Elizabeth A. Mauger

Comparative Mortality Risks of Chronic Dialysis and Cadaveric Transplantation in Black End-Stage Renal Disease Patients

In view of the relatively low mortality risk on dialysis and the high risk of allograft loss among black compared with white end-stage renal disease (ESRD) patients, we studied the relative mortality risks of all black renal transplant candidates in Michigan from 1984 to 1989. There were 770 black ESRD patients followed from wait-listing for cadaveric (CAD) kidney transplantation until the time of transplantation, death, or December 31, 1989. The time on dialysis prior to wait-listing exceeded 1 year in 24% of these patients. Black diabetic patients on the waiting list have more than twofold relative mortality risk (RR) compared with nondiabetic individuals (RR = 2.73, P < 0.001) while the RR by diabetes status among CAD transplant recipients was small. Overall, CAD transplantation was associated with elevated risk of mortality in the first month posttransplantation (RR = 3.39, P < 0.03). Cadaveric donor transplant and wait-listed dialysis patients have equal death rates 112 days after transplantation. Thereafter, death rates were lower for transplant recipients compared with transplant candidates on dialysis. One year after transplantation, CAD transplant recipients on the average have approximately half the risk of death compared with dialysis patients who remain on the waiting list (RR = 0.49, P < 0.03). The cumulative survival probabilities are superior in transplant recipients just beyond 1 year after transplantation. Therefore, CAD transplantation in black ESRD patients is associated with a high risk of mortality in the early period after transplantation. Beyond 1 year, black transplant recipients have a substantial survival advantage over corresponding dialysis patients on the waiting list.

Association of gender and access to cadaveric renal transplantation

Previous studies have revealed that females are less likely than males to receive a renal transplant, the most successful form of treatment of end-stage renal disease (ESRD). The purpose of this study was to determine whether the barrier is to inclusion on the transplant waiting list or to transplantation after being placed on the transplant waiting list. An existing data set was used that included data from the Michigan Kidney Registry, supplemented with data received from the Organ Procurement Agency of Michigan. White and black patients less than 65 years of age and starting ESRD treatment between January 1, 1984, and December 31, 1989, were included. Cox proportional hazards models were used to determine the effect of gender on (1) time to transplantation among all ESRD patients, (2) time from diagnosis of ESRD to inclusion on the transplant waiting list among all ESRD patients, and (3) time from inclusion on the waiting list to transplantation among those patients on the waiting list. Patients were censored at the time of living-related transplantation or death, and were monitored until December 31, 1989. In all, 5,026 incident ESRD patients were included in the study (44.3% female). Of these, 1,626 patients were included on the waiting list (40.1% female); 823 of these received a transplant (37.7% female). Adjusting for age, race, and diagnosis, females were 25% less likely to receive a cadaveric transplant than males (female to male relative rate ratio [RR], 0.75; P < 0.001). Females with ESRD aged 46 to 55 years and 56 to 65 years were 33% (RR, 0.67; P < 0.001) and 29% (RR, 0.71; P < 0.05) less likely to be included on the transplant waiting list, respectively, than their male counterparts. There was no difference in the rate of wait list inclusion among ESRD patients younger than 46 years. Females with ESRD who were included on the transplant waiting list were 26% (RR, 0.74; P < 0.001) less likely to receive a transplant than males on the waiting list. These results indicate that females are both less likely to be on the transplant waiting list (ages over 45 years) and, once on the list, less likely to receive a transplant (all ages) than males. Further study is necessary to determine the factors contributing to these important barriers to transplantation among females with ESRD.

Occupational radiation exposure to interventional radiologists: a prospective study.

This study investigates the occupational radiation dose to interventional radiologists and the operator-controlled factors that may affect dose. Thirty interventional radiologists wore radiation badges over and under lead aprons for 2 months and answered a questionnaire. The relationships between dose and caseload, case mix, experience, optional fluoroscopy features, lead apron type, and additional lead shielding were evaluated. Mean projected yearly dose (PYD) over lead was 49.1 mSv (1 mSv = 100 mrem) but was 66.6 mSv for persons performing 1,000 or more cases per year (P = .027). Mean PYD under lead was 0.9 mSv but was 1.3 mSv for persons with 0.5-mm lead coverage and 0.4 mSv for those with 1.0-mm lead coverage (P = .002). No other significant correlation was found. Conclusions are that caseload and apron thickness are the primary determinants of total body dose, that over-lead dose is high enough to warrant additional lead shielding for the head and neck, and that a double-thickness apron lowers under-lead dose by two-thirds. The large difference between under-lead and over-lead doses suggests that use of a collar badge alone for monitoring purposes is not predictive of total-body effective dose for this group of radiation workers.

Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation.

Objective: Caffeine consumption has been proposed as a risk factor for bone loss in postmenopausal women. Past epidemiologic studies on caffeine and bone have been confounded by covariates including cigarette and alcohol use, differing levels of physical activity and hormone replacement therapy. The purpose of the study was to use a longitudinal design to determine the relationship between habitual dietary caffeine intake and postmenopausal bone status. Methods: Data were collected at two time points separated by two years; 138 women with little or no exposure to tobacco or to drugs known to affect bone status were seen at Visit 1, and 112 returned for Visit 2. Ninety-two of these subjects had received no drugs known to affect bone status over the two-year interval and were kept in the sample. Nutrient and caffeine intake were assessed from three-day diet records. Bone measurements were made by dual energy x-ray absorptiometry (DXA). Results: Correlation analyses indicated no association between dietary caffeine intake and total body or femoral neck bone density or bone mass. Similarly, no associations were found between caffeine consumption and longitudinal changes in total body or femoral neck bone measurements. These results held true both with and without statistical adjustment for calcium intake. Conclusions: This study does not support the idea that caffeine is a risk factor for bone loss in healthy postmenopausal women.

Effect of topical nasal azelastine on the symptoms of rhinitis, sleep, and daytime somnolence in perennial allergic rhinitis.

BACKGROUND Recent data suggested that daytime somnolence in patients with allergic rhinitis was secondary to disrupted sleep caused by nasal congestion. Medications, which decreased congestion, would be expected to improve sleep and daytime somnolence. Previously, we demonstrated that nasal steroids improved all three symptoms. The effect of topical nasal antihistamines on these symptoms has yet to be studied. OBJECTIVE The objective of this 8-week, double-blind, placebo-controlled study was to determine whether topical nasal azelastine was effective at decreasing congestion, daytime somnolence, and improving sleep. METHODS We recruited 24 subjects with perennial allergic rhinitis and randomized them in a double-blinded, crossover fashion, to receive placebo or azelastine two sprays BID, using Balaams design. Questionnaires, daily diary, and Epworth Sleepiness Scale were used as tools. The last 2 weeks of each 4-week treatment period were summarized, scored, and compared by PROC MIXED in SAS. RESULTS The analysis of the Rhinitis Severity Score showed significant improvement only of rhinorrhea in the azelastine group (P = .03). The symptom severity of nasal congestion and daytime somnolence was not significantly different between placebo and azelastine. Subjects considered azelastine effective at improving their sleep (P = .04), but daytime somnolence (P = .06) and congestion (P = .09) were not statistically improved. CONCLUSION Azelastine is effective in reducing rhinorrhea and improving sleep quality. We were unable to demonstrate that azelastine can significantly reduce the severity of congestion or daytime somnolence.

Dietary caffeine intake is not correlated with adolescent bone gain

OBJECTIVE This study was conducted to determine whether dietary caffeine consumed by American white females between ages 12 to 18 affects total body bone mineral gain during ages 12 to 18 or affects hip bone density measured at age 18. METHODS The Penn State Young Womens Health Study is a longitudinal investigation of bone, endocrine and cardiovascular health in non-Hispanic, white, teenage women. Nutrient and food group intakes were obtained by averaging over 6 years of prospective diet records. The cohort, as of age 18, (n = 81) was separated into three subgroups according to mean daily caffeine intake averaged across ages 12 to 18. Group I (n = 37) consumed less than 25 mg caffeine per day; Group II (n = 33) consumed 25 to 50 mg caffeine per day; and Group III (n = 11) consumed greater than 50 mg caffeine per day. The group mean daily caffeine intakes (SD) were Group I = 14 (6) mg/day; Group II = 35 (7) mg/day; Group III = 77 (27) mg/day. Total body bone gain and hip bone density were determined by dual energy x-ray absorptiometry (DXA). RESULTS There were no significant differences among the three caffeine intake groups for total body bone mineral gain during the ages 12 to 18 or of hip bone density at age 18. The low caffeine intake group consumed more milk (and therefore more calcium) and more fruit per day than did the other two groups. Group III, the highest caffeine intake group, consumed more sugar per day than did the other two groups. The observed differences in nutrient and food intakes among the three groups were not associated with any differences in anthropometric measurements or bone gain among the three groups. CONCLUSION These findings indicate that dietary caffeine intake at levels presently consumed by American white, teenage women is not correlated with adolescent total bone mineral gain or hip bone density at age 18.

Summarizing methacholine challenges in clinical research.

In clinical trials in asthma, airway reactivity is commonly assessed by performing a methacholine challenge. Airway reactivity is thought to vary in proportion to asthma severity, and methacholine causes the airways of asthma subjects to constrict, thus lowering forced expiratory volume in 1 second (FEV(1)). A dose-response curve is obtained for each subject who meets standardized eligibility requirements to proceed with a methacholine challenge. When data from a methacholine challenge are used as an outcome variable in analysis, a univariate measure called the PC(20), the concentration of methacholine needed to produce a 20% fall in FEV(1) from baseline, is typically used to summarize the dose-response curve. Questions that arise regarding data generated from the methacholine challenge include: how to express data that do not yield a PC(20) value; whether PC(20) actually represents the best way to capture airway activity as expressed in a methacholine challenge; and whether the baseline FEV(1) is defined appropriately in calculation of PC(20). The impact of these issues on the statistical analysis of methacholine challenge data is described in this article. Some adjustments to the usual estimates of PC(20) and parametric modeling of the entire dose-response curve are proposed as alternatives that address some of the shortcomings of PC(20).