Kim E. Innes

Oxidative stress and potential interventions to reduce oxidative stress in overweight and obesity

Purpose:  Obesity may be a state of chronic oxidative stress. Oxidative stress may be the mechanism underlying the development of co‐morbidities in obesity. This review provides a summary of the available evidence regarding systemic oxidative stress in young, older and clinical obese populations.

The Influence of Yoga-Based Programs on Risk Profiles in Adults with Type 2 Diabetes Mellitus: A Systematic Review

There is growing evidence that yoga may offer a safe and cost-effective intervention for Type 2 Diabetes mellitus (DM 2). However, systematic reviews are lacking. This article critically reviews the published literature regarding the effects of yoga-based programs on physiologic and anthropometric risk profiles and related clinical outcomes in adults with DM 2. We performed a comprehensive literature search using four computerized English and Indian scientific databases. The search was restricted to original studies (1970–2006) that evaluated the metabolic and clinical effects of yoga in adults with DM 2. Studies targeting clinical populations with cardiovascular disorders that included adults with comorbid DM were also evaluated. Data were extracted regarding study design, setting, target population, intervention, comparison group or condition, outcome assessment, data analysis and presentation, follow-up, and key results, and the quality of each study was evaluated according to specific predetermined criteria. We identified 25 eligible studies, including 15 uncontrolled trials, 6 non-randomized controlled trials and 4 randomized controlled trials (RCTs). Overall, these studies suggest beneficial changes in several risk indices, including glucose tolerance and insulin sensitivity, lipid profiles, anthropometric characteristics, blood pressure, oxidative stress, coagulation profiles, sympathetic activation and pulmonary function, as well as improvement in specific clinical outcomes. Yoga may improve risk profiles in adults with DM 2, and may have promise for the prevention and management of cardiovascular complications in this population. However, the limitations characterizing most studies preclude drawing firm conclusions. Additional high-quality RCTs are needed to confirm and further elucidate the effects of standardized yoga programs in populations with DM 2.

Preeclampsia and breast cancer risk.

Breast cancer is associated with endogenous hormone levels, but the exact relation and underlying mechanisms remain unclear. Data from several recent epidemiologic studies suggest that a woman who experiences preeclampsia in her own pregnancy, or who was herself born to a preeclamptic pregnancy, is at reduced risk for breast cancer later in life. This paper reviews the evidence for a connection between preeclampsia and breast cancer risk, and discusses the hormonal mechanisms that might explain this association. Preeclampsia is characterized by reduced levels of estrogens and insulin-like growth factor-1, and by elevated levels of progesterone, androgens, human chorionic gonadotropin, IGF-1 binding protein, corticotropin-releasing factor, cortisol, and insulin. These factors may act both individually and synergistically to decrease breast cancer risk. The occurrence of preeclampsia during a womans pregnancy may reflect an underlying hormonal profile that both predisposes her to preeclampsia and reduces her risk for breast cancer. In addition, the major hormonal alterations associated with preeclampsia during gestation may have lasting effects on subsequent breast cancer risk. Finally, the hormonal and nutritional environment of the womb, for which preeclampsia is a marker, may play an important role in programming lifelong risk for breast cancer in the female offspring.

Prevalence of restless legs syndrome in North American and Western European populations: a systematic review.

BACKGROUND Restless legs syndrome (RLS) is a potentially debilitating sleep disorder that affects a significant percentage of North American and European adults. Although standardized RLS diagnostic criteria are now established and widely accepted, reported prevalence estimates have varied widely. In this paper, we review the literature regarding RLS prevalence in North American and Western European adult populations, examine potential sources of variation, briefly discuss the impact of RLS, and offer recommendations for future research. METHODS To identify qualifying studies, we searched 6 scientific databases and scanned bibliographies of relevant review papers and all identified articles. Studies including fewer than 300 participants, that did not use any of the 4 standard diagnostic criteria, were published prior to 1995 or targeted clinical populations were excluded. RESULTS Thirty-four papers detailing results of large, population-based studies in 16 North American and Western European countries met our inclusion criteria, including 5 multi-country studies (N=69,992 participants) and 29 single country studies (N=163,188 participants); all but one were cross-sectional. Reported general prevalence rates ranged from 4% to 29% of adults, averaging 14.5±8.0% across studies. Reported prevalence averaged higher in primary care populations than in populations derived from random sampling or geographically defined cohorts (19.5±7.9% vs. 12.3±7.2%). Diagnostic and severity criteria differed considerably among studies, as did inclusion criteria, with corresponding variation in prevalence estimates. Prevalence averaged higher in women and older adults; more limited data suggest race/ethnicity, parity, health status, and other factors may also contribute to the observed variation in prevalence. RLS has profound, negative effects on health, well-being, and quality of life, yet detection rates remain low. CONCLUSIONS Collectively, these studies indicate that RLS is a common disorder of major clinical and public health significance in the Western industrialized world, affecting between 4% and 29% of adults. The wide variation in reported prevalence likely reflects differences in demographic factors, health status, and other population characteristics; study population source and sampling frame; and inconsistencies in RLS diagnostic criteria and procedures. Prospective studies and corresponding incidence data on RLS are lacking, hindering the evaluation of both causal factors and sequelae.

Restless legs syndrome and conditions associated with metabolic dysregulation, sympathoadrenal dysfunction, and cardiovascular disease risk: A systematic review

Restless legs syndrome (RLS) is a distressing sleep and sensorimotor disorder that affects a large percentage of adults in the western industrialized world and is associated with profound reductions in quality of life. However, the etiology of RLS remains incompletely understood. Enhanced understanding regarding both the antecedents and sequelae of RLS could shed new light on the pathogenesis of RLS. Evidence from an emerging body of literature suggests associations between RLS and diabetes, hypertension, obesity, and related conditions linked to sympathetic activation and metabolic dysregulation, raising the possibility that these factors may likewise play a significant role in the development and progression of RLS, and could help explain the recently documented associations between RLS and subsequent cardiovascular disease. However, the relation between RLS and these chronic conditions has received relatively little attention to date, although potential implications for the pathogenesis and treatment of RLS could be considerable. In this paper, we systematically review the recently published literature regarding the association of RLS to cardiovascular disease and related risk factors characterized by sympathoadrenal and metabolic dysregulation, discuss potential underlying mechanisms, and outline some possible directions for future research.

A woman's own birth weight and gestational age predict her later risk of developing preeclampsia, a precursor of chronic disease

Preeclampsia is a major complication of pregnancy and a predictor of future chronic disease. We investigated the hypothesis that a womans own weight and gestational age as a newborn influence her risk of developing preeclampsia later in life. This case-control study used linked computerized birth registry data from the Colorado Department of Public Health and Environment. The study subjects were women ages 12-20 who were born in Colorado after 1974, each of whom delivered a live infant in Colorado between 1990 and 1995. Cases were subjects with a report of eclampsia and/or preeclampsia on the 1990-1995 birth records (N = 345). Controls were randomly selected from subjects with uncomplicated pregnancies who were frequency matched to cases by year of delivery (N = 3,995). Records from each subjects pregnancy (1990-1995) were then linked to those from her own birth (1975-1983). Birth weight and gestational age, as recorded on the subjects birth records, were independently associated with the risk of developing preeclampsia after adjustment for age, parity, race/ethnicity, and other risk factors. The risk of preeclampsia decreased with increasing gestational age in a dose-dependent fashion; relative to mothers born post-term, adjusted odds ratios for preeclampsia ranged from 3.62 [95% confidence interval (95% CI) = 1.27-10.28] for mothers born at less than 34 weeks gestational age to 1.45 (95% CI = 0.85-2.45) for those born at term. Relative to women who were born at 8.5 lb or more, those born in the lowest weight category (under 4.5 lb) appeared at greatest risk for preeclampsia (odds ratio = 5.16; 95% CI = 1.24-21.51), although no directional trend was apparent. These findings suggest that women born small or premature may be at increased risk of developing preeclampsia as teenagers or young adults.

Mind-body therapies for menopausal symptoms: a systematic review.

OBJECTIVE To systematically review the peer-reviewed literature regarding the effects of self-administered mind-body therapies on menopausal symptoms. METHODS To identify qualifying studies, we searched 10 scientific databases and scanned bibliographies of relevant review papers and all identified articles. The methodological quality of all studies was assessed systematically using predefined criteria. RESULTS Twenty-one papers representing 18 clinical trials from 6 countries met our inclusion criteria, including 12 randomized controlled trials (N=719), 1 non-randomized controlled trial (N=58), and 5 uncontrolled trials (N=105). Interventions included yoga and/or meditation-based programs, tai chi, and other relaxation practices, including muscle relaxation and breath-based techniques, relaxation response training, and low-frequency sound-wave therapy. Eight of the nine studies of yoga, tai chi, and meditation-based programs reported improvement in overall menopausal and vasomotor symptoms; six of seven trials indicated improvement in mood and sleep with yoga-based programs, and four studies reported reduced musculoskeletal pain. Results from the remaining nine trials suggest that breath-based and other relaxation therapies also show promise for alleviating vasomotor and other menopausal symptoms, although intergroup findings were mixed. Most studies reviewed suffered methodological or other limitations, complicating interpretation of findings. CONCLUSIONS Collectively, findings of these studies suggest that yoga-based and certain other mind-body therapies may be beneficial for alleviating specific menopausal symptoms. However, the limitations characterizing most studies hinder interpretation of findings and preclude firm conclusions regarding efficacy. Additional large, methodologically sound trials are needed to determine the effects of specific mind-body therapies on menopausal symptoms, examine long-term outcomes, and investigate underlying mechanisms.

Menopause, the metabolic syndrome, and mind-body therapies.

Cardiovascular disease risk rises sharply with menopause, likely due to the coincident increase in insulin resistance and related atherogenic changes that together comprise the metabolic or insulin resistance syndrome, a cluster of metabolic and hemodynamic abnormalities strongly implicated in the pathogenesis and progression of cardiovascular disease. A growing body of research suggests that traditional mind-body practices such as yoga, tai chi, and qigong may offer safe and cost-effective strategies for reducing insulin resistance syndrome-related risk factors for cardiovascular disease in older populations, including postmenopausal women. Current evidence suggests that these practices may reduce insulin resistance and related physiological risk factors for cardiovascular disease; improve mood, well-being, and sleep; decrease sympathetic activation; and enhance cardiovagal function. However, additional rigorous studies are needed to confirm existing findings and to examine long-term effects on cardiovascular health.

Effectiveness of yoga for hypertension: systematic review and meta-analysis.

Objectives. To systematically review and meta-analyze the effectiveness of yoga for reducing blood pressure in adults with hypertension and to assess the modifying influences of type and length of yoga intervention and type of comparison group. Methods. Academic Search Premier, AltHealthWatch, BIOSIS/Biological Abstracts, CINAHL, Cochrane Library, Embase, MEDLINE, PsycINFO, PsycARTICLES, Natural Standard, and Web of Science databases were screened for controlled studies from 1966 to March 2013. Two authors independently assessed risk of bias using the Cochrane Risk of Bias Tool. Results. All 17 studies included in the review had unclear or high risk of bias. Yoga had a modest but significant effect on systolic blood pressure (SBP) (−4.17 [−6.35, −1.99], P = 0.0002) and diastolic blood pressure (DBP) (−3.62 [−4.92, −1.60], P = 0.0001). Subgroup analyses demonstrated significant reductions in blood pressure for (1) interventions incorporating 3 basic elements of yoga practice (postures, meditation, and breathing) (SBP: −8.17 mmHg [−12.45, −3.89]; DBP: −6.14 mmHg [−9.39, −2.89]) but not for more limited yoga interventions; (2) yoga compared to no treatment (SBP: −7.96 mmHg [−10.65, −5.27]) but not for exercise. Conclusion. Yoga can be preliminarily recommended as an effective intervention for reducing blood pressure. Additional rigorous controlled trials are warranted to further investigate the potential benefits of yoga.

The Effects of Meditation on Perceived Stress and Related Indices of Psychological Status and Sympathetic Activation in Persons with Alzheimer's Disease and Their Caregivers: A Pilot Study

Objective. To investigate the effects of an 8-week meditation program on perceived stress, sleep, mood, and related outcomes in adults with cognitive impairment and their caregivers. Methods. Community-dwelling adults with a diagnosis of mild cognitive impairment or early-stage Alzheimers disease, together with their live-in caregivers, were enrolled in the study. After a brief training, participants were asked to meditate for 11 minutes, twice daily for 8 weeks. Major outcomes included measures of perceived stress (Perceived Stress Scale), sleep (General Sleep Disturbance Scale), mood (Profile of Mood States), memory functioning (Memory Functioning Questionnaire), and blood pressure. Participants were assessed pre- and post-intervention. Results. Ten participants (5 of 6 dyads) completed the study. Treatment effects did not vary by participant status; analyses were thus pooled across participants. Adherence was good (meditation sessions completed/week: X = 11.4 ± 1.1). Participants demonstrated improvement in all major outcomes, including perceived stress (P < 0.001), mood (overall, P = 0.07; depression, P = 0.01), sleep (P < 0.04), retrospective memory function (P = 0.04), and blood pressure (systolic, P = 0.004; diastolic, P = 0.065). Conclusions. Findings of this exploratory trial suggest that an 8-week meditation program may offer an acceptable and effective intervention for reducing perceived stress and improving certain domains of sleep, mood, and memory in adults with cognitive impairment and their caregivers.