range 7.0-8.0). Sensitivity analyses demonstrate a marked linear fall in PF and an exponential rise in the SPR as the relative risk associated with intervention increases (i.e. as the protective benefit of intervention decreases) from 0.60 to 0.95. CONCLUSIONS: A maternal anthropometry-based 'risk approach' is unlikely to result in a major reduction in adverse pregnancy outcomes in developing country settings. For risk-free and inexpensive interventions (e.g. caregiver support during labour), a better strategy would be to forego screening and instead treat all pregnant women.

Anthropometry↗
PubMed1998

A placebo-controlled crossover study of rizatriptan in the treatment of multiple migraine attacks. Rizatriptan Multiple Attack Study Group.

OBJECTIVE: To examine the safety and efficacy of rizatriptan 10 mg PO in the treatment of multiple migraine attacks. BACKGROUND: Rizatriptan is a potent and rapidly absorbed 5-HT1B/1D receptor agonist. Efficacy and general safety have been examined in controlled trials treating single migraine attacks. In the current placebo-controlled study, we report constancy of safety and efficacy of rizatriptan for patients treating four discrete migraine attacks. METHODS: Patients with moderate or severe migraine (n = 473) were randomized to one of five sequence groups, in which each patient was to treat four migraine attacks. Patients in four groups received rizatriptan 10 mg for three of four attacks and placebo for the remaining attack. Patients in the fifth group received rizatriptan 10 mg for four attacks. Headache severity, functional disability, and migraine symptoms were measured immediately before dosing and at 0.5, 1, 1.5, 2, 3, and 4 hours postdose. RESULTS: After the first attack, response rates were 77% for rizatriptan and 37% for placebo (p < 0.001). Similar efficacy of rizatriptan, ranging from a 75 to 80% response, was observed in each of the subsequent attacks with no evidence of tolerance to therapeutic effects. Most patients (93%) responded to rizatriptan 10 mg during the first or second attack. Adverse experiences were generally mild and transient, the most common being dizziness and somnolence. Incidence of adverse experiences per attack decreased after the first attack. CONCLUSIONS: Rizatriptan 10 mg PO is efficacious and generally well tolerated in acute migraine. Its efficacy is maintained throughout the treatment of multiple, discrete migraine attacks.

Administration, Oral↗
PubMed1998

The decline in Rh hemolytic disease: should Rh prophylaxis get all the credit?

OBJECTIVES: This study sought to quantify the magnitude of Rh disease reduction occurring secondary to Rh prophylaxis and other determinants. METHODS: Outcomes considered included maternal Rh sensitization, neonatal Rh disease, and perinatal deaths from Rh disease. Analysis was based on Poisson regression modeling of ecological data from Manitoba, Canada, and conditional probability modeling. RESULTS: The ecological analysis showed that changes in birth order and Rh prophylaxis resulted in 24% (95% confidence interval [CI] = 1% 42%) and 69% (95% CI = 61%, 76%) decreases, respectively, in Rh sensitizations (D and non-D) in Manitoba between 1963 and 1988. Rh prophylaxis and nonprogram factors were responsible for 83% (95% CI = 44%, 95%) and 78% (95% CI = 42%, 91%), respectively, of the reduction in perinatal deaths from Rh disease. Similar results were obtained with conditional probability modeling, which also provided estimates for the effects of changes in abortion rates and racial composition. CONCLUSIONS: In addition to Rh prophylaxis, changes in other determinants were responsible for an important fraction of the decline in Rh disease. These results provide a historical perspective on the conquest of Rh disease and also have important implications for public health policy, particularly in developing countries.

Erythroblastosis, Fetal↗
PubMed1998

Socioeconomic determinants of intrauterine growth retardation.

This paper reviews the evidence bearing on socioeconomic determinants of intrauterine growth retardation (IUGR). The primary focus is on those factors with a quantitatively important impact from a public health perspective, as indicated by their large etiologic fraction (population attributable risk). In developed countries in which a sizeable proportion of women smoke during pregnancy, cigarette smoking is associated with the largest etiologic fraction (by far), followed by low gestational weight gain (primarily due to low energy intake) and low prepregnancy body mass index (BMI). In developing countries where undernutrition is prevalent and pregnant women do not smoke, low maternal weight gain and BMI assume even greater importance, as does short maternal stature. A major section of the paper concerns the large within-country socioeconomic disparities in IUGR and the possible mechanisms underlying these disparities. In developed countries, differences in cigarette smoking explain a large part of the disparity; low weight gain and short stature may also be important mediators in some settings. Future etiologic studies should assess a wide scope of potential determinants and will require large sample sizes to control for their mutually confounding effects.

Body Mass Index↗
PubMed1997

Recent trends in infant mortality rates and proportions of low-birth-weight live births in Canada.

OBJECTIVE: To identify spatial patterns of changes in infant mortality rates and proportions of low-birth-weight live births observed in 1994. SETTING: Canada. SUBJECTS: Live births and infant deaths in Canada between 1987 and 1994. Data for Newfoundland were unavailable for 1987 through 1990. OUTCOME MEASURES: Annual infant mortality rates (crude and after excluding live newborns weighing less than 500 g); proportion of live births by low-birth-weight category (500-2499 g). RESULTS: Nova Scotia, New Brunswick, Quebec and Manitoba had lower crude and adjusted infant mortality rates in 1994 than in 1993. Newfoundland, Saskatchewan, Alberta and British Columbia had higher rates in 1994 than in 1993. The crude rate in Ontario was lower, and the adjusted rate higher, in 1994 than in 1993. A downward trend in the proportion of low-birth-weight live births was observed in Quebec (chi(2) for trend = 29.2, p < 0.01). Conversely, an upward trend was observed in Ontario (chi(2) for trend = 241.3, p < 0.01). However, the increase may have been due to data errors, especially in 1993 and 1994, involving truncation of ounces in 2 digits to 1 digit (e.g., 5 pounds 10 ounces became 5 pounds 1 ounce). CONCLUSIONS: Although the marginal increases in infant mortality observed in several provinces could be the result of random variation, future trends should be closely monitored. The proportion of low-birth-weight live births in Canada (excluding Ontario) appears to be stable, with Quebec showing significant reductions. The errors in data for Ontario need to be corrected before trends can be estimated for that province and for Canada as a whole.

Birth Weight↗
PubMed1997

Sudden infant death syndrome and smoking in the United States and Sweden.

The association between sudden infant death syndrome (SIDS) and maternal smoking was compared between the United States and Sweden-two countries with different health care and social support programs and degrees of sociocultural heterogeneity. For 1990-1991 among the five US race/ethnic groups studied, SIDS rates ranged from a high of 3.0 infant deaths per 1,000 live births for American Indians to a low of 0.8 for Hispanics and Asian and Pacific Islanders. The SIDS rate for Sweden (using 1983-1992 data) was 0.9. The strong association between maternal smoking and SIDS persisted after controlling for maternal age and live birth order. Adjusted odds ratios ranged from 1.6 to 2.5 for mothers who smoked 1-9 cigarettes per day during pregnancy (compared with nonsmokers) and from 2.3 to 3.8 for mothers who smoked 10 or more cigarettes per day during pregnancy. Although birth weight had a strong independent effect on SIDS, the addition of birth weight to the models lowered the odds ratios for maternal smoking only slightly, suggesting that the effect of smoking on SIDS is not mediated through birth weight. SIDS rates increased with the amount smoked for all US race/ethnic groups and for Sweden. Smoking is one of the most important preventable risk factors for SIDS, and smoking prevention/intervention programs have the potential to substantially lower SIDS rates in the United States and Sweden and presumably elsewhere as well.

Adolescent↗
PubMed1997

The effects of a selective D4 dopamine receptor antagonist (L-745,870) in acutely psychotic inpatients with schizophrenia. D4 Dopamine Antagonist Group.

BACKGROUND: Based mainly on the selective antagonism of clozapine at D4 compared with D2 dopamine receptors, hopes have run high that a selective D4 dopamine receptor antagonist might improve the pharmacological treatment of patients with schizophrenia. We report, to our knowledge, the first multicenter study of the antipsychotic potential of a highly specific D4 dopamine receptor antagonist (ie, L-745,870) in patients with acute schizophrenia. METHODS: Thirty-eight acutely psychotic and neuroleptic responsive (by history) newly admitted inpatients with schizophrenia were randomized to 4 weeks of double-blind treatment (2:1) with either L-745,870 (n = 26), 15 mg/d, or placebo (n = 12) after a 3- to 5-day placebo run-in period. RESULTS: Overall, a greater percentage of patients receiving L-745,870 compared with patients receiving placebo discontinued the study for insufficient therapeutic response (32% vs 16%). At the end of 4 weeks by last observation carried forward analysis, the mean change from baseline to week 4 on the total Brief Psychiatric Rating Scale favored placebo (i.e., -8 points [-15% change from baseline] vs -1 point [-2% change from baseline] for placebo vs L-745,870, P = .09). Similar differences in favor of placebo in changes from baseline mean scores were observed for the not carried forward analysis on the total Brief Psychiatric Rating Scale (P < .03), for not carried forward and last observation carried forward analyses on the sum of selected positive symptom items of the Brief Psychiatric Rating Scale, and for the Clinical Global Impression analysis (P = .03, last observation carried forward). A greater percentage of patients receiving L-745,870 had scores indicative of some level of worsening (compared with baseline) on the total Brief Psychiatric Rating Scale and the Clinical Global Impressions' Severity of Illness Scale as well as positive symptoms compared with those receiving placebo. CONCLUSION: The selective D4 dopamine receptor antagonist L-745,870 was ineffective as an antipsychotic for the treatment of neuroleptic responsive inpatients with acute schizophrenia.

Acute Disease↗
PubMed1997

A randomized trial of a program of early postpartum discharge with nurse visitation.

OBJECTIVE: Our purpose was to compare an early postpartum discharge program versus standard postpartum care. STUDY DESIGN: A randomized controlled trial in a 637-bed university hospital included 175 healthy women recruited at 32 to 38 weeks gestation from physicians' offices and sonograms. Experimental intervention consisted of discharge 6 to 36 hours post partum with nursing care available by telephone or at home at 34 to 38 weeks' gestation and at < or = 48 hours and at 3, 5, and 10 days post partum. The control included a postpartum stay of 48 to 72 hours and standard follow-up. RESULTS: At 1 month no significant differences were seen in perceived maternal competence (Experimental-Control = 4.3 points [95% confidence interval-7.7 to 16.3]), infant weight gain (1.2 gm/ day [-2.8 to 5.2]); identification of significant neonatal hyperbilirubinemia (rate ratio 0.50 [0.10 to 2.51]), infant utilization of health services (rate ratio 0.88 [0.45 to 1.73]), or predominant breast-feeding (adjusted odds ratio 1.25 [0.88 to 1.75]). Program participants did have significantly less frequent infant bilirubin testing (rate ratio 0.39 [0.17 to 0.94]). The program also enhanced perceived maternal competence in recent immigrants (26.9 points [2.7 to 51.5]). CONCLUSIONS: Early postpartum discharge coupled with prenatal, postnatal, and home contacts leads to no apparent disadvantage and may yield benefits for some mothers and infants.

Community Health Nursing↗