OBJECTIVE

Among persons with lower extremity peripheral artery disease (PAD), we determined whether objective measures of walking performance predict mortality independently of the ankle brachial index (ABI).

BACKGROUND

The ability of office-based functional performance measures to predict mortality in patients with PAD is unknown.

METHODS

Participants were 444 persons with PAD followed prospectively for 4.8 years. The 6-min walk and 4-m walks at usual and fastest pace were measured at baseline. Cox proportional hazard models were used to assess relations between baseline measures of lower extremity performance with mortality, adjusting for confounders.

RESULTS

One hundred twenty-seven patients (28.6%) died during follow-up. Adjusting for age, gender, race, comorbidities, ABI, and other confounders, participants in the poorest baseline quartile of 6-min walk performance had significantly increased total mortality (hazard ratio [HR] 2.36 [95% confidence interval (CI) 1.33 to 4.18]) and cardiovascular mortality (HR 5.59 [95% CI 1.97 to 15.9]) compared with the best quartile of baseline performance. Participants in the poorest baseline quartile of normal-paced 4-m walking speed had significantly increased total mortality (HR 1.86 [95% CI 1.06 to 3.29]) and cardiovascular mortality (HR 2.55 [95% CI 1.01 to 6.46]) compared with the best quartile of baseline performance.

CONCLUSIONS

This study demonstrates for the first time that performance-based measures, which can be administered in an office setting, provide prognostic information regarding mortality in persons with PAD beyond that provided by the ABI.

Increased expression of interferon (IFN)-inducible genes is implicated in the pathogenesis of systemic lupus erythematosus (SLE). One transcription factor responsible for regulating IFN, interferon regulatory factor-5 (IRF5), has been associated with SLE in genetic studies of Asian, Caucasian and Hispanic populations. We genotyped up to seven polymorphic loci in or near IRF5 in a total of 4870 African-American and Caucasian subjects (1829 SLE sporadic cases and 3041 controls) from two independent studies. Population-based case-control comparisons were performed using the Pearson's chi(2)-test statistics and haplotypes were inferred using HaploView. We observed significant novel associations with the IRF5 variants rs2004640 and rs3807306 in African Americans and replicated previously reported associations in Caucasians. While we identified risk haplotypes, the majority of haplotypic effects were accounted for by one SNP (rs3807306) in conditional analyses. We conclude that genetic variants of IRF5 associate with SLE in multiple populations, providing evidence that IRF5 is likely to be a crucial component in SLE pathogenesis among multiple ethnic groups.

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that is believed to have a genetic basis. However, no specific susceptibility gene or region has been conclusively identified.

OBJECTIVE

The objective of this study was to duplicate a previous study that localized a PCOS susceptibility region to chromosome 19p13.2 and to narrow the susceptibility region.

METHODS

This study was designed to test for genetic linkage and association between PCOS and short tandem repeat polymorphisms in 367 families, by analysis of linkage and family-based association.

METHODS

The study was conducted at academic medical centers.

METHODS

We studied 367 families of predominantly European origin with at least one PCOS patient. Families included 107 affected sibling (sister) pairs (ASPs) in 83 families, and 390 trios with both parents and an affected daughter. The data set comprises two independent groups. Set 1 consists of 44 ASPs and 163 trios. Set 2 consists of 63 ASPs and 227 trios.

METHODS

The intervention was the drawing of blood for DNA extraction.

METHODS

We employed measures of evidence for linkage and association between PCOS and 19 STRs.

RESULTS

Linkage with PCOS was observed over a broad region of chromosome 19p13.2. The strongest evidence for association was observed with D19S884 (chi2 = 11.85; nominal P < 0.0006; permutation P = 0.034) and duplicated our earlier findings.

CONCLUSIONS

The present analysis suggests that a PCOS susceptibility locus maps very close to D19S884. Additional studies that systematically characterize DNA sequence variation in the immediate area of D19S884 are required to identify the PCOS susceptibility variant.

OBJECTIVE

To assess associations between abacavir (ABC) use and systemic inflammation.

METHODS

Nested case-control study.

METHODS

The Multicenter AIDS Cohort Study (MACS) and Women's Interagency HIV Study (WIHS) cohort participants who initiated ABC were matched, using propensity score methods, to ABC-unexposed persons. Levels of high-sensitivity C-reactive protein (hsCRP) (microg/ml), interleukin-6 (IL-6) (pg/ml), and D-dimer (microg/ml) were measured from pre-HAART and on-HAART plasma. Random-effects models compared markers by ABC exposure and by changes from pre-HAART levels.

RESULTS

Biomarkers were measured in N = 508 matched pairs (328 women; 180 men). Pre-HAART levels did not differ by exposure group except that hsCRP levels were higher among WIHS women who subsequently used ABC (P = 0.04). Regardless of ABC use, mean hsCRP increases and D-dimer reductions were seen when comparing pre-HAART to on-HAART levels, in the overall group (28 and -27%), for MACS men (28 and -31%) and for WIHS women [29 and -24%, P < 0.01 for all]; IL-6 levels declined in MACS men (P = 0.02). No adjusted biomarker level differences existed by ABC exposure at the on-HAART visit. HIV RNA reductions correlated with D-dimer (r = 0.14, P < 0.01) and IL-6 (r = 0.12, P < 0.01) reductions. Associations between ABC use and mean biomarker levels were modified by pre-HAART antiretroviral therapy experience. Renal dysfunction was equally likely among non-ABC and ABC recipients.

CONCLUSIONS

ABC use was not associated with plasma elevations in hsCRP, IL-6, and D-dimer. Mechanisms other than increased systemic inflammation may account for ABC's reported association with increased cardiovascular disease. HAART-associated reductions in D-dimer and IL-6 were apparent regardless of ABC use and were correlated with HIV RNA reductions.

OBJECTIVE

To describe vascular events during an 8-year followup in a multicenter systemic lupus erythematosus (SLE) inception cohort and their attribution to atherosclerosis.

METHODS

Clinical data, including comorbidities, were recorded yearly. Vascular events were recorded and attributed to atherosclerosis or not. All of the events met standard clinical criteria. Factors associated with atherosclerotic vascular events were analyzed using descriptive statistics, t-tests, and chi-square tests. Stepwise multivariate logistic regression was used to assess the association of factors with vascular events attributed to atherosclerosis.

RESULTS

Since 2000, 1,249 patients have been entered into the cohort. There have been 97 vascular events in 72 patients, including: myocardial infarction (n = 13), angina (n = 15), congestive heart failure (n = 24), peripheral vascular disease (n = 8), transient ischemic attack (n = 13), stroke (n = 23), and pacemaker insertion (n = 1). Fifty of the events were attributed to active lupus, 31 events in 22 patients were attributed to atherosclerosis, and 16 events were attributed to other causes. The mean +/- SD time from diagnosis to the first atherosclerotic event was 2.0 +/- 1.5 years. Compared with patients followed for 2 years without atherosclerotic events (n = 615), at enrollment, patients with atherosclerotic vascular events were more frequently white, men, older at diagnosis of SLE, obese, smokers, hypertensive, and had a family history of coronary artery disease. On multivariate analysis, only male sex and older age at diagnosis were associated factors.

CONCLUSIONS

In an inception cohort with SLE followed for up to 8 years, there were 97 vascular events, but only 31 were attributable to atherosclerosis. Patients with atherosclerotic events were more likely to be men and to be older at diagnosis of SLE.

Interferon regulatory factor 5 (IRF5) belongs to a family of transcription factors that control the transactivation of type I interferon system-related genes, as well as the expression of several other genes involved in immune response, cell signalling, cell cycle control and apoptosis. Two recent studies reported a significant association between the IRF5/rs2004640 T allele and systemic lupus erythematosus (SLE). The purpose of this study was to determine whether the reported rs2004640 T allele association could be replicated in our independent SLE case-control sample. We genotyped DNA samples from 370 white SLE-affected female subjects and 462 white healthy female controls using the TaqMan Assay-on-Demand for rs2004640, and performed a case-control genetic association analysis. Frequency of the rs2004640 T allele was significantly higher in cases than in controls (56.5% vs. 50%; P= 0.008). The odds ratio for T allele carriers was 1.68 (95% CI: 1.20 - 2.34; P= 0.003). Our results in an independent case-control sample confirm the robust association of the IRF5/rs2004640 T allele with SLE risk, and further support the relevance of the type I interferon system in the pathogenesis of SLE and autoimmunity.

OBJECTIVE

Toll-like receptors (TLR) play an important role in both adaptive and innate immunity. Variations in TLR genes have been shown to be associated with various infectious and inflammatory diseases. We investigated the association of TLR5 (Arg392Stop, rs5744168) and TLR9 (-1237T->>C, rs5743836) single nucleotide polymorphisms (SNP) with systemic lupus erythematosus (SLE) in Caucasian American subjects.

METHODS

We performed a case-control association study and genotyped 409 Caucasian women with SLE and 509 Caucasian healthy female controls using TaqMan allelic discrimination (rs5744168) or polymerase chain reaction-restriction fragment length polymorphism analysis (rs5743836).

RESULTS

None of the 2 TLR SNP showed a statistically significant association with SLE risk in our cohort.

CONCLUSIONS

Our results do not indicate a major influence of these putative functional TLR SNP on the susceptibility to (or protection from) SLE.

BACKGROUND

Exercise improves sleep quality, mood, and quality of life among older adults with insomnia. The purpose of the study was to evaluate the daily bidirectional relationships between exercise and sleep in a sample of women with insomnia.

METHODS

Participants included 11 women (age M = 61.27, SD 4.15) with insomnia who engaged in 30 min of aerobic exercise 3 times per week. Self-reported sleep quality was assessed at baseline and at 16 weeks. Sleep and exercise logs and wrist activity were collected continuously. Sleep variables included subjective sleep quality and objective measures recorded via wrist actigraphy (sleep onset latency [SOL], total sleep time [TST], sleep efficiency [SE], wake after sleep onset [WASO], and fragmentation index [FI]). Age, subjective sleep quality, TST, SOL, and physical fitness at baseline were tested as moderators of the daily effects.

RESULTS

TST, SE, and self-reported global sleep quality improved from baseline to 16 weeks (p values < 0.05). Baseline ratings of sleepiness were negatively correlated with exercise session duration (p < 0.05). Daily exercise was not associated with subjective or objective sleep variables during the corresponding night. However, participants had shorter exercise duration following nights with longer SOL (p < 0.05). TST at baseline moderated the daily relationship between TST and next day exercise duration (p < 0.05). The relationship between shorter TST and shorter next day exercise was stronger in participants who had shorter TST at baseline.

CONCLUSIONS

Results suggest that sleep influences next day exercise rather than exercise influencing sleep. The relationship between TST and next day exercise was stronger for those with shorter TST at baseline. These results suggest that improving sleep may encourage exercise participation.

BACKGROUND

Our objectives were to determine whether obesity is associated with a greater functional decline compared with the ideal body mass index (BMI) among persons with peripheral arterial disease (PAD) and to determine the associations between weight gain and loss and functional declines in PAD. We hypothesized that baseline obesity and weight gain during follow-up would each be associated with functional declines in persons with PAD.

METHODS

The design was a prospective cohort study. The subjects were 389 men and women with PAD (mean ankle-brachial index, 0.65 +/- 0.14) who were followed up prospectively for a median of 48 months. The main outcome measures were functional assessments (6-minute walk, usual- and rapid-paced 4-m walking speed, and summary performance score). Weight and height were measured at baseline and annually. Results were adjusted for age, sex, race, comorbidities, ankle-brachial index, education, leg symptoms, exercise status, depressive symptoms, pack-years of cigarette smoking, prior-year functioning, and patterns of missing data.

RESULTS

Compared with those with a baseline BMI between 20 and 25 kg/m2, PAD participants with baseline BMI greater than 30 kg/m2 had a significantly greater average annual decline in 6-minute walk performance (-13.1 vs -26.5 m/y; P = .004), usual-paced 4-m walking velocity (-0.028 vs -0.055 m/s per year; P = .024), and fast-paced 4-m walking velocity (-0.053 vs -0.086 m/s per year; P = .012). Persons with weight gain between 5 and 10 pounds after baseline who walked for exercise regularly had significantly less decline in the 6-minute walk than persons without significant weight change who did not walk for exercise (P = .04).

CONCLUSIONS

Obesity is associated with functional decline in persons with PAD. Walking exercise may protect against functional decline in PAD persons with modest weight gain.

BACKGROUND

Inactivating mutations of the FSH receptor (FSHR) are a rare cause of hypergonadotrophic hypogonadism in women. Only one patient with primary amenorrhoea due to an FSHR gene mutation has been reported outside of Finland, where the prevalence of Ala189Val mutations is particularly high.

RESULTS

Here, we describe the clinical, molecular genetic and functional characteristics associated with a novel inactivating mutation in exon 10 of the FSHR gene identified in a patient who presented with primary amenorrhoea at 17 years of age. The C to G transversion found at nucleotide 1043 causes a Pro348Arg substitution in the extracellular region of the FSHR and results in a mutant FSHR that is completely inactive in functional studies and that does not bind FSH. The proband exhibits apparent homozygosity for this recessive mutation. Her father is heterozygous for the mutation while analysis of exon 10 of the FSHR gene from her mother revealed only wild-type sequence. Chromosome painting was used to exclude deletions or rearrangements of 2p, and microsatellite markers did not show paternal uniparental isodisomy for this region. These findings suggest that the proband is hemizygous, with an inherited or de-novo microdeletion, or alternatively a de-novo gene conversion, of the accompanying FSHR allele.

CONCLUSIONS

This case confirms the importance of the FSHR in female pubertal development and reproduction, and supports a relationship between phenotype and function for FSHR mutations.

Although frequency-domain analysis of heart rate variability (HRV) has been performed in the setting of exercise and recovery from exercise, the relationship of specific frequency components to sympathetic and parasympathetic inputs has not been validated in this setting. The aim of this study is to evaluate the relationship of frequency components of HRV to sympathetic and parasympathetic modulation in the setting of recovery after exercise using selective autonomic blockade. Normal subjects (n = 27, 17 men, 53 +/- 7 yr old) underwent bicycle stress testing on four separate days. On day 1, a baseline study without autonomic blockade was performed. On days 2 through 4, either beta-adrenergic, parasympathetic, or double blockade was administered during exercise and completed 3 min before recovery. Continuous ECG was recorded for 5 min starting from the end of exercise. Time- and frequency-domain measures of HRV were computed for each of the five 1-min segments of RR intervals. Parasympathetic blockade significantly decreased all the HRV measures compared with baseline (P < 0.02 for all). Root mean square of successive differences of RR intervals (rMSSD) was increased by beta-adrenergic blockade (P < 0.0002). All the HRV measures except rMSSD showed increases with time after the first minute of recovery. The low frequency-to-high frequency ratio did not respond to autonomic blockade or to recovery time, consistent with the expected changes in sympathovagal influence. Root mean square (detrended SD) and rMSSD were highly correlated with the square root of the total power (r = 0.96) and high-frequency power (r = 0.95), respectively. Although there are marked reductions in the frequency-domain measures in recovery versus rest, the fluctuations in the low- and high-frequency bands respond to autonomic blockade in the expected fashion. Time-domain measures of HRV were highly correlated with frequency-domain measures and therefore provide a computationally more efficient assessment of autonomic influences during recovery from exercise that is less susceptible to anomalies of frequency-domain analysis.

Patients with systemic lupus erythematosus (SLE) are at increased risk for cardiovascular (CV) disease. The aim of this study was to investigate the association between subclinical CV disease as measured by carotid intima-media thickness (IMT) and plaque using B-mode carotid ultrasound and incident CV events in a combined cohort of female patients with SLE. This was a prospective, 2-center observational study of 392 adult women with SLE and no previous CV events with a mean 8 years of follow-up. Incident CV events confirmed by clinicians were defined as angina, myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass graft, fatal cardiac arrest, transient ischemic attack, and cerebrovascular accident. Incident hard CV events excluded angina and transient ischemic attack. The mean age was 43.5 years, and most patients were Caucasian (77.3%). During follow-up, 38 patients had incident CV events, and 17 had incident hard CV events. Patients with incident hard CV events had higher mean carotid IMT (0.80 vs 0.64 mm, p <0.01) and presence of carotid plaque (76.5% vs 30.4%, p <0.01) compared with those without incident hard CV events. Baseline carotid IMT and presence of plaque were predictive of any incident hard CV event (hazard ratio 1.35, 95% confidence interval 1.12 to 1.64, and hazard ratio 4.26, 95% confidence interval 1.23 to 14.83, respectively), independent of traditional CV risk factors and medication use. In conclusion, in women with SLE without previous CV events, carotid IMT and plaque are predictive of future CV events. This suggests that carotid ultrasound may provide an additional tool for CV risk stratification in patients with SLE.

OBJECTIVE

Hyperandrogenemia, insulin resistance, and dyslipidemia demonstrate familial aggregation in the female first-degree relatives of women with polycystic ovary syndrome (PCOS), suggesting that these defects are heritable. Hyperandrogenemia also appears to be the male reproductive phenotype. We performed this study to test the hypothesis that brothers of women with PCOS have metabolic defects similar to those of their proband sisters.

METHODS

This was a prospective case-control study performed at four academic medical centers in the U.S. Fasting blood was obtained from 196 non-Hispanic white brothers of women with PCOS and 169 control men of age, BMI, and ethnicity comparable to those of brothers. A separate analysis was performed by study site to assess potential regional variations in metabolic parameters.

RESULTS

Overall, brothers of women with PCOS had significantly higher total (P = 0.001) and LDL cholesterol (P = 0.01) as well as triglyceride levels (P = 0.01) compared with control men, although there were regional variations in these differences. There were significant positive correlations between brothers and their sisters with PCOS for total (rho = 0.2, P = 0.009) and LDL cholesterol (rho = 0.3, P = 0.001) and triglyceride (rho = 0.2, P = 0.05) levels. Brothers also had significantly higher fasting insulin levels and homeostatic index of insulin resistance (P = 0.02 for both comparisons) compared with control men.

CONCLUSIONS

Brothers of women with PCOS have dyslipidemia as well as evidence for insulin resistance similar to that of their proband sisters with PCOS. These findings are consistent with the hypothesis that some metabolic abnormalities in PCOS are heritable and are not sex specific.

Racial differences exist in disease rates and mortality in both cardiovascular disease (CVD) and systemic lupus erythematosus (SLE). The objective of this cross-sectional study was to compare the frequency and risk factors for subclinical CVD in African American (AA) and Caucasian women with SLE and no prior CVD events. Traditional CVD risk factors and SLE-related factors were assessed in 309 SLE women. Subclinical CVD was assessed by carotid ultrasound to measure intimamedial thickness (IMT) and plaque, and electron beam computed tomography (EBCT) was used to measure coronary artery calcium (CAC). AA women had less education and higher levels of body mass index, blood pressure, lipoprotein(a), C-reactive protein (CRP), fibrinogen, and erythrocyte sedimentation rate (ESR). However, AA women had lower albumin, more and longer duration of corticosteroid use, higher SLE disease activity and damage, and more dsDNA antibodies compared with Caucasian women after adjustment for age and study site. More AA women had carotid plaque (adjusted odds ratio [OR], 1.94; 95% confidence interval [CI], 1.03-3.65) and higher carotid IMT (0.620 vs 0.605 mm, P = 0.07) but similar CAC compared with Caucasians. A multivariate analysis revealed that the following risk factor variables were significantly different between the racial groups and associated with plaque: blood pressure, current corticosteroid use, SLE disease activity, and SLE damage. All factors contributed to the result, but no individual risk factor fully accounted for the association between race and plaque. In conclusion, the presence of carotid plaque was higher in AA compared with Caucasian women with SLE, in contrast to studies of non-SLE subjects, in which AA have similar or less plaque than Caucasians. A combination of SLE-related and traditional CVD risk factors explained the racial difference in plaque burden.

The purpose of the study was to measure the concentrations of estradiol, its primary precursors, and factors with which it interacts in the breast, and determine their sources of variation. Nipple aspirate fluid (NAF) was collected from premenopausal women during the mid-luteal phase of the menstrual cycle. The fluid was diluted and unconjugated steroids were extracted. Estradiol was further purified by a solvent partition into aqueous NaOH. Androgens were measured in the non-phenolic fraction. Water-soluble, conjugated steroids and proteins were measured in the aqueous residue. All analytes were measured by immunoassays. Permutation methods were used to determine the correlations over multiple periods of time. The average concentration of estradiol in NAF was 435 pmol/L after purification but was many times higher when assayed without purification. Estrone and dehydroepiandrosterone (DHEA) sulfates were present in 3.7 and 75 micromol/L concentrations, respectively, while unconjugated androstenedione and DHEA were present in nanomole per liter concentrations. Lack of the steroid sulfates in NAF in 19% of subjects had no effect on NAF estradiol levels but was associated with a 77% lower concentration of unconjugated DHEA. Progesterone was present in concentrations that were 3- to 4-fold higher than normal serum concentrations (mean: 291 nmol/L). Cathepsin D, epidermal growth factor, and interleukin 6 had average values of 3.4 microg/mL, 424 ng/mL, and 1.7 ng/mL, respectively. Correlations between breasts were between 0.57 and 0.84 for the several analytes; correlations over time ranged from 0.64 and 0.93 with estrone sulfate highest in both categories. The lower correlation between breasts than within breasts indicates that local factors play an important role in determining the levels of many of these analytes in the breast. The high stability of the concentrations of several analytes over time indicates that fluctuations in environmental factors have little immediate effect on levels in the breast, and portends their utility as surrogate breast cancer risk markers.

BACKGROUND

The prevalence of allergic diseases is increasing worldwide, but the reasons are not well understood. Previous studies suggest that this trend might be associated with lifestyle and urbanization.

OBJECTIVE

We sought to describe patterns of sensitization and allergic disease in an unselected agricultural Chinese population.

METHODS

The data were derived from a community-based twin study in Anqing, China. Skin prick tests were performed to foods and aeroallergens. Atopy was defined as sensitization to 1 or more allergens. Allergic disease was ascertained by means of self-report. The analysis was stratified by sex and age (children [11-17 years] and adults >>or=18 years]) and included 1059 same-sex twin pairs.

RESULTS

Of 2118 subjects, 57.6% were male (n = 1220). Ages ranged from 11 to 71 years, and 43.3% were children (n = 918). Atopy was observed in 47.2% (n = 999) of participants. The most common sensitizing foods were shellfish (16.7%) and peanut (12.3%). The most common sensitizing aeroallergens were dust mite (30.6%) and cockroach (25.2%). Birth order and zygosity had no effect on sensitization rates. Multivariate logistic regression models revealed that risk factors for sensitization include age for foods and sex for aeroallergens. The rates of food allergy and asthma were estimated to be less than 1%.

CONCLUSIONS

Atopic sensitization was common in this rural farming Chinese population, particularly to shellfish, peanut, dust mite, and cockroach. The prevalence of allergic disease, in contrast, was quite low.

Our goal was to compare direct and indirect medical costs and quality of life associated with inpatient vs outpatient autologous hematopoietic stem cell transplantation (AuHSCT). Twenty-one sequential outpatients and 26 inpatients were enrolled on this prospective trial. All candidates for AuHSCT were screened for eligibility for outpatient transplantation. Patients with either breast cancer or hematologic malignancy, insurance coverage for the outpatient procedure, one to three caregivers available to provide 24 h coverage, and no significant comorbidities were eligible to participate. Patients without caregivers or insurance coverage for outpatient transplant were accrued to the study in a consecutive manner as inpatient controls, based on willingness to participate in the quality of life portion of the study and to permit review of their hospital and billing records. Approximately half of all 139 prospective outpatient candidates were ineligible because they lacked a caregiver. Most commonly, the patient without a caregiver was single or widowed or their family and friends were needed to provide childcare. Most caregivers were college educated from families with incomes greater than US dollars 80000. Indirect costs to the caregivers totaled a median of US dollars 2520 (range US dollars 684-US dollars 4508), with the majority attributed to lost 'opportunity costs'. Overall, there were significant differences in the total costs of treatment for inpatient vs outpatient AuHSCT (US dollars 40985 vs US dollars 29210, P < 0.01)). In general, no significant differences were detected between inpatient and outpatient scores on quality of life measures. Although significant cost savings were associated with outpatient transplantation, this approach was applicable to only half of our otherwise eligible candidates because of a lack of caregivers. The financial burden associated with the caretaking role may underlie this finding.

OBJECTIVE

To determine whether asymptomatic lower extremity peripheral arterial disease (PAD) and leg symptoms other than intermittent claudication (IC) in PAD are associated with faster functional decline than in people with both PAD and IC.

METHODS

Prospective, observational study.

METHODS

Chicago-area medical center.

METHODS

Four hundred fifteen people with PAD followed annually for up to 7 years.

METHODS

At baseline, patients with PAD were categorized into symptom categories, including IC; leg pain on exertion and rest; participants who could walk through exertional leg pain (pain/carry on); and participants who never experienced exertional leg pain, even during the 6-minute walk (always asymptomatic). Outcomes included mobility loss (becoming unable to walk one-quarter of a mile or walk up and down one flight of stairs without assistance) and becoming unable to complete the 6-minute walk without stopping. Analyses adjusted for age, sex, comorbidities, ankle brachial index, and other confounders.

RESULTS

Always-asymptomatic participants (hazard ratio (HR)=2.94, 95% confidence interval (CI)=1.39-6.19, P=.005) and those with leg pain on exertion and rest (HR=2.89, 95% CI=1.47-5.68, P=.002) had greater mobility loss than participants with IC. Participants with PAD with leg pain/carry on were less likely (P=.047) to become unable to walk for 6 minutes continuously without stopping than participants with IC.

CONCLUSIONS

The ABI identifies patients with asymptomatic PAD and those with atypical leg symptoms who are at risk for greater mobility decline than participants without PAD and participants with PAD with IC.

BACKGROUND

This study analyzes Chicago-area weather effects on objectively measured physical activity over a 3-year period among a cohort of 241 participants in an on-going arthritis physical activity trial.

METHODS

Uniaxial accelerometer counts and interview data were analyzed for up to 6 weekly study waves involving 4823 days of wear. The effects of temperature, rainfall, snowfall and daylight hours were analyzed after controlling for participant characteristics, day of the week, and daily accelerometer wear hours in a mixed effects linear regression model.

RESULTS

Daylight hours, mean daily temperature < 20 or ≥ 75 degrees, and light or heavy rainfall (but not snowfall) were all significantly associated with lower physical activity after controlling for the significant effects of weekends, accelerometer wear hours, age, sex, type of arthritis, employment, Hispanic ethnicity, obesity, and SF36 physical and mental health scores.

CONCLUSIONS

The cumulative effects of weather are reflected in a 38.3% mean monthly difference in daily counts between November and June, reflecting over 3 additional hours of sedentary time. Physical activity promotion programs for older persons with chronic conditions need lifestyle physical activity plans adapted to weather extremes.

OBJECTIVE

Chronic abdominal pain (AP) is common in children. Recall of symptoms is used clinically to determine management, to assess treatment progress, and in drug studies to assess outcomes. Limited data exist on accuracy of AP recall in children. The aim of the present study was to assess ability to accurately recall AP in children.

METHODS

The study was a secondary analysis of data obtained from a double-blind, randomized, placebo-controlled trial, evaluating amitriptyline in children with functional gastrointestinal disorders. Children ages 8 to 17 years with AP predominant functional gastrointestinal disorders based on Rome II criteria were recruited from 6 centers. Those with evidence of organic disease were excluded. Patients maintained AP diary daily for 1 month (presence, frequency, and intensity). At the end of the study, patients reported the number of days of AP during previous month. Agreement between daily pain reports and recalled pain was assessed. Univariate analysis was conducted with Spearman rank correlations.

RESULTS

We recruited 63 children (45 girls, mean age 12.8 years). Sixteen percent children had perfect agreement on number of days of AP. Fifty-four percent of children recalled fewer episodes of pain. The average number of days with AP by recall was 17.7/month, whereas by diary it was 23.5/month (P = 0.001). Correlation between patient recall of the last week of symptoms (r = 0.47) was no better than correlation between recall of the last 30 days of symptoms (r = 0.48). On comparing AP recall versus various pain intensities, reported AP did not reflect only AP of greater severity. Higher correlation of recall of symptoms was seen in children 11 years or younger (r = 0.59) as compared with children older than 11 years (r = 0.26).

CONCLUSIONS

Few children can accurately recall the episodes of AP. Children commonly recall a lower frequency of AP than that assessed by prospective diary reports. Reported recall does not reflect a shorter recollection period. Recall is not related to intensity of pain. Adolescents have worse recall of symptoms.

Confirmation of gene expression by a second methodology is critical in order to detect false-positive findings associated with microarrays. However, the impact of methodology upon the measurement of gene expression has not been rigorously evaluated. In the current study, we compared differential gene expression between PC3 and PC3-M human prostate cancer cell lines using three separate methods: microarray, quantitative RT/PCR (qRT/PCR), and Northern blotting. The PC3 to PC3-M ratio of gene expression was determined for each of 24 different genes evaluated, by each of the three methods. Comparison of gene expression ratios between Northern and microarray, Northern and qRT/PCR, and microarray and qRT/PCR, gave correlation coefficients (r) of 0.72, 0.39, and 0.63, respectively. In each instance, one to two outlier genes were apparent. Their exclusion from analysis gave r values of 0.79, 0.72, and 0.83, respectively. These findings demonstrate that the assessment of differential gene expression is dependent upon the methodology used in each situation where outcome between different methodologies was compared, the presence of a relatively limited number of outlier genes precludes high overall correlation between the methods. Validation of gene expression by different methods should be performed whenever possible.

OBJECTIVE

To determine whether poor lower extremity nerve function is associated with less-favorable calf muscle characteristics and greater functional impairment in people with and without peripheral arterial disease (PAD).

METHODS

Cross-sectional.

METHODS

Three Chicago-area medical centers.

METHODS

Four hundred thirteen participants with PAD (ankle-brachial index (ABI) < 0.90) and 255 without.

METHODS

Electrodiagnostic testing of the peroneal nerve was performed. Calf muscle cross-sectional area and percentage fat were measured using computed tomography at 66.7% of the distance between the distal and proximal tibia. Six-minute walk performance was measured.

RESULTS

Adjusting for age, sex, race, ABI, leg symptoms, smoking, physical activity, comorbidities, and other covariates, lower peroneal nerve conduction velocity (NCV) was associated with lower calf muscle area (first quartile 4,770.3 mm(2) , fourth quartile 5,571 mm(2) , P < .001) and poorer 6-minute walk distance (first quartile 989.2 feet, fourth quartile 1,210.8 feet, P < .001) in participants without diabetes mellitus with PAD. Lower peroneal NCV was associated with lower calf muscle area (first quartile 5,166.0 mm(2) , fourth quartile 6,003.8 mm(2) , P = .01) and poorer 6-minute walk distance (first quartile 866.4 feet, fourth quartile 1,082.5 feet, P = .01) in participants with diabetes mellitus and PAD as well. In participants without PAD, lower peroneal NCV was not associated with lower calf muscle area but was associated with poorer 6-minute walk distance only in participants without diabetes mellitus (first quartile 1,317.0 feet, fourth quartile 1,570.4 feet, P-trend < .001).

CONCLUSIONS

Lower peroneal nerve function is associated with smaller calf muscle area and greater functional impairment in individuals with PAD. Future study is needed to determine whether improving peroneal NCV prevents loss of calf muscle and functional decline in people with PAD.

OBJECTIVE

To test further the hypothesis that autosomal dominant neurohypophyseal diabetes insipidus (adFNDI) is caused by heterozygous mutations in the vasopressin-neurophysin II (AVP-NPII) gene that exert a dominant negative effect by producing a precursor that misfolds, accumulates and eventually destroys the neurosecretory neurons.

METHODS

Antidiuretic function, magnetic resonance imaging (MRI) of the posterior pituitary and AVP-NPII gene analysis were performed in 10 affected members of three unreported families with adFNDI.

RESULTS

As in previously studied patients, adFNDI apparently manifested after birth, was due to a partial or severe deficiency of AVP, and was associated with absence or diminution of the hyperintense MRI signal normally emitted by the posterior pituitary, and with a heterozygous mutation in the AVP-NPII gene. In family A, a transition 275G->>A, which predicts replacement of cysteine 92 by tyrosine (C92Y), was found in the index patient, but not in either parent, indicating that it arose de novo. The six affected members of family B had a transversion 160G->>C, which predicts replacement of glycine 54 by arginine (G54R). It appeared de novo in the oldest affected member, and was transmitted in a dominant manner. In family C, six of 15 living affected members were tested and all had a novel transition, 313T->>C, which predicts replacement of cysteine 105 by arginine (C105R). It, too, was transmitted in a dominant manner. As in other patients with adFNDI, the amino acids replaced by the mutations in these three families are known to be particularly important for correct and efficient folding of the precursor.

CONCLUSIONS

These findings are consistent with the malfolding/toxicity hypothesis underlying the pathogenesis of adFNDI. Moreover, they illustrate the value of genetic analysis in all patients who develop idiopathic diabetes insipidus in childhood, even if no other family members are affected.

OBJECTIVE

Therapeutic strategies to enhance the efficacy of radioimmunotherapy have not been explored. Motexafin gadolinium is a novel anticancer agent that targets redox-dependent pathways and enhances sensitivity of tumor cells to ionizing radiation.

METHODS

We did preclinical studies examining motexafin gadolinium combined with rituximab and/or radiation in lymphoma cells. We subsequently completed a phase I clinical trial combining escalating doses of motexafin gadolinium concurrently with standard [(90)Y]ibritumomab tiuxetan for patients with relapsed/refractory non-Hodgkin's lymphoma.

RESULTS

In HF1 lymphoma cells, motexafin gadolinium and rituximab resulted in synergistic cytotoxicity (combination index, 0.757) through a mitochondrial-mediated caspase-dependent pathway, whereas cell death in Ramos and SUDHL4 cells was additive. Motexafin gadolinium/rituximab combined with radiation (1-3 Gy) resulted in additive apoptosis. Twenty-eight of 30 patients were evaluable on the phase I clinical trial. Median age was 65 years (47-87 years), and histologies were marginal-zone (n = 1), mantle-cell (n = 3), diffuse large cell (n = 6), and follicular lymphoma (n = 18). Of all patients, 86% were rituximab refractory. Therapy was well tolerated, and no dose-limiting toxicity was seen. Overall response rate was 57% [complete remission (CR), 43%], with median time-to-treatment failure of 10 months (1-48+ months) and median duration-of-response of 17 months. Of note, all responses were documented at 4 weeks. Furthermore, in rituximab-refractory follicular lymphoma (n = 14), overall response rate was 86% (CR, 64%), with a median time-to-treatment failure of 14 months (2-48+ months).

CONCLUSIONS

This represents the first report of a novel agent to be combined safely concurrently with radioimmunotherapy. Furthermore, tumor responses with [(90)Y]ibritumomab tiuxetan/motexafin gadolinium were prompt with a high rate of CRs, especially in rituximab-refractory follicular lymphoma.