Association of Lower Urinary Tract Symptom Severity with Kidney Function among Community Dwelling Older Men

PURPOSE

Most international practice guidelines recommend screening for chronic kidney disease among older men with lower urinary tract symptoms. However, prior studies supporting these guidelines are insufficient due to incomplete assessments of kidney function and inadequate adjustment for confounding factors.

MATERIALS AND METHODS

We conducted a cross-sectional study among 5,530 American men older than 65 years in the multicenter Osteoporotic Fractures in Men Study. Chronic kidney disease was defined per international guidelines as estimated glomerular filtration rate less than 60 ml/minute/1.73 m2 based on serum creatinine or cystatin C, or urinary albumin-to-creatinine ratio 30 mg/gm or greater. Lower urinary tract symptoms were assessed with the American Urological Association Symptom Index. Associations were estimated using multivariable linear and modified Poisson regression models.

RESULTS

Chronic kidney disease prevalence was 16% among 5,530 men with serum creatinine, 24% among 1,504 men with serum cystatin C and 14% among 1,487 men with urinary albumin-to-creatinine measurements. Lower urinary tract symptoms were not associated with lower estimated glomerular filtration rate based on serum creatinine or cystatin C. Although symptom severity was modestly associated with a higher prevalence of chronic kidney disease in age/site adjusted analyses, confidence intervals were wide and associations using all 3 definitions were not statistically significant after adjustment for important confounders, including cardiovascular disease and analgesic use.

CONCLUSIONS

Lower urinary tract symptoms are not independently associated with multiple measures of kidney dysfunction or prevalence of chronic kidney disease among older community dwelling men. Our results do not support recommendations for kidney function testing among older men with lower urinary tract symptoms.

Association of Diet With Erectile Dysfunction Among Men in the Health Professionals Follow-up Study

IMPORTANCE

Erectile dysfunction, especially in younger men, is an early sign of cardiovascular disease and may decrease quality of life. Men may be motivated to adopt a healthy dietary pattern if it lowers their risk of erectile dysfunction.

OBJECTIVE

To assess the association between adherence to a diet quality index based on healthy dietary patterns and erectile dysfunction in men.

DESIGN, SETTING, AND PARTICIPANTS

This population-based prospective cohort study included men from the Health Professionals Follow-up Study with follow-up from January 1, 1998, through January 1, 2014. Participants included US male health professionals aged 40 to 75 years at enrollment. Men with erectile dysfunction or a diagnosis of myocardial infarction, diabetes, stroke, or genitourinary cancer at baseline were excluded. Analyses were completed in February 2020.

EXPOSURES

A food frequency questionnaire was used to determine nutrient and food intake every 4 years.

MAIN OUTCOMES AND MEASURES

Diet quality was assessed by Mediterranean Diet score and the Alternative Healthy Eating Index 2010 score, with higher scores indicating healthier diet. Dietary index scores were cumulatively updated from 1986 until men developed erectile dysfunction, cardiovascular disease, died, or were lost to follow-up. Incident erectile dysfunction was assessed with questionnaires in 2000, 2004, 2008, and 2012. Hazard ratios (HRs) by prespecified categories or quintiles of dietary index scores were estimated using Cox proportional hazards regression analyses stratified by age.

RESULTS

Among 21 469 men included in analysis, mean (SD) age at baseline was 62 (8.4) years. During a mean (SD) follow-up of 10.8 (5.4) years and 232 522 person-years, there were 968 incident erectile dysfunction cases among men younger than 60 years, 3703 cases among men aged 60 to less than 70 years, and 4793 cases among men aged 70 years or older. Men younger than 60 years and in the highest category of the Mediterranean Diet score had the lowest relative risk of incident erectile dysfunction compared with men in the lowest category (HR, 0.78; 95% CI, 0.66-0.92). Higher Mediterranean diet scores were also inversely associated with incident erectile dysfunction among older men (age 60 to <70 years: HR, 0.82; 95% CI, 0.76-0.89; age ≥70 years: HR, 0.93; 95% CI, 0.86-1.00). Men scoring in the highest quintile of the Alternative Healthy Eating Index 2010 also had a lower risk of incident erectile dysfunction, particularly among men age younger than 60 years (quintile 5 vs quintile 1: HR, 0.78; 95% CI, 0.63-0.97).

CONCLUSIONS AND RELEVANCE

This cohort study found that adherence to healthy dietary patterns was associated with a lower risk for erectile dysfunction, suggesting that a healthy dietary pattern may play a role in maintaining erectile health.

Association Between Lower Urinary Tract Symptoms and Frailty in Older Men Presenting for Urologic Care

OBJECTIVE

To evaluate the association between non-neurogenic lower urinary tract symptoms (LUTS) and frailty among treatment-seeking older men.

METHODS

This is a cross-sectional study of male patients age 65 years and older presenting to an academic urology practice between December 2015 and March 2019. Men with cancer, neurologic disease, indwelling catheter, or continuous leakage were excluded. Participants completed a Timed-Up-and-Go-Test (TUGT) which was used to categorize men as fast (≤10 seconds), intermediate (11-14 seconds), or slow (≥15 seconds). Participants with the following diagnoses were identified using billing codes extracted from the electronic medical record: overactive bladder (OAB), benign prostatic hyperplasia (BPH), mixed OAB/BPH, or non-LUTS urologic condition. Multivariable associations were evaluated using multinomial logistic regression models adjusted for age, race, and body mass index.

RESULTS

Among 2206 men included in our sample, 64% were fast (mean TUGT time: 8.3 ± 1.2 seconds), 25% were intermediate (mean TUGT time: 12.0 ± 1.0 seconds), and 11% were slow (mean TUGT time: 18.5 ± 4.7 seconds). Subjects with slow TUGT times were more likely to be older, non-White, and have LUTS. Compared to non-LUTS conditions, OAB (odds ratio [OR] = 2.62, 95% CI 1.74, 3.93), BPH (OR = 1.70, 95% 1.14, 2.55), and mixed OAB/BPH (OR = 1.82, 95% 1.14, 2.92) were all associated with increased odds of slow TUGT time. LUTS diagnosis was not significantly associated with intermediate TUGT time.

CONCLUSION

LUTS diagnosis, particularly OAB, is associated with increased odds of slow TUGT time, a surrogate of frailty, compared to non-LUTS conditions. Frailty is common among older men with LUTS and should be considered during the initial urological evaluation.

PERSONAL: Feasibility Study Protocol for Placebo-Controlled, Randomized n-of-1 Trials of Tamsulosin for Lower Urinary Tract Symptoms

Background: Lower urinary tract symptoms (LUTS) affect more than half of men over age 70 and contribute to both poor health-related quality of life and polypharmacy. Tamsulosin hydrochloride, a selective α₁-blocker, is the most common medication used to treat LUTS due to presumed benign prostatic hyperplasia and is often prescribed indefinitely, although not all men benefit from long-term therapy. N-of-1 trials allow for individualized estimates of benefit and harm and could facilitate decisions regarding chronic tamsulosin therapy for LUTS, particularly among older men. Our team developed the PERSONAL (PlacEbo-controlled, Randomized, patient-Selected Outcomes, N-of-1 triALs) app to track daily urinary symptoms and medication side effects for n-of-1 trials among older men with LUTS.

Materials and Methods: We will conduct a feasibility study of 20 individual randomized n-of-1 trials using the PERSONAL app to compare tamsulosin (0.4 or 0.8 mg) vs. placebo among older men taking tamsulosin for LUTS. We will include men over age 65 with a smartphone for whom temporary discontinuation of tamsulosin is safe, (e.g., no history of acute retention). Participants will work with research staff to prospectively identify the most important urinary symptoms and medication side effects that they would like to digitally track. Men will then be randomized to 2-week treatment periods of tamsulosin or placebo followed by a 1-week wash-out with placebo, for 4 distinct treatment periods and 3 wash-out periods, totaling 11 weeks. Study medications will be blinded using over-encapsulation of tamsulosin pills and matching placebo. Our primary outcomes for this study will be recruitment and retention of eligible men, completion rates of n-of-1 trials and daily questionnaires using the PERSONAL app, and participants' perceived usefulness of their n-of-1 trial for determining whether tamsulosin is effective for them. Linear mixed effects models with individual-specific intercepts and intervention effects will also be used to estimate within-individual effects of tamsulosin.

Discussion: The goal of this innovative study is to establish feasibility and acceptability of using a mobile health app and n-of-1 trials to provide older men with individualized estimates of benefits and harms of chronic tamsulosin therapy for LUTS.

Mediterranean diet after prostate cancer diagnosis and urinary and sexual functioning: The health professionals follow-up study

BACKGROUND

Men with prostate cancer often experience urinary and sexual dysfunction after treatment. Previous studies have demonstrated a relationship between dietary factors and these symptoms among men with diabetes or metabolic syndrome. However, there are limited data on whether diet after prostate cancer diagnosis, including a Mediterranean dietary pattern, affects urinary and sexual function among prostate cancer survivors.

METHODS

Men diagnosed with non-metastatic prostate cancer in the Health Professionals Follow-up Study (n = 2960) from 1986 to 2012 were prospectively followed for a median of 8.3 years after treatment. Participants completed validated dietary questionnaires every 4 years and a health-related quality of life assessment in 2010 or 2012. We used generalized linear models to examine associations between post-diagnosis Mediterranean Diet Score (including individual score components and dietary fat subtypes) and quality of life domains (sexual functioning, urinary irritation/obstruction, urinary incontinence) assessed using the Expanded Prostate Cancer Index Composite Short Form (score 0-100; higher scores indicate better function).

RESULTS

No statistically significant relationships were observed between the Mediterranean Diet Score after prostate cancer diagnosis and urinary or sexual function. However, the associations did vary depending on pre-diagnosis urinary and sexual dysfunction for urinary irritation/obstruction and sexual function scores, respectively (P-interactions < 0.0001). Men with higher post-diagnosis vegetable intake reported higher urinary incontinence scores (72 vs 76 comparing lowest to highest quintile; P-trend = 0.003). Similarly, higher vegetable intake and lower polyunsaturated fat intake were associated with higher urinary irritation/obstruction scores (vegetable: 80 vs 84 comparing lowest to highest quintile, P-trend = 0.01; polyunsaturated fat: 84 vs 78 comparing lowest to highest quintile, P-trend = 0.005), however these associations were observed only among men with urinary symptoms prior to their prostate cancer diagnosis.

CONCLUSIONS

Among men with prostate cancer, diet intake after diagnosis was not significantly associated with urinary or sexual function, although some relationships appeared to differ among men with and without symptoms prior to their prostate cancer diagnosis. Higher vegetable intake and lower polyunsaturated fat intake after prostate cancer diagnosis may be associated with better urinary function. However, this analysis was exploratory, and further research is needed to better delineate these relationships and guide dietary recommendations for men with prostate cancer.

Predictors of higher-risk chronic opioid prescriptions in an academic primary care setting

BACKGROUND

Patients with chronic noncancer pain treated with higher doses of opioids or concurrent substance use are at increased risk of adverse events. Although several national guidelines recommend maximum dosing thresholds and urine drug testing, adherence to these guidelines is inconsistent.

METHODS

To identify predictors of higher-risk opioid prescriptions in 2 academic primary care clinics, the authors developed a retrospective cohort of 842 patients who were prescribed ≥5 opioid prescriptions for noncancer pain between March 2012 and March 2013. The authors evaluated odds of higher-dose opioid prescriptions and urine drug testing using multivariate logistic models.

RESULTS

Among study subjects, 47% received prescriptions for the equivalent of ≥50 mg morphine per day. After adjustment for confounders, patients with a resident primary care provider were less likely to receive higher-dose prescriptions compared with faculty providers (odds ratio = 0.66, 95% confidence interval [CI]: 0.46-0.94), whereas patients with a nonlocal home address were more likely to be prescribed higher doses (odds ratio = 2.1, 95% CI: 1.5-2.9). Hispanic, Asian, and older patients were also less likely to be prescribed higher doses. Urine drug testing was not regularly completed (35% over 2 years), but odds of testing were higher for patients who self-identified as black, had resident primary care providers, lived locally, or were prescribed higher opioid doses.

CONCLUSIONS

In this academic clinical setting, patients with a resident primary care provider are less likely to receive higher-risk opioid prescriptions, as are Hispanic, Asian, and older patients. Black patients complete urine drug tests more frequently independent of other patient and provider characteristics. Additional studies are needed to assess why patients who travel larger distances to their primary care clinic are prescribed higher doses of opioids for chronic noncancer pain.

Geographic Disparities in Access to Agencies Providing Income-Related Social Services

Geographic location is an important factor in understanding disparities in access to health-care and social services. The objective of this cross-sectional study is to evaluate disparities in the geographic distribution of income-related social service agencies relative to populations in need within Boston. Agency locations were obtained from a comprehensive database of social services in Boston. Geographic information systems mapped the spatial relationship of the agencies to the population using point density estimation and was compared to census population data. A multivariate logistic regression was conducted to evaluate factors associated with categories of income-related agency density. Median agency density within census block groups ranged from 0 to 8 agencies per square mile per 100 population below the federal poverty level (FPL). Thirty percent (n = 31,810) of persons living below the FPL have no access to income-related social services within 0.5 miles, and 77 % of persons living below FPL (n = 83,022) have access to 2 or fewer agencies. 27.0 % of Blacks, 30.1 % of Hispanics, and 41.0 % of non-Hispanic Whites with incomes below FPL have zero access. In conclusion, some neighborhoods in Boston with a high concentration of low-income populations have limited access to income-related social service agencies.

Selenoprotein and antioxidant genes and the risk of high-grade prostate cancer and prostate cancer recurrence

BACKGROUND

Observational studies suggest an inverse association between selenium and risk of prostate cancer. However, randomized controlled trials of selenium supplementation have reported conflicting results. Thus, we examined plasma selenium and selenium-related genes in relation to risk of high-grade prostate cancer and prostate cancer recurrence among men initially diagnosed with non-metastatic disease.

METHODS

We measured plasma selenium and genotyped 73 single nucleotide polymorphisms in TXNRD1, TXNRD2, GPX1, GPX3, GPX4, SEP15, SEPP1, SELENBP1, OGG1, and CAT among 568 men with non-metastatic prostate cancer who underwent radical prostatectomy. We examined associations between plasma selenium, genotypes, and risk of high-grade prostate cancer (Gleason grade ≥8 or 7 with primary score ≥4; n = 111) using logistic regression, and risk of prostate cancer recurrence (61 events; 3.8 y median follow-up) using Cox proportional hazards regression.

RESULTS

Plasma selenium was not associated with risk of high-grade prostate cancer or prostate cancer recurrence. Less common alleles of rs11913319 in TXNRD2 and rs125701 in OGG1 were associated with an increased risk of high-grade prostate cancer. We observed associations between the risk of prostate cancer recurrence and multiple SNPs in TXNRD1, TXNRD2, GPX3, and SEP15. These associations were no longer statistically significant after adjustment for multiple comparisons.

CONCLUSIONS

Among men with non-metastatic prostate cancer, there is suggestive evidence that genetic variation in selenoproteins and related antioxidant enzymes may be associated with risk of high-grade disease at diagnosis and prostate cancer recurrence.

Antioxidant and vitamin E transport genes and risk of high-grade prostate cancer and prostate cancer recurrence

BACKGROUND

Observational studies suggest an inverse association between vitamin E and risk of prostate cancer, particularly aggressive tumors. However, three large randomized controlled trials have reported conflicting results. Thus, we examined circulating vitamin E and vitamin E-related genes in relation to risk of high-grade prostate cancer and prostate cancer recurrence among men initially diagnosed with clinically organ-confined disease.

METHODS

We measured circulating α- and γ-tocopherol and genotyped 30 SNPs in SOD1, SOD2, SOD3, TTPA, and SEC14L2 among 573 men with organ-confined prostate cancer who underwent radical prostatectomy. We examined associations between circulating vitamin E, genotypes, and risk of high-grade prostate cancer (Gleason grade ≥ 8 or 7 with primary score ≥ 4; n = 117) using logistic regression, and risk of recurrence (56 events; 3.7 years median follow-up) using Cox proportional hazards regression.

RESULTS

Circulating γ-tocopherol was associated with an increased risk of high-grade prostate cancer (Q4 v. Q1 odds ratio [OR] = 1.87; 95% confidence intervals [CI]: 0.97-3.58; P trend =0.02). The less common allele in SOD3 rs699473 was associated with an increased risk of high-grade disease (T > C: OR = 1.40, 95% CI: 1.04-1.89). Two independent SNPs in SOD1 were inversely associated with prostate cancer recurrence in additive models (rs17884057 hazard ratio [HR] = 0.49, 95%CI: 0.25-0.96; rs9967983 HR = 0.62, 95% CI: 0.40-0.95).

CONCLUSIONS

Among men with clinically organ-confined prostate cancer, genetic variation in SOD may be associated with risk of high-grade disease at diagnosis and disease recurrence. Circulating γ-tocopherol levels may also be associated with an increased risk of high-grade disease at diagnosis.

Plasma vitamin D levels, menopause, and risk of breast cancer: dose-response meta-analysis of prospective studies

Previous evidence suggests that higher circulating 25-hydroxyvitamin D (25[OH]D) levels are variably associated with lower breast cancer risk; however, prospective studies and clinical trials have been inconsistent, particularly between older and younger women of differing menopausal status. We conducted a quantitative nonlinear dose-response meta-analysis of prospective studies evaluating the association between circulating 25(OH)D and breast cancer risk, stratified by menopause. A systematic search of MEDLINE and EMBASE included studies published through May 2011. We reviewed references from retrieved articles and contacted relevant investigators for additional data from prospective studies on circulating 25(OH)D levels and incident breast cancers. Prospective studies of circulating vitamin D and breast cancer risk were reviewed, and no language restrictions were imposed. Information on study population, menopausal status, 25(OH)D levels, and relative risk (RR) estimates were extracted using a standardized protocol.A total of 9 prospective studies were included, comprising 5206 cases and 6450 controls. Data were pooled using dose-response random-effects meta-regression models. Identifying nonlinear effects, spline models were optimized for thresholds. The relationship between circulating 25(OH)D and breast cancer risk differed by menopausal status (p = 0.05 for effect modification). While no association was found in premenopausal women, dose-response modeling revealed a nonlinear inverse association among postmenopausal women. Notably, a flat association was observed in the lowest range of 25(OH)D levels <27 ng/mL (RR = 1.01 per 5 ng/mL; 95% confidence interval [CI], 0.98-1.04). In contrast, postmenopausal breast cancer risk decreased with 25(OH)D levels 27-<35 ng/mL (p = 0.02 for nonlinear risk change), where a 5 ng/mL increase in 25(OH)D was associated with a 12% lower risk of breast cancer (RR = 0.88 per 5 ng/mL; 95% CI, 0.79-0.97), with suggestive flattening at higher doses >35 ng/mL. The significant inverse association did not appear to vary across strata of invasive/in-situ cases, body mass index adjustment, region, postmenopausal hormone use, or assay method.In summary, this dose-response meta-analysis of prospective studies of plasma 25(OH)D suggested a breast cancer risk differential by menopause, whereby a step-wise inverse association was observed beyond a threshold of 27 ng/mL, but with flattening of effects above 35 ng/mL, in postmenopausal women. These findings help resolve prior inconsistent findings and may carry important clinical and public health implications.

Abstract 77: Analgesic use in relation to sex hormone and prolactin concentrations in premenopausal women

The use of common analgesics, such as aspirin, non-aspirin NSAIDs and acetaminophen, may be associated with the risk of several hormone-related cancers, possibly via effects on sex hormone and prolactin concentrations. Therefore, we assessed the cross-sectional relationship between analgesic (aspirin, non-aspirin NSAIDS, and acetaminophen) use and sex hormone and prolactin concentrations among 2,034 premenopausal women, 32 to 54 years old, from the Nurses' Health Study II. Approximately 84% of women provided timed luteal and follicular blood samples; the remainder provided a single untimed sample. After adjustment for age, BMI, parity, and other potential confounders, acetaminophen use was inversely associated with prolactin levels (ptrend= 0.04). Compared to non-users, prolactin concentrations were 11.8% lower among women who reported using acetaminophen at least 2 times per week (p&lt;0.01). Similarly, acetaminophen was inversely associated with free testosterone, when comparing use at least 2 times per week to non-users (7.1% lower, p = 0.04; ptrend= 0.04). Use of non-aspirin NSAIDs was positively associated with follicular free estradiol, with 13.5% higher levels in women who reported use 4 or more days per week as compared to non-users (p = 0.04; ptrend= 0.11); results for free follicular estradiol were similar (13.2% higher, p = 0.06; ptrend= 0.11) though not statistically significant. There were no clear associations observed between analgesic use and luteal estradiol, estrone, estrone sulfate, DHEA, DHEAS, androstenedione, and estrogen/androgen ratios. After adjustment for multiple comparisons, none of the associations were statistically significant. In conclusion, our study provides modest evidence for an association of acetaminophen use with prolactin and free testosterone concentrations in premenopausal women, and the suggestion of an association between non-aspirin NSAIDs and follicular free estradiol among those with frequent use.

Citation Format: Scott R. Bauer, Renee T. Fortner, Margaret A. Gates, Heather Eliassen, Susan E. Hankinson, Shelley S. Tworoger. Analgesic use in relation to sex hormone and prolactin concentrations in premenopausal women. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr 77.

Statin use and risk of prostate cancer in the prospective Osteoporotic Fractures in Men (MrOS) Study

BACKGROUND

Statins are a common medication for cholesterol control that may also have effects on cancer-related pathways. The evidence of an association between statins and prostate cancer risk remains ambiguous.

METHODS

We examined statin use in a prospective cohort of 5,069 elderly U.S. men and the risk of incident total, low/high stage, and low/high grade prostate cancer diagnosed between 2000 and 2008. We used multivariate logistic regression models to estimate relative risks and 95% confidence intervals, adjusting for demographic and lifestyle characteristics.

RESULTS

There was no evidence of an association between statin use and any of the prostate cancer endpoints (total, low/high stage, low/high grade prostate cancer), adjusting for age, study site, race, body mass index, marital status, family history of prostate cancer, number of comorbidities, physical activity, and smoking history.

CONCLUSIONS AND IMPACT

In this study of elderly U.S. men, we observed a null association between statin use and risk of prostate cancer.

The TMPRSS2:ERG rearrangement, ERG expression, and prostate cancer outcomes: a cohort study and meta-analysis

BACKGROUND

Whether the genomic rearrangement transmembrane protease, serine 2 (TMPRSS2):v-ets erythroblastosis virus E26 oncogene homolog (ERG) has prognostic value in prostate cancer is unclear.

METHODS

Among men with prostate cancer in the prospective Physicians' Health and Health Professionals Follow-Up Studies, we identified rearrangement status by immunohistochemical assessment of ERG protein expression. We used Cox models to examine associations of ERG overexpression with biochemical recurrence and lethal disease (distant metastases or cancer-specific mortality). In a meta-analysis including 47 additional studies, we used random-effects models to estimate associations between rearrangement status and outcomes.

RESULTS

The cohort consisted of 1,180 men treated with radical prostatectomy between 1983 and 2005. During a median follow-up of 12.6 years, 266 men experienced recurrence and 85 men developed lethal disease. We found no significant association between ERG overexpression and biochemical recurrence [hazard ratio (HR), 0.99; 95% confidence interval (CI), 0.78-1.26] or lethal disease (HR, 0.93; 95% CI, 0.61-1.43). The meta-analysis of prostatectomy series included 5,074 men followed for biochemical recurrence (1,623 events), and 2,049 men followed for lethal disease (131 events). TMPRSS2:ERG was associated with stage at diagnosis [risk ratio (RR)(≥T3 vs. T2), 1.23; 95% CI, 1.16-1.30) but not with biochemical recurrence (RR, 1.00; 95% CI, 0.86-1.17) or lethal disease (RR, 0.99; 95% CI, 0.47-2.09).

CONCLUSIONS

These results suggest that TMPRSS2:ERG, or ERG overexpression, is associated with tumor stage but does not strongly predict recurrence or mortality among men treated with radical prostatectomy.

IMPACT

This is the largest prospective cohort study to examine associations of ERG overexpression and lethal prostate cancer among men treated with radical prostatectomy.

Flavonoid-rich cocoa consumption affects multiple cardiovascular risk factors in a meta-analysis of short-term studies

A growing body of evidence suggests that the consumption of foods rich in polyphenolic compounds, particularly cocoa, may have cardioprotective effects. No review, however, has yet examined the effect of flavonoid-rich cocoa (FRC) on all major cardiovascular risk factors or has examined potential dose-response relationships for these effects. A systematic review and meta-analysis of randomized, controlled trials was performed to evaluate the effect of FRC on cardiovascular risk factors and to assess a dose-response relationship. Inclusion and exclusion criteria as well as dependent and independent variables were determined a priori. Data were collected for: blood pressure, pulse, total cholesterol, HDL cholesterol, LDL cholesterol, TG, BMI, C-reactive protein, flow-mediated vascular dilation (FMD), fasting glucose, fasting insulin, serum isoprostane, and insulin sensitivity/resistance indices. Twenty-four papers, with 1106 participants, met the criteria for final analysis. In response to FRC consumption, systolic blood pressure decreased by 1.63 mm Hg (P = 0.033), LDL cholesterol decreased by 0.077 mmol/L (P = 0.038), and HDL cholesterol increased by 0.046 mmol/L (P = 0.037), whereas total cholesterol, TG, and C-reactive protein remained the same. Moreover, insulin resistance decreased (HOMA-IR: -0.94 points; P < 0.001), whereas FMD increased (1.53%; P < 0.001). A nonlinear dose-response relationship was found between FRC and FMD (P = 0.004), with maximum effect observed at a flavonoid dose of 500 mg/d; a similar relationship may exist with HDL cholesterol levels (P = 0.06). FRC consumption significantly improves blood pressure, insulin resistance, lipid profiles, and FMD. These short-term benefits warrant larger long-term investigations into the cardioprotective role of FRC.

Proton pump inhibitors and risk of fractures: a meta-analysis of 11 international studies

BACKGROUND

Concerns have been raised about the risk of fractures with acid-suppressive medications, such as proton pump inhibitors and histamine(2)-receptor antagonists.

METHODS

This meta-analysis evaluated the association between proton pump inhibitor or histamine(2)-receptor antagonist use and fractures. We performed a systematic search of published literature (1970 to October 10, 2010) in MEDLINE, EMBASE, and other sources. Ten publications reporting 11 studies were considered eligible for analysis.

RESULTS

All studies were observational case-control or cohort studies and primarily evaluated older adults. The summary effect estimate for risk of hip fracture increased modestly among individuals taking proton pump inhibitors (relative risk [RR] 1.30, 95% confidence interval [CI], 1.19-1.43). There also was an increase in spine (RR 1.56, 95% CI, 1.31-1.85) and any-site fractures (RR 1.16, 95% CI, 1.04-1.30) among proton pump inhibitor users. These findings were similar in both men and women and after stratification by duration of use. In contrast, histamine(2)-receptor antagonist use was not significantly associated with increased risk of hip fracture (RR 1.12, 95% CI, 0.97-1.30).

CONCLUSION

In this meta-analysis of observational studies, proton pump inhibitors modestly increased the risk of hip, spine, and any-site fractures, whereas histamine(2)-receptor antagonists were not associated with fracture risk. The possibility of residual confounding cannot be excluded. Further skeletal evaluation should be considered for patients who are taking proton pump inhibitors and also at risk for osteoporotic fracture.

Localization of recombination activating gene 1/green fluorescent protein (RAG1/GFP) expression in secondary lymphoid organs after immunization with T-dependent antigens in rag1/gfp knockin mice

Secondary rearrangements of immunoglobulin gene segments that generate a new antibody repertoire in peripheral B cells have been described as receptor revision and occur by as yet unknown mechanisms. To determine the importance of recombination activating gene (RAG) expression in receptor revision, heterozygous rag1/green fluorescent protein (gfp) knockin mice were used to examine the location of RAG1 expression in the germinal centers (GCs) of lymphoid follicles after immunization with a variety of T-cell-dependent antigens. Immunization of rag1/gfp heterozygous mice or rag1 homozygous knockout mice reconstituted with rag1/gfp heterozygous spleen cells caused the down-regulation of RAG1/GFP signal in GCs. Although some RAG1/GFP(+) cells appeared in regions surrounding the peanut agglutinin (PNA)(+)GL-7(+) GC area, RAG1/GFP(+) cells did not accumulate in the central region. In addition, the stimulation of spleen B cells with anti-mu antibody plus interleukin-4 (IL-4) or with anti-CD40 monoclonal antibody plus IL-7 did not induce GFP signals at detectable levels in vitro. These results clearly demonstrate that RAG1 re-expression either does not occur or is at extremely low levels in antigen-driven B cells in GCs of secondary lymphoid follicles, suggesting that other mechanisms may mediate the gene rearrangements observed in receptor revision.

Interaction of abl and raf with IL-7 signaling pathway and transformation of pre-B cells from resistant mice

After in vivo inoculation with abl/myc- and raf/myc-containing retroviruses, BALB/c mice predominantly develop late stage B cell tumors (plasmacytomas) and less frequently develop earlier B-lineage tumors while DBA/2 mice do not develop B-lineage tumors. We have investigated the in vitro tumorigenic potential of these viruses using cultured normal pre-B cell lymphocytes from both BALB/c and DBA/2 mice. Interestingly, both viruses infect cultured pre-B lymphocytes from both mouse strains. Following infection, IL-7 dependent pre-B cells become independent of normal in vitro growth requirements within 24 h and can rapidly form in vivo pre-B lymphomas in both mouse strains. Mechanisms mediating loss of IL-7 dependence are different depending on whether the raf or abl gene is present in myc-containing viruses. IL-7 JAK-STAT signaling is constitutively active in abl/myc induced pre-B cell tumors. In contrast, IL-7 JAK-STAT signaling is not constitutive in raf/myc induced pre-B cell tumors, demonstrating that subversion of this component of IL-7 signal transduction is not obligatory for pre-B cell transformation or loss of IL-7 dependence.

Modulated expression of the epidermal growth factor-like homeotic protein dlk influences stromal-cell-pre-B-cell interactions, stromal cell adipogenesis, and pre-B-cell interleukin-7 requirements

A close relationship exists between adipocyte differentiation of stromal cells and their capacity to support hematopoiesis. The molecular basis for this is unknown. We have studied whether dlk, an epidermal growth factor-like molecule that intervenes in adipogenesis and fetal liver hematopoiesis, affects both stromal cell adipogenesis and B-cell lymphopoiesis in an established pre-B-cell culture system. Pre-B-cell cultures require both soluble interleukin-7 (IL-7) and interactions with stromal cells to promote cell growth and prevent B-cell maturation or apoptosis. We found that BALB/c 3T3 fibroblasts express dlk and function as stromal cells. Transfection of these cells with antisense dlk decreased dlk expression and increased insulin-induced adipocytic differentiation. When antisense transfectants were used as stroma, IL-7 was no longer required to support the growth of pre-B cells and prevent maturation or apoptosis. Antisense dlk transfectants of S10 stromal cells also promoted pre-B-cell growth in the absence of IL-7. These results show that modulation of dlk on stromal cells can influence their adipogenesis and the IL-7 requirements of the pre-B cells growing in contact with them. These results indicate that dlk influences differentiation signals directed both to the stromal cells and to the lymphocyte precursors, suggesting that dlk may play an important role in the bone marrow hematopoietic environment.