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PubMed2000

Cross-reactive group matching does not lead to a better allocation and survival of donor kidneys.

BACKGROUND: In cadaveric renal transplantation HLA-A, -B, -DR matching of donor and recipient is beneficial for graft survival. However, allocation based on HLA matching seems to favor recipients with more frequently occurring HLA antigens. In this study we investigated whether matching on the basis of cross-reactive groups (CREGs), defined according to the United Network for Organ Sharing (UNOS), would be a good alternative for the allocation of kidneys without negatively influencing graft survival. Theoretically, this approach would provide more recipients with an immunologically well-matched donor organ. METHODS: The influence of CREG matching on graft survival was studied in univariate analyses using the Eurotransplant database. RESULTS: No beneficial effect of CREG matching was observed, whereas a significant HLA matching effect was observed in the 0 CREG mismatched donor/ recipient combinations. Only in the small subgroup with 1 MM for HLA-A, -B and 0 MM for HLA-DR, a significantly better survival was observed, when this mismatch belonged to the 0 or 1 MM CREG group versus two or more MM CREG group. However, this subgroup concerns only 8% of the transplants performed. CONCLUSIONS: In contrast to other reports, our study showed that HLA matching is by far more beneficial than CREG matching. In the homogenous Eurotransplant population, adjusting the matching criteria toward CREG matching would not lead to an improved graft survival.

Cross Reactions↗
PubMed2005

Hamstring tendon versus patellar tendon anterior cruciate ligament reconstruction using biodegradable interference fit fixation: a prospective matched-group analysis.

BACKGROUND: There are still controversies about graft selection for primary anterior cruciate ligament reconstruction, especially with respect to knee stability and functional outcome. HYPOTHESIS: Biodegradable interference screw fixation of hamstring tendon grafts provides clinical results similar to those achieved with identical fixation of bone-patellar tendon-bone grafts. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: In 1996 and 1997, primary isolated anterior cruciate ligament reconstruction using a bone-patellar tendon-bone autograft was performed in 72 patients. Since 1998, hamstring tendons were used as routine grafts. Matched patients with a hamstring tendon graft were selected from a database (n = 284). All patients were followed prospectively for a minimum of 2 years with KT-1000 arthrometer testing, International Knee Documentation Committee score, and Lysholm score. RESULTS: In the bone-patellar tendon-bone group, 9 patients were excluded because of bilateral rupture of the anterior cruciate ligament, 3 patients (4.2%) had a graft rupture, and 4 patients were lost to follow-up (follow-up rate, 92.1%), leaving 56 patients for a matched-group analysis. In the hamstring tendon database, the graft rupture rate was 5.6% (P = .698). The Lysholm score was 89.7 in the patellar tendon group and 94 in the hamstring tendon group (P = .003). The KT-1000 arthrometer side-to-side difference was 2.6 mm for the patellar tendon group and 2.1 mm for the hamstring tendon group (P = .041). There were significantly less positive pivot-shift test results in the hamstring tendon group (P = .005), and hamstring tendon patients showed lower thigh atrophy (P = .024) and patellofemoral crepitus (P = .003). Overall International Knee Documentation Committee scores were better (P = .001) in the hamstring tendon group (hamstring tendon: 34 x A, 21 x B, 0 x C, 0 x D; bone-patellar tendon-bone: 17 x A, 32 x B, 6 x C, 0 x D). CONCLUSIONS: In this comparison of anterior cruciate ligament reconstruction with bone-patellar tendon-bone and anatomical hamstring tendon grafts, the hamstring tendon graft was superior in knee stability and function. These findings are partially contrary to previous studies and might be attributable to the use of an anatomical joint line fixation for hamstring tendon grafts. Thus, hamstring tendons are the authors' primary graft choice for anterior cruciate ligament reconstruction, even in high-level athletes.

Adolescent↗
PubMed2000

Effects of gestation and birth weight on the growth and development of very low birthweight small for gestational age infants: a matched group comparison.

AIMS: To investigate the effects of small for gestational age (SGA) in very low birthweight (VLBW) infants on growth and development until the fifth year of life. METHODS: VLBW (< 1500 g) infants, selected from a prospective study, were classified as SGA (n = 115) on the basis of birth weight below the 10th percentile for gestational age and were compared with two groups of appropriate for gestational age (AGA) infants matched according to birth weight (AGA-BW; n = 115) or gestation at birth (AGA-GA; n = 115). Prenatal, perinatal, and postnatal risk factors were recorded, and duration and intensity of treatment were computed from daily assessments. Body weight, length, and head circumference were measured at birth, five and 20 months (corrected for prematurity), and at 56 months. General development was assessed at five and 20 months with the Griffiths scale of babies abilities, and cognitive development at 56 months with the Columbia mental maturity scales, a vocabulary (AWST) and language comprehension test (LSVTA). RESULTS: Significant group differences were found in complications (pregnancy, birth, and neonatal), parity, and multiple birth rate. The AGA-GA group showed most satisfactory growth up to 56 months, with both the AGA-BW and SGA groups lagging behind. The AGA-GA group also scored significantly more highly on all developmental and cognitive tests than the other groups. Developmental test results were similar for the SGA and AGA-BW groups at five and 20 months, but AGA-BW infants (lowest gestation) had lower scores on performance intelligence quotient and language comprehension at 56 months than the SGA group. When prenatal and neonatal complications, parity, and multiple birth were accounted for, group differences in growth remained, but differences in cognitive outcome disappeared after five months. CONCLUSIONS: Being underweight and with a short gestation (SGA and VLBW) leads to poor weight gain and head growth in infancy but does not result in poorer growth than in infants of the same birth weight but shorter gestation (AGA-BW) in the long term. SGA is related to early developmental delay and later language problems; however, neonatal complications may have a larger detrimental effect on long term cognitive development of VLBW infants than whether they are born SGA or AGA.

Birth Weight↗
PubMed1975

Comparison of Rorschach anatomy responses from psychosomatic out-patients and a matched group of psychiatric controls.

35 out-patient Ss with demonstrable psychosomatic symptoms were matched with 35 psychiatric out-patients with "milder" forms of psychopathology, i.e., neurosis, personality disorders and latent schizophrenia. The psychosomatic group showed significantly more anatomy responses on the Rorschach but there was much overlap, leading to the conclusion that anatomy does not directly reflect simply psychosomatic disturbances but, rather, is associated with psychodynamics which tend to underlie psychosomatic illnesses.

Adolescent↗
PubMed1996

Quality of life in long-term survivors of marrow transplantation: comparison with a matched group receiving maintenance chemotherapy.

A retrospective descriptive study was designed to assess the quality of life (QoL) and psychosocial adjustment in long-term BMT survivors compared with a group of patients with haematological malignancies receiving maintenance chemotherapy (MC), matched for age, post-treatment time, sociodemographic and disease characteristics. The sample consisted of 91 long-term BMT survivors and 73 MC patients from three teaching hospitals in the UK. The results indicated that most of the BMT subjects had a good to excellent quality of life and, in some domains, even better adjustment than the MC patients. However, 20% of the BMT subjects had failed to return to full-time employment at a mean post-BMT time of almost 40 months. A significant number of BMT subjects were also identified with symptoms of anxiety and depression. The physical symptomatology had an association with psychological status. Impotence-related difficulties, decreased sexual satisfaction and altered body image were the main characteristics of psychosexual dysfunction in the BMT group. Poorer quality of life was predicted by the presence of depressive symptoms, low affirmation, and impoverished social adjustment.

Adolescent↗
PubMed1998

Femoral trabecular bone of osteoarthritic and normal subjects in an age and sex matched group.

OBJECTIVE: To describe changes to the cancellous structure of femoral bone from patients with severe primary osteoarthritis by comparison with age and sex matched controls. METHOD: Specimens were taken from 18 male and 18 female pairs. One of each pair was a normal control, the other having severe primary osteoarthritis which required hip arthroplasty. Undecalcified cancellous bone blocks were embedded in resin, sectioned and impregnated with silver. Histoquantitation was performed using image analysis. Using a plate model for the trabecular structure of bone, an estimate was made of bone volume, bone surface, trabecular thickness, trabecular separation and trabecular number. RESULTS: In osteoarthritis, pooled male and female data show a significant decrease in trabecular number together with an increase in trabecular thickness and separation. The statistical variance in the histomorphometric variables for each of the study groups was calculated and expressed as the ratio of osteoarthritic to control. This ratio shows that the variance of the osteoarthritic groups is significantly increased for each variable in the pooled data. The same trend is evident in the male and female groups. CONCLUSIONS: This quantitative study of cancellous bone architecture in the femoral head, infero-medial to the fovea, has found increased trabecular thickness and decreased trabecular number in patients with primary osteoarthritis. Increased morphometric variance has shown that severe osteoarthritis, contrary to osteoporosis, is associated with heterogeneous bone structures. These findings provide some basis for understanding how osteoarthritis may contribute to the prevention of osteoporotic fracture.

Aged↗
PubMed1997

Temporal trends in drug use in one UK region, revealed by chemical group matching.

(1) The pharmaceutical pricing data for Northern Ireland were amended to include defined daily dosages (DDD) for all single chemical entities. Eight therapeutic groups were studied: antiasthmatics, antidepressants, antimicrobials, benzodiazepines, hormone replacement therapy (HRT), hypoglycaemics, lipid-lowering agents and ulcer-healing drugs. Each group was then subdivided into its main chemical groups. The regional use of each chemical group was defined as the combined DDDs of its individual chemical entities per quarter year, from January 1989 until December 1994. (2) During this period, drug use increased in all eight therapeutic groups and in most of their constituent chemical groups. Increased use of newer drugs did not cause the expected decrease in use of established drugs. Use of all broad-spectrum antimicrobials increased by 314%. Use of sedative benzodiazepines decreased slowly and steadily (16%) throughout the study period but use of all hypnotics increased inexplicably by 21% in 1992 reaching a plateau in 1993 and 1994. SSRI antidepressant use increased sharply (5333%) following their introduction in 1989, accompanied by a 24% increase in use of tricyclic antidepressants. There was a 23,626% increase in the use of proton pump inhibitors and a smaller but steady increase of 38% in use of histamine H(2) antagonists; it is unlikely that much of the prescribing of anti-ulcer and antimicrobials was accurately targeted and rationally defensible. (3) More positively, use of beta(2)-agonist inhalers increased by 45% despite a 254% increase in the use of inhaled steroids. Use of HRT increased by 389% though evidence of under-use is given. There was a steady increase in the use of both insulins (28%) and oral hypoglycaemics (34%). The use of 'statins' (690%) and fibrates (123%) increased. (4) The possible interpretations and implications of these patterns of drug use is discussed, together with their potential as proxies for morbidity incidence in the community.

Journal Article↗
PubMed1997

HLA and cross-reactive antigen group matching for cadaver kidney allocation.

BACKGROUND: Allocation of cadaver kidneys by graded human leukocyte antigen (HLA) compatibility scoring arguably has had little effect on overall survival while prejudicing the transplant candidacy of African-American and other hard to match populations. Consequently, matching has been proposed of deduced amino acid residues of the individual HLA molecules shared by cross-reactive antigen groups (CREGs). We have examined the circumstances under which compatibility with either method impacted graft survival. METHODS: Using Cox proportional hazards regression modeling, we studied the relationship between levels of conventional HLA mismatch and other donor and recipient factors on primary cadaver kidney survival between 1981 and 1995 at the University of Pittsburgh (n=1,780) and in the United Network for Organ Sharing (UNOS) Scientific Registry during 1991-1995 (n=31,291). The results were compared with those obtained by the matching of amino acid residues that identified CREG-compatible cases with as many as four (but not five and six) HLA mismatches. RESULTS: With more than one HLA mismatch (> 85% of patients in both series), most of the survival advantage of a zero mismatch was lost. None of the HLA loci were "weak." In the UNOS (but not Pittsburgh) category of one-HLA mismatch (n=1334), a subgroup of CREG-matched recipients (35.3%) had better graft survival than the remaining 64.7%, who were CREG-mismatched. There was no advantage of a CREG match in the two- to four-HLA incompatibility tiers. Better graft survival with tacrolimus was observed in both the Pittsburgh and UNOS series. CONCLUSIONS: Obligatory national sharing of cadaver kidneys is justifiable only for zero-HLA-mismatched kidneys. The potential value of CREG matching observed in the one-HLA-mismatched recipients of the UNOS (but not the Pittsburgh) experience deserves further study.

Adolescent↗
PubMed1994

Epilepsy treatment in The Netherlands. Comparison of matched groups of two medical centres.

To test the feasibility of comparing epilepsy treatment policies and outcome, a secondary and a tertiary epilepsy care facility have been audited in a previous study (1). Marked differences were observed in the treatment policies and outcome and in the distribution of seizure types and duration of epilepsy. For this reason the patients of that study were matched according to seizure type and duration of epilepsy, resulting in two groups each of 32 patients per centre. The outcome of treatment was assessed by using clinimetrical indexes for seizure frequency and severity and toxicity of medication, resulting in the Composite Index of Impairments (CII), reflecting all treatment-related impairments. For the statistical analysis the X2-test and the Kruskal-Wallis test were used. Differences were found to be statistically significant when p < 0.05. No distinct differences were found in the treatment policies of both centres. However, differences were observed in the outcome of treatment. The toxicity ratings in this study were significantly higher for the Epilepsy Centre. Also the Composite Index of Impairments (CII) was significantly higher at the Epilepsy Centre. The number of patients with a CII score of > 100 did not differ significantly for both centres. The finding that pharmacotherapy is similar in both centres, suggests that pharmacotherapy is pushed to its limits in both, and that referral to a tertiary facility is mainly for the non-pharmacotherapeutic care modalities available. For the corroboration of this assumption the use of a quality of life index would be more appropriate than the CII.

Adolescent↗
PubMed2005

ADL dependence and perceived health among elderly deaf sign-language users: a comparison with a matched group of elderly hearing people.

The main purpose of the study was to investigate dependence in ADL and perceived health among elderly deaf sign-language users and to compare these findings with data from a matched hearing elderly population sample. Data on the deaf population were collected through assessments and structured interviews in sign language. Data on the hearing population were retrieved from the Swedish National Study and Ageing and Care (SNAC), while only a few variables from the questionnaire were used in the present study. Each deaf individual was matched by three hearing persons. Matching was performed according to gender, age, and living situation. The main finding is that elderly deaf sign-language users are more dependent in ADL but simultaneously report better health than their hearing counterparts. The differences in ADL dependence can be explained by factors linked to the communication problems experienced by deaf sign-language users, but also by cultural factors. The better health reported by the deaf sample may be attributed to adaptive mechanisms that deaf sign-language users have been claimed to develop. This research provides new information on a vulnerable group of elderly people, i.e. deaf sign-language users, that has previously been given little scientific attention.

Activities of Daily Living↗
PubMed1994

Comparison of a community dysthymia sample at screening with a matched group of nondepressed community controls.

The primary goal of the study was to compare the psychosocial functioning of an untreated, community sample of DSM-III-R dysthymia subjects (N = 24) at screening to that of a matched sample of community nondepressed volunteers (N = 18) with no lifetime or current history of axis I disorders. Subjects were compared across a number of psychosocial indices. The dysthymics were found to be less sociable (introversion) and clinically high on neuroticism-instability, external in regard to their causal attributions, less stable for positive uncontrollable events and more stable and global for negative uncontrollable events, relying more on coping strategies such as wishful thinking and self-blame, more interpersonally submissive and hostile, and to have a poorer social support-resource network. In addition, the dysthymics reported more family dysfunction and a higher rate of negative major life events.

Adaptation, Psychological↗
PubMed2005

Perinatal outcome of ICSI pregnancies compared with a matched group of natural conception pregnancies in Flanders (Belgium): a cohort study.

A retrospective cohort study was conducted with an intracytoplasmic sperm injection (ICSI) group and a naturally conceived comparison group. A total of 1655 singleton and 1102 twin ICSI births were studied with regard to perinatal outcome. Control subjects (naturally conceived pregnancies) were selected from a regional registry and were matched for maternal age, parity, place of delivery, year of birth and fetal sex. The main outcome measures were duration of pregnancy, birth weight, Apgar score <5 after 5 min, neonatal complications, perinatal death and congenital malformations. Twin births, when compared with singletons, carry a much higher risk of poor perinatal outcome. For both ICSI singletons and ICSI twins, no significant difference was found between ICSI and naturally conceived pregnancies for all investigated parameters. After excluding like-sex twin pairs, ICSI twin pregnancies were at increased risk for perinatal mortality (OR = 2.74, CI = 1.26-5.98), prematurity (OR = 1.38, CI = 1.10-1.75) and low birth weight (OR = 1.34, CI = 1.06-1.69) compared with spontaneously conceived different-sex twin pairs. In conclusion, the perinatal outcome of ICSI singleton and twin pregnancies was very similar to that of spontaneously conceived pregnancies in this large cohort study. After excluding like-sex twin pairs, ICSI twins were at increased risk for prematurity, low birth weight and higher perinatal mortality compared with the natural conception comparison group.

Adult↗
PubMed1985

[The selection of organ recipients according to the ABO blood group match. Theory and practice].

The AB0 distribution of the population of Vienna is compared with HLA A, B, C, DR typed transplanted patients (n = 780), kidney donors and potential recipients on the waiting list. The significant differences of AB0 distribution is caused by using group 0 kidney donors for non-0 recipients and donors of groups 0, A and B for group AB recipients. This procedure minimizes the chance of group 0 patients to receive transplants and should be kept in mind by the selection of DR compatible recipients. It is also known that group 0 grafts can develop immune anti A or anti B to the (non-group 0) host, resulting in destruction of the recipient's red cells. The development of such acquired haemolytic anaemia occurs with cyclosporin A medication for immunosuppression.

ABO Blood-Group System↗
PubMed1995

Optometric correlates of Meares-Irlen syndrome: a matched group study.

People who report visual perceptual distortions, typically when reading, that are alleviated by using coloured filters are described as suffering from 'Meares-Irlen Syndrome'. A recent double-masked placebo-controlled trial showed that this condition cannot be solely explained as a placebo effect and that the beneficial filter is idiosyncratic and sometimes needs to be highly specific. Several mechanisms have been suggested for Meares-Irlen Syndrome including ocular motor (binocular and accommodative) anomalies, a sensitivity to patterned stimuli (pattern glare), and a deficit of the transient visual sub-system. We investigated these hypotheses by comparing 16 children, who reported the symptoms described above and who showed a sustained benefit from coloured filters, with 25 control children who came from the same school and were matched for age, reading performance and intelligence. The 'Meares-Irlen Syndrome' group had slightly, but significantly, reduced vergence and accommodative amplitudes and stereo-acuity; they also demonstrated significantly more pattern glare. The two groups did not differ significantly in their visual acuities, refractive error, dissociated or associated heterophoria, AC/A ratio, or ability to perceive 20 Hz flicker. It appears that certain ocular motor factors are correlates of Meares-Irlen Syndrome, rather than the primary underlying cause of the symptoms. The results support the hypothesis that pattern glare may be involved in the mechanism of Meares-Irlen Syndrome.

Accommodation, Ocular↗