Ngianga-Bakwin Kandala

Gender-specific associations of short sleep duration with prevalent and incident hypertension: the Whitehall II Study.

Sleep deprivation (≤5 hour per night) was associated with a higher risk of hypertension in middle-aged American adults but not among older individuals. However, the outcome was based on self-reported diagnosis of incident hypertension, and no gender-specific analyses were included. We examined cross-sectional and prospective associations of sleep duration with prevalent and incident hypertension in a cohort of 10 308 British civil servants aged 35 to 55 years at baseline (phase 1: 1985–1988). Data were gathered from phase 5 (1997–1999) and phase 7 (2003–2004). Sleep duration and other covariates were assessed at phase 5. At both examinations, hypertension was defined as blood pressure ≥140/90 mm Hg or regular use of antihypertensive medications. In cross-sectional analyses at phase 5 (n=5766), short duration of sleep (≤5 hour per night) was associated with higher risk of hypertension compared with the group sleeping 7 hours, among women (odds ratio: 2.01; 95% CI: 1.13 to 3.58), independent of confounders, with an inverse linear trend across decreasing hours of sleep (P=0.003). No association was detected in men. In prospective analyses (mean follow-up: 5 years), the cumulative incidence of hypertension was 20.0% (n=740) among 3691 normotensive individuals at phase 5. In women, short duration of sleep was associated with a higher risk of hypertension in a reduced model (age and employment) (6 hours per night: odds ratio: 1.56 [95% CI: 1.07 to 2.27]; ≤5 hour per night: odds ratio: 1.94 [95% CI: 1.08 to 3.50] versus 7 hours). The associations were attenuated after accounting for cardiovascular risk factors and psychiatric comorbidities (odds ratio: 1.42 [95% CI: 0.94 to 2.16]; odds ratio: 1.31 [95% CI: 0.65 to 2.63], respectively). Sleep deprivation may produce detrimental cardiovascular effects among women.

Levels of vitamin D and cardiometabolic disorders: Systematic review and meta-analysis

Cardiometabolic disorders and vitamin D deficiency are becoming increasingly more prevalent across multiple populations. Different studies have suggested a potential association between abnormal vitamin D levels and multiple pathological conditions including cardiovascular diseases and diabetes. We aimed to evaluate the association between vitamin D levels, using 25-hydroxy vitamin D (25OHD) as an indicator of vitamin D status, and the presence of cardiometabolic disorders including cardiovascular disease, diabetes and metabolic syndrome. We performed a systematic review of the current literature on vitamin D and cardiometabolic disorders using the PubMed and Web of Knowledge databases in September 2009. Studies in adults looking at the effect of vitamin D levels on outcomes relating to cardiometabolic disorders were selected. We performed a meta-analysis to assess the risk of developing cardiometabolic disorders comparing the highest and lowest groups of serum 25OHD. From 6130 references we identified 28 studies that met our inclusion criteria, including 99,745 participants. There was moderate variation between the studies in their grouping of 25OHD levels, design and analytical approach. We found that the highest levels of serum 25OHD were associated with a 43% reduction in cardiometabolic disorders [OR 0.57, 95% (CI 0.48-0.68)]. Similar levels were observed, irrespective of the individual cardiometabolic outcome evaluated or study design. High levels of vitamin D among middle-age and elderly populations are associated with a substantial decrease in cardiovascular disease, type 2 diabetes and metabolic syndrome. If the relationship proves to be causal, interventions targeting vitamin D deficiency in adult populations could potentially slow the current epidemics of cardiometabolic disorders.

Correlates of short and long sleep duration: a cross-cultural comparison between the United Kingdom and the United States: the Whitehall II Study and the Western New York Health Study.

The authors examined sociodemographic, lifestyle, and comorbidity factors that could confound or mediate U-shaped associations between sleep duration and health in 6,472 United Kingdom adults from the Whitehall II Study (1997-1999) and 3,027 US adults from the Western New York Health Study (1996-2001). Cross-sectional associations between short (<6 hours) and long (>8 hours) durations of sleep across several correlates were calculated as multivariable odds ratios. For short sleep duration, there were significant, consistent associations in both samples for unmarried status (United Kingdom: adjusted odds ratio (AOR) = 1.49, 95% confidence interval (CI): 1.15, 1.94; United States: AOR = 1.49, 95% CI: 1.10, 2.02), body mass index (AORs were 1.04 (95% CI: 1.01, 1.07) and 1.02 (95% CI: 1.00, 1.05)), and Short Form-36 physical (AORs were 0.96 (95% CI: 0.95, 0.98) and 0.97 (95% CI: 0.96, 0.98)) and mental (AORs were 0.95 (95% CI: 0.94, 0.96) and 0.98 (95% CI: 0.96, 0.99)) scores. For long sleep duration, there were fewer significant associations: age among men (AORs were 1.08 (95% CI: 1.01, 1.14) and 1.05 (95% CI: 1.02, 1.08)), low physical activity (AORs were 1.75 (95% CI: 0.97, 3.14) and 1.60 (95% CI: 1.09, 2.34)), and Short Form-36 physical score (AORs were 0.96 (95% CI: 0.93, 0.99) and 0.97 (95% CI: 0.95, 0.99)). Being unmarried, being overweight, and having poor general health are associated with short sleep and may contribute to observed disease associations. Long sleep may represent an epiphenomenon of comorbidity.

Sleep Problems: An Emerging Global Epidemic? Findings From the INDEPTH WHO-SAGE Study Among More Than 40,000 Older Adults From 8 Countries Across Africa and Asia

OBJECTIVE To estimate the prevalence of sleep problems and the effect of potential correlates in low-income settings from Africa and Asia, where the evidence is lacking. DESIGN Cross-sectional. SETTING Community-wide samples from 8 countries across Africa and Asia participating in the INDEPTH WHO-SAGE multicenter collaboration during 2006-2007. The participating sites included rural populations in Ghana, Tanzania, South Africa, India, Bangladesh, Vietnam, and Indonesia, and an urban area in Kenya. PARTICIPANTS There were 24,434 women and 19,501 men age 50 yr and older. INTERVENTIONS N/A. MEASUREMENTS AND RESULTS Two measures of sleep quality, over the past 30 days, were assessed alongside a number of sociodemographic variables, measures of quality of life, and comorbidities. Overall, 16.6% of participants reported severe/extreme nocturnal sleep problems, with a striking variation across the 8 populations, ranging from 3.9% (Purworejo, Indonesia and Nairobi, Kenya) to more than 40.0% (Matlab, Bangladesh). There was a consistent pattern of higher prevalence of sleep problems in women and older age groups. In bivariate analyses, lower education, not living in partnership, and poorer self-rated quality of life were consistently associated with higher prevalence of sleep problems (P < 0.001). In multivariate logistic regression analyses, limited physical functionality or greater disability and feelings of depression and anxiety were consistently strong, independent correlates of sleep problems, in both women and men, across the 8 sites (P < 0.001). CONCLUSIONS A large number of older adults in low-income settings are currently experiencing sleep problems, which emphasizes the global dimension of this emerging public health issue. This study corroborates the multifaceted nature of sleep problems, which are strongly linked to poorer general well-being and quality of life, and psychiatric comorbidities.

A population-based study of reduced sleep duration and hypertension: the strongest association may be in premenopausal women.

Objectives Recent evidence indicates that reduced sleep duration may be associated with an increased risk of hypertension with possibly stronger effects among women than men. We therefore examined cross-sectional sex-specific associations of sleep duration with hypertension in a large population-based sample from the Western New York Health Study (1996<2001). Methods Participants were 3027 white men (43.5%) and women (56.5%) without prevalent cardiovascular disease (median age 56 years). Hypertension was defined as blood pressure at least 140 or at least 90&mmHg or regular use of antihypertensive medication. Multivariate logistic regression analyses were performed to estimate odds ratios (ORs) of hypertension comparing less than 6&h of sleep per night versus the reference category (&6&h) while accounting for a number of potential confounders. Results In multivariate analyses, less than 6&h of sleep was associated with a significant increased risk of hypertension compared to sleeping at least 6&h per night, only among women [OR&=&1.66 (1.09 to 2.53)]. No significant association was found among men [OR&=&0.93 (0.62 to 1.41)]. In subgroup analyses by menopausal status, the effect was stronger among premenopausal women [OR&=&3.25 (1.37 to 7.76)] than among postmenopausal women [OR&=&1.49 (0.92 to 2.41)]. Conclusion Reduced sleep duration, by increasing the risk of hypertension, may produce detrimental cardiovascular effects among women. The association is independent of socioeconomic status, traditional cardiovascular risk factors, and psychiatric comorbidities, and is stronger among premenopausal women. Prospective and mechanistic evidence is necessary to support causality.

Faecal calprotectin testing for differentiating amongst inflammatory and non-inflammatory bowel diseases: systematic review and economic evaluation.

BACKGROUND Irritable bowel syndrome (IBS) is common, and causes pain, bloating and diarrhoea and/or constipation. It is a troublesome condition that reduces the quality of life but causes no permanent damage. Inflammatory bowel disease (IBD) comprises mainly ulcerative colitis (UC) and Crohns disease (CD). Both cause serious complications and may lead to sections of the bowel having to be removed, although this is more common with CD. The presenting symptoms of IBS and IBD can be similar. Distinguishing them on clinical signs and symptoms can be difficult. Until recently, colonoscopy was often required to rule out IBD. In younger people, > 60% of colonoscopies showed no abnormality. Faecal calprotectin (FC) is a protein released by the white blood cells, neutrophils, found in inflamed areas of the bowel in IBD. Determining the level of FC in stool samples may help distinguish IBS from IBD. OBJECTIVE To review the value of FC for distinguishing between IBD and non-IBD. DATA SOURCES Sources included MEDLINE, EMBASE, The Cochrane Library, Web of Science, websites of journals and the European Crohns and Colitis Organisation (conference abstracts 2012 and 2013), and contact with experts. REVIEW METHODS Systematic review and economic modelling. Review Manager (RevMan) version 5.2 (The Cochrane Collaboration, The Nordic Cochrane Centre, Copenhagen, Denmark) was used for most analysis, with statistical analyses done in Stata version 12 (StataCorp LP, College Station, TX, USA). Forest plots and receiver operating characteristic curves were produced. Quality Assessment of Diagnostic Accuracy Studies was used for quality assessment. Economic modelling was done in Microsoft Excel 2010 (Microsoft Corporation, Redmond, WA, USA). LIMITATIONS Studies were often small, most used only one calprotectin cut-off level, and nearly all came from secondary care populations. RESULTS Twenty-eight studies provided data for 2 × 2 tables and were included in meta-analyses, with seven in the most important comparison in adults (IBS vs. IBD) and eight in the key comparison in paediatrics (IBD vs. non-IBD). Most studies used laboratory enzyme-linked immunosorbent assay (ELISA) tests. For distinguishing between IBD and IBS in adults, these gave pooled sensitivity of 93% and specificity of 94% at FC cut-off level of 50 µg/g. Sensitivities at that cut-off ranged from 83% to 100%, and specificities from 60% to 100%. For distinguishing between IBD and non-IBD in paediatric populations with ELISA tests, sensitivities ranged from 95% to 100% at cut-off of 50 µg/g and specificities of 44-93%. Few studies used point-of-care testing but that seemed as reliable as ELISA, though perhaps less specific. The evidence did not provide any grounds for preferring one test over others on clinical effectiveness grounds. FC testing in primary care could reduce the need for referral and colonoscopies. Any quality-adjusted life-year gains are likely to be small because of the low prevalence of IBD and the high sensitivities of all of the tests, resulting in few false negatives with IBD. However, considerable savings could accrue. Areas of uncertainty include the optimum management of people with borderline results (50-150 µg/g), most of whom do not have IBD. Repeat testing may be appropriate before referral. CONCLUSIONS Faecal calprotectin can be a highly sensitive way of detecting IBD, although there are inevitably trade-offs between sensitivity and specificity, with some false positives (IBS with positive calprotectin) if a low calprotectin cut-off is used. In most cases, a negative calprotectin rules out IBD, thereby sparing most people with IBS from having to have invasive investigations, such as colonoscopy. STUDY REGISTRATION PROSPERO CRD 42012003287. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Aspirin for prophylactic use in the primary prevention of cardiovascular disease and cancer: a systematic review and overview of reviews

BACKGROUND Prophylactic aspirin has been considered to be beneficial in reducing the risks of heart disease and cancer. However, potential benefits must be balanced against the possible harm from side effects, such as bleeding and gastrointestinal (GI) symptoms. It is particularly important to know the risk of side effects when aspirin is used as primary prevention--that is when used by people as yet free of, but at risk of developing, cardiovascular disease (CVD) or cancer. In this report we aim to identify and re-analyse randomised controlled trials (RCTs), systematic reviews and meta-analyses to summarise the current scientific evidence with a focus on possible harms of prophylactic aspirin in primary prevention of CVD and cancer. OBJECTIVES To identify RCTs, systematic reviews and meta-analyses of RCTs of the prophylactic use of aspirin in primary prevention of CVD or cancer. To undertake a quality assessment of identified systematic reviews and meta-analyses using meta-analysis to investigate study-level effects on estimates of benefits and risks of adverse events; cumulative meta-analysis; exploratory multivariable meta-regression; and to quantify relative and absolute risks and benefits. METHODS We identified RCTs, meta-analyses and systematic reviews, and searched electronic bibliographic databases (from 2008 September 2012) including MEDLINE, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, NHS Centre for Reviews and Dissemination, and Science Citation Index. We limited searches to publications since 2008, based on timing of the most recent comprehensive systematic reviews. RESULTS In total, 2572 potentially relevant papers were identified and 27 met the inclusion criteria. Benefits of aspirin ranged from 6% reduction in relative risk (RR) for all-cause mortality [RR 0.94, 95% confidence interval (CI) 0.88 to 1.00] and 10% reduction in major cardiovascular events (MCEs) (RR 0.90, 95% CI 0.85 to 0.96) to a reduction in total coronary heart disease (CHD) of 15% (RR 0.85, 95% CI 0.69 to 1.06). Reported pooled odds ratios (ORs) for total cancer mortality ranged between 0.76 (95% CI 0.66 to 0.88) and 0.93 (95% CI 0.84 to 1.03). Inclusion of the Womens Health Study changed the estimated OR to 0.82 (95% CI 0.69 to 0.97). Aspirin reduced reported colorectal cancer (CRC) incidence (OR 0.66, 95% CI 0.90 to 1.02). However, including studies in which aspirin was given every other day raised the OR to 0.91 (95% CI 0.74 to 1.11). Reported cancer benefits appeared approximately 5 years from start of treatment. Calculation of absolute effects per 100,000 patient-years of follow-up showed reductions ranging from 33 to 46 deaths (all-cause mortality), 60-84 MCEs and 47-64 incidents of CHD and a possible avoidance of 34 deaths from CRC. Reported increased RRs of adverse events from aspirin use were 37% for GI bleeding (RR 1.37, 95% CI 1.15 to 1.62), between 54% (RR 1.54, 95% CI 1.30 to 1.82) and 62% (RR 1.62, 95% CI 1.31 to 2.00) for major bleeds, and between 32% (RR 1.32, 95% CI 1.00 to 1.74) and 38% (RR 1.38, 95% CI 1.01 to 1.82) for haemorrhagic stroke. Pooled estimates of increased RR for bleeding remained stable across trials conducted over several decades. Estimates of absolute rates of harm from aspirin use, per 100,000 patient-years of follow-up, were 99-178 for non-trivial bleeds, 46-49 for major bleeds, 68-117 for GI bleeds and 8-10 for haemorrhagic stroke. Meta-analyses aimed at judging risk of bleed according to sex and in individuals with diabetes were insufficiently powered for firm conclusions to be drawn. LIMITATIONS Searches were date limited to 2008 because of the intense interest that this subject has generated and the cataloguing of all primary research in so many previous systematic reviews. A further limitation was our potential over-reliance on study-level systematic reviews in which the person-years of follow-up were not accurately ascertainable. However, estimates of number of events averted or incurred through aspirin use calculated from data in study-level meta-analyses did not differ substantially from estimates based on individual patient data-level meta-analyses, for which person-years of follow-up were more accurate (although based on less-than-complete assemblies of currently available primary studies). CONCLUSIONS We have found that there is a fine balance between benefits and risks from regular aspirin use in primary prevention of CVD. Effects on cancer prevention have a long lead time and are at present reliant on post hoc analyses. All absolute effects are relatively small compared with the burden of these diseases. Several potentially relevant ongoing trials will be completed between 2013 and 2019, which may clarify the extent of benefit of aspirin in reducing cancer incidence and mortality. Future research considerations include expanding the use of IPD meta-analysis of RCTs by pooling data from available studies and investigating the impact of different dose regimens on cardiovascular and cancer outcomes. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Malnutrition among children under the age of five in the Democratic Republic of Congo (DRC): does geographic location matter?

BackgroundAlthough there are inequalities in child health and survival in the Democratic Republic of Congo (DRC), the influence of distal determinants such as geographic location on childrens nutritional status is still unclear. We investigate the impact of geographic location on child nutritional status by mapping the residual net effect of malnutrition while accounting for important risk factors.MethodsWe examine spatial variation in under-five malnutrition with flexible geo-additive semi-parametric mixed model while simultaneously controlling for spatial dependence and possibly nonlinear effects of covariates within a simultaneous, coherent regression framework based on Markov Chain Monte Carlo techniques. Individual data records were constructed for children. Each record represents a child and consists of nutritional status information and a list of covariates. For the 8,992 children born within the last five years before the survey, 3,663 children have information on anthropometric measures.Our novel empirical approach is able to flexibly determine to what extent the substantial spatial pattern of malnutrition is driven by detectable factors such as socioeconomic factors and can be attributable to unmeasured factors such as conflicts, political, environmental and cultural factors.ResultsAlthough childhood malnutrition was more pronounced in all provinces of the DRC, after accounting for the locations effects, geographic differences were significant: malnutrition was significantly higher in rural areas compared to urban centres and this difference persisted after multiple adjustments. The findings suggest that models of nutritional intervention must be carefully specified with regard to residential location.ConclusionChildhood malnutrition is spatially structured and rates remain very high in the provinces that rely on the mining industry and comparable to the level seen in Eastern provinces under conflicts. Even in provinces such as Bas-Congo that produce foods, childhood malnutrition is higher probably because of the economic decision to sell more than the population consumes. Improving maternal and child nutritional status is a prerequisite for achieving MDG 4, to reduce child mortality rate in the DRC.

Improved Glycemic Control and Vascular Function in Overweight and Obese Subjects by Glyoxalase 1 Inducer Formulation

Risk of insulin resistance, impaired glycemic control, and cardiovascular disease is excessive in overweight and obese populations. We hypothesized that increasing expression of glyoxalase 1 (Glo1)—an enzyme that catalyzes the metabolism of reactive metabolite and glycating agent methylglyoxal—may improve metabolic and vascular health. Dietary bioactive compounds were screened for Glo1 inducer activity in a functional reporter assay, hits were confirmed in cell culture, and an optimized Glo1 inducer formulation was evaluated in a randomized, placebo-controlled crossover clinical trial in 29 overweight and obese subjects. We found trans-resveratrol (tRES) and hesperetin (HESP), at concentrations achieved clinically, synergized to increase Glo1 expression. In highly overweight subjects (BMI >27.5 kg/m2), tRES-HESP coformulation increased expression and activity of Glo1 (27%, P < 0.05) and decreased plasma methylglyoxal (−37%, P < 0.05) and total body methylglyoxal-protein glycation (−14%, P < 0.01). It decreased fasting and postprandial plasma glucose (−5%, P < 0.01, and −8%, P < 0.03, respectively), increased oral glucose insulin sensitivity index (42 mL ⋅ min−1 ⋅ m−2, P < 0.02), and improved arterial dilatation Δbrachial artery flow-mediated dilatation/Δdilation response to glyceryl nitrate (95% CI 0.13–2.11). In all subjects, it decreased vascular inflammation marker soluble intercellular adhesion molecule-1 (−10%, P < 0.01). In previous clinical evaluations, tRES and HESP individually were ineffective. tRES-HESP coformulation could be a suitable treatment for improved metabolic and vascular health in overweight and obese populations.

A systematic review of evidence on malignant spinal metastases: natural history and technologies for identifying patients at high risk of vertebral fracture and spinal cord compression

BACKGROUND Spinal metastases can lead to significant morbidity and reduction in quality of life due to spinal cord compression (SCC). Between 5% and 20% of patients with spinal metastases develop metastatic spinal cord compression during the course of their disease. An early study estimated average survival for patients with SCC to be between 3 and 7 months, with a 36% probability of survival to 12 months. An understanding of the natural history and early diagnosis of spinal metastases and prediction of collapse of the metastatic vertebrae are important. OBJECTIVES To undertake a systematic review to examine the natural history of metastatic spinal lesions and to identify patients at high risk of vertebral fracture and SCC. DATA SOURCES The search strategy covered the concepts of metastasis, the spine and adults. Searches were undertaken from inception to June 2011 in 13 electronic databases [MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; EMBASE; Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials (CENTRAL); Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database (NHS EED), HTA databases (NHS Centre for Reviews and Dissemination); Science Citation Index and Conference Proceedings (Web of Science); UK Clinical Research Network (UKCRN) Portfolio Database; Current Controlled Trials; ClinicalTrials.gov]. REVIEW METHODS Titles and abstracts of retrieved studies were assessed by two reviewers independently. Disagreement was resolved by consensus agreement. Full data were extracted independently by one reviewer. All included studies were reviewed by a second researcher with disagreements resolved by discussion. A quality assessment instrument was used to assess bias in six domains: study population, attrition, prognostic factor measurement, outcome measurement, confounding measurement and account, and analysis. Data were tabulated and discussed in a narrative review. Each tumour type was looked at separately. RESULTS In all, 2425 potentially relevant articles were identified, of which 31 met the inclusion criteria. No study examined natural history alone. Seventeen studies reported retrospective data, 10 were prospective studies, and three were other study designs. There was one systematic review. There were no randomised controlled trials (RCTs). Approximately 5782 participants were included. Sample sizes ranged from 41 to 859. The age of participants ranged between 7 and 92 years. Types of cancers reported on were lung alone (n= 3), prostate alone (n= 6), breast alone (n= 7), mixed cancers (n= 13) and unclear (n= 1). A total of 93 prognostic factors were identified as potentially significant in predicting risk of SCC or collapse. Overall findings indicated that the more spinal metastases present and the longer a patient was at risk, the greater the reported likelihood of development of SCC and collapse. There was an increased risk of developing SCC if a cancer had already spread to the bones. In the prostate cancer studies, tumour grade, metastatic load and time on hormone therapy were associated with increased risk of SCC. In one study, risk of SCC before death was 24%, and 2.37 times greater with a Gleason score ≥ 7 than with a score of < 7 (p= 0.003). Other research found that patients with six or more bone lesions were at greater risk of SCC than those with fewer than six lesions [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.012 to 8.35, p= 0.047]. For breast cancer patients who received a computerised tomography (CT) scan for suspected SCC, multiple logistic regression in one study identified four independent variables predictive of a positive test: bone metastases ≥ 2 years (OR 3.0 95% CI 1.2 to 7.6; p= 0.02); metastatic disease at initial diagnosis (OR 3.4, 95% CI 1.0 to 11.4; p= 0.05); objective weakness (OR 3.8, 95% CI 1.5 to 9.5; p= 0.005); and vertebral compression fracture on spine radiograph (OR 2.6, 95% CI 1.0 to 6.5; p= 0.05). A further study on mixed cancers, among patients who received surgery for SCC, reported that vertebral body compression fractures were associated with presurgery chemotherapy (OR 2.283, 95% CI 1.064 to 4.898; p= 0.03), cancer type [primary breast cancer (OR 4.179, 95% CI 1.457 to 11.983; p= 0.008)], thoracic involvement (OR 3.505, 95% CI 1.343 to 9.143; p= 0.01) and anterior cord compression (OR 3.213, 95% CI 1.416 to 7.293; p= 0.005). LIMITATIONS Many of the included studies provided limited information about patient populations and selection criteria and they varied in methodological quality, rigour and transparency. Several studies identified type of cancer (e.g. breast, lung or prostate cancer) as a significant factor in predicting SCC, but it remains difficult to determine the risk differential partly because of residual bias. Consideration of quantitative results from the studies does not easily allow generation of a coherent numerical summary, studies were heterogeneous especially with regard to population, results were not consistent between studies, and study results almost universally lacked corroboration from other independent studies. CONCLUSION No studies were found which examined natural history. Overall burden of metastatic disease, confirmed metastatic bone involvement and immediate symptomatology suggestive of spinal column involvement are already well known as factors for metastatic SCC, vertebral collapse or progression of vertebral collapse. Although we identified a large number of additional possible prognostic factors, those which currently offer the most potential are unclear. Current clinical consensus favours magnetic resonance imaging and CT imaging modalities for the investigation of SCC and vertebral fracture. Future research should concentrate on: (1) prospective randomised designs to establish clinical and quality-of-life outcomes and cost-effectiveness of identification and treatment of patients at high risk of vertebral collapse and SCC; (2) Service Delivery and Organisation research on magnetic resonance imaging (MRI) scans and scanning (in tandem with research studies on use of MRI to monitor progression) in order to understand best methods for maximising use of MRI scanners; and (3) investigation of prognostic algorithms to calculate probability of a specified event using high-quality prospective studies, involving defined populations, randomly selected and clearly identified samples, and with blinding of investigators. FUNDING This report was commissioned by the National Institute for Health Research Health Technology Assessment Programme NIHR HTA Programme as project number HTA 10/91/01.