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Biomedical subjects

H Kraemer

Publications and source records attributed to H Kraemer.

35 records · Page 2Linked to original sources
PubMed1981

Disorders of excessive daytime somnolence: polygraphic and clinical data for 100 patients.

A consecutive series of 100 sleep apnea free patients with the complaint of excessive daytime somnolence (EDS) were evaluated; data from medical histories, physical examination, personality inventories, and polysomnography [nocturnal polysomnography (NPSG) and daytime multiple sleep latency testing (MSLT)] were tabulated. Significant differences were found between narcoleptic and non-narcoleptic patients in a number of parameters, including EDS severity, mean sleep latency on MSLT, sleep latency on NPSG, latency to REM sleep at night, number of REM sleep at night, number of REM sleep segments throughout the night, the total number of nocturnal myoclonic jerks (as well as the number occurring per hour of NREM and REM sleep), and the number of arousals and wake periods preceded by a myoclonic jerk. Significant differences in sleep latency during MSLT and NPSG testing were found between different EDS diagnostic groups of non-narcoleptic patients. The majority of patients in the MSLT group with long sleep latencies were in the diagnostic groups of EDS associated with psychophysiological and/or psychiatric problems or with drug abuse; patients with a diagnosis of idiopathic central nervous system hypersomnia or EDS associated with disturbed nocturnal sleep formed the majority of the MSLT group with short sleep latencies. The non-narcoleptic patients in a MSLT group with short sleep latencies had significantly shorter sleep latencies at night, more sleep cycles, higher sleep efficiency, and earlier REM sleep than patients with long sleep latencies.

Adolescent↗
PubMed1981

Comparison of oral prostaglandin E2 and intravenous oxytocin for induction of labour.

153 oral prostaglandin E2 (PGE2) inductions of labour were compared with 172 inductions with oxytocin. Details of these inductions are presented. After review of the data we assumed that induction of labour with oral PGE2 is less hazardous to mother or infant than with oxytocin. The similarity between the contractions of spontaneous labour and those labours produced by PGE2 is represented by the caesarean section rate in cases of effective induction. The operative delivery rate in the oxytocin-treated group was significantly higher. The need for close observation of the progress of labour during PGE2 inductions is emphasized.

Administration, Oral↗
PubMed1980

A new method for evaluating antiarrhythmic drug efficacy.

To develop standards for distinguishing antiarrhythmic drug effect from spontaneous variability of premature ventricular complexes (PVCs), 21 males (mean age 56 +/- 8 years) with chronic ischemic heart disease and PVCs underwent symptom-limited treadmill exercise testing and 24-hour ambulatory monitoring before and after 2 weeks of placebo medication. Linear regression analysis was used to describe the relationship between baseline and placebo PVC frequency for various indexes of ventricular ectopic activity and to establish 95% and 99% one-tailed confidence intervals for this relationship within the group of 21 patients. The lower limit of baseline PVC frequency for which the procedure could distinguish a placebo from a true drug response, termed the "sensitivity threshold," was an average frequency of 2.2 PVCs/hour for ambulatory electrocardiographic monitoring and 1.2 PVCs/min for treadmill exercise testing. All patients exceeded the sensitivity threshold on baseline ambulatory ECGs, but only 38% of patients did so on baseline treadmill exercise tests. To establish antiarrhythmic efficacy with 95% confidence, the minimal percent reduction of PVCs between baseline and placebo visits was 68% for treadmill exercise testing and 65% for ambulatory electrocardiography. Although these standards were developed in patients with chronic ischemic heart disease, the model can be used to establish antiarrhythmic drug efficacy in any patient group.

Ambulatory Care↗
PubMed1980

CSF monoamine metabolites in depression and schizophrenia.

The authors report cerebrospinal fluid (CSF) concentrations of five monoamine metabolites before and after probenecid administration in normal subjects and patients with depression and schizophrenia. No differences were found in baseline metabolite concentrations among the three groups. CSF metabolite and CSF probenecid concentrations were significantly correlated in depressed patients for all metabolites, and there was decreased postprobenecid accumulation of homovanillic acid in the CSF of depressed patients compared with schizophrenic patients and with normal subjects. The authors propose a method for correcting for probenecid concentrations. Data from normal subjects should be of value for other investigators using the probenecid technique.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1979

Reproducibility of exercise-induced ventricular arrhythmia after myocardial infarction.

To evaluate the reproducibility of exercise-induced ventricular arrhythmia, 155 men with a mean age of 53 +/- 8 years underwent serial exercise testing 3 to 52 weeks after myocardial infarction. The reproducibility of categorical test responses, that is, the presence or absence of ventricular arrhythmia, was evaluated with the kappa coefficient, which considers negative as well as possible test responses and expresses reproducibility above the chance level. Reproducibility was highest at an intertest interval of 1 to 5 days and was not enhanced by further categorizing premature ventricular complexes as simple or complex based on their frequency or configuration. Continuous response measures such as frequency of premature ventricular complexes yielded higher reproducibility than categorical responses. Continuous response measures appear preferable to categorical responses for evaluating the clinical significance and response to antiarrhythmic therapy of ventricular arrhythmias.

Arrhythmias, Cardiac↗
PubMed1979

The prognostic significance of serial exercise testing after myocardial infarction.

Serial treadmill exercise testing (mean 5.5 tests/patient) was used to evaluate the prognosis of 200 males (mean age 53 years) without clinical heart failure or unstable angina pectoris 3 weeks after acute myocardial infarction (MI). Exercise-induced ischemic ST-segment depression greater than or equal to 0.2 mV 3 weeks after MI was significantly more prevalent in patients with subsequent cardiac arrest (100%) or coronary artery bypass graft surgery (64%) than in patients without subsequent events within 2 years of infarction (35%) (p less than 0.05). Exercise-induced ventricular arrhythmia on multiple tests 5-52 weeks after MI was more prevalent in patients with recurrent myocardial infarction (90%) than in patients without subsequent events (47%) (p less than 0.001). By contrast, exercise-induced ventricular arrhythmia on a single test at 3 weeks was a less powerful predictor of subsequent cardiac events. Exercise-induced ischemia 3 weeks after MI predicted early fatal events, while ventricular arrhythmia on serial testing predicted later nonfatal events.

Adult↗
PubMed1979

Concentrations of sex hormones in umbilical-cord blood: their relation to sex and birth order of infants.

In 3 groups of human newborns, 5 sex hormones were assayed from samples of umbilical-cord blood, and concentrations were analyzed by the sex and birth order of the infants. The 5 hormones assayed were testosterone, androstenedione, estrone, estradiol, and progesterone. Concentrations of testosterone were significantly greater in males than females. The other 4 hormones did not differ significantly by sex. In both sexes, firstborns had significantly more progesterone and estrogens, with progesterone showing the largest birth-order effects. Among male infants, firstborns had higher concentrations of testosterone. The higher concentrations of progesterone in firstborns of both sexes, and of testosterone in firstborn boys, were found not to be due to length of labor, birth weight, or maternal age. However, they were a function of temporal spacing of childbirths. Later borns who were closely spaced in relation to their next-older siblings had lower concentrations of hormones. The effect of temporal separation was greater on male than female infants for each of the 5 hormones studied. The results are discussed in terms of the possible effects of hormone "depletion" on the psychological development of closely spaced later borns.

Androstenedione↗
PubMed1975

REM phase deprivation and schizophrenia II.

Nine schizophrenic patients with active symptomatology were compared with seven patient controls in their response to two nights of rapid eye movement (REM) sleep deprivation. The control subjects demonstrate "normal" increases in total REM and percentage REM time increase on recovery nights compared to base line nights. The schizophrenic subjects differ substantially from the control subjects in both these measurements and show no perceptible change from base line nights on recovery nights. The effects of medication, anxiety, sleep loss, ceiling effects, and intensity change were not considered adequate to account for the above results. However, many questions, such as the specificity of this rebound failure to the schizophrenic patients and the possibility of a sleep disturbance factor operating independently of psychiatric diagnosis, remain to be answered.

Adult↗