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PubMedDate not supplied

[Chronic pathologies and pharmaceutical expenditure in persons over the age of 65].

OBJECTIVE: For purposes of the present study of people over 65 attending a particular Health Centre, we aimed to discover and inter-relate their morbidity due to chronic illnesses, their frequency of attendance, and the total average outlay of drugs on them. DESIGN: Descriptive crossover study. Information on the clinical histories was gathered over a one-year period (July 1990 to June '91). SITE. Within the Primary Care framework: at the Vite Health Centre in Santiago de Compostela. PATIENTS OR OTHERS PARTICIPANTS: The population aged 65 or over and with medical records in the said centre. A representative sample of this population (n = 240), obtained by systematic sampling, was worked with. MAIN RESULTS: The sample's average age was 73.6 +/- 6.7 years. Arterial Hypertension (AHT) was the most common chronic illness. AHT, LCFA/Asthma, Hyperlipemia and digestive pathology showed significant differences between men and women. The average number of medical consultations per person per year was 11.5 +/- 0.82, with no significant differences as to sex and age. The average outlay per person per year was 27,610 pesetas +/- 38,688, with an average cost per consultation of 2,750 pesetas +/- 5,158.7. The chronic illnesses that produced a higher average total cost were heart diseases. Significant differences were shown between the number of chronic illnesses and the average total cost. CONCLUSIONS: The presence, number and nature of chronic illnesses are the factors affecting higher outlay in medication.

Aged↗
PubMed1993

An index marker map of chromosome 9 provides strong evidence for positive interference.

An index marker map of chromosome 9 has been constructed using the Centre d'Etude du Polymorphisme Humain reference pedigrees. The map comprises 26 markers, with a maximum intermarker interval of 13.1 cM and only two intervals > 10 cM. Placement of all but one marker into the map was achieved with > 10,000:1 odds. The sex-equal length is 151 cM, with male length of 121 cM and female length of 185 cM. The map extends to within 2%-3% of physical length at the telomeres, and its coverage therefore is expected to be within 20-30 cM of full map length. The markers are all of the GT/CA repeat type and have average heterozygosity .77, with a range of .60-.89. The map shows both marked contraction of genetic distance relative to physical distance in the pericentromeric region and expansion in the telomeric regions. Genotypic data were carefully examined for errors by using the crossover routine of the program DATAMAN. Five new mutations were observed among 17,316 meiotic events examined. There were two double-crossover events occurring within an interval of 0-10 cM, and another eight were observed within an interval of 10-20 cM. Many of these could be due to additional mutational events in which one parental allele converted to the other by either gene conversion or random strand slippage. When there was no correction for these possible mutational events, the number of crossovers displayed by the maternal and paternal chromosomes was significantly different (P < .001) from that predicted by the Poisson distribution, which would be expected in the absence of interference. In addition, the observed crossover distribution for paternally derived chromosomes was similar to that predicted from cytogenetic chiasma frequency observations. In all, the data strongly support the occurrence of strong positive interference on human chromosome 9 and suggest that flanking markers at an interval of < or = 20 cM are generally sufficient for disease gene inheritance predictions in presymptomatic genetic counseling by linkage analysis.

Base Sequence↗
PubMed1996

Dietary assessment in epidemiology: comparison on food frequency and a diet history questionnaire with a 7-day food record.

The validity of two types of diet assessment methods, a self-administered food frequency questionnaire and and interviewer-administered detailed diet history, was assessed relative to a 7-day food record on a population- based sample of 95 men and 108 women in Toronto, Canada, between May 1989 and July 1990. Each study subject completed both questionnaire methods, a food frequency questionnaire and an interviewer-administered diet history, as well as a 7-day food record in a crossover design. Data were analyzed for both unadjusted and energy-adjusted nutrients to estimate Pearson's and intraclass correlations and agreement within the categories. Mean values for the intake of most nutrients assessed by the two questionnaire methods were similar. Average, energy-adjusted Pearson's correlation coefficients for men between a food frequency questionnaire and a 7-day food record were 0.55 for macronutrients and 0.48 for micronutrients compared with 0.47 for macro- and 0.48 for micronutrients between an interviewer-administered diet history and a 7-day food record. For women, they were 0.48 for macro- and 0.54 for micronutrients between a food frequency questionnaire and a 7-day food record and 0.46 and 0.49, respectively, between an interviewer-administered diet history and a 7-day food record. The energy-adjusted Pearson correlations were generally higher than were the energy-unadjusted Pearson correlations and the intraclass correlations. The present study suggests that a food frequency questionnaire is comparable with an interviewer-administered diet history as a predictor of nutrients as estimated form a 7-day food record.

Adult↗
PubMed1998

High level of unequal meiotic crossovers at the origin of the 22q11. 2 and 7q11.23 deletions.

Interstitial chromosomal deletions at 22q11.2 and 7q11.23 are detected in the vast majority of patients affected by CATCH 22 syndromes and the Williams-Beuren syndrome, respectively. In a group of 15 Williams-Beuren patients, we have shown previously that a large number of 7q11.23 deletions occur in association with an interchromosomal rearrangement, indicative of an unequal crossing-over event between the two homologous chromosomes 7. In this study, we show that a similar mechanism also underlies the formation of the 22q11.2 deletions associated with CATCH 22. In eight out of 10 families with a proband affected by CATCH 22, we were able to show that a meiotic recombination had occurred at the critical deleted region based on segregation analysis of grandparental haplotypes. The incidences of crossovers observed between the closest informative markers, proximal and distal to the deletion, were compared with the expected recombination frequencies between the markers. A significant number of recombination events occur at the breakpoint of deletions in CATCH 22 patients (P = 2.99x10(-7)). The segregation analysis of haplotypes in three-generation families was also performed on an extended number of Williams-Beuren cases (22 cases in all). The statistically significant occurrence of meiotic crossovers (P = 4.45x10(-9)) further supports the previous findings. Thus, unequal meiotic crossover events appear to play a relevant role in the formation of the two interstitial deletions. The recurrence risk for healthy parents in cases where such meiotic recombinations can be demonstrated is probably negligible. Such a finding is in agreement with the predominantly sporadic occurrence of the 22q11.2 and 7q11. 23 deletions. No parent-of-origin bias was observed in the two groups of patients with regard to the origin of the deletion and to the occurrence of inter- versus intrachromosomal rearrangements.

Adolescent↗
PubMed2000

Oxygen supplementation and cardiac-autonomic modulation in COPD.

STUDY OBJECTIVES: Patients with COPD have an increased sympathetic modulation and reduced baroreflex sensitivity (BRS). Therefore, we studied the effects of breathing 31% supplemental oxygen (SuppO(2)) on autonomic modulation in a group of COPD patients. DESIGN: We measured autonomic modulation before and during the administration of SuppO(2) on 51 patients with COPD using time-frequency analysis of R-R intervals and BP before and after intervention. This was done via a counterbalanced crossover design. The BRS index was determined using the sequence method. RESULTS: Significant differences were seen in oxygen saturation levels following breathing with SuppO(2) ([mean +/- SD] 96.4+/-1.5%) when compared to those seen after breathing with compressed air (CA) (92.8+/-2.9%; p<0.0001). Significant increases were seen in the natural log-transformed high-frequency modulation (HFln) (SuppO(2), 10.8+/-1.3 natural logarithm [ln] ms(2)/Hz; CA, 10.6+/-1.3 ln ms(2)/Hz; p<0.028) and BRS (SuppO(2), 3.3+/-2.2 ms/mm Hg; CA, 2.8+/-1.8 ms/mm Hg) following the supplemental oxygen treatment (p<0.015). The low-frequency/high-frequency ratio of heart rate variability revealed significant differences between the two treatments (SuppO(2), 2.7 +/-1.2; CA, 3.1+/-1.3; p<0.008). The analysis of BP variability data revealed significant decreases in the HFln (CA, 6.9+/-1.0 mm Hg(2)/Hz; SuppO(2), 6.5+/-1.2 mm Hg(2)/Hz; p<0.0001). Hemodynamic data also revealed a decrease in mean heart rate after breathing SuppO(2) compared with that after breathing CA (CA, 87.3+/-13.3 beats/min; SuppO(2), 85.0+/-12.4 beats/min; p<0.0004). The arterial pulse pressure significantly decreased when breathing SuppO(2) compared with that when breathing CA (CA, 57.2+/-13.5 mm Hg; SuppO(2), 53.3+/-13.0 mm Hg; p<0.0023). CONCLUSION: Oxygen supplementation in COPD patients significantly and favorably alters autonomic modulation.

Autonomic Nervous System↗
PubMed2005

Beneficial metabolic effects of regular meal frequency on dietary thermogenesis, insulin sensitivity, and fasting lipid profiles in healthy obese women.

BACKGROUND: Although a regular meal pattern is recommended for obese people, its effects on energy metabolism have not been examined. OBJECTIVE: We investigated whether a regular meal frequency affects energy intake (EI), energy expenditure, or circulating insulin, glucose, and lipid concentrations in healthy obese women. DESIGN: Ten women [x +/- SD body mass index (in kg/m(2)): 37.1 +/- 4.8] participated in a randomized crossover trial. In phase 1 (14 d), the subjects consumed their normal diet on 6 occasions/d (regular meal pattern) or followed a variable meal frequency (3-9 meals/d, irregular meal pattern). In phase 2 (14 d), the subjects followed the alternative pattern. At the start and end of each phase, a test meal was fed, and blood glucose, lipid, and insulin concentrations were determined before and for 3 h after (glucose and insulin only) the test meal. Subjects recorded their food intake on 3 d during each phase. The thermogenic response to the test meal was ascertained by indirect calorimetry. RESULTS: Regular eating was associated with lower EI (P < 0.01), greater postprandial thermogenesis (P < 0.01), and lower fasting total (4.16 compared with 4.30 mmol/L; P < 0.01) and LDL (2.46 compared with 2.60 mmol/L; P < 0.02) cholesterol. Fasting glucose and insulin values were not affected by meal pattern, but peak insulin concentrations and area under the curve of insulin responses to the test meal were lower after the regular than after the irregular meal pattern (P < 0.01 and 0.02, respectively). CONCLUSION: Regular eating has beneficial effects on fasting lipid and postprandial insulin profiles and thermogenesis.

Adult↗
PubMed1999

Comment on "Merging of the alpha and beta relaxations in polybutadiene: a neutron spin echo and dielectric study".

The evaluation method of dielectric data based on a Williams product ansatz [A. Arbe, D. Richter, J. Colmenero, and B. Farago, Phys. Rev. E 54, 3853 (1996)] is not suited to the crossover region of the dynamic glass transition. This method is insensitive to the shape, position, or even existence of at least one of the relaxation functions if, in the extrapolation from below to above the crossover region, the two processes cross or approach one another. Since a crossover region without any particular change in the relaxation mechanism of these processes can in fact be adjusted by this method, better dielectric data for polybutadiene in the gigahertz frequency region are needed to determine whether or not there are peculiarities in the dielectric function. It would be an odd assumption that the many particularities in the crossover region in other instances are not reflected in the dielectric response.

Letter↗
PubMed2002

Patterns of meiotic recombination in human fetal oocytes.

Abnormal patterns of meiotic recombination (i.e., crossing-over) are believed to increase the risk of chromosome nondisjunction in human oocytes. To date, information on recombination has been obtained using indirect, genetic methods. Here we use an immunocytological approach, based on detection of foci of a DNA mismatch-repair protein, MLH1, on synaptonemal complexes at prophase I of meiosis, to provide the first direct estimate of the frequency of meiotic recombination in human oocytes. At pachytene, the stage of maximum homologous chromosome pairing, we found a mean of 70.3 foci (i.e., crossovers) per oocyte, with considerable intercell variability (range 48-102 foci). This mean equates to a genetic-map length of 3,515 cM. The numbers and positions of foci were determined for chromosomes 21, 18, 13, and X. These chromosomes yielded means of 1.23 foci (61.5 cM), 2.36 foci (118 cM), 2.5 foci (125 cM), and 3.22 foci (161 cM), respectively. The foci were almost invariably located interstitially and were only occasionally located close to chromosome ends. These data confirm the large difference, in recombination frequency, between human oocytes and spermatocytes and demonstrate a clear intersex variation in distribution of crossovers. In a few cells, chromosomes 21 and 18 did not have any foci (i.e., were presumptively noncrossover); however, configurations that lacked foci were not observed for chromosomes 13 and X. For the latter two chromosome pairs, the only instances of absence of foci were observed in abnormal cells that showed chromosome-pairing errors affecting these chromosomes. We speculate that these abnormal fetal oocytes may be the source of the nonrecombinant chromosomes 13 and X suggested, by genetic studies, to be associated with maternally derived chromosome nondisjunction.

Adaptor Proteins, Signal Transducing↗
PubMed1990

Frequency and distribution of chiasmata in Syrian hamster spermatocytes studied by the BrdU antibody technique.

The frequency and distribution of chiasmata and the nature of terminal "associations" was re-examined in Syrian hamster spermatocytes using the 5-bromo-2'-deoxyuridine (BrdU) antibody technique (BAT) for differential chromatid labelling. Differential chromatid substitution was achieved by BrdU incorporation at the penultimate pre-meiotic S-phase followed by one of three different staining protocols: (i) fluorescence plus Giemsa (FPG), (ii) acridine orange staining or (iii) BAT. For analysis of chiasmata frequency and localization in the diplotene/diakinesis stages the resolution of FPG and acridine orange staining was comparable to that of BAT. In metaphase II chromosomes BAT was more informative than FPG and acridine orange staining and revealed small, terminal crossover exchanges. This finding proves that many terminal associations of meiotic chromosomes actually represent chiasmata at the end of the first meiotic division. Some crossover exchanges were localized in the constitutive heterochromatin of autosomes. Using BAT we also detected crossover exchanges in close vicinity to each other. This observation is reminiscent of the fact that crossing over interference means a reduction in frequency and does not imply total inhibition.

Animals↗
PubMed2004

A randomized, double-blind, crossover study of the use of transcutaneous spinal electroanalgesia in patients with pain from chronic critical limb ischemia.

Transcutaneous spinal electroanalgesia (TSE) uses two electrodes placed over the skin of the dorsal spine to deliver pulses of short wavelength, high frequency, and relatively high voltage to the spinal cord without causing paresthesia. TSE has been used to treat pain and may improve limb blood flow. This randomized, double-blind, crossover study assessed the effect of TSE on microcirculation, pain, and activity in 8 patients (3 men, 5 women, median age 66.5 years, range 62-76 years) with chronic critical limb ischemia (CLI). After a one-week baseline period, patients used an active or inactive TSE machine for one hour daily for one week. Following a week of no stimulation, patients repeated the week of treatment with an identical matched machine. Daily use of TSE for one week did not improve microcirculatory perfusion (transcutaneous oxygenation), pain (verbal rating scale, McGill Pain Questionnaire), physical function (Functional Limitations Profile), mood (Beck Depression Inventory, Beck Anxiety Inventory), or sleep. There was no patient preference for the active TSE machines. This study showed that TSE administered daily for one week did not improve microcirculation, pain, or activity in patients with chronic CLI.

Aged↗
PubMed1993

Physical exertion as a trigger of acute myocardial infarction. Triggers and Mechanisms of Myocardial Infarction Study Group.

BACKGROUND: It is controversial whether the onset of myocardial infarction occurs randomly or is precipitated by identifiable stimuli. Previous studies have suggested a higher risk of cardiac events in association with exertion. METHODS: Consecutive patients with acute myocardial infarction were identified by recording all admissions to our hospital in Berlin and by monitoring a general population of 330,000 residents in Augsburg, Germany. Information on the circumstances of each infarction was obtained by means of standardized interviews. The data analysis included a comparison of patients with matched controls and a case-crossover comparison (one in which each patient serves as his or her own control) of the patient's usual frequency of exertion with the last episode of exertion before the onset of myocardial infarction. RESULTS: From January 1989 through December 1991, 1194 patients (74 percent of whom were men; mean age [+/- SD], 61 +/- 9 years) completed the interview 13 +/- 6 days after infarction. We found that 7.1 percent of the case patients had engaged in physical exertion (> or = 6 metabolic equivalents) at the onset of infarction, as compared with 3.9 percent of the controls at the onset of the control event. For the patients as compared with the matched controls, the adjusted relative risk of having engaged in strenuous physical activity at the onset of infarction or the control event was 2.1 (95 percent confidence interval, 1.1 to 3.6). The case-crossover comparison yielded a similar relative risk of 2.1 (95 percent confidence interval, 1.6 to 3.1) for having engaged in strenuous physical activity within one hour before myocardial infarction. Patients whose frequency of regular exercise was less than four and four or more times per week had relative risks of 6.9 and 1.3, respectively (P < 0.01). CONCLUSIONS: A period of strenuous physical activity is associated with a temporary increase in the risk of having a myocardial infarction, particularly among patients who exercise infrequently. These findings should aid in the identification of the triggering mechanisms for myocardial infarction and improve prevention of this common and serious disorder.

Aged↗
PubMed1996

Effects of an external nasal dilator on sleep and breathing patterns in newborn infants with and without congestion.

BACKGROUND: We recently demonstrated that the use of an external nasal dilator reduced subjective snoring levels and improved sleep quality. Our study polysomnographically evaluated the effects of this device on the frequency of obstructive airway events during sleep in infants with and without congestion. METHODS: We used a crossover study to monitor 20 infants between the ages of 2 and 4 months (15 infants without congestion and 5 with congestion). Monitoring was conducted during two daytime sleep sessions in a crossover study in which infants slept with or without a cutdown version of an external nasal dilator (Breathe Right Nasal Strips, CNS, Inc., Bloomington, Minn.) in the first session with crossover to the other condition in the second session. A respiratory disturbance index consisting of apneas (pauses in respiration of at least 8 seconds) or hypopneas (decreased airflow resulting in oxygen desaturation of at least 3%) was determined. RESULTS: Babies without congestion showed a greater than 50% reduction in respiratory disturbance index from 3.2 +/- 2.8 to 1.2 +/- 1.2 events per hour (p < 0.005). Congested infants showed a decrease from 6.9 +/- 2.9 to 1.5 +/- 1.6 events per hour (p < 0.05). Babies with the greatest number of events showed the greatest improvement. CONCLUSION: The use of an external nasal dilator reduces the frequency of obstructive respiratory events in infants.

Cross-Over Studies↗
PubMed1993

Heart rate variability and circulating catecholamine concentrations during steady state exercise in healthy volunteers.

OBJECTIVES: To assess whether exercise induced suppression of heart rate variability in the low frequency domain (0.06-0.15 Hz) is related to the increase in circulating catecholamine concentrations. DESIGN: Randomised crossover trial of three exercise tests characterised by different workloads. Pharmacological simulation of exercise-induced changes in vagal and sympathetic activity. PARTICIPANTS: Six healthy men with a mean age of 31.2 (SD 3.0) years. INTERVENTIONS: Three different workloads of steady state cycling ergometry: control state without cycling, cycling at a target heart rate of 100 beats/min, and cycling at a target heart rate of 150 beats/min. Intravenous infusion of atropine (target heart rate 100 beats/min) followed by the additional infusion of adrenaline and noradrenaline. MAIN OUTCOME MEASURES: Fast Fourier analysis of heart rate variability; blood pressure; and venous plasma concentrations of lactate, adrenaline, and noradrenaline. RESULTS: During the control exercise period there were no changes in the assessed variables compared with the preceding resting period. During exercise at a heart rate of 100 beats/min systolic blood pressure increased and heart rate variability decreased. During exercise at a heart rate of 150 beats/min systolic blood pressure and lactate, adrenaline, and noradrenaline concentrations increased. In addition, low frequency (LF) was lower than during exercise at 100 beats/min, high frequency (HF 0.15-0.80 Hz) resembled that during exercise at 100 beats/min, and diastolic blood pressure was reduced. Infusion of atropine caused no changes in blood pressure or plasma concentrations of lactate, adrenaline, and noradrenaline and decreased heart rate variability. The additional infusion of adrenaline and noradrenaline completely suppressed heart rate variability and increased blood pressure. CONCLUSIONS: The reduction in LF and HF during exercise at a heart rate of 100 beats/min, which is not characterised by increased plasma catecholamine concentrations, and during atropine infusion suggests that heart rate variability in the supine state is largely influenced by vagal activity. The additional reduction in LF during exercise at 150 beats/min and during catecholamine infusion may reflect a negative feedback of circulating catecholamines on the sympathetic control of heart rate.

Adult↗
PubMed1985

Absence of rebound from diltiazem therapy in Prinzmetal's variant angina.

To determine the frequency of rebound anginal symptoms on abrupt withdrawal of calcium channel blocking agents, anginal symptoms were retrospectively examined in patients with Prinzmetal's variant angina abruptly withdrawn from diltiazem therapy as part of the design of a placebo-controlled multiple crossover trial. Rebound was defined as a return of anginal symptoms to levels exceeding those of the pretreatment baseline state. Values for daily frequency of angina were compared (after subtracting corresponding baseline values) between placebo periods following diltiazem periods and placebo periods following placebo periods. No intergroup differences existed between mean changes in daily frequency of angina from baseline value (-0.61 for placebo following diltiazem versus -1.10 for placebo following placebo) (p greater than 0.4). Furthermore, in 13 (28%) of 46 occurrences when placebo followed placebo, daily frequency of angina exceeded baseline value in the immediate 3 day period following placebo compared with 17 (21%) of 80 occurrences when placebo followed diltiazem. There was no increased rebound occurrence comparing high dose (240 mg/day) with low dose (120 mg/day) diltiazem therapy. No significant symptoms such as myocardial infarction or unstable angina occurred after withdrawal of diltiazem or placebo. The lack of difference in rebound after diltiazem or placebo withdrawal was consistent using paired and unpaired analyses. In conclusion, there appears to be no evidence that abrupt withdrawal of therapy with diltiazem results in rebound anginal symptoms.

Angina Pectoris, Variant↗
PubMed1980

Bacteriophage lambda cloning vehicles for studies of genetic recombination.

A pair of bacteriophage lambda cloning vehicles has been constructed for use in studies of genetic recombination. These phages, lambda rva and lambda rvb, have the following properties: (1) Each vector has a single HindIII site in the immunity region, at which segments of DNA can be inserted. (2) These HindIII sites are flanked by selectable markers with the following phenotypes: Spi+/- (Fec+/-) to the left, and imm lambda or imm434 to the right. (3) There is essentially no sequence homology between the two phages in this region, so recombination of the markers at reasonable frequency depends on the presence of homologous inserts at the HindIII sites. As a consequence, recovered recombinants must have resulted from a crossover event within the insert DNA. Restriction enzyme maps of the vectors have been determined. Variants of the original vectors have been isolated which permit separate examination of the viral (Red) and bacterial (Rec) generalized recombination mechanisms, and which provide a standard interval to which frequencies of recombination in cloned DNAs can be compared.

Bacteriophage lambda↗
PubMed2003

Comparison of changes in uterine contraction frequency after ovulation in the menstrual cycle and in in vitro fertilization cycles.

OBJECTIVE: To compare changes in uterine contraction (UC) frequency occurring after ovulation in the menstrual cycle and in IVF and to clarify UC anomalies encountered in IVF. DESIGN: Prospective crossover trial. SETTING: University infertility clinic. PATIENT(S): Six women seeking IVF for male factor infertility having regular menstrual cycles were studied during the menstrual cycle and IVF. INTERVENTION(S): Identification of LH surge in the menstrual cycle. Measurement of plasma E(2) and P levels and assessment of UC frequency by direct ultrasound visualization on the day of LH surge in the menstrual cycle and the day of hCG administration in IVF and every 2 days thereafter for 6 days. MAIN OUTCOME MEASURE(S): Uterine contraction (UC) frequency and plasma E(2) and P levels. RESULT(S): UC frequency was similar on the day of LH surge (5/minute) and hCG administration (5.3/minute). Establishment of uteroquiescence was more prompt in the menstrual cycle than in IVF, with lower UC frequency 4 days after LH surge compared with 4 days after hCG, while E(2) and P levels were higher in IVF. Six days after LH surge/hCG administration, UC frequency was low in the menstrual cycle and in IVF. CONCLUSION(S): High UC frequency in IVF at the time of ET results from delayed establishment of uteroquiescence after ovulation in IVF as compared with the menstrual cycle. In IVF, low UC frequency 6 days after hCG may contribute to the higher pregnancy rates observed with blastocyst transfers.

Adult↗
PubMedDate not supplied

Modeling the diagnosis of stroke at two hospitals.

A comparison of five major categories of stroke in 651 patients revealed significant differences in the frequencies of diagnoses at the Beth Israel and Massachusetts General hospitals in Boston, Mass. (P less than 0.001 by chi-square test). To analyze these differences, we modeled the diagnostic process at each hospital with a Bayesian procedure and performed a crossover study in which each patient was rediagnosed by the model from the opposite hospital. The results indicate that the differences in the frequency of lacune and subarachnoid hemorrhage were associated with the patient population, whereas the differences in the frequency of embolism and atherothrombosis were associated with the diagnostic process. There was a marked difference in the use of arteriograms on the two stroke services, but no difference in morbidity or mortality. The modeling procedure described can be used to compare clinical processes when the allocation of patients is thought to be biased.

Bayes Theorem↗
PubMed2003

Frequency of surgery among children who have adenotonsillar hypertrophy and improve after treatment with nasal beclomethasone.

OBJECTIVE: To describe the long-term outcome of a cohort of children with symptomatic adenotonsillar hypertrophy treated with aqueous nasal beclomethasone. METHODS: The children enrolled completed a 4-week single-blind, saline solution controlled crossover study of aqueous beclomethasone (total: 400 micro g/d). In a 24-week open-label follow-on study, beclomethasone 200 micro g/d was offered to all patients. During a 100-week follow-up, the degree of nasal obstruction and the frequency of adenotonsillectomy were assessed. RESULTS: Fifty-three children of the 60 enrolled completed the study. After the 4-week crossover trial, the severity of nasal obstruction of 24 children (45%) significantly decreased during the use of nasal steroids, but no child improved when saline solution was used. At 24, 52, and 100 weeks, the 24 children who had initially improved showed a significant decrease of the severity of nasal obstruction and of the frequency of adenotonsillectomy (54% vs 83%) compared with the 29 children who had not responded after the initial steroidal therapy. CONCLUSIONS: Evidence from this study suggests that 45% of children with adenoidal hypertrophy improved after 2 weeks of steroidal therapy. Among these children, an additional 24-week treatment at a lower steroid dosage was associated with a significant 52- and 100-week clinical improvement and with reduction of adenotonsillectomy compared with children (55%) who had not responded after the initial 2-week steroidal therapy.

Adenoidectomy↗