Polypharmacy and mortality association by chronic kidney disease status: The REasons for Geographic And Racial Differences in Stroke Study

Many Americans take multiple medications simultaneously (polypharmacy). Polypharmacy's effects on mortality are uncertain. We endeavored to assess the association between polypharmacy and mortality in a large U.S. cohort and examine potential effect modification by chronic kidney disease (CKD) status. The REasons for Geographic And Racial Differences in Stroke cohort data (n = 29 627, comprised of U.S. black and white adults) were used. During a baseline home visit, pill bottle inspections ascertained medications used in the previous 2 weeks. Polypharmacy status (major [≥8 ingredients], minor [6-7 ingredients], and none [0-5 ingredients]) was determined by counting the total number of generic ingredients. Cox models (time-on-study and age-time-scale methods) assessed the association between polypharmacy and mortality. Alternative models examined confounding by indication and possible effect modification by CKD. Over 4.9 years median follow-up, 2538 deaths were observed. Major polypharmacy was associated with increased mortality in all models, with hazard ratios and 95% confidence intervals ranging from 1.22 (1.07-1.40) to 2.35 (2.15-2.56), with weaker associations in more adjusted models. Minor polypharmacy was associated with mortality in some, but not all, models. The polypharmacy-mortality association did not differ by CKD status. While residual confounding by indication cannot be excluded, in this large American cohort, major polypharmacy was consistently associated with mortality.

Serum 25-hydroxyvitamin D level and kidney function decline in a Swiss general adult population

BACKGROUND AND OBJECTIVES

Molecular evidence suggests that levels of vitamin D are associated with kidney function loss. Still, population-based studies are limited and few have considered the potential confounding effect of baseline kidney function. This study evaluated the association of serum 25-hydroxyvitamin D with change in eGFR, rapid eGFR decline, and incidence of CKD and albuminuria.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Baseline (2003-2006) and 5.5-year follow-up data from a Swiss adult general population were used to evaluate the association of serum 25-hydroxyvitamin D with change in eGFR, rapid eGFR decline (annual loss >3 ml/min per 1.73 m(2)), and incidence of CKD and albuminuria. Serum 25-hydroxyvitamin D was measured at baseline using liquid chromatography-tandem mass spectrometry. eGFR and albuminuria were collected at baseline and follow-up. Multivariate linear and logistic regression models were used considering potential confounding factors.

RESULTS

Among the 4280 people included in the analysis, the mean±SD annual eGFR change was -0.57±1.78 ml/min per 1.73 m(2), and 287 (6.7%) participants presented rapid eGFR decline. Before adjustment for baseline eGFR, baseline 25-hydroxyvitamin D level was associated with both mean annual eGFR change and risk of rapid eGFR decline, independently of baseline albuminuria. Once adjusted for baseline eGFR, associations were no longer significant. For every 10 ng/ml higher baseline 25-hydroxyvitamin D, the adjusted mean annual eGFR change was -0.005 ml/min per 1.73 m(2) (95% confidence interval, -0.063 to 0.053; P=0.87) and the risk of rapid eGFR decline was null (odds ratio, 0.93; 95% confidence interval, 0.79 to 1.08; P=0.33). Baseline 25-hydroxyvitamin D level was not associated with incidence of CKD or albuminuria.

CONCLUSIONS

The association of 25-hydroxyvitamin D with eGFR decline is confounded by baseline eGFR. Sufficient 25-hydroxyvitamin D levels do not seem to protect from eGFR decline independently from baseline eGFR.

Geographic region and racial variations in polypharmacy in the United States

PURPOSE

Medications can have unintended effects. High medication use populations may benefit from increased regimen oversight. Limited knowledge exists concerning racial and regional polypharmacy variation. We estimated total medication distributions (excluding supplements) of American black and white adults and assessed racial and regional polypharmacy variation.

METHODS

REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort data (n = 30,239 U.S. blacks and whites aged ≥45 years) were analyzed. Home pill bottle inspections assessed the last two weeks' medications. Polypharmacy (≥8 medications) was determined by summing prescription and/or over-the-counter ingredients. Population-weighted logistic regression assessed polypharmacy's association with census region, race, and sex.

RESULTS

The mean ingredient number was 4.12 (standard error = 0.039), with 15.7% of REGARDS using 8 ingredients or more. In crude comparisons, women used more medications than men, and blacks and whites reported similar mean ingredients. A cross-sectional, logistic model adjusting for demographics, socioeconomics, and comorbidities showed increased polypharmacy prevalence in whites versus blacks (OR [95% CI]: 0.63, [0.55-0.72]), women (1.94 [1.68-2.23]), and Southerners (broadly Southeasterners and Texans; 1.48 [1.17-1.87]) versus Northeasterners (broadly New England and upper Mid-Atlantic). Possible limitations include polypharmacy misclassification and model misspecification.

CONCLUSION

Polypharmacy is common. Race and geography are associated with polypharmacy variation. Further study of underlying factors explaining these differences is warranted.

Sustained Reduction in the Clinical Incidence of Methicillin-Resistant Staphylococcus aureus Colonization or Infection Associated with a Multifaceted Infection Control Intervention

Objective.

To assess the impact and sustainability of a multifaceted intervention to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission implemented in 3 chronologically overlapping phases at 1 hospital.

Design.

Interrupted time-series analyses.

Setting.

A Veterans Affairs hospital in the northeastern United States.

Patients and Participants.

Individuals admitted to acute care units from October 1, 1999, through September 30, 2008. To calculate the monthly clinical incidence of MRSA colonization or infection, the number of MRSA-positive cultures obtained from a clinical site more than 48 hours after admission among patients with no MRSA-positive clinical cultures during the previous year was divided by patient-days at risk. Secondary outcomes included clinical incidence of methicillin-sensitive S. aureus colonization or infection and incidence of MRSA bloodstream infections.

Interventions.

The intervention—implemented in a surgical ward beginning October 2001, in a surgical intensive care unit beginning October 2003, and in all acute care units beginning July 2005—included systems and behavior change strategies to increase adherence to infection control precautions (eg, hand hygiene and active surveillance culturing for MRSA).

Results.

Hospital-wide, the clinical incidence of MRSA colonization or infection decreased after initiation of the intervention in 2001, compared with the period before intervention (P = .002), and decreased by 61% (P < .001) in the 7-year postintervention period. In the postintervention period, the hospital-wide incidence of MRSA bloodstream infection decreased by 50% (P = .02), and the proportion of S. aureus isolates that were methicillin resistant decreased by 30% (P < .001).

Conclusions.

Sustained decreases in hospital-wide clinical incidence of MRSA colonization or infection, incidence of MRSA bloodstream infection, and proportion of S. aureus isolates resistant to methicillin followed implementation of a multifaceted prevention program at one Veterans Affairs hospital. Findings suggest that interventions designed to prevent transmission can impact endemic antimicrobial resistance problems.

Actor-partner effects associated with experiencing intimate partner violence or coercion among male couples enrolled in an HIV prevention trial

Background

Intimate partner violence (IPV) and coercion have been associated with negative health outcomes, including increased HIV risk behaviors, among men who have sex with men (MSM). This is the first study to describe the prevalence and factors associated with experiencing IPV or coercion among US MSM dyads using the actor-partner interdependence model (APIM), an analytic framework to describe interdependent outcomes within dyads.

Methods

Among MSM couples enrolled as dyads in an HIV prevention randomized controlled trial (RCT), two outcomes are examined in this cross-sectional analysis: 1) the actor experiencing physical or sexual IPV from the study partner in the past 3-months and 2) the actor feeling coerced to participate in the RCT by the study partner. Two multilevel APIM logistic regression models evaluated the association between each outcome and actor, partner, and dyad-level factors.

Results

Of 190 individuals (95 MSM couples), 14 reported experiencing physical or sexual IPV from their study partner in the past 3 months (7.3%) and 12 reported feeling coerced to participate in the RCT by their study partner (6.3%). Results of multivariate APIM analyses indicated that reporting experienced IPV was associated (p < 0.1) with non-Black/African American actor race, lower actor education, and lower partner education. Reporting experienced coercion was associated (p < 0.1) with younger actor age and lower partner education.

Conclusions

These findings from an HIV prevention RCT for MSM show considerable levels of IPV experienced in the past 3-months and coercion to participate in the research study, indicating the need for screening tools and support services for these behaviors. The identification of factors associated with IPV and coercion demonstrate the importance of considering actor and partner effects, as well as dyadic-level effects, to improve development of screening tools and support services for these outcomes.

Impact of long-term contraceptive promotion on incident pregnancy: a randomized controlled trial among HIV-positive couples in Lusaka, Zambia

OBJECTIVES

To evaluate the impact of family planning promotion on incident pregnancy in a combined effort to address Prongs 1 and 2 of prevention of mother-to-child transmission of HIV.

DESIGN

We conducted a factorial randomized controlled trial of 2 video-based interventions.

METHODS

"Methods" and "Motivational" messages promoted long-term contraceptive use among 1060 couples with HIV in Lusaka, Zambia.

RESULTS

Among couples not using contraception before randomization (n = 782), the video interventions had no impact on incident pregnancy. Among baseline contraceptive users, viewing the "Methods video" which focused on the intrauterine device and contraceptive implant was associated with a significantly lower pregnancy incidence [hazard ratio (HR) = 0.38; 95% confidence interval (CI): 0.19 to 0.75] relative to those viewing control and/or motivational videos. The effect was strongest in concordant positive couples (HR = 0.22; 95% CI: 0.08 to 0.58) and couples with HIV-positive women (HR = 0.23; 95% CI: 0.09 to 0.55).

CONCLUSIONS

The "Methods video" intervention was previously shown to increase uptake of long-acting contraception and to prompt a shift from daily oral contraceptives to quarterly injectables and long-acting methods such as the intrauterine device and implant. Follow-up confirms sustained intervention impact on pregnancy incidence among baseline contraceptive users, in particular couples with HIV-positive women. Further work is needed to identify effective interventions to promote long-acting contraception among couples who have not yet adopted modern methods.

Cooking fuel type, household ventilation, and the risk of acute lower respiratory illness in urban Bangladeshi children: a longitudinal study

Acute lower respiratory illnesses (ALRI) are the leading cause of death among children <5 years. Studies have found that biomass cooking fuels are an important risk factor for ALRI. However, few studies have evaluated the influence of natural household ventilation indicators on ALRI. The purpose of this study was to assess the association between cooking fuel, natural household ventilation, and ALRI. During October 17, 2004-September 30, 2005, children <5 years living in a low-income neighborhood of Dhaka, Bangladesh, were assessed weekly for ALRI and surveyed quarterly about biomass fuel use, electric fan ownership, and natural household ventilation (windows, ventilation grates, and presence of a gap between the wall and ceiling). Bivariate and multivariate analyses were performed using generalized estimating equations. Six thousand and seventy-nine children <5 years enrolled during the study period (99% participation) experienced 1291 ALRI. In the multivariate model, ≥2 windows [OR = 0.75, 95% CI = (0.58, 0.96)], ventilation grates [OR = 0.80, 95% CI = (0.65, 0.98)], and not owning an electric fan [OR = 1.50, 95% CI = (1.21, 1.88)] were associated with ALRI; gap presence and using biomass fuels were not associated with ALRI. Structural factors that might improve household air circulation and exchange were associated with decreased ALRI risk. Improved natural ventilation might reduce ALRI among children in low-income families.

PRACTICAL IMPLICATIONS

The World Health Organization has stated that controlling pneumonia is a priority for achieving the fourth Millennium Development Goal, which calls for a two-third reduction in mortality of children <5 years old compared to the 1990 baseline. Our study represents an important finding of a modifiable risk factor that might decrease the burden of respiratory illness among children living in Bangladesh and other low-income settings similar to our study site. We found that the existence of at least two windows in the child's sleeping room was associated with a 25% decreased ALRI risk. Increasing available natural ventilation within the household in similar settings has the potential to reduce childhood mortality because of acute lower respiratory illnesses.

Promotion of couples' voluntary HIV counselling and testing in Lusaka, Zambia by influence network leaders and agents

OBJECTIVES

Hypothesising that couples' voluntary counselling and testing (CVCT) promotions can increase CVCT uptake, this study identified predictors of successful CVCT promotion in Lusaka, Zambia.

DESIGN

Cohort study.

SETTING

Lusaka, Zambia.

PARTICIPANTS

68 influential network leaders (INLs) identified 320 agents (INAs) who delivered 29 119 CVCT invitations to heterosexual couples.

INTERVENTION

The CVCT promotional model used INLs who identified INAs, who in turn conducted community-based promotion and distribution of CVCT invitations in two neighbourhoods over 18 months, with a mobile unit in one neighbourhood crossing over to the other mid-way through.

PRIMARY OUTCOME

The primary outcome of interest was couple testing (yes/no) after receipt of a CVCT invitation. INA, couple and invitation characteristics predictive of couples' testing were evaluated accounting for two-level clustering.

RESULTS

INAs delivered invitations resulting in 1727 couples testing (6% success rate). In multivariate analyses, INA characteristics significantly predictive of CVCT uptake included promoting in community-based (adjusted OR (aOR)=1.3; 95% CI 1.0 to 1.8) or health (aOR=1.5; 95% CI 1.2 to 2.0) networks versus private networks; being employed in the sales/service industry (aOR=1.5; 95% CI 1.0 to 2.1) versus unskilled manual labour; owning a home (aOR=0.7; 95% CI 0.6 to 0.9) versus not; and having tested for HIV with a partner (aOR=1.4; 95% CI 1.1 to 1.7) or alone (aOR=1.3; 95% CI 1.0 to 1.6) versus never having tested. Cohabiting couples were more likely to test (aOR=1.4; 95% CI 1.2 to 1.6) than non-cohabiting couples. Context characteristics predictive of CVCT uptake included inviting couples (aOR=1.2; 95% CI 1.0 to 1.4) versus individuals; the woman (aOR=1.6; 95% CI 1.2 to 2.2) or couple (aOR=1.4; 95% CI 1.0 to 1.8) initiating contact versus the INA; the couple being socially acquainted with the INA (aOR=1.6; 95% CI 1.4 to 1.9) versus having just met; home invitation delivery (aOR=1.3; 95% CI 1.1 to 1.5) versus elsewhere; and easy invitation delivery (aOR=1.8; 95% CI 1.4 to 2.2) versus difficult as reported by the INA.

CONCLUSIONS

This study demonstrated the ability of influential people to promote CVCT and identified agent, couple and context-level factors associated with CVCT uptake in Lusaka, Zambia. We encourage the development of CVCT promotions in other sub-Saharan African countries to support sustained CVCT dissemination.

Detection of pelvic inflammatory disease: development of an automated case-finding algorithm using administrative data

ICD-9 codes are conventionally used to identify pelvic inflammatory disease (PID) from administrative data for surveillance purposes. This approach may include non-PID cases. To refine PID case identification among women with ICD-9 codes suggestive of PID, a case-finding algorithm was developed using additional variables. Potential PID cases were identified among women aged 15-44 years at Group Health (GH) and Kaiser Permanente Colorado (KPCO) and verified by medical record review. A classification and regression tree analysis was used to develop the algorithm at GH; validation occurred at KPCO. The positive predictive value (PPV) for using ICD-9 codes alone to identify clinical PID cases was 79%. The algorithm identified PID appropriate treatment and age 15-25 years as predictors. Algorithm sensitivity (GH = 96.4%; KPCO = 90.3%) and PPV (GH = 86.9%; KPCO = 84.5%) were high, but specificity was poor (GH = 45.9%; KPCO = 37.0%). In GH, the algorithm offered a practical alternative to medical record review to further improve PID case identification.

Chlamydia positivity trends among women attending family planning clinics: United States, 2004-2008

BACKGROUND

Annual chlamydia screening is recommended for all sexually active women aged <25 years. Substantial limitations exist in ascertaining chlamydia trends. Reported case rates have increased likely due to increased screening and improved test technology. Other data suggest that prevalence has decreased.

METHODS

Data from the Infertility Prevention Project (IPP), a national chlamydia screening program, were used to assess trends in chlamydia positivity from 2004 to 2008 among women aged 15 to 24 years who were tested in family planning clinics reporting data to IPP. Using the clinic as the unit of analysis, a correlated, longitudinal data analysis with a random intercept was conducted among clinics reporting ≥3 years of data during the analysis timeframe. Sensitivity analyses were performed to address the impact of various clinic participation levels in addition to the assessment of various correlation structures.

RESULTS

Over 5 million chlamydia tests were reported to IPP family planning clinics from 2004 to 2008. A majority of tests were conducted among white women (clinic-specific mean: 63.2%, interquartile range: 37.6%-91.5%); the clinic-specific mean percent of tests conducted among black women was 17.9% (interquartile range: 0.8%-25.7%). Overall chlamydia positivity from 2004 to 2008 was 7.0%. The odds ratio associated with a single year change (1.00; 95% confidence interval: 0.99, 1.00) suggested that chlamydia positivity did not change from 2004 to 2008, after controlling for clinic-specific population factors (age, race, test usage, and geography).

CONCLUSIONS

Findings support previous analyses suggesting that chlamydia prevalence is not increasing despite apparent increasing rates based on case reports.

Neighborhood poverty and racial disparities in kidney transplant waitlisting

Racial disparities persist in the United States renal transplantation process. Previous studies suggest that the distance between a patient's residence and the transplant facility may associate with disparities in transplant waitlisting. We examined this possibility in a cohort study using data for incident, adult ESRD patients (1998 to 2002) from the ESRD Network 6, which includes Georgia, North Carolina, and South Carolina. We linked data with the United Network for Organ Sharing (UNOS) transplant registry through 2005 and with the 2000 U.S. Census geographic data. Of the 35,346 subjects included in the analysis, 12% were waitlisted, 57% were black, 50% were men, 20% were impoverished, 45% had diabetes as the primary etiology of ESRD, and 73% had two or more comorbidities. The median distance from patient residence to the nearest transplant center was 48 mi. After controlling for multiple covariates, distance from patient residence to transplant center did not predict placement on the transplant waitlist. In contrast, race, neighborhood poverty, gender, age, diabetes, hypertension, body mass index, albumin, and the use of erythropoietin at dialysis initiation was associated with waitlisting. As neighborhood poverty increased, the likelihood of waitlisting decreased for blacks compared with whites in each poverty category; in the poorest neighborhoods, blacks were 57% less likely to be waitlisted than whites. This study suggests that improving the allocation of kidneys may require a focus on poor communities.

Reductions in the energy content of meals served in the Chilean National Nursery School Council Program did not consistently decrease obesity among beneficiaries

In 2001, the Chilean National Nursery Schools Council Program reduced by 10% the energy content (approximately 418.7 kJ) of meals served to children to reduce obesity. We assessed the impact of this measure on obesity and stunting among beneficiaries 2-5 y old. The energy reduction was staggered over 3 y, allowing for a quasi-experimental design involving early (2001), mid (2002), and late (2003) intervention groups. Routine anthropometric measurements (approximately 64,000/y) taken from 1996-2005 were obtained from registries; obesity (BMI-for-age Z-score > or = 2 SD) and stunting (height-for-age Z-score < or = 2 SD) were defined using the 2006 growth standards. Segmented regression analyses were conducted by intervention group to contrast pre- and postintervention trends. Overall, obesity was high (15.9%), with levels consistently higher in fall and winter as reported in other studies. Preintervention obesity trends increased in the early group (P = 0.001) but decreased in the late intervention group (P = 0.02). The impact of the energy reduction on obesity was inconsistent, with reductions in the early group (P < 0.01) but with no change in mid and late intervention groups (P > 0.05). Stunting prevalence was almost as low as in the growth standard (3.2 vs. 2.3%) and decreased preintervention in all groups (P < 0.05). Stunting prevalence increased postintervention (P < 0.05) in all but the late intervention group, where there was no change. Despite a robust design and the ability to detect small seasonal changes in obesity, our analyses showed that the 10% energy reduction did not consistently decrease obesity. The intervention may have slowed improvements in linear growth, but concern is tempered by the near absence of growth failure.

Neighborhood poverty and racial differences in ESRD incidence

Poverty is associated with increased risk of ESRD, but its contribution to observed racial differences in disease incidence is not well-defined. To explore the contribution of neighborhood poverty to racial disparity in ESRD incidence, we analyzed a combination of US Census and ESRD Network 6 data comprising 34,767 patients that initiated dialysis in Georgia, North Carolina, or South Carolina between January 1998 and December 2002. Census tracts were used as the geographic units of analysis, and the proportion of the census tract population living below the poverty level was our measure of neighborhood poverty. Incident ESRD rates were modeled using two-level Poisson regression, where race, age and gender were individual covariates (level 1), and census tract poverty was a neighborhood covariate (level 2). Neighborhood poverty was strongly associated with higher ESRD incidence for both blacks and whites. Increasing poverty was associated with a greater disparity in ESRD rates between blacks and whites, with the former at greater risk. This raises the possibility that blacks may suffer more from lower socioeconomic conditions than whites. The disparity persisted across all poverty levels. The reasons for increasingly higher ESRD incidence among US blacks as neighborhood poverty increases remain to be explained.

Oxidative stress markers are associated with persistent atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) has been associated with myocardial oxidative stress, and antioxidant agents have demonstrated antiarrhythmic benefit in humans. We compared serum markers of oxidation and associated inflammation in individuals with or without AF.

METHODS

Serum markers of oxidative stress and inflammation were compared in a cross-sectional, case-control design study of 40 male individuals, with or without persistent or permanent AF, who were matched for age, sex, diabetes, and smoking status, known confounding variables for the measurement of oxidative stress. We used derivatives of reactive oxidative metabolites (DROMs) and ratios of oxidized to reduced glutathione (E(h) GSH) and cysteine (E(h) CySH) to quantify oxidative stress. We also measured inflammatory markers, including high-sensitivity C-reactive protein, interleukins 1beta and 6, and tumor necrosis factor alpha.

RESULTS

Univariate, conditional logistical regression analysis showed that oxidative stress but not inflammatory markers were statistically associated with AF (P <0.05). The increase in the odds ratios for AF for E(h) GSH, E(h) CySH, and DROMs were 6.1 (95% CI, 1.3-28.3; P = 0.02), 13.6 (95% CI, 2.5-74.1; P = 0.01), and 15.9 (95% CI, 1.7-153.9; P = 0.02), respectively. There was a stronger correlation between E(h) GSH and E(h) CySH (r = 0.66) than between E(h) GSH and DROMs (r = 0.41). In multivariate analysis corrected for statins and other AF risk factors differing between the groups, the association of AF and oxidative stress remained significant.

CONCLUSIONS

These data suggest that oxidative stress markers may have predictive value in AF management.

Lead exposure and spine bone mineral density

OBJECTIVE

The purpose of this study was to assess changes in spine BMD over time in relation to changes in bone and blood lead levels and baseline risk factors among female former smelter workers in Bunker Hill, Idaho.

METHODS

Spine BMD was measured using Norland XR-26 X-Ray bone densitometer. Cd109 K XRF system was used to estimate tibia bone lead content. Blood lead levels were analyzed using graphite furnace atomic absorption with Zeeman effect background correction. Information about risk factors was obtained through a questionnaire.

RESULTS

In the final backward stepwise multivariate regression model after controlling for baseline BMD, baseline blood lead measured in 1994 and time since menopause; spine bone density in 2000 decreased with increasing blood lead levels in 2000 in all these women, especially if they worked in a technical job (miner) most of the time at the smelter.

CONCLUSIONS

Blood lead may adversely affect bone mineral density.

Evaluation of serum immunoglobulins among individuals living near six Superfund sites

Residents living in communities near Superfund sites have expressed concern that releases from these facilities affect their health, including adverse effects on their immune systems. We used data from six cross-sectional studies to evaluate whether people who live near several Superfund sites are more likely to have individual immunoglobulin test results (IgA, IgG, and IgM) below or above the reference range than those who live in comparison areas with no Superfund site. Study participants consisted of target-area residents who lived close to a Superfund site and comparison-area residents who were not located near any Superfund or hazardous waste sites. A consistent modeling strategy was used across studies to assess the magnitude of the relationship between area of residence and immunoglobulin test results, adjusting for potential confounders and effect modifiers. In all study areas, the results suggest that people who live near a Superfund site may have been more likely to have IgA test results above the reference range than comparison areas residents regardless of modeling strategy employed. The effect measures were larger for residents who lived in communities near military bases with groundwater contamination. For all analyses the wide confidence intervals reflect uncertainty in the magnitude of these effects. To adequately address the question of whether the immune system is affected by low-level exposures to hazardous substances, we recommend that more functional immunotoxicity tests be conducted in human populations where individual exposure information is available or when it can be reasonably estimated from environmental exposure measurements.

The BeLPT: algorithms and implications

BACKGROUND

The beryllium lymphocyte proliferation test (BeLPT) is used to identify persons with beryllium sensitization. The variability of laboratory results and lack of a "gold standard" have led to questions about the test's performance. Fortunately, a recently published study has credibly estimated standard epidemiologic parameters for the BeLPT.

METHODS

Information from this recent study was used to assess the performance of two common algorithms for BeLPT testing. Standard epidemiologic parameters were determined for two common algorithms and then compared.

RESULTS

One of the two algorithms was more sensitive than the other (86% vs. 66%). The specificity of both algorithms (99.8% or greater) was high. At an estimated 2% prevalence, the positive predictive value of both algorithms for beryllium sensitization remained high (90% or higher).

CONCLUSIONS

A priori characterization of the testing algorithm under consideration can enhance public health decision-making.

The value of digital rectal examination as a predictor of prostate cancer diagnosis among United States Veterans referred for prostate biopsy

BACKGROUND

As digital rectal examination (DRE) remains an essential part of a routine physical examination, it is important to understand its diagnostic value in different circumstances.

AIM

To quantify sensitivity, specificity and predictive value of DRE as a predictor of biopsy-confirmed prostate cancer in the US Veteran population.

METHODS

The study group included 628 consecutive patients who underwent transrectal biopsy for suspected prostate cancer due to abnormal digital examination of the prostate, elevated serum prostate specific antigen (PSA) or both. The DRE results reported in this study are documented during physical examinations that were performed after referral for biopsy. The relation between DRE results and positive biopsy was examined while taking into consideration demographic and clinical patient characteristics.

RESULTS

Among men with normal PSA the adjusted odds ratio (OR) reflecting the association between abnormal DRE and positive prostate biopsy was 0.53 with a 95% confidence interval (CI) from 0.27 to 1.06. In the presence of a moderately elevated (4.1-10 ng/mL) PSA, the OR was 1.07 (0.72-1.60). When serum PSA exceeded 10 ng/mL, the OR was 2.15 (1.12-4.43). The positive predictive value of an abnormal DRE varied widely from as high as 81% to as low as 14% depending on the other patient characteristics.

DISCUSSION

These results indicate that DRE results are most informative when evaluated in conjunction with other clinical and demographic information.

A randomised controlled trial of postural interventions for prevention of musculoskeletal symptoms among computer users

AIMS

To examine the effect of two workstation and postural interventions on the incidence of musculoskeletal symptoms among computer users.

METHODS

Randomised controlled trial of two distinct workstation and postural interventions (an alternate intervention and a conventional intervention) among 376 persons using computer keyboards for more than 15 hours per week. The incidence of neck/shoulder symptoms and hand/arm symptoms during six months of follow up among individuals in the intervention groups was compared to the incidence in computer users who did not receive an intervention (comparison group). For individuals in the intervention groups, study staff adjusted workstations, where possible, and trained individuals to assume the intervention postures. Individuals reported musculoskeletal symptoms in a weekly diary. Participants who reported discomfort intensity of 6 or greater on a 0-10 visual analogue scale or who reported musculoskeletal symptoms requiring use of analgesic medication were considered symptomatic.

RESULTS

There were no significant differences in the incidence of musculoskeletal symptoms among the three intervention groups. Twenty two (18.5%) participants in the alternate intervention group, 25 (20.2%) in the conventional intervention group, and 25 (21.7%) in the comparison group developed incident arm or hand symptoms. Thirty eight (33.3%) participants in the alternate intervention group, 36 (31.0%) in the conventional intervention group, and 33 (30.3%) in the comparison group developed incident neck or shoulder symptoms. Compliance with all components of the intervention was attained for only 25-38% of individuals, due mainly to the inflexibility of workstation configurations.

CONCLUSIONS

This study provides evidence that two specific workplace postural interventions are unlikely to reduce the risk of upper extremity musculoskeletal symptoms among computer users.

Effectiveness and cost-effectiveness analysis of neuroreflexotherapy for subacute and chronic low back pain in routine general practice: a cluster randomized, controlled trial

STUDY DESIGN

A cluster randomized, controlled trial was performed.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of adding patients' referral to neuroreflexotherapy intervention to the usual management of subacute and chronic low back pain in routine general practice.

SUMMARY OF BACKGROUND DATA

Neuroreflexotherapy consists of the temporary implantation of epidermal devices in trigger points in the back and referred tender points in the ear. The efficacy of this procedure for treating subacute and chronic low back pain has been demonstrated in previous randomized, double-blind, controlled clinical trials.

METHODS

Twenty-one primary care physicians working in seven primary care centers of the Spanish National Health Service in Palma de Mallorca, Spain, were randomly assigned to the intervention group (n = 11) or the control group (n = 10). The physicians recruited patients who had low back pain that had lasted for 14 or more days despite drug treatment and who did not meet criteria for surgery. The 45 patients recruited by physicians from the control group were treated according to the standard protocol, whereas the 59 patients recruited by physicians from the intervention group were, in addition, referred to neuroreflexotherapy intervention. The analysis of variables was performed taking into account that physicians, not patients, were randomly assigned.

RESULTS

Patients underwent clinical evaluations at baseline and 15, 60, and 365 days later. At baseline, median intensity of pain was higher in patients undergoing neuroreflexotherapy than in control patients (visual analogue scale, 6.07; range, 4.67-8.80 vs. 5.15, range 4.11-8.00) and median duration of pain was also higher (48.1, range 28.4-211.1 vs. 17.5, range 15.0-91.5 days). At the last follow-up visit, patients treated with neuroreflexotherapy showed greater improvement than did control patients in low back pain (visual analogue scale, 5.5; range, 3.7-8.8 vs. 1.9; range, -1.2-3.0; P < 0.001); referred pain (visual analogue scale, 3.6; range, 2.7-7.3 vs. 0.6; range, -1.5-2.0; P = 0.001); and disability (Roland-Morris scale, 8.7; range, 2.0-13.3 vs. 2.0; range, -1.5-6.7; P = 0.007). Moreover, neuroreflexotherapy intervention was associated with a significantly (P < 0.035) lower number of consultations to private or public specialists, fewer indications of radiographs by primary care physicians, lower cost of drug treatment, and less duration of sick leave throughout the follow-up period. There were also differences in favor of neuroreflexotherapy intervention in the cost-effectiveness ratio for pain, disability, and quality of life that persisted in the most optimistic, the most conservative, and the average (break-even case) assumptions.

CONCLUSIONS

Referral to neuroreflexotherapy intervention improves the effectiveness and cost-effectiveness of the management of nonspecific low back pain.

A prospective study of computer users: II. Postural risk factors for musculoskeletal symptoms and disorders

BACKGROUND

Despite widespread recommendations regarding posture during computer use, associations between specific postures and musculoskeletal health are not well characterized.

METHODS

Six hundred and thirty-two newly hired computer users were followed prospectively to evaluate associations between posture and neck or shoulder (N/S) and hand or arm (H/A) musculoskeletal symptoms and musculoskeletal disorders. Participants' postures were measured at entry and they reported symptoms on weekly diaries. Participants reporting symptoms were examined for specific disorders. Multivariate Cox regression models were used to estimate associations between postural variables and risk of symptoms and disorders, controlling for confounding variables.

RESULTS

Keying with an inner elbow angle > 121 degrees, greater downward head tilt, and presence of armrests on the participants chair were associated with lower risk of N/S symptoms or N/S disorders. Keying with elbow height below the height of the "J" key and the presence of a telephone shoulder rest were associated with a greater risk of N/S symptoms or N/S disorders. Horizontal location of the "J" key > 12 cm from the edge of the desk was associated with a lower risk of H/A symptoms and H/A disorders. Use of a keyboard with the "J" key > 3.5 cm above the table surface, key activation force > 48 g, and radial wrist deviation of > 5 degrees while using a mouse was associated with a greater risk of H/A symptoms or H/A disorders. The number of hours keying/week was associated with H/A symptoms and disorders.

CONCLUSIONS

The results suggest that the risk of musculoskeletal symptoms and musculoskeletal disorders may be reduced by encouraging specific seated postures.

A prospective study of computer users: I. Study design and incidence of musculoskeletal symptoms and disorders

BACKGROUND

A prospective study of computer users was performed to determine the occurrence of and evaluate risk factors for neck or shoulder (N/S) and hand or arm (H/A) musculoskeletal symptoms (MSS) and disorders (MSD).

METHODS

Individuals (n = 632) newly hired into jobs requiring > or = 15 hr/week of computer use were followed for up to 3 years. At study entry, workstation dimensions and worker postures were measured and medical and psychosocial risk factors were assessed. Daily diaries were used to document work practices and incident MSS. Those reporting MSS were examined for specific MSD. Incidence rates of MSS and MSD were estimated with survival analysis. Cox regression models were used to evaluate associations between participant characteristics at entry and MSS and MSD.

RESULTS

The annual incidence of N/S MSS was 58 cases/100 person-years and of N/S MSD was 35 cases/100 person-years. The most common N/S MSD was somatic pain syndrome. The annual incidence of H/A MSS was 39 cases/100 person-years and of H/A MSD was 21 cases/100 person-years. The most common H/A disorder was deQuervain's tendonitis. Forty-six percent of N/S and 32% of H/A MSS occurred during the first month of follow-up. Gender, age, ethnicity, and prior history of N/S pain were associated with N/S MSS and MSD. Gender, prior history of H/A pain, prior computer use, and children at home were associated with either H/A MSS or MSD.

CONCLUSIONS

H/A and N/S MSS and MSD were common among computer users. More than 50% of computer users reported MSS during the first year after starting a new job.

Predictors of Chlamydia trachomatis infection among female adolescents: a longitudinal analysis

Screening guidelines recommend testing all sexually active female adolescents for Chlamydia trachomatis during a pelvic examination at each clinic visit. Such criteria have been based on cross-sectional studies; new evaluations should take into account multiple clinic visits and assess whether criteria are appropriate when a prior test is negative and risk factors are absent. Because repeated observations on an individual may be correlated, the authors used the generalized estimating equation method. Little information exists on subsequent risk of infection; as control programs develop, approaches targeting high-risk populations for recurrent infections are needed. Using data on females aged 15-19 years who visited family planning clinics more than once from 1988 to 1992 (n = 26,921) in Region X (Alaska, Idaho, Oregon, and Washington), the authors constructed a retrospective cohort. Teens with chlamydia at their first visit were at high risk for subsequent infection (odds ratio = 1.6, 95% confidence interval 1.4-1.7). Among teens uninfected at the first visit and without risk factors at the second, prevalence at the second visit was 6%. When intervisit correlations using the generalized estimating equation method were taken into account, predictors of chlamydial infection were consistent with those in previous cross sectional studies cervicitis, friable cervix, and multiple, new, or symptomatic sex partner(s). These findings support screening sexually active female adolescents at each visit, even if prior tests results are available.

Relation of lead and social factors to IQ of low-SES children: a partial replication

An independent replication of a previous study (Schroeder et al., 1985) of the effects of interactive social environmental factors on the relationship of lead and Stanford-Binet IQ was performed on 75 of 80 low-SES black children screened by county health departments in North Carolina. Children's mean blood lead (PbB) level was 20.8 micrograms/dl (range, 6.3 to 47.4). Multivariate regression analyses showed no significant interactions between PbB and age, sex, maternal IQ, Caldwell home environment score, or SES (Hollingshead Two-Factor Index). There was a highly significant negative relationship between both mean and maximum PbB levels with IQ, p less than .002; that is, IQ decreased linearly as PbB increased. The most accurate and precise regression model included lead, maternal IQ, home environment, and gender.

Alcohol consumption as a risk factor for high blood pressure. Munich Blood Pressure Study

The Munich Blood Pressure Study (MBS), a 1980-81 cross-sectional study (with follow-up) of a random sample of 3198 Munich citizens aged 30-69 years (response rate 69%), revealed hypertensive blood pressure (BP) values in 17.7% of men and 10.7% of women (WHO criteria). One of the main goals of the MBS was to search for social, behavioral, and environmental risk factors for hypertension. The relationship between BP and five possible risk factors--alcohol consumption (g/day), cigarette smoking, oral contraceptive use, years of education, obesity (BMI)--has been examined. The major emphasis of this report is the relationship of alcohol consumption to BP. Multiple linear and logistic regression analyses were run controlling for both age and sex. All second- and third-order interactions between the independent variables were tested during a backward-stepping procedure. Alcohol consumption appeared as a significant main effect in many of the analyses. The coefficient of the alcohol variable ranged from 0.02 to 0.06 for men and women in the separate linear regression analyses for systolic and diastolic BP. Thus, for example, according to the model, the daily consumption of 1 liter of beer (40 g alcohol) may cause an increase in diastolic BP in women of 2.4 mm Hg.

A method for selecting criteria to evaluate medical care

This study tests a questionnaire method for eliciting process criteria for medical care appraisal. The questionnaire was sent to national samples of family physicians, pediatricians, and pediatricians specializing in infectious diseases asking their opinions about various clinical actions in 125 clinical situations concerning respiratory infection in infants. Five hundred twenty-four (54%) physicians returned completed questionnaires. Questionnaire responses favored the performance of a majority of actions and opposed very few. Opinions concerning individual actions, particularly diagnostic tests and treatments, varied widely depending upon the clinical situation presented. A second questionnaire sent one year later indicated that the opinions expressed in the first questionnaire remained stable over time, especially if the initial opinion favored performance of the action. Comparison of the questionnaire responses and medical records of a group of practitioners demonstrated that only 55% of actions favored in a practitioner's questionnaire appeared in his records. Although the questionnaire method appears to be a feasible, specific, and reliable means of identifying clinical opinion, there remains considerable discordance between opinion as expressed in the questionnaire and recorded clinical practice.