1000 resultados para systematic
Resumo:
Background
Exercise is widely recommended to reduce osteoporosis, falls and related fragility fractures, but its effect on whole bone strength has remained inconclusive. The primary purpose of this systematic review and meta-analysis was to evaluate the effects of long-term supervised exercise (≥6 months) on estimates of lower-extremity bone strength from childhood to older age.
Methods
We searched four databases (PubMed, Sport Discus, Physical Education Index, and Embase) up to October 2009 and included 10 randomised controlled trials (RCTs) that assessed the effects of exercise training on whole bone strength. We analysed the results by age groups (childhood, adolescence, and young and older adulthood) and compared the changes to habitually active or sedentary controls. To calculate standardized mean differences (SMD; effect size), we used the follow-up values of bone strength measures adjusted for baseline bone values. An inverse variance-weighted random-effects model was used to pool the results across studies.
Results
Our quality analysis revealed that exercise regimens were heterogeneous; some trials were short in duration and small in sample size, and the weekly training doses varied considerably between trials. We found a small and significant exercise effect among pre- and early pubertal boys [SMD, effect size, 0.17 (95% CI, 0.02-0.32)], but not among pubertal girls [-0.01 (-0.18 to 0.17)], adolescent boys [0.10 (-0.75 to 0.95)], adolescent girls [0.21 (-0.53 to 0.97)], premenopausal women [0.00 (-0.43 to 0.44)] or postmenopausal women [0.00 (-0.15 to 0.15)]. Evidence based on per-protocol analyses of individual trials in children and adolescents indicated that programmes incorporating regular weight-bearing exercise can result in 1% to8% improvements in bone strength at the loaded skeletal sites. In premenopausal women with high exercise compliance, improvements ranging from 0.5% to 2.5% have been reported.
Conclusions
The findings from our meta-analysis of RCTs indicate that exercise can significantly enhance bone strength at loaded sites in children but not in adults. Since few RCTs were conducted to investigate exercise effects on bone strength, there is still a need for further well-designed, long-term RCTs with adequate sample sizes to quantify the effects of exercise on whole bone strength and its structural determinants throughout life.
Resumo:
Objective : To assess the association between 25-hydroxyvitamin D (25[OH]D) status and obesity, cardiovascular diseases (CVDs), the metabolic syndrome, and type 2 diabetes mellitus (T2DM) in ethnic minorities.
Methods : Databases searched were CINHAL with full text, Global Health, MEDLINE with full text, and PsycINFO from 1980 through 2010 (February). Studies were included if they 1) targeted immigrants from low- to high-income countries or ethnic minorities, 2) focused primarily on 25(OH)D and its relation to obesity, T2DM, and/or CVDs, and 3) were published in peer-reviewed journals. The influences of key confounders such as age, gender, and ethnicity on any observed relations were also assessed. Due to the heterogeneity of study characteristics, only a narrative synthesis was undertaken.
Results : Ethnic minorities had significantly higher rates of vitamin D insufficiency (25[OH]D <50 nmol/L; children 43.6–48.7% versus 10%; adults 30.3–53% versus 13.7–26%) than their white counterparts. None of the studies reported a prevalence of obesity stratified by ethnicity. There was evidence supporting links between vitamin D deficiency and obesity-related chronic diseases, with 14 of 14 studies reporting a statistically significant result with a measurement of obesity, four of five for T2DM, four of five for CVDs, and one of one for the metabolic syndrome. However, the strength of the association varied across ethnic groups depending on the index used to measure adiposity, T2DM, and CVDs. Because most of the included studies were cross-sectional and there were variations in outcome measurements, it was not possible to determine the relative contributions of obesity or vitamin D insufficiency to CVD risk and risk of T2DM or which is the initial driver It is possible both have a role to play.
Conclusion : Further research specific to migrant populations using randomized controlled trials are required to establish whether causal links between 25(OH)D and obesity-related chronic disease exist, and whether vitamin D supplementation could be valuable in the prevention or treatment of obesity-related diseases.
Resumo:
Background : There is considerable geographic variation in stroke mortality around the United Kingdom (UK). Whether this is due to geographical differences in incidence or case-fatality is unclear. We conducted a systematic review of high-quality studies documenting the incidence of any stroke and stroke subtypes, between 1985 and 2008 in the UK. We aimed to study geographic and temporal trends in relation to equivalent mortality trends.
Methods : MEDLINE and EMBASE were searched, reference lists inspected and authors of included papers were contacted. All rates were standardised to the European Standard Population for those over 45, and between 45 and 74 years. Stroke mortality rates for the included areas were then calculated to produce rate ratios of stroke mortality to incidence for each location.
Results : Five papers were included in this review. Geographic variation was narrow but incidence appeared to largely mirror mortality rates for all stroke. For men over 45, incidence (and confidence intervals) per 100,000 ranged from 124 (109-141) in South London, to 185 (164-208) in Scotland. For men, premature (45-74 years) stroke incidence per 100,000 ranged from 79 (67-94) in the North West, to 112 (95-132) in Scotland. Stroke subtype data was more geographically restricted, but did suggest there is no sizeable variation in incidence by subtype around the country. Only one paper, based in South London, had data on temporal trends. This showed that there has been a decline in stroke incidence since the mid 1990 s. This could not be compared to any other locations in this review.
Conclusions : Geographic variations in stroke incidence appear to mirror variations in mortality rates. This suggests policies to reduce inequalities in stroke mortality should be directed at risk factor profiles rather than treatment after a first incident event. More high quality stroke incidence data from around the UK are needed before this can be confirmed.
Resumo:
Aims For selected individuals with complex Type 1 diabetes, pancreatic islet transplantation (IT) offers the potential of excellent glycaemic controlwithout significant hypoglycaemia, balanced by the need for ongoing systemic immunosuppression. Increasingly, patient-reported outcomes (PROs) are considered alongside biomedical outcomes as a measure of transplant success. PROs in IT have not previously been compared directlywith the closest alternate treatment option, pancreas transplant alone (PTA) or pancreas after kidney (PAK).
Methods We used a Population, Intervention, Comparisons, Outcomes (PICO) strategy to search Scopus and screened 314 references for inclusion.
Results Twelve studies [including PRO assessment of PAK, PTA, islet-after kidney (IAK) and islet transplant alone (ITA); n = 7–205] used a total of nine specified and two unspecified PRO measures. Results were mixed but identified some benefits which remained apparent up to 36 months post-transplant, including improvements in fear of hypoglycaemia, as well as some aspects of diabetes-specific quality of life (QoL) and general health status. Negative outcomes included short-term pain associated with the procedure, immunosuppressant side effects and depressed mood associated with loss of graft function.
Conclusions The mixed resultsmay be attributable to limited sample sizes. Also, some PROmeasures may lack sensitivity to detect actual changes, as they exclude issues and domains of life likely to be important forQoL post-transplantation and when patients may no longer perceive themselves to have diabetes. Thus, the full impact of islet ⁄ pancreas transplantation (alone or after kidney) on QoL is unknown. Furthermore, no studies have assessed patient satisfaction, which may highlight further advantages and disadvantages of transplantation.
Resumo:
Restless legs syndrome (RLS) is a neurological movement disorder characterized by sensory symptoms and motor disturbances. While the underlying cause remains unknown, it is suggested that 20–25% of people with RLS are affected seriously enough to require pharmacological treatment. Dopamine agonists (DAs) are the most common treatment and act by increasing the low levels of dopamine to which RLS is often attributed. A growing literature highlights the debilitating and distressing nature of this condition from the patient's perspective. While sleep problems are most commonly reported, the impact of RLS on quality of life (QOL) is wide ranging, affecting relationships with partners, sex life, family life, social life, leisure activities, friendships, everyday activities, concentration, travel, career/work, sleep, and health.
We conducted a systematic review of clinical trials in which DAs have been evaluated in terms of RLS-specific QOL, i.e. their impact on the QOL of people with RLS, and critically reviewed the development history and measurement properties of RLS-specific QOL instruments.
A systematic search using terms synonymous with RLS, DAs and QOL was conducted using Scopus software, which includes MEDLINE, PsycINFO, EMBASE, and CINAHL. Our search covered publications from 2000 (prior to which RLS-specific QOL measures did not exist) to August 2009. Trials were included in our review if they evaluated DAs for the treatment of adults with RLS and reported evaluation using an RLS-specific QOL measure. We also ran citation searches to identify papers reporting the development history and measurement properties of the identified RLS-specific QOL instruments.
Three measures of RLS-specific QOL have been developed in recent years and are reviewed here: the Restless Legs Syndrome Quality of Life (RLSQOL) questionnaire, the Restless Legs Syndrome Quality of Life Instrument (RLS-QLI), and the Quality of Life Restless Legs Syndrome (QOL-RLS) measure. Critical review indicates that each has limitations (particularly in terms of published developmental history and content validity). Eleven trials of DAs were identified that included assessment of RLS-specific QOL (nine using the RLSQOL and two using the QOL-RLS). In all studies, significant improvements in RLS-specific QOL were observed, although these were mostly short term (12 weeks) and large placebo effects were also noted.
In people with RLS, the use of DAs has been shown to improve RLS-specific QOL. Longer-term, large-scale studies may be needed to confirm these findings and demonstrate statistically significant improvements in RLS-specific QOL at lower doses. Further development of the RLS-specific QOL measures is needed to ensure that the full impact of RLS (and the full benefit of new treatments) on aspects of life identified as important to individuals is captured in future studies.
Resumo:
Hypoglycemia is the commonest and most serious side-effect of insulin treatment for Type 1 diabetes (T1DM). The prevalence of hypoglycemia is lower in insulin-treated Type 2 diabetes (T2DM) than in T1DM but the prevalence increases with duration of insulin therapy and increasingly resembles T1DM. As hypoglycemia has not been widely recognised to affect people with T2DM, its impact on quality of life (QoL) has received little attention.
A systematic literature review was performed to identify empirical papers published in English since 1966 reporting the effect of hypoglycemia on any patient-reported outcomes (PROs), including QoL, in T2DM. Despite our specific interest in QoL, the inclusion criteria were defined broadly to encompass a range of self-assessed psychosocial outcomes, including generic and diabetes-specific QoL, emotional well-being and health utilities. Studies were excluded in which the impact of hypoglycemia was confounded by treatment effects. Our search included: MEDLINE, PsycINFO, CINAHL. Abstracts were screened independently by two investigators.
Of 2,469 abstracts, Thirty-one met the inclusion criteria and were subjected to data extraction and analysis. These comprised four controlled trials and twenty-seven others (including cross-sectional and health utility studies). The results indicate associations between the experience of hypoglycemia and a range of adverse PROs, including impaired QoL and well-being, higher levels of anxiety, depression and anger and loss of health utility. Fear of hypoglycemia was also associated with compensatory lifestyle limitations and changes.
Publications suggest that QoL and other psychosocial outcomes are impaired by the experience and/or fear of hypoglycemia in T2DM, however, very few studies have directly investigated this phenomenon to date. Interpretation of the evidence is hampered by inconsistent or inadequate definitions and measurement of both hypoglycemia and QoL outcomes, by confounding of the impact of hypoglycemia and by treatment factors. Targeted research using appropriate study design is needed to quantify and qualify the true impact of hypoglycemia on QoL in people with T2DM.
Resumo:
The aim of this review was to evaluate the reliability and validity of methods used to assess the multiple components of sedentary behaviour (i.e. screen time, sitting, not moving and existing at low energy expenditure) in children and adolescents. Twenty-six studies met our inclusion criteria and were reviewed. Thirteen studies reported the reliability of self- and proxy-report measures of sedentary behaviour and seven of these were found to have acceptable test–retest reliability. Evidence for the criterion validity of self- and proxy-report measures was examined in three studies with mixed results. Seven studies examined the reliability and/or validity of direct observation and the findings were generally positive. Five studies demonstrated the utility of accelerometers to accurately classify sedentary behaviour. Self-report measures provide reliable estimates of screen time, yet their validity remains largely untested. While accelerometers can accurately classify participants’ behaviour as sedentary, they do not provide information about type of sedentary behaviour or context. Studies utilizing measures of sedentary behaviour need to more adequately report on the validity and reliability of the measures used.We recommend the use of objective measures of sedentary behaviour such as accelerometers, in conjunction with subjective measures (e.g. self-report), to assess type and context of behaviour.
