Effect of the ownership of dialysis facilities on patients' survival and referral for transplantation

BACKGROUND: More than 200,000 patients with end-stage renal disease undergo dialysis in the United States each year, about two thirds in for-profit centers. Economic pressures, such as the decline in inflation-adjusted Medicare payments for dialysis, may compromise the quality of care. Facilities may also be reluctant to refer patients to be evaluated for transplantation because of the loss of revenues from dialysis after patients receive transplants. It is unknown whether for-profit facilities respond more aggressively than not-for-profit facilities to these financial pressures. Therefore, we examined the effect of for-profit ownership of dialysis facilities on patients' survival and referral for possible transplantation. METHODS: We used data from the U.S. Renal Data System to assemble a nationally representative cohort of patients with end-stage renal disease of recent onset. We followed patients for a minimum of three years and a maximum of six years, until death, placement on the waiting list for a renal transplant, or loss to follow-up, or until May 31, 1996. We used proportional-hazards models to assess the effect of the profit status of the dialysis facility on patients' outcomes and adjusted for differences in sociodemographic, clinical, and facility-level characteristics. RESULTS: Of the 3681 patients who were eligible for inclusion, we included 3569 in the analysis of mortality and 3441 in the analysis of the waiting list. The crude mortality rate per 100 person-years of end-stage renal disease was 21.2 for patients treated in for-profit facilities and 17.1 for patients treated in not-for-profit centers (adjusted relative hazard, 1.20; 95 percent confidence interval, 1.02 to 1.42). The likelihood of being placed on the waiting list for a renal transplant was lower for patients treated at for-profit centers (adjusted relative hazard, 0.74; 95 percent confidence interval, 0.56 to 0.98). CONCLUSIONS: In the United States, for-profit ownership of dialysis facilities, as compared with not-for-profit ownership, is associated with increased mortality and decreased rates of placement on the waiting list for a renal transplant.     

Surgical extraction of subfoveal choroidal new vessels and submacular haemorrhage in age-related macular degeneration: results of a prospective study

· Background: The surgical extraction of subfoveal choroidal new vessels (CNV) is one of several possibilities to treat subfoveal CNV or haemorrhages in age-related macular degeneration (ARMD). · Methods: Prospective study, follow-up 3–6 months. Clinical and angiographic differentiation of three subgroups: (1) subfoveal well-defined CNV (24 eyes); (2) subfoveal ill-defined CNV with or without well-defined components (10 eyes); (3) submacular haemorrhages (20 eyes). · Results: The mean and median visual acuity and the proportion of eyes with ≥20/200 vision increased slightly in group 1 and decreased slightly in group 2; the differences were not significant. Group 3 demonstrated mean improvement but was heterogeneous, depending on the site and type of underlying CNV. The proportion of eyes with 3 or more lines of improvement after 3 months was 35.3% (7/17), 10% (1/10) and 38.9% (7/18) respectively. The proportion of eyes with a loss of 3 or more lines after 3 months was 5.9% (1/17), 20% (2/10) and 5.6% (1/18) respectively. The recurrence rate was 29.2% (7/24), 8.3% (1/11) and 25% (5/20). Intraoperative complications were iatrogenic central tears in 7.3% (4/55), peripheral tears in 14.5% (8/55) and peripheral retinal detachment in 3.6% (2/55). A postoperative retinal detachment was observed in 2 of 55 eyes (3.6%). All these complications could be managed without ill effect. · Conclusion: Subfoveal surgery might perserve remaining retinal function in eyes with well-defined CNV. However, subgroups of the MPS subfoveal laser trials with comparable initial visual acuity demonstrated postoperative functional stabilisation and similar recurrence rates in well-defined CNV. Though selected cases of submacular haemorrhage did profit from surgery, TPA-assisted gas injection will probably be a better alternative. Unfortunately, surgery for ill-defined CNV, found in the vast majority of eyes with exudative ARMD, seems to worsen the natural course. Surgery has to be combined with restoration of Bruch’s membrane before it can become a possible therapeutic option in ARMD. Received: 6 February 1998 Revised version received: 29 April 1998 Accepted: 12 May 1998     

In vivo imaging of the human zonular apparatus with high-resolution ultrasound biomicroscopy

· Background: To investigate the potential of high-resolution ultrasound biomicroscopy (UBM) for studying the zonular apparatus of human beings in vivo. · Methods: Using transducer frequencies of 34 MHz and 50 MHz, criteria were developed to identify transcorneal and transscleral sections that allowed reproducible identification of the different fiber groups of the zonular architecture. For that purpose, 10 volunteers between the ages of 14 and 41 years underwent high-resolution ultrasound biomicroscopy under conditions of consensual far- and near-accommodation. The online video recordings of the respective UBM investigations were afterwards analyzed image by image. Good visibility of zonular fibers was obtained when the ultrasound wave propagation comprised an angle close to 90° with the fiber orientation and when the oscillations of the UBM scan had a strict radial orientation towards the limbus and avoided, simultaneously, the ciliary processes. · Results: In all the volunteers, high-resolution ultrasound biomicroscopy imaged the zonular fiber groups known from histology. In addition, it detected fibers that do not follow the course of the inner ciliary body surface but take a direct route from the ora serrata to the lens. It also demonstrated that fibers that seem to change direction at crossings with other fibers. Under conditions of near-accommodation, the zonular fibers showed signs of relaxation. · Conclusions: High-resolution ultrasound biomicroscopy seems well suited for in vivo investigations of the zonular apparatus and of accommodation in man. The results support the fundamental features of the Helmholtz theory on accommodation. Received: 8 June 1998 Revised version received: 7 September 1998 Accepted: 14 September 1998     

Preoperative infection prophylaxis with 1 % polyvidon-iodine solution based on the example of conjunctival staphylococci

Background: Most germs causing postoperative endophthalmitis derive from the conjunctival bacterial normal flora. Postoperative endophthalmitis is often induced by staphylococcal germs. The application of polyvidone-iodine solution to the conjunctiva is one possibility to reduce potential endophthalmitis-causing bacteria. The aim of this study was to evaluate the effectiveness of 1 % polyvidone-iodine solution concerning the reduction of colonization with staphylococci in the course of intraocular surgery. This is to evaluate the effectiveness of 1 % polyvidone-iodine solution concerning coagulase-negative and positive staphylococci.     

The effect of chronic administration of a synthetic LH-RH analogue intranasally in cryptorchid boys

Eighteen boys with either unilateral or bilateral cryptorchidism were treated with a synthetic LH-RH analogue ("D-Leu 6, Des-Gly-10 LH-RH ethylamide") intranasally. The peptide was dissolved in aqueous solution (25 micrograms in 0,2 ml) and administered in the form of nasal drops. The patients were divided in two groups: in group A, 50 micrograms of the synthetic LH-RH analogue were administered intranasally every 48 h for 36 days; in group B same dose was given every 24 h. Additionally, in 4 cases a LH-RH test prior the trial was performed with the same peptide. The nasal administration resulted in a fivefold increase of LH and of FSH plasma concentration in 30 min and in 60 min, respectively. The endocrine profiles for T, LH and FSH were studied in each group over the treatment period and in group B (same dose was given every 24 h) a significant decrease of the LH and FSH plasma levels could be found. The clinical effect of treatment was same in the both groups. In the whole material 44% had either unilateral or bilateral descent of the testis after the therapy.     

Effect of active immunization to luteinizing-hormone-releasing hormone on the fertility and histoarchitecture of the reproductive organs of male rat

Summary The feasibility of using a vaccine against luteinizing-hormone-releasing factor for supression of pituitary and gonadal functions has been indicated for some time. Antibody production against this low-molecular-weight, naturally occurring decapeptide, however, requires to be coupled to a carrier protein to enhance its immunogenicity. LHRH was coupled to diphtheria toxoid (DT). Adult male Sprague-Dawley rats with a mean basal body weight of 200g were immunized with anti-LHRH-DT (20 g/injection/rat) at four-week intervals. An equal number of unexposed animals served as controls. Six animals were killed every two weeks up the end of the week 43. The vaccination schedule did not have any effect on the gain in body weight, nor was any adverse effect of vaccination observed in the course of the investigations. The pituitary, prostate, epididymis, testes, seminal vesicles, adrenal and thyroid were excised for determination of organ weight and histological examination. The adrenal, pituitary and thyroid showed no remarkable weight changes during the observation period, whereas the weights of the reproductive organs demonstrated significant reductions compared to those of the control group. The histopathology revealed marked to significant changes in the gonads and the accessory sex organs including the prostate. A progressive phase of regeneration of spermatogenesis was evident 98 days after vaccination. Total recovery of spermatogenesis was observed 300 days after vaccination. The mating studies showed the return of fertility 300 days after vaccination. The litters borne were normal. Prostate showed recovery after 154 days of vaccination. Our observations lend strong support to the hypothesis that anti-LHRH vaccine can be effectively used on the management of prostate carcinoma. If the vaccination is given together with a suitable dose of long-acting androgen, contained in an adequate delivery system, the regimen may be used for the regulation of male fertility.     

Frontal dysfunction in schizophrenia – a new electrophysiological classifier for research and clinical applications

We determined whether schizophrenic patients can be reliably classified with electrophysiological tools. We developed a fully computerized classifier based on 5 minutes of EEG recording during an acoustical choice reaction time task (AMDP-module IV). We included factorized variables from the frequency domain and evoked potentials (N100/P200-complex) from central and frontal electrodes, which were preprocessed in a sample of 150 normal subjects prior to classification. We applied discriminant analyses to the electrophysiological data from depressive, schizophrenic and schizotypal subjects, most of them being unmedicated or drug-naive. The classifier was developed on a training set (33 schizophrenics, 49 normals) and tested on an independent sample (32 schizophrenics, 49 normals). A simple three-variable classifier was found to classify schizophrenics and normals in 77% of those tested correctly. Diagnostic specificity of the classifier proved to be low as the inclusion of depressive patients (n= 60) significantly decreased classification power. It was demonstrated that atypical but not typical neuroleptic drugs may influence the classification results. Correctly classified schizophrenics showed significantly more negative symptoms and slower reaction times than those schizophrenics who were misclassified as normals. In contrast, these misclassified schizophrenics showed a non-significant trend for more positive symptoms and shorter reaction times. As the correctly classified schizophrenics showed increased frontally pronounced delta-activity and decreased signal power of the N100/P200 amplitude, it was concluded that these schizophrenics show dysfunction of the frontal lobe. It is proposed that this new classifier can be useful for clinical and research applications when subtyping of schizophrenics with detection of frontal dysfunction as the aim.     

Functional and morphological changes in diabetic macular edema over the course of anti‐vascular endothelial growth factor treatment

Purpose:  To evaluate macular morphology and function in diabetic macular edema (DME) over the course of intravitreal anti‐vascular endothelial growth factor (VEGF) treatment with Ranibizumab. Methods:  A consecutive series of 39 study eyes with centre‐involving DME were included in this study. In all subjects, best‐corrected visual acuity (BCVA) according ETDRS protocol, fluorescein angiography (FA), microperimetric macular sensitivity (MP) and Spectral Domain optical coherence tomography (SD‐OCT) cross‐sectional scans were obtained before treatment and after 3 monthly applied intravitreal Ranibizumab injections. Six different morphological qualities [IS/OS layer integrity, outer nuclear layer (ONL) cysts, ONL cyst size, inner nuclear layer (INL) cysts, blocking phenomenon and subretinal fluid] were graded of each cross‐sectional OCT scan before and over the course of treatment by two experienced graders. Correlation analyses between functional and morphological parameters were obtained. Results:  Mean BCVA increased from 26 ± 14 to 33 ± 13 letters after 3 consecutive monthly applied Ranibizumab injections (p < 0.001). Central retinal thickness (CRT) decreased from 504 ± 144 to 387 ± 122 μm (p < 0.001). Over the course of treatment, IS/OS continuity improved (index: 0.56 ± 0.52 to 0.43 ± 0.49, Z = ?1.415, p = 0.157), ONL cyst prevalence and size decreased significantly (index: 0.61 ± 0.44 to 0.56 ± 0.35, Z = ?3.41, p = 0.001 and 1.75 ± 0.88 to 1.17 ± 1.05, Z = ?4.02, p < 0.001), INL cyst prevalence decreased (index: 0.35 ± 0.52 to 0.28 ± 0.52, Z = ?1.60, p = 0.109), blocking phenomenon did not change significantly (index: 00.12 ± 0.16 to 0.13 ± 0.15, Z = ?0.45, p = 0.656) and subretinal fluid almost disappeared (index: 0.10 ± 0.24 vs. 0.00 ± 0.01, Z = ?2.56, p = 0.011). Correlation analyses revealed highest significant correlations between ONL cyst prevalence and their size and CRT as well as BCVA and MP before treatment and over the course of treatment. Conclusions:  ONL cysts and their size as morphological parameters correlate with retinal function measured with BCVA and microperimetry before and over the course of anti‐VEGF therapy with Ranibizumab in patients with DME.