Silvina Levis

University of Miami Miller School of Medicine, Miami, Florida, United States

Are you Silvina Levis?

Claim your profile

Publications (33)140.21 Total impact

  • Stuti Dang, Silvina Levis, Violet S Lagari
    Journal of Women s Health 03/2014; 23(3):278. · 1.42 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hypovitaminosis D has been associated with age-related physical decline and an increased risk for falls. The objective of this study is to test whether supplementation with 4,000 IU of vitamin D3 (vitD3) for 9 months will improve, or slow the decline of, the ability to perform physical tests which have been associated with the preservation of independence in sedentary older men. We describe the study design and the baseline characteristics of the 314 men screened in the VIVA-VA Study (Vitamin D In Vulnerable Adults in the VA), a 2-year, single-site, double-blind, placebo-controlled, randomized clinical trial that enrolled sedentary male veterans ages 65 to 95. The main inclusion criteria are 25-OH vitamin D (25-OHD) levels between 10 and 30 ng/ml, and a Short Performance Physical Battery (SPPB) score ≤ 9. The primary outcome of the study is the SPPB. Subjects were recruited from the Miami Veterans Medical Center clinics. The study recruited 314 male veterans of multiethnic backgrounds. The baseline characteristics observed of the 314 men screened in the VIVA-VA Study are consistent with what is expected in a cohort of elderly sedentary men: low physical performance scores, and low 25OHD levels despite living in South Florida. The results of this study that uses a high dose of vitamin D in a cohort of sedentary older men could provide an evidence-based indication for vitamin D supplementation to improve physical performance in this population.
    Contemporary Clinical Trials. 01/2014;
  • Violet S Lagari, Silvina Levis
    [Show abstract] [Hide abstract]
    ABSTRACT: Postmenopausal osteoporosis is a condition associated with low bone mass resulting from the increased bone resorption that occurs following a decline in estrogen levels. Phytoestrogens are plant-derived compounds that have affinity to the estrogen receptor and are able to act as either estrogen agonists or antagonists. Because of their structural similarity to 17-beta-estradiol, they have been studied extensively for their role in the prevention of postmenopausal bone loss. An extensive number of studies employing different types of isoflavone preparations (including soy foods, soy-enriched foods, and soy isoflavone tablets) have been conducted in a wide range of populations, including Western and Asian women. Although there is considerable variability in study design and duration, study population, type of soy isoflavone employed in the intervention, and study outcomes, the evidence points to a lack of a protective role of soy isoflavones in the prevention of postmenopausal bone loss.
    Journal of Clinical Densitometry 09/2013; · 1.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: There is an ongoing debate over the role of serum 25(OH) vitamin D [25(OH)D] levels in maintaining or improving physical performance and muscle strength. Much of the controversy is due to the variability between studies in participants' characteristics, baseline serum 25(OH)D levels, and baseline physical functioning. The aim of this ancillary study conducted within a randomized controlled clinical trial was to investigate whether supplementation with 400 or 2000 IU vitamin D3 daily for 6 months would improve measures of physical performance and muscle strength in a community-dwelling elderly population aged 65 to 95. Those with the slowest gait speed improved their ability to do chair-stand tests after vitamin D supplementation. This finding remained significant after controlling for potential confounding variables. There was also an inverse correlation between serum 25(OH)D levels and fat mass index (FMI) among women, suggesting that higher supplementation with vitamin D is needed as weight increases. The results of this study suggest that supplementation with vitamin D may be most beneficial in older populations who have low baseline physical functioning. © 2013 American Society for Bone and Mineral Research.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 04/2013; · 6.04 Impact Factor
  • Violet S Lagari, Silvina Levis
    [Show abstract] [Hide abstract]
    ABSTRACT: Women have always looked for non-hormonal options to alleviate menopausal vasomotor symptoms and prevent menopausal bone loss. The use of complementary and alternative medicine for these purposes has particularly increased after the publication of the Women's Health Initiative's results suggesting that there might be more risks than benefits with hormone replacement. Phytoestrogens are plant-derived estrogens that, although less potent than estradiol, bind to the estrogen receptor and can function as estrogen agonists or antagonists. Soy isoflavones extracted from soy are the phytoestrogens most commonly used by menopausal women. Because typical Western diets are low in phytoestrogens and taking into account the general difficulty in changing dietary habits, most clinical trials in Western women have used isoflavone-fortified foods or isoflavone tablets. Although some women might experience a reduction in the frequency or severity of hot flashes, most studies point towards the lack of effectiveness of isoflavones derived from soy or red clover, even in large doses, in the prevention of hot flashes and menopausal bone loss.
    The Journal of steroid biochemistry and molecular biology 12/2012; · 3.98 Impact Factor
  • Silvina Levis, Violet S. Lagari
    [Show abstract] [Hide abstract]
    ABSTRACT: Diet, a modifiable osteoporosis risk factor, plays an important role in the acquisition and maintenance of bone mass. The influence of diet on bone begins in childhood; even maternal diet can influence bone mass in the offspring. A good general nutritional status and adequate dietary protein, calcium, vitamin D, fruits, and vegetables have a positive influence on bone health, while a high caloric diet and heavy alcohol consumption have been associated with lower bone mass and higher rates of fracture. The evidence for a role of other minerals and vitamins in skeletal health is not as strong, but recent evidence suggests that vitamins C and K might also have an effect on bone.
    Current Osteoporosis Reports 09/2012; 10(4).
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective The adequate dose of vitamin D supplementation for community-dwelling elderly people has not been thoroughly investigated. This study aims to determine the efficacy of a low-dose and a higher dose of vitamin D3 in maintaining 25 hydroxyvitamin D [25(OH)D] levels at or above 30 ng/ml.Methods This was a single site, double-blind, randomized exploratory clinical trial that enrolled adults aged 65 and older. Within strata of baseline 25(OH)D levels (< 30 vs. ≥ 30 ng/ml) subjects were randomized in a 1:2 ratio to receive either 400 or 2,000 IU vitamin D3 daily for 6 months. The main outcome measures were changes in serum 25(OH)D levels according to baseline 25(OH)D levels and dose of vitamin D3.Results At baseline, 39% (41/105) of participants had low 25(OH)D levels (< 30 ng/ml). After 6 months of vitamin D3 supplementation, 66% (21/32) of the participants on 400 IU and 24% (14/59) of the participants on 2,000 IU of vitamin D3 still had low 25(OH)D levels. The largest increases in serum 25(OH)D levels were observed in subjects with baseline levels < 30 ng/ml who received 2,000 IU of vitamin D daily.Conclusions Regardless of baseline 25(OH)D level, in persons aged 65 and older, 6-month vitamin D3 supplementation with 400 IU daily resulted in low 25(OH)D in most individuals, while 2,000 IU daily maintained 25(OH)D levels within an acceptable range in most people on this regimen.
    Endocrine Practice 07/2012; · 2.49 Impact Factor
  • Silvina Levis, George Theodore
    [Show abstract] [Hide abstract]
    ABSTRACT: In 2007, the Agency for Healthcare Research and Quality(AHRQ) published a systematic review on the comparative effectiveness of treatments for osteoporosis. The review included studies on the benefits and risks of medications and therapies used to prevent fractures in postmenopausal women and men with low bone density (osteopenia) or osteoporosis. Factors that may affect adherence to treatment, and monitoring for the identification of those most likely to benefit from treatment were also included in this review. AHRQ published an updated review in March 2012 that summarized the benefits and risks of osteoporosis medications in treatment and prevention of osteoporosis, including bisphosphonates (aledronate, risedronate, ibandronate, zoledronic acid), parathyroid hormone, teriparatide, calcitonin, estrogens (for prevention in postmenopausal women), selective estrogen receptor modulators (raloxifene), and denosumab(approved by the FDA in 2010). In addition, dietary and supplemental calcium and vitamin D, as well as weight-bearing exercise, for the preservation of bone mass and the decrease of fracture risk in patients with osteoporosis, were evaluated. To (a) familiarize health care professionals with the methods and findings from AHRQ's 2012 comparative effectiveness review on treatments to prevent fractures in men and women with low bone density or osteoporosis, (b) encourage consideration and application of the findings of this review in clinical and managed care settings, and (c) identify limitations and gaps in the existing research with respect to the benefits and risks of treatments for osteoporosis. Osteoporosis is a prevalent systemic skeletal disease caused by bone deterioration and loss of mass resulting in fractures, chronic pain and physical disability. It is common in postmenopausal women but men are at risk as well for fractures associated with low bone density. The increasing prevalence and cost of treating osteoporosis make the study of safety and effectiveness for currently available osteoporosis therapies pertinent and timely. In 2012, the Agency for Healthcare Research and Quality (AHRQ) published an updated review on the effectiveness and safety of treatments for osteoporosis, including new therapies for the prevention of vertebral and nonvertebral fractures in postmenopausal women and men.The interventions assessed in the review included 1 biological agent, pharmacological agents, dietary and supplemental calcium and vitamin D, and weight-bearing exercise. The updated report included the new agents and indications approved after the 2007 report and new data on effectiveness and adverse events associated with the bisphosponates; calcitonin was determined by the reviewers to not be appropriate therapy for osteoporosis and was excluded. The updated review examined 5 key questions focused on comparative review of all FDA-approved medicines for osteoporosis in fracture risk reduction, effectiveness in racial/ethnic subpopulations as well as different risk stratification using FRAX (World Health Organization Fracture Risk Assessment Tool) or other cutoffs, compliance and adherence, adverse effects of medications, the prediction of treatment efficacy using bone mineral density (BMD) monitoring by dual energy x-ray absorptiometry (DXA), and comparative effectiveness of long-term therapy.The AHRQ reviewers found high strength of evidence to support a reduction in risk of vertebral, nonvertebral and hip fractures in postmenopausal women with osteoporosis treated with 1 of 4 agents (alendronate, risedronate, zoledronic acid, or denosumab). A risk reduction for vertebral fractures in postmenopausal women with osteoporosis treated with ibandronate, teriparatide, or raloxifene therapy was supported with high-strength evidence. Evidence was graded high strength for reduction of vertebral and hip fracture with estrogen therapy in postmenopausal women but not in women with established osteoporosis. Evidence was graded moderate for a reduction in nonvertebral fractures with teriparatide or calcium monotherapy. Moderate or low-moderate strength of evidence showed that calcium alone does not reduce the risk of vertebral or nonvertebral fracture, and that vitamin D has mixed results on decreasing overall fracture risk. High-strength evidence supports a reduction in the risk of hip fracture with calcium treatment. Vitamin D treatment significantly reduced vertebral fractures among patients with primary osteoporosis. The combination of calcium plus vitamin C did not reduce vertebral fracture risk, but did reduce nonvertebral fracture risk in certain populations. Calcium plus vitamin D did decrease the risk of fracture in elderly women but not in elderly men. Adherence and persistence to osteoporosis medications varied depending on patient age, prior history of fracture, dosing frequency, concomitant use of other medications, and adverse effects. Adherence to treatment improved with weekly dosing compared with daily regimens, but evidence was lacking to show monthly regimens improved adherence over weekly regimens. This article recaps the key findings from the AHRQ 2012 review for the purpose of informing health care providers about the efficacy and safety of therapies used to prevent osteoporotic vertebral, nonvertebral, hip, and wrist fractures. Scientific literature on the effects of risk factors, adherence, BMD monitoring, and long-term therapy on patient outcomes is reviewed in order to inform prescribing decisions. In addition, applications of the AHRQ findings to practice are discussed to provide clinicians with information needed to provide evidence-based care for their patients.
    Journal of managed care pharmacy: JMCP 05/2012; 18(4 Suppl B):S1-15; discussion S13. · 2.41 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Concerns regarding the risk of estrogen replacement have resulted in a significant increase in the use of soy products by menopausal women who, despite the lack of evidence of the efficacy of such products, seek alternatives to menopausal hormone therapy. Our goal was to determine the efficacy of soy isoflavone tablets in preventing bone loss and menopausal symptoms. The study design was a single-center, randomized, placebo-controlled, double-blind clinical trial conducted from July 1, 2004, through March 31, 2009. Women aged 45 to 60 years within 5 years of menopause and with a bone mineral density T score of -2.0 or higher in the lumbar spine or total hip were randomly assigned, in equal proportions, to receive daily soy isoflavone tablets, 200 mg, or placebo. The primary outcome was changes in bone mineral density in the lumbar spine, total hip, and femoral neck at the 2-year follow-up. Secondary outcomes included changes in menopausal symptoms, vaginal cytologic characteristics, N -telopeptide of type I bone collagen, lipids, and thyroid function. After 2 years, no significant differences were found between the participants receiving soy tablets (n = 122) and those receiving placebo (n = 126) regarding changes in bone mineral density in the spine (-2.0% and -2.3%, respectively), the total hip (-1.2% and -1.4%, respectively), or the femoral neck (-2.2% and -2.1%, respectively). A significantly larger proportion of participants in the soy group experienced hot flashes and constipation compared with the control group. No significant differences were found between groups in other outcomes. In this population, the daily administration of tablets containing 200 mg of soy isoflavones for 2 years did not prevent bone loss or menopausal symptoms. clinicaltrials.gov Identifier: NCT00076050.
    Archives of internal medicine 08/2011; 171(15):1363-9. · 11.46 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Height and weight information is commonly used in clinical trials and in making therapeutic decisions in medical practice. In both settings, the data are often obtained by self-report. If erroneous, this practice could lead to inaccuracies in estimating renal function and medication doses or to inaccurate outcomes of research studies. Previous publications have reported lack of reliability of self-reported weight and height in the general population but have not addressed age-specific and ethnicity-specific subgroups in the U.S. population. The inaccuracy of self-reported weight and height could be particularly significant in times of considerable changes in body weight, such as at menopause, which is often associated with weight gain. We assessed the validity of self-reported height and weight in 428 women within the first 5 years of menopause, 70.6% of whom were Hispanic. Participants overestimated their height by 2.2±3.5 cm (mean±standard deviation [SD]) and underestimated their weight by 1.5±2.9 kg. As a group, based on self-reported measures, 33.3% were misclassified with respect to body mass index (BMI) category, and the difference between measured BMI and self-reported BMI was similar between Hispanic white and non-Hispanic white women, positively related to measured weight, and inversely related to measured height, years from menopause, and multiple parity. From the public health perspective, inaccurate self-report could lead to a considerable underestimation of the current obesity prevalence rates. In our study population, the prevalence of obesity (BMI ≥30 kg/m(2)) was 6.3% based on self-reported values and 18% based on measured height and weight, representing a 3-fold underestimation.
    Journal of Women s Health 03/2011; 20(4):599-604. · 1.42 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the prevalence of hypovitaminosis D (serum 25-hydroxyvitamin D<32 ng/mL; HVD) in a population of elderly veterans and conduct a preliminary assessment of the efficacy of supplementation with cholecalciferol in correcting HVD. Randomized, double-blind, placebo-controlled clinical trial. Geriatric clinic at the Bruce W. Carter Veterans Affairs Medical Center, Miami, Florida. Veterans aged 70 and older. Oral cholecalciferol 2,000 IU daily or placebo for 6 months. Serum calcium, 25-hydroxyvitamin D, parathyroid hormone, and 24-hour urinary calcium. Of the 34 participants who completed the study, 62% had HVD at baseline. In the treatment group, mean serum 25-hydroxyvitamin D level rose from 28.4±7.9 ng/mL at baseline to 42.7±10.5 ng/mL at the end of the trial, but levels remained less than 32 ng/mL in three of 17 (18%) of the participants. In the placebo group, the baseline level of 27.7±8.3 ng/mL remained unchanged (28.8±8.7 ng/mL). Supplementation did not alter serum or urinary calcium levels and did not result in any adverse events. These initial observations suggest that, in older veterans, cholecalciferol 2,000 IU daily for 6 months is generally safe and corrects HVD in most but not all individuals.
    Journal of the American Geriatrics Society 02/2011; 59(2):286-90. · 3.98 Impact Factor
  • Violet S Lagari, Silvina Levis
    [Show abstract] [Hide abstract]
    ABSTRACT: The present review summarizes the results of epidemiological studies and clinical trials assessing the skeletal effects of soy foods and soy dietary supplements. Results from epidemiological studies suggest a beneficial skeletal effect in Asian women consuming typical Asian diets, but clinical trials are conflictive regarding the effects of phytoestrogens on bone mineral density and bone turnover markers in premenopausal and postmenopausal women. Much of the controversy lies in differences in study design, reporting of results, participants' age and menopausal status, and type and dose of phytoestrogen used. Although western women will likely continue to incorporate soy foods and soy supplements into their diets with the increased availability of these products, published data are inconsistent and do not support soy's protective effect against bone loss. This conflicting evidence should be taken into account when considering using isoflavones in the prevention of bone loss and consequently fractures.
    Current opinion in endocrinology, diabetes, and obesity 12/2010; 17(6):546-53. · 3.77 Impact Factor
  • Source
    Silvina Levis, Marcio L Griebeler
    [Show abstract] [Hide abstract]
    ABSTRACT: The findings of the Women's Health Initiative resulted in a sharp decline in the use of estrogen therapy. Increasingly, menopausal women have been interested in soy foods as an alternative to estrogen therapy for the treatment of menopausal symptoms. This article provides an overview of the limited number of studies that assess the effectiveness of soy foods to alleviate vasomotor and urogenital symptoms. The evidence of the efficacy of soy foods in improving menopausal symptoms is limited due to the small number of trials reporting conflicting results.
    Journal of Nutrition 11/2010; 140(12):2318S-2321S. · 4.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Following the results of the Women's Health Initiative, many women now decline estrogen replacement at the time of menopause and seek natural remedies that would treat menopausal symptoms and prevent bone loss and other long-term consequences of estrogen deficiency, but without adverse effects on the breast, uterus, and cardiovascular system. The results of most soy studies in this population have had limitations because of poor design, small sample size, or short duration. This report describes the study rationale, design, and procedures of the Soy Phytoestrogens As Replacement Estrogen (SPARE) study, which was designed to determine the efficacy of soy isoflavones in preventing spinal bone loss and menopausal symptoms in the initial years of menopause. Women ages 45 to 60 without osteoporosis and within 5 years from menopause were randomized to receive soy isoflavones 200mg daily or placebo for 2 years. Participants have yearly measurements of spine and hip bone density, urinary phytoestrogens, and serum lipids, thyroid stimulating hormone, and estradiol. Menopausal symptoms, mood changes, depression, and quality of life are assessed annually. The SPARE study recruited 283 women, 66.1% were Hispanic white. With a large cohort, long duration, and large isoflavone dose, this trial will provide important, relevant, and currently unavailable information on the benefits of purified soy isoflavones in the prevention of bone loss and menopausal symptoms in the first 5 years of menopause. Given the high proportion of Hispanics participating in the study, the results of this trial will also be applicable to this minority group.
    Contemporary clinical trials 03/2010; 31(4):293-302. · 1.51 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chronic Fatigue Syndrome (CFS) studies from our laboratory and others described decreased natural killer cell cytotoxicity (NKCC) and elevated proportion of lymphocytes expressing the activation marker, dipeptidyl peptidase IV (DPPIV) also known as CD26. However, neither these assays nor other laboratory tests are widely accepted for the diagnosis or prognosis of CFS. This study sought to determine if NKCC or DPPIV/CD26 have diagnostic accuracy for CFS. Subjects included female and male CFS cases and healthy controls. NK cell function was measured with a bioassay, using K562 cells and (51)Cr release. Lymphocyte associated DPPIV/CD26 was assayed by qualitative and quantitative flow cytometry. Serum DPPIV/CD26 was measured by ELISA. Analysis by receiver operating characteristic (ROC) curve assessed biomarker potential. Cytotoxic function of NK cells for 176 CFS subjects was significantly lower than in the 230 controls. According to ROC analysis, NKCC was a good predictor of CFS status. There was no significant difference in NK cell counts between cases and controls. Percent CD2+ lymphocytes (T cells and NK cells) positive for DPPIV/C26 was elevated in CFS cases, but there was a decrease in the number of molecules (rMol) of DPPIV/C26 expressed on T cells and NK cells and a decrease in the soluble form of the enzyme in serum. Analyses by ROC curves indicated that all three measurements of DPPIV/CD26 demonstrated potential as biomarkers for CFS. None of the DPPIV/C26 assays were significantly correlated with NKCC. By ROC analysis, NKCC and three methods of measuring DPPIV/C26 examined in this study had potential as biomarkers for CFS. Of these, NKCC, %CD2+CD26+ lymphocytes and rMol CD26/CD2+ lymphocyte, required flow cytometry, fresh blood and access to a high complexity laboratory. Soluble DPPIV/C26 in serum is done with a standard ELISA assay, or with other soluble factors in a multiplex type of ELISA. Dipeptidyl peptidase IV on lymphocytes or in serum was not predictive of NKCC suggesting that these should be considered as non-redundant biomarkers. Abnormalities in DPPIV/CD26 and in NK cell function have particular relevance to the possible role of infection in the initiation and/or the persistence of CFS.
    PLoS ONE 01/2010; 5(5):e10817. · 3.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chronic fatigue syndrome (CFS) is a complex, multi-symptom illness with a multisystem pathogenesis involving alterations in the nervous, endocrine and immune systems.Abnormalities in stress responses have been identified as potential triggers or mediators of CFS symptoms. This study focused on the stress mediator neuropeptide Y (NPY). We hypothesized that NPY would be a useful biomarker for CFS. The CFS patients (n = 93) were from the Chronic Fatigue and Related Disorders Clinic at the University of Miami and met the 1994 case definition of Fukuda and colleagues. Healthy sedentary controls (n = 100)) were from NIH or VA funded studies. Another fatiguing, multi-symptom illness, Gulf War Illness (GWI), was also compared to CFS. We measured NPY in plasma using a radioimmunoassay (RIA). Psychometric measures, available for a subset of CFS patients included: Perceived Stress Scale, Profile of Mood States, ATQ Positive & Negative Self-Talk Scores, the COPE, the Beck Depression Inventory, Fatigue Symptom Inventory, Cognitive Capacity Screening Examination, Medical Outcomes Survey Short Form-36, and the Quality of Life Scale. Plasma NPY was elevated in CFS subjects, compared to controls (p = .000) and to GWI cases (p = .000). Receiver operating characteristics (ROC) curve analyses indicated that the predictive ability of plasma NPY to distinguish CFS patients from healthy controls and from GWI was significantly better than chance alone. In 42 patients with CFS, plasma NPY had significant correlations (<0.05) with perceived stress, depression, anger/hostility, confusion, negative thoughts, positive thoughts, general health, and cognitive status. In each case the correlation (+ or -) was in the anticipated direction. This study is the first in the CFS literature to report that plasma NPY is elevated compared to healthy controls and to a fatigued comparison group, GWI patients. The significant correlations of NPY with stress, negative mood, general health, depression and cognitive function strongly suggest that this peptide be considered as a biomarker to distinguish subsets of CFS.
    Behavioral and Brain Functions 01/2010; 6:76. · 2.79 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chronic Fatigue Syndrome (CFS) studies from our laboratory and others have described cytokine abnormalities. Other studies reported no difference between CFS and controls. However, methodologies varied widely and few studies measured more than 4 or 5 cytokines. Multiplex technology permits the determination of cytokines for a large panel of cytokines simultaneously with high sensitivity and with only 30 ul of plasma per sample. No widely accepted laboratory test or marker is available for the diagnosis or prognosis of CFS. This study screened plasma factors to identify circulating biomarkers associated with CFS. Cytokines were measured in plasma from female CFS cases and female healthy controls. Multiplex technology provided profiles of 16 plasma factors including the pro -inflammatory cytokines: tumor necrosis factor alpha (TNFalpha), lymphotoxin alpha (LTalpha), interleukin (IL) - IL-Ialpha, IL-1beta, IL-6; TH1 cytokines: interferon gamma (IFNgamma), IL-12p70, IL-2, IL-15; TH2: IL-4, IL-5; TH17 cytokines, IL-17 and IL-23; anti-inflammatory cytokines IL-10, IL-13; the inflammatory mediator and neutrophil attracting chemokine IL-8 (CXCL8). Analysis by receiver operating characteristic (ROC) curve assessed the biomarker potential of each cytokine. The following cytokines were elevated in CFS compared to controls: LTalpha, IL-1alpha, IL-1beta, IL-4, IL-5, IL-6 and IL-12. The following cytokines were decreased in CFS: IL-8, IL-13 and IL-15. The following cytokines were not different: TNFalpha, IFNgamma, IL-2, IL-10, IL-23 and IL-17. Applying (ROC) curve analyses, areas under the curves (AUC) for IL-5 (0. 84), LTalpha (0.77), IL-4 (0.77), IL-12 (0.76) indicated good biomarker potential. The AUC of IL-6 (0.73), IL-15 (0.73), IL-8 (0.69), IL-13 (0.68) IL-1alpha (0.62), IL-1beta (0.62) showed fair potential as biomarkers. Cytokine abnormalities are common in CFS. In this study, 10 of 16 cytokines examined showed good to fair promise as biomarkers. However, the cytokine changes observed are likely to more indicative of immune activation and inflammation, rather than specific for CFS. As such, they are targets for herapeutic strategies. Newer techniques allow evaluation of large panels of cytokines in a cost effective fashion.
    Journal of Translational Medicine 11/2009; 7:96. · 3.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Vitamin D, a multipurpose steroid hormone vital to health, has been increasingly implicated in the pathology of cognition and mental illness. Hypovitaminosis D is prevalent among older adults, and several studies suggest an association between hypovitaminosis D and basic and executive cognitive functions, depression, bipolar disorder, and schizophrenia. Vitamin D activates receptors on neurons in regions implicated in the regulation of behavior, stimulates neurotrophin release, and protects the brain by buffering antioxidant and anti-inflammatory defenses against vascular injury and improving metabolic and cardiovascular function. Although additional studies are needed to examine the impact of supplementation on cognition and mood disorders, given the known health benefits of vitamin D, we recommend greater supplementation in older adults.
    Current Psychiatry Reports 03/2009; 11(1):12-9. · 3.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Earlier age at menopause onset has been associated with increased all-cause, cardiovascular, and cancer mortality risks. The risk of earlier age at menopause associated with primary and secondary tobacco smoke exposure was assessed. This was a cross-sectional study using a nationally representative sample of US women. A total of 7,596 women (representing an estimated 79 million US women) from the National Health and Nutrition Examination Survey III were asked time since last menstrual period, occupation, and tobacco use (including home and workplace second-hand smoke [SHS] exposure). Blood cotinine and follicle-stimulating hormone levels were assessed. Logistic regressions for the odds of earlier age at menopause, stratified on race/ethnicity in women 25 to 50 years of age and adjusted for survey design, were controlled for age, body mass index, education, tobacco smoke exposure, and occupation. Among 5,029 US women older than 25 years with complete data, earlier age at menopause was found among all smokers and among service and manufacturing industry sector workers. Among women age 25 to 50 years, there was an increased risk of earlier age at menopause with both primary smoking and SHS exposure, particularly among black women. Primary tobacco use and SHS exposure were associated with increased odds of earlier age at menopause in a representative sample of US women. Earlier age at menopause was found for some women worker groups with greater potential occupational SHS exposure. Thus, control of SHS exposure in the workplace may decrease the risk of mortality and morbidity associated with earlier age at menopause in US women workers.
    Menopause (New York, N.Y.) 07/2008; 15(6):1103-8. · 3.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: There is a growing consensus that vitamin D recommended daily intakes for the elderly are far too low, and that all individuals should take as much vitamin D as needed to raise levels to between 32 to 40 ng/ml (80 to 100 nmol/L) (5, 108, 109). Supplementation will likely be necessary in most elderly, since according to current lifestyles, diet and sunlight alone are inadequate sources of vitamin D (17). We believe that to raise and maintain 25(OH) vitamin D levels at a minimum of 32 ng/ml (80 nmol/L), most elderly will require at least 2,000 IU of cholecalciferol per day. But many questions remain. Are other biological markers preferable to 25(OH) vitamin D to assess repletion? Do the current estimates of optimal serum levels provide health benefits for all conditions, or do optimal vitamin D levels differ depending on the target tissue? How much vitamin D, cholecalciferol, or ergocalciferol, should be given to maintain these levels? What are the molecular mechanisms by which vitamin D influences health and disease? Cross-sectional studies have suggested that low vitamin D levels not only predict nursing home admission but also are associated with increased mortality (1, 2). Further knowledge of the mechanisms of vitamin D action and prospective clinical trials designed to determine if supplementation resulting in vitamin D levels higher than those shown to reduce the risk of falls and fractures is also effective in reducing the burden of various medical conditions could help validate a cost-effective intervention that will provide greater quality of life and longevity and have a major public health impact.
    The Journal of Nutrition Health and Aging 07/2008; 12(6):366-73. · 2.39 Impact Factor

Publication Stats

881 Citations
140.21 Total Impact Points

Institutions

  • 1998–2014
    • University of Miami Miller School of Medicine
      • • Miami Veterans Affairs Medical Center
      • • Division of Hospital Medicine
      Miami, Florida, United States
  • 2009–2013
    • University of Miami
      • Miller School of Medicine
      كورال غيبلز، فلوريدا, Florida, United States
  • 2008
    • U.S. Department of Veterans Affairs
      • Geriatric Research, Education and Clinical Center (GRECC)
      Washington, D. C., DC, United States