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PubMed2002

Pilot study of coronary atherosclerotic risk and plaque burden in HIV patients: 'a call for cardiovascular prevention'.

BACKGROUND: Highly active antiretroviral therapy (HAART) has dramatically improved the life expectancy of patients with human immunodeficiency virus (HIV) prompting increasing concerns related to chronic management. Suggestions of greater cardiovascular risk, partially related to recently proposed HAART-induced dyslipidemia and glucose intolerance, amplify these concerns. At this time, further corroboration of the emerging evidence for increased coronary risk, as well as complimentary estimates of coronary artery atherosclerotic burden, would be valuable to practicing physicians. METHODS: Seventeen HIV patients on HAART (all from the same HIV clinic population) without coronary artery disease (CAD) were referred to Preventive Cardiology for treatment of dyslipidemia ('referred group'). Upon entry, they underwent computed tomography (CT) of the coronary arteries. Subsequently, the referred group was matched (1:4) for age, gender and traditional risk to non-HIV non-CAD subjects (matched group, n=68) from the University of Illinois CT database. A serial review of 90 subjects from the original HIV population was sampled to determine general cardiovascular risk. RESULTS: Thirteen (76%) of the 17 referred patients revealed the presence of coronary calcium compared with 63% in the matched HIV seronegative controls (P=0.18). Log-transformed median calcium score was 2.93+/-2.3 in the referred group versus 1.97+/-2.5 in the matched group (P=0.09). Fifty one percent of the overall population smoked cigarettes, 11% were diabetic (30% diagnosed pre-HAART and 70% post-HAART) and 30% were hypertensive (33% diagnosed pre-HAART and 67% post-HAART). CONCLUSIONS: In a particularly dyslipidemic subgroup of HIV subjects without known CAD we found evidence for atherosclerosis in three-quarters based on coronary calcium. Further, in this population of HIV patients on HAART, we found an enhanced prevalence of traditional cardiovascular risk. This pilot study encourages the development of preventive strategies in this population.

Adult↗
PubMed2004

Is eligibility for a chemotherapy protocol a good prognostic factor for invasive bladder cancer after radical cystectomy?

PURPOSE: To assess whether eligibility to an adjuvant chemotherapy protocol in itself represents a good prognostic factor after radical cystectomy for bladder cancer. PATIENTS AND METHODS: Between April 1984 and May 1989, our institution entered 35 patients with invasive bladder cancer into the Swiss Group for Clinical and Epidemiological Cancer Research (SAKK) study 09/84. They were randomly assigned to either observation or three postoperative courses of cisplatin monotherapy after cystectomy. This study had a negative result. The outcome of these 35 patients (protocol group) was compared with an age- and tumor-stage-matched cohort (matched group; n = 35) who also underwent cystectomy during the same period, but were not entered into the SAKK study, as well as the remaining 57 patients treated during the study period for the same indication (remaining group). RESULTS: Median overall survival decreased from 76.3 months in the protocol group to 52.1 months in the matched group and to 20.3 months in the remaining group. The respective times of median recurrence-free survival were 67.2, 16.0, and 9.4 months. Tumor progression occurred in 46% of the protocol group compared with 69% in the matched group and 65% in the remaining group (P < .05). Cancer-related death was noted in 40% of the protocol group, 57% in the matched group, and 56% in the remaining group. CONCLUSION: These data suggest that being willing and fit enough for a chemotherapy protocol is a good prognostic factor for invasive bladder cancer. This eligibility bias emphasizes the need for prospective, randomized trials, and indicates that single-group studies using historical or matched controls have to be interpreted with caution.

Aged↗
PubMed1991

Pulmonary valve-moderator band distance and association with development of double-chambered right ventricle.

Double-chambered right ventricle (DCRV), a form of right ventricular outflow obstruction that sometimes accompanies a ventricular septal defect (VSD), is associated with superior and rightward displacement of the septal insertion of the moderator band. It was hypothesized that this superior displacement is present and identifiable by echocardiography in patients with a VSD even before right ventricular outflow tract obstruction develops. Eight patients who had a previous echocardiographic study showing a VSD alone were echocardiographically diagnosed as having DCRV. Their initial echocardiographic studies were reviewed, and superior displacement of the moderator band was quantified by measuring the distance between the pulmonary valve and moderator band, normalized to tricuspid anulus diameter. These measurements were compared with those from the initial studies of the following 3 other groups: (1) an age-matched group of 10 patients with no structural heart disease; (2) an age-matched group of 10 patients with a VSD who did not develop DCRV; and (3) a group (not age-matched) of 10 patients with VSD and DCRV in whom subpulmonary obstruction was present on the initial study. The 8 patients who eventually developed subpulmonary obstruction had significant superior displacement of the moderator band at the time of their initial echocardiogram compared with that of the 2 age-matched control groups (p less than 0.01). In contrast, there was no significant difference in moderator band displacement between these patients and the 10 with DCRV who already had right ventricular outflow obstruction at their initial study (p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2003

Grammatical morpheme effects on MLU: "the same can be less" revisited.

Studies of children with specific language impairment (SLI) often include 2 comparison groups of typically developing children--a group matched according to age and a group matched according to mean length of utterance (MLU). In these studies, both groups of typically developing children often perform better than the SLI group. For many of these investigations, grammatical morpheme use constitutes the dependent measure. The use of grammatical morphemes requires longer utterances than the failure to use these morphemes. If children with SLI show less use of grammatical morphemes than typically developing children matched for MLU, shouldn't they produce some other detail of language more frequently than the MLU-matched group? In this article, the authors report 2 studies showing that such offsetting effects are not necessary in principle, given the nature of MLU. The implications of these findings are discussed.

Case-Control Studies↗
PubMed1994

Polydipsia amongst adults with a learning disability in an institution.

A hospital-based adult learning disabled population (n = 371) was screened for polydipsia with the help of a purpose-designed questionnaire. Polydipsia was defined as excessive drinking of more than 3 l of non-alcoholic fluid over a 24-h period. Altogether, 23 (6.2%) subjects were found to have polydipsia. The polydipsic group was compared with the whole hospital population on variables such as age and IQ distribution. A matched group of 23 individuals without a history of polydipsia was drawn from the same hospital population. The polydipsic and the matched group were compared using various biochemical and psychological measures. Thirty-five per cent of polydipsic patients, compared to 13% of the matched group, showed evidence of compensated hyponatraemia. This difference was not significant. There was no significant difference between the polydipsic and the matched group in the frequency of psychiatric illness, behavioural problems or autism. There also was no significant difference in the IQ levels of the polydipsic patients and the total hospital population. Polydipsia in this population is largely seen as part of an abnormal behavioural repertoire without any evidence of possible organic cause, except unidentified diabetes mellitus. Klein Levin syndrome and pica were represented in the polydipsic group, but not amongst the matched group.

Adult↗
PubMed1990

Effects of irradiation and semistarvation on rat thyrotropin beta subunit messenger ribonucleic acid, pituitary thyrotropin content, and thyroid hormone levels.

The effect of radiation-induced anorexia on serum thyrotropin (TSH), pituitary TSH-beta mRNA, pituitary TSH content, serum thyroxine (T4), and serum 3,5,3'-triiodothyronine (T3) was investigated using feed-matched controls. Rats received 10 Gy gamma whole-body irradiation and were examined 1-3 days postirradiation. Feed-matched and untreated controls were also studied. The average food intake of the irradiated and feed-matched groups was approximately 18% of the untreated controls. Over the three day period both the irradiated and feed-matched groups lost a significant amount of body weight. The serum T4 levels of both the irradiated and feed-matched groups were not significantly different from each other, but were significantly depressed when compared to the untreated control group. The serum TSH and T3 were, however, significantly greater in the irradiated than the feed-matched groups at day 3 posttreatment. To determine if the difference in the serum TSH level between the two groups was due to a pretranslational alteration in TSH production, we measured the TSH-beta mRNA using an RNA blot hybridization assay. We found that the TSH-beta mRNA level was the same in the irradiated and feed-matched groups, suggesting that the mechanism responsible for the radiation-induced increase in the serum TSH level is posttranscriptional. Pituitary TSH content in the irradiated rats was significantly less than in pair-fed controls, suggesting that irradiation may permit enhanced secretion of stored hormone.

Animals↗
PubMed1996

Cementless total knee arthroplasty in obese patients. A comparison with a matched control group.

The heaviest 45 patients (50 knees) who underwent cementless total knee arthroplasty were compared with a matched control group of 45 total knee arthroplasty patients (50 knees) with respect to clinical and radiographic data. Surgery was performed over a 10-year period (1980-1989) and follow-up evaluation averaged 7 years (range, 2-11 years). The control group consisted of nonobese patients matched to the obese group with respect to age, sex, diagnosis, preoperative deformity, and length of follow-up evaluation. Clinical evaluation was made using the Knee Society rating scale as well as an analysis of multiple other clinical parameters. Radiographically, each patient was evaluated with long-standing anteroposterior views, lateral and patellar views, and spot fluoroscopic views of the involved knee. This evaluation included an analysis of lucencies, bead shedding, and prosthetic alignment. The final average clinical score in the obese group was 88 points with four revisions, and that for the control group was 91 points with two revisions. There were no significant differences in the combined percentage of good and excellent results between the two groups. On the basis of the results of this study, it is believed that weight as a factor by itself should not compromise the early (7-year average follow-up period) results of total knee arthroplasty.

Adult↗
PubMed2006

Narrow-linewidth near-degenerate optical parametric generation achieved with quasi-group-velocity-matching in lithium niobate waveguides.

We demonstrate narrow-linewidth near-degenerate optical parametric generation in reverse-proton-exchange lithium niobate waveguides with quasi-group-velocity-matching, which is realized by using wavelength-selective directional couplers and tight-radius bends. With appropriate designs for 1.6 ps long pump pulses at 785.1 nm we obtained near-degenerate signal (idler) pulses with a time-bandwidth product as low as 1.1, compared with 10.5 for conventional devices without quasi-group-velocity-matching. This improvement in the temporal property is a result of both a pulse compression effect and a filter effect coming from our scheme of quasi-group-velocity-matching.

Journal Article↗
PubMed1997

White matter lesions in patients with idiopathic normal pressure hydrocephalus and in an age-matched control group: a comparative study.

OBJECTIVE: To compare the occurrence of periventricular lesions (PVLs) and deep white matter lesions (DWMLs) in elderly patients with idiopathic normal pressure hydrocephalus (NPH) and in an age-matched control group. METHODS: PVLs and DWMLs were evaluated using T2-weighted magnetic resonance scans of 37 patients with idiopathic NPH and 35 participants from an age-matched control group. All patients with idiopathic NPH included in this study improved after shunting. The control group consisted of 16 healthy elderly persons and 19 patients with depression. To allow quantitative assessment and comparison, scores for PVLs and DWMLs were calculated. Furthermore, possible correlations between white matter lesion scores, ventricular width, and age were investigated. RESULTS: There was a significantly higher incidence of PVLs and DWMLs in patients with idiopathic NPH. The mean total PVL was 12.1 (range, 2-24) in the NPH group and 3.9 (range, 0-10) in the control group (P < 0.001). The mean total DWML score was 12.9 (range, 3-24) in the NPH group and 4.5 (range, 0-16) in the control group (P < 0.001). There were significant correlations between the severity of PVL and DWML scores in both groups. Only a weak positive correlation between the severity of DWMLs and age was found in the NPH group, whereas this correlation was significant in the control group. There was a significant negative correlation between the width of the anterior horns and the severity of both PVLs and DWMLs in patients with NPH; however, positive correlations were found in the control group. CONCLUSION: Elderly patients with idiopathic NPH have more frequent and more severe PVLs and DWMLs than people in age-matched control groups. Our data suggest a frequent co-occurrence of idiopathic NPH and vascular subcortical encephalopathy; however, they do not support a direct causal relationship.

Aged↗
PubMed1998

Late outcome of coronary artery bypass grafting in young versus older patients.

BACKGROUND: We compared long-term results of coronary artery bypass grafting between 1976 and 1988 in 176 patients 40 years old or younger with a matched control group of 176 patients 25 to 30 years older. METHODS: Mean age was 37.4 +/- 2.7 years (+/- standard deviation) in the study group and 64.2 +/- 2.9 years in the control group. Matching criteria were age, sex, left ventricular ejection fraction, number of bypass grafts, and year of operation. RESULTS: The study group had more smokers (p = 0.000) and more patients with hypercholesterolemia (p = 0.026), unstable angina (p = 0.003), and preoperative myocardial infarction (p = 0.009); fewer patients had hypertension (p = 0.000) and diabetes (p = 0.005) in this group than in the control group. The internal mammary artery was used in 31% of the study patients and in 30% of the controls. The actuarial survival rates after 5, 10, and 15 years were 92%, 86%, and 72% in the study group and 92%, 86%, and 66% in the control group (p = 0.202). Young age was a predictor of cardiac reoperation. CONCLUSIONS: Late survival is similar for young and older patients, but the reintervention rate is higher in the younger group. The absence of unstable angina, a left ventricular ejection fraction greater than 0.45, and the use of internal mammary artery grafts increase survival in all patients.

Adult↗
PubMed1998

Effectiveness of a home program intervention for young children with autism.

This project evaluated the effectiveness of a TEACCH-based home program intervention for young children with autism. Parents were taught how to work with their preschool autistic child in the home setting, focusing on cognitive, academic, and prevocational skills essential to later school success. To evaluate the efficacy of the program, two matched groups of children were compared, a treatment group and a no-treatment control group, each consisting of 11 subjects. The treatment group was provided with approximately 4 months of home programming and was tested before and after the intervention with the Psychoeducational Profile-Revised (PEP-R). The control group did not receive the treatment but was tested at the same 4-month interval. The groups were matched on age, pretest PEP-R scores, severity of autism, and time to follow-up. Results demonstrated that children in the treatment group improved significantly more than those in the control group on the PEP-R subtests of imitation, fine motor, gross motor, and nonverbal conceptual skills, as well as in overall PEP-R scores. Progress in the treatment group was three to four times greater than that in the control group on all outcome tests. This suggests that the home program intervention was effective in enhancing development in young children with autism.

Achievement↗
PubMed1986

Midforceps deliveries: long-term outcome of infants.

Infants delivered by midforceps between 1976 and 1982 were evaluated for evidence of developmental delay or neurological deficit by chart review. The 110 infants who were followed for at least 2 years were compared to a matched group of infants delivered by cesarean section. The cesarean section group was matched for the immediate indication for delivery (dystocia or fetal distress), birth weight, gestational age, sex, and race. There was no significant difference in abnormal outcomes in the two groups.

Birth Injuries↗
PubMedDate not supplied

[Gestational characteristics in women with breast cancer].

In a survey of 250 women with breast cancer and 250 healthy women from a matched control group (matching in age, nationality, and residence) no significant difference was found between the diseased and the healthy women in the average number of pregnant women and the average duration of pregnancy. In the group of the diseased there were significantly more women with 1--2 pregnancies, i.e. below modal values in the healthy women (P < 0.10), and also a higher number of women with more frequent pregnancies. No significant difference was found in the number of nulliparas, but in the diseased both a larger and a smaller number of births in relation to the modal values of both groups (2 births) were characteristic, There was no significant difference in the distribution of the first delivery according to the women's age. The diseased had significantly fewer artificial abortuses (P < 0.001). There were more healthy women with 1--5 abortuses (P < 0.001) while the number of women with 5 and over 5 abortuses was the same in both groups. The number of women with spontaneous abortus proved significantly higher in the diseased than in the group of healthy women (P < 0.10). No evidence was obtained concerning the protective role of breast feeding which lasted longer in the diseased, both in the period of intensive breast breeding and following this period.

Abortion, Induced↗
PubMed1991

Recognition of affective facial expressions by children and adolescents with and without mental retardation.

Children and adolescents with mental retardation were compared with children and adolescents without mental retardation on their ability to recognize facial expressions. The groups were matched for either chronological age (CA) or mental age (MA). Children and adolescents with mental retardation recognized facial expressions less accurately than did subjects without retardation who were matched on CA. The MA-matched groups showed no differences in accuracy at the younger MA but a difference was found at the older MA. However, subjects categorized as having cultural-familial retardation did not differ from subjects without retardation matched for MA at either the younger or older MA. Results suggest that children with mental retardation are less able than children without retardation to develop emotional recognition skills by observational learning.

Adolescent↗
PubMed1999

Cochlear implantation in auditory neuropathy.

OBJECTIVE: Auditory neuropathy is a recently described clinical entity characterized by sensorineural hearing loss in which the auditory evoked potential (ABR) is absent but otoacoustic emissions are present. This suggests a central locus for the associated hearing loss. In this study the results observed in a child with auditory neuropathy who received a cochlear implant are presented and compared with those of a matched group of children who were recipients of implants. METHODS: A single-subject, repeated-measures design, evaluating closed-set and open-set word recognition abilities was used to assess the subject and a control group of matched children with implants who had also experienced a progressive sensorineural hearing loss. RESULTS: The subject demonstrated improvements in vowel recognition (82% correct) by 1 year after implantation, which were only slightly lower than the control group. Consonant recognition and open-set word recognition scores were significantly lower. CONCLUSION: Caution should be exercised when considering cochlear implantation in children with auditory neuropathy. As with conventional hearing aids, less than optimal results may be seen.

Audiometry, Pure-Tone↗
PubMed2000

Immediate and long-term results comparing coronary versus biliary tubular-slotted stents to treat old obstructed saphenous vein grafts.

Stenting of old obstructed saphenous vein grafts improves immediate angiographic results and long-term clinical outcome compared to standard balloon angioplasty. Comparison of results and long-term clinical outcome between different types of stents in the treatment of vein graft disease is scarce. The authors studied two matched groups of 33 patients each, receiving either coronary or biliary tubular-slotted stents in old vein graft lesions to compare immediate results and long-term clinical outcome. Patients in the two groups were matched for age and left ventricular function. Baseline angiographic characteristics, the minimal luminal diameter (MLD) (0.68 +/- 0.56 mm vs 0.61 +/- 0.51 mm, p = 0.9), and diameter stenosis (DS) (81 +/- 14% vs 82 +/- 15%) were similar between the groups. After stenting, the MLD (3.15 +/- 0.65 mm vs 3.37 +/- 0.63 mm, p = 0.9) and residual stenosis (-7 +/- 19% vs -11 +/- 21%) were also similar. The in-hospital major complications (myocardial infarction and death) (one vs eight, p = 0.01) and the combination of major and minor (bleeding and vascular) complications (eight vs 17, p = 0.02) were higher in the biliary stent group. At long-term follow-up, both groups of patients had high but comparable rates of major cardiovascular events (39% vs 45%, p = 0.62). Kaplan-Meier event-free survival analysis did not show any statistically significant difference in event-free survival (log-rank statistic 0.98). The authors conclude that patients receiving biliary stents had higher rates of immediate minor and major complications, but at long-term follow up, major cardiovascular event rates were comparable between the two groups of patients.

Aged↗
PubMed2002

Effect of acetabular modularity on polyethylene wear and osteolysis in total hip arthroplasty.

BACKGROUND: Debris from polyethylene wear causes osteolysis. In this study, we examined the effect of acetabular liner modularity on polyethylene wear and osteolysis. METHODS: We compared forty-one hips (thirty-nine patients) treated with a nonmodular, porous-coated acetabular component with a matched group of forty-one hips (forty patients) treated with a modular acetabular component. The groups were matched by patient gender and age, type of polyethylene material, method of polyethylene sterilization, femoral head size and manufacturer, and stem manufacturer. The mean follow-up period was 5.3 years (range, 3.8 to 6.8 years) for the nonmodular group and 5.5 years (range, 3.8 to 8.0 years) for the modular group. Using serial radiographs and a computer-assisted method, we measured two-dimensional head penetration into the polyethylene liner. Temporal head-penetration data and linear regression analysis were used to calculate the true wear rates. RESULTS: The nonmodular acetabular components demonstrated a lower, but not a significantly lower, mean true wear rate than did the modular components (0.11 compared with 0.16 mm/yr, p = 0.22), and they were associated with a significantly lower rate of osteolysis (2% compared with 22%, p = 0.01). In addition, the true wear rates of the nonmodular components were less variable than those of the modular components. The 95% confidence interval for the wear rates of the nonmodular components (0.08 to 0.13 mm/yr) was nearly half that of the modular group (0.11 to 0.20 mm/yr). CONCLUSIONS: The lower and more consistent true wear rates of the nonmodular components could be attributed to the fact that these cups were designed to have greater liner-shell conformity, greater liner thickness, and less liner-shell micromotion than modular components. These design factors could have favorably altered the stress distribution throughout the liner and could have thereby decreased wear. Although nonmodular components may present a partial solution to the problems of wear and osteolysis, they pose a disadvantage when a failed liner in a bone-ingrown acetabular component needs to be revised.

Acetabulum↗