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W McClellan

Publications and source records attributed to W McClellan.

At least 19 recordsLinked to original sources
PubMed2001

Low body weight is a risk factor for proteinuria in multiracial Southeast Asian pediatric population.

We examined the impact of low birth weight and low current body weight on proteinuria in a cohort of children participating in the pilot study of a nationwide screening program. Two thousand eighty-three children underwent screening examinations, including birth history, anthropometric measures, blood pressure measurements, and urinalysis. On this study, children with proteinuria were found to have significantly lower mean body weights compared with children without proteinuria (38.7 +/- 7.6 versus 42.8 +/- 11.0 kg; P < 0.001). Progressively decreasing body weights were associated with increasing degrees of proteinuria (42.8 +/- 11.0, 38.9 +/- 7.6, and 37.2 +/- 8.5 kg for 0, 30, and 100 mg/dL of protein, respectively; P = 0.05). When examined by multiple logistic regression, low body weight was associated with a 1.8-fold greater risk (95% confidence interval, 1.27 to 2.64; P = 0.0019) for proteinuria after adjusting for potential confounders. There were trends for lower birth weights in children with proteinuria (3,047.6 +/- 445.2 versus 3,175.0 +/- 608.6 g for proteinuric and nonproteinuric groups, respectively; P = 0.275) and a greater prevalence of children with birth weights less than the 25th percentile (31.3% versus 25.0%; P = 0.786). The relationship between low current body weight and proteinuria was not explained by differences in blood pressure. In conclusion, low current body weight had a stronger relationship with proteinuria than low birth weight in this pediatric population. We hypothesize that the effect of low birth weight on renal disease may be significantly enhanced by environmental factors that result in a low current body weight.

Asia↗
PubMed1999

Erythropoietin and iron use in peritoneal dialysis patients. Report from the 1997 HCFA end-stage renal disease core indicators project.

The HCFA ESRD Core Indicators Project is designed to assess several key indicators of care in peritoneal dialysis patients, including anemia management. Information on hematocrit levels, epoetin alfa dosing, estimates of iron stores, and iron therapy as obtained in a national sample of 1,219 peritoneal dialysis patients are described. The average hematocrit was 32.8% +/- 3.8%, and severe anemia (hematocrit < 25%) occurred in 1.4% of PD patients. The mean weekly epoetin alfa dose was 134.6 U/kg. In general, there was an inverse relationship between hematocrit and epoetin alfa doses. Most (83%) of PD patients received iron therapy, with only 8% of patients receiving intravenous iron. The mean serum ferritin was 303 ng/mL, with 64% of patients having a ferritin greater than 100 ng/mL. The mean transferrin saturation was 28%, with 60% of patients having a value of less than 20%. There was an inverse relationship between serum ferritin levels and hematocrit but no relationship between hematocrit and transferrin. It is concluded that there could be improvement in the epoetin alfa and iron management in many patients.

Adolescent↗
PubMed1997

Initial antibiotic management of community acquired pneumonia.

The purpose of this study, conducted by the MAG, the CARE program of the GHA, and the GMCF, is to describe the initial antibiotic management of community acquired pneumonia among hospitalized patients in Georgia and to compare these patterns of care with those recommended by the American Thoracic Society guidelines.

Adult↗
PubMed1996

Relation between geographic variability in kidney stones prevalence and risk factors for stones.

To determine whether geographic variability in rates of kidney stones in the United States was attributable to differences in personal and environmental exposures, the authors examined cross-sectional data that included information on self-reported, physician-diagnosed kidney stones collected from 1,167,009 men and women, aged > or = 30 years, recruited nationally in 1982. Information on risk factors for stones including age, race, education, body mass, hypertension, and diuretic and vitamin C supplement use was obtained by self administered questionnaire. Consumption of milk, coffee, tea, soft drinks, and alcohol was based on food frequency data. Indices of ambient temperature and sunlight level were assigned to subjects based on state of residence. Stones were nearly twice as prevalent in the Southeast as in the Northwest among men and women. Ambient temperature and sunlight indices were independently associated with stones prevalence after controlling for other risk factors for stones. Regional variation was eliminated for men and greatly reduced for women after adjustment for temperature, sunlight, and beverage consumption. Other factors appeared to not contribute to regional variation. These results provide evidence that ambient temperature and sunlight levels are important risk factors for stones and that differences in exposure to temperature and sunlight and beverages may contribute to geographic variability.

Adult↗
PubMed1995

Ethnic differences in the use of peritoneal dialysis as initial treatment for end-stage renal disease.

OBJECTIVE: To evaluate the influence of ethnicity on the use of peritoneal dialysis (PD) as initial treatment for end-stage renal disease (ESRD) after controlling for other patient characteristics. DESIGN: Inception cohort analysis of incident ESRD patients. PATIENTS: All African-American and white patients (N = 10,726) who began treatment for ESRD at dialysis centers in North Carolina, South Carolina, and Georgia and reported to ESRD Network 6 between January 1, 1989, and December 31, 1991. MAIN OUTCOME MEASURE: Odds ratios (ORs) of the association between ethnicity and PD as initial treatment modality. RESULTS: African-American patients were 56% less likely than whites to use PD (OR, 0.44; 95% confidence interval [CI], 0.40 to 0.49). This difference persisted (OR, 0.45; 95% CI, 0.38 to 0.52) after multivariable adjustment for age, education, social support, home ownership, functional status, albumin level, hypertension, history of myocardial infarction, peripheral neuropathy, and comorbid diabetes. CONCLUSIONS: Ethnic differences in initial PD use cannot be explained by many demographic, socioeconomic, and comorbid factors associated with the use of PD as initial treatment for ESRD.

Adult↗
PubMed1994

Facility mortality rates for new end-stage renal disease patients: implications for quality improvement.

End-stage renal disease networks can provide clinicians with valuable information about treatment outcome among their patients compared with those of other providers. These comparisons can help clinicians identify potential quality of care problems and efficiently allocate resources for quality improvement. We have illustrated this application of network information by examining the mortality rates for newly treated end-stage renal disease patients in 161 dialysis facilities in North Carolina, South Carolina, and Georgia. We found that mortality rates were high (an average of 19.2 deaths per 100 years of treatment) and variable (ranging from 0 to 43 deaths per 100 dialysis years). The risk of a patient dying in a facility at the 75th percentile of mortality was 50% higher than that of a patient in a facility at the 25th percentile. Adjusting for patient characteristics (case mix) left considerable variation in the risk of dying among individual dialysis facilities unexplained, suggesting that other treatment center-specific aspects of care contributed to the differences in mortality. After controlling for factors associated with increased mortality, the risk of a patient dying in a facility at the 75th percentile of mortality was 70% greater than that of a patient in a facility at the 25th percentile of mortality. Most facilities, but not all, with the highest unadjusted mortality rates also had the highest adjusted mortality. We conclude that treatment outcome comparisons that have been adjusted to account for case mix among facilities can be provided by network surveillance systems and, when properly understood by providers, might stimulate the search for facility-specific, nonpatient factors that contribute to these outcomes.

Adult↗
PubMed1994

A prospective comparison of methods for determining if cardiovascular disease is a predictor of mortality in dialysis patients.

A random sample of 464 dialysis patients was surveyed between December 1990 and June 1991 to compare methods for determining the relationship between cardiovascular disease (CVD) and mortality. The following three methods were used to identify the prevalence of CVD: standard epidemiologic questionnaires, recall by the patient, and a review of the medical record. The 1-year mortality rate during this prospective study (average follow-up, 17.5 months) was 19%. The measure of prevalent CVD found to be the best predictor of the risk of mortality was the review of the medical record. Specifically, after controlling for the effects on mortality of age, sex, race, cause of renal failure, serum albumin level, and performance status (determined by the Karnofsky score), a patient with a history of angina pectoris documented in the medical record had a relative risk (95% confidence interval) of mortality of 1.8 (1.1 to 2.8), and a patient with peripheral vascular disease recorded in the medical record had a relative risk of 1.6 (1.0 to 2.4). Estimates of CVD obtained from either the questionnaires or patient recall resulted in associations between CVD and mortality that were substantially weaker than those for the medical record. We conclude that at present the medical record is the best source of information for estimating the presence of CVD as a mortality risk factor in dialysis patients. We recommend inclusion of a medical record history of CVD as a mortality case-mix factor when comparing dialysis populations.

Adult↗
PubMed1994

Demographic and geographic variability of kidney stones in the United States.

To characterize demographic and regional variation in kidney stone prevalence in the U.S. we studied two nationwide cross-sectional surveys that included data on self-reported, physician-diagnosed kidney stones, supplementing published data on hospitalizations for stones. The larger study, Cancer Prevention Study II (CPS II), included 1,185,124 men and women, age > or = 30, recruited nationally in 1982, and provides state-specific prevalence estimates. The National Health and Nutrition Examination Survey (NHANES II) was a national probability sample of 25,286 U.S. adults interviewed between 1976 and 1980. Kidney stone prevalence increased with age until age 70, then declined and was higher in men than women and in whites than blacks. Prevalence among Hispanic and Asian men was intermediate between that of whites and blacks. There was a strong, statistically significant regional variability in stone prevalence among U.S. whites. The age-adjusted prevalence increased from north to south, and from west to east. The contrast in state-specific prevalence was greatest between men in North Carolina (prevalence = 14.9; 95% confidence interval = 14.2 to 15.7) and North Dakota (5.6; 4.7 to 6.4), and between women in South Carolina (6.4; 5.8 to 6.9) and South Dakota (2.4; 1.9 to 2.9). The marked variations in kidney stone prevalence by age, gender, race, and geographic location may provide clues to their etiology and prevention.

Adult↗
PubMed1994

Race and the risk of peritonitis: an analysis of factors associated with the initial episode.

To study how clinical characteristics influence the risk of peritonitis in African American patients with end-stage renal disease treated with continuous ambulatory peritoneal dialysis (CAPD), we examined the risk of developing a first episode of peritonitis among 1,595 new dialysis patients initially treated by CAPD over a two year period in North Carolina, South Carolina, and Georgia (Network 6). Characteristics examined were demographic and socioeconomic factors, functional status, serum albumin and comorbid conditions. There were 538 initial episodes of peritonitis during an average of 8.8 patient months of follow-up; the time to peritonitis for the entire cohort was 26 months. Factors found to be independently associated with a risk for peritonitis were student status (Odds Ratio and 95% Confidence Interval = 2.4; 1.4 to 4.3), rental housing (1.2; 1.0 to 1.5), and substance abuse (1.9; 1.1 to 3.2). African Americans were 60% more likely to have an initial episode of peritonitis during follow-up than whites (1.6; 1.3 to 1.8). The time to the initial episode was 21 months for African Americans versus 32 months for whites (P < 0.001). Even after adjusting for other factors, African Americans were significantly more likely to develop peritonitis (1.5; 1.2 to 1.8). Thus, the increased risk of peritonitis of African American patients treated by CAPD is independent of other demographic, socioeconomic and comorbid characteristics.

Adult↗
PubMed1993

Hypertensive end-stage renal disease in blacks: the role of end-stage renal disease surveillance.

The end-stage renal disease (ESRD) networks and the United States Renal Data System recently have described the epidemiology of ESRD and broadened our appreciation of the impact of ESRD in the United States. This surveillance system also can be used to study the occurrence and control of ESRD. Among the epidemiologic study designs available to conduct research on the etiology of renal failure, case-control studies are uniquely suited for this purpose. The case of hypertensive ESRD illustrates this concept; risk factors for hypertensive ESRD, as a hypothetical exposure in case-control studies, are briefly described. Case-control studies are an efficient and readily used means to study causes of renal failure.

Black People↗
PubMed1992

Race and sex differences in the identification of candidates for renal transplantation.

The availability of renal transplantation to individuals with end-stage renal disease (ESRD) is an issue of considerable concern. The role of age, race, sex, socioeconomic status, illness severity, and comorbidity in determining access to this therapy remains unclear. We examined the influence of these factors on transplant candidacy in 8,315 patients receiving dialysis treatment for ESRD in North Carolina, South Carolina, and Georgia. We found important race-sex differences in the likelihood of being identified as a transplant candidate. These differences persisted after adjustment for other patient characteristics, including illness severity and certain comorbid conditions. Characteristics found to be positively associated with candidacy included age less than 30 years (P less than 0.00001), living with a spouse and children (P = 0.004), and employment status (P = 0.006). Characteristics and comorbid conditions that were negatively associated with candidacy included 8 years or less of formal education (P = 0.001), cancer (P = 0.0006), visual impairment (P = 0.006), congestive heart failure (P = 0.008), and peripheral vascular disease (P = 0.01). Compared with white males, after adjustment for these factors, the likelihood (95% confidence interval) of being identified as a transplant candidate was: white females, 0.88 (0.65 to 1.18); black males, 0.77 (0.59 to 0.99); and black females, 0.66 (0.51 to 0.87). We conclude that although socioeconomic and medical factors are strongly associated with transplant candidacy, these associations do not adequately explain the observed race-sex differences in transplant candidacy status.

Adolescent↗
PubMed1990

The epidemiology of end-stage renal disease in Georgia.

We have examined the incidence of end-stage renal disease (ESRD) in Georgia in 1986 and 1987. We found high age-sex-race specific and total incidence rates compared to rates reported for other U.S. populations. Cause-specific and total ESRD incidence rates were significantly higher among blacks as compared to whites. In both races, the majority of new cases of ESRD occurring in Georgia during 1986 and 1987 can be attributed to diabetes or hypertension. Total ESRD rates were not uniform throughout the state; counties of the Coastal Plain (South) were significantly more likely to have higher rates than counties in the Piedmont Region (North). These patterns of ESRD in Georgia have implications for possible prevention efforts.

Adult↗
PubMed1989

Correlates of drug therapy of diastolic blood pressure between 80-89 mm Hg by physicians in the community.

We have conducted a random probability survey of primary care physicians (n = 477) to examine the factors which might influence the level of diastolic blood pressure (DBP) felt by physicians to warrant antihypertensive drug therapy in young adults. Of the responding physicians, 18.4% reported treating young adults who had a DBP of less than 90 mm Hg. This practice was correlated with physician opinions about the efficacy of hypertension treatment and the reported influence of pharmaceutical representatives on physician practice. We conclude that reported therapy of DBP less than 90 mm Hg in young adults is highly prevalent. Such therapy is correlated with physician opinions as well as the perceived influence of pharmaceutical sources of information.

Adult↗