Sorafenib therapy decreases the clearance of thyrotropin

OBJECTIVE

Thyroid function abnormalities are common during treatment with tyrosine kinase inhibitors such as sorafenib. Suggested causes are direct effects on thyroid tissue and increased extrathyroidal metabolism of serum thyroxine and 3,5,3-triiodothyronine. We postulated that tyrosine kinase inhibitors may affect the peripheral metabolism of TSH as well. The effect of sorafenib on TSH clearance was studied.

DESIGN

In a study of athyreotic patients on TSH suppression therapy, TSH concentrations were measured after recombinant human TSH (rhTSH) injections before and after 26 weeks of sorafenib therapy.

METHODS

Before and after the last week of sorafenib therapy, 20 patients with progressive differentiated thyroid carcinoma received a standard dose regimen of two injections 0.9 mg rhTSH on two consecutive days. TSH concentrations were measured 48 h (TSH(48 h)) and 96 h (TSH(96 h)) after the first rhTSH injection. The area under the curve (TSH-AUC), reflecting TSH content between 48 and 96 h following rhTSH administration, was calculated.

RESULTS

TSH(48 h) levels (120.5 mU/l before vs 146.3 mU/l after; P=0.029), TSH(96 h) levels (22.0 mU/l before vs 35.5 mU/l after; P=0.001), and TSH-AUC (142.7 vs 186.8 mU/l; P=0.001) were significantly higher after sorafenib treatment. Higher sorafenib doses were associated with increased changes in TSH(96 h) and TSH-AUC. In two patients, TSH levels after sorafenib therapy exceeded 200 mU/l.

CONCLUSIONS

Sorafenib therapy is accompanied by higher rhTSH levels, probably due to a decreased TSH clearance. Further studies are recommended to clarify whether a decreased clearance of TSH is sorafenib specific.

Dietary modulation of plasma angiopoietin-like protein 4 concentrations in healthy volunteers and in patients with type 2 diabetes

BACKGROUND

Angiopoietin-like protein 4 (ANGPTL4) has been identified as an inhibitor of lipoprotein lipase. Preliminary data suggest that plasma nonesterified fatty acids (NEFAs) raise plasma ANGPTL4 concentrations in humans.

OBJECTIVE

The objective was to assess plasma ANGPTL4 concentrations after various nutritional interventions that increase NEFA concentrations in healthy subjects and in patients with type 2 diabetes mellitus.

DESIGN

We studied 4 groups, both at baseline and after 3 d of either fasting (n = 22 healthy men), a very-low-calorie diet (VLCD; n = 10 healthy men and n = 10 patients with diabetes), or a high-fat, high-energy diet (HFED; n = 15 healthy men). Plasma ANGPTL4, NEFA, and triglyceride concentrations were measured.

RESULTS

In healthy men, a VLCD increased ANGPTL4 from 13.2 (IQR: 8.1-24.2) at baseline to 18.2 (16.7-33.4) ng/mL (P < 0.05), fasting increased ANGPTL4 from 10.6 (7.6-17.6) to 28.0 (23.1-35.0) ng/mL (P < 0.05), and an HFED increased ANGPTL4 from 13.9 (8.2-22.0) to 17.2 (11.2-23.6) ng/mL (P < 0.05). In men with diabetes, a VLCD also increased ANGPTL4, from 10.9 ± 2.4 to 19.2 ± 3.2 ng/mL (P < 0.05). All interventions significantly increased plasma NEFAs in both healthy men and patients with diabetes. The change in ANGPTL4 positively correlated with the change in NEFA concentrations (β = 0.048, P < 0.001) and negatively correlated with the change in plasma triglycerides (β = -0.051, P = 0.01).

CONCLUSIONS

Three days of either fasting, a VLCD, or an HFED increased plasma ANGPTL4 concentrations in healthy men, concomitantly with increased plasma NEFA concentrations. Similarly, a VLCD in patients with diabetes increased ANGPTL4 concentrations, concomitantly with increased NEFA concentrations.

Heart rate variability and first cardiovascular event in populations without known cardiovascular disease: meta-analysis and dose-response meta-regression

AIMS

Heart rate variability (HRV) is associated with cardiovascular disease (CVD) in individuals with known CVD. It is less clear whether HRV is associated with a first cardiovascular event. Therefore, we performed a meta-analysis to study the association between HRV and incident cardiovascular events in populations without known CVD.

METHODS AND RESULTS

We performed a meta-analysis and dose-response meta-regression of studies assessing the association between HRV and CVD. We searched Pubmed, Embase, Web of Science, Cochrane library, ScienceDirect, and CINAHL up to December 2011 for eligible studies. We selected studies that used the standard deviation of the normalized N-N interval (SDNN), low-frequency (LF) or high-frequency (HF) spectral component as a measure of HRV. Primary outcomes were (non)fatal cardiovascular events. Eight studies with a total number of 21 988 participants were included. The pooled relative risk (RR) comparing the lowest level to the highest level of SDNN was 1.35 (95% CI 1.10, 1.67). The pooled RRs for LF and HF were 1.45 (95% CI 1.12, 1.87) and 1.32 (95% CI 0.96, 1.81), respectively. In a meta-regression, the predicted RR of incident CVD of the 10th and 90th HRV (SDNN) percentiles compared with the 50th percentile were 1.50 (95% CI 1.22, 1.83) and 0.67 (95% CI 0.41, 1.09).

CONCLUSION

In conclusion, low HRV is associated with a 32-45% increased risk of a first cardiovascular event in populations without known CVD. An increase in SDNN of 1% results in an ∼1% lower risk of fatal or non-fatal CVD.

Relationship between carotid intima media thickness and helminth infections on Flores Island, Indonesia

Objective

To examine the association between helminth infections and atherosclerosis.

Background

Chronic helminth infection, which can lead to poor nutritional status and anti-inflammatory response, might protect against the development of atherosclerosis.

Methods

A cross-sectional study was performed in Flores, Indonesia, an area highly endemic for soil-transmitted helminths (STH). Stool samples from 675 participants aged 18–80 years were collected and screened for Trichuris trichiura by microscopy and for Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale, and Strongyloides stercoralis by qPCR. We collected data on body mass index (BMI), waist to hip ratio (WHR), blood pressure, fasting blood glucose (FBG), lipid, high sensitive C-reactive protein (hs-CRP), total immunoglobulin-E (TIgE) and Escherichia coli lipopolysaccharide stimulated cytokines (tumor necrosis factor and interleukin-10). In a subset of 301 elderly adults (≥40 years of age) carotid intima media thickness (cIMT) was measured.

Results

Participants with any STH infection had lower BMI (kg/m2) (mean difference −0.66, 95%CI [−1.26, −0.06]), WHR (−0.01, [−0.02, −0.00]), total cholesterol (mmol/L) (−0.22, [−0.43, −0.01]) and LDL-cholesterol (mmol/L) (−0.20, [−0.39, −0.00]) than uninfected participants. After additional adjustment for BMI the association between helminth infection and total cholesterol (mean difference −0.17, 95%CI [−0.37, 0.03]) as well as LDL-cholesterol (−0.15, [−0.33, 0.04]) was less pronounced. BMI, WHR, and total cholesterol were negatively associated with number species of helminth co-infections. Participants with high TIgE, an indicator of exposure to helminths, had lower FBG, TC, and HDL. The association between TIgE and TC and HDL remained significant after adjustment with BMI. No clear association was found between STH infection or TIgE and mean cIMT.

Conclusions

This cross-sectional study presents evidence that helminth infections were negatively associated with risk factors for cardiovascular disease, an association at least partially mediated by an effect on BMI. The significance of this finding needs to be determined.

Regression and local control rates after radiotherapy for jugulotympanic paragangliomas: systematic review and meta-analysis

The primary treatment goal of radiotherapy for paragangliomas of the head and neck region (HNPGLs) is local control of the tumor, i.e. stabilization of tumor volume. Interestingly, regression of tumor volume has also been reported. Up to the present, no meta-analysis has been performed giving an overview of regression rates after radiotherapy in HNPGLs. The main objective was to perform a systematic review and meta-analysis to assess regression of tumor volume in HNPGL-patients after radiotherapy. A second outcome was local tumor control. Design of the study is systematic review and meta-analysis. PubMed, EMBASE, Web of Science, COCHRANE and Academic Search Premier and references of key articles were searched in March 2012 to identify potentially relevant studies. Considering the indolent course of HNPGLs, only studies with ≥ 12 months follow-up were eligible. Main outcomes were the pooled proportions of regression and local control after radiotherapy as initial, combined (i.e. directly post-operatively or post-embolization) or salvage treatment (i.e. after initial treatment has failed) for HNPGLs. A meta-analysis was performed with an exact likelihood approach using a logistic regression with a random effect at the study level. Pooled proportions with 95% confidence intervals (CI) were reported. Fifteen studies were included, concerning a total of 283 jugulotympanic HNPGLs in 276 patients. Pooled regression proportions for initial, combined and salvage treatment were respectively 21%, 33% and 52% in radiosurgery studies and 4%, 0% and 64% in external beam radiotherapy studies. Pooled local control proportions for radiotherapy as initial, combined and salvage treatment ranged from 79% to 100%. Radiotherapy for jugulotympanic paragangliomas results in excellent local tumor control and therefore is a valuable treatment for these types of tumors. The effects of radiotherapy on regression of tumor volume remain ambiguous, although the data suggest that regression can be achieved at least in some patients. More research is needed to identify predictors for treatment success.

[Over-the-border evidence: the relevance of results of non-Western RCTs]

Increasing numbers of randomised-controlled trials are performed in non-Western countries. The main reason for this tendency are the lower costs needed to perform trials in non-Western countries. It has been shown that results from trials performed in non-Western countries sometimes overestimate the effects compared to trials with the same intervention performed in Western countries. This means that results from trials performed in non-Western countries are not automatically generalisable to Western countries.

[Instrumental variable analysis]

Instrumental variable analysis is a recently propagated method to deal with confounding and to estimate therapeutic effects in observational studies. An instrumental variable is a factor which affects treatment but is not related to patient prognosis. A theoretical advantage of a well-chosen instrumental variable is that both measured and unmeasured confounders do not influence the effect estimator. Examples of instrumental variables previously used are regional differences in treatment and physician prescribing preference. Application of instrumental variable analysis seems most suited to large patient registries with considerable expected residual confounding in case standard analytical methods are applied.

[Causality: risk factors and interventions]

A risk factor has a causal effect on a disease when the disease would not have occurred in the absence of the risk factor. Analogous reasoning applies to the effect of a particular therapy. Thinking in terms of contrasts is fundamental to causal reasoning in medicine. The contrast determines the content of the causal claim; the most important assumption here is that the prognosis between groups is comparable. Causal effects of risk factors are not always the same as the causal effect of an intervention: removal of a risk factor (e.g. smoking) for a disease does not necessarily mean that the risk will subsequently normalize. A second problem is that risk factors cannot always easily be translated into interventions. This applies to factors that cannot be changed (e.g. gender) or that can have multiple causes themselves (e.g. obesity).

Insulin resistance and risk of incident cardiovascular events in adults without diabetes: meta-analysis

BACKGROUND

Glucose, insulin and Homeostasis Model Assessment Insulin Resistance (HOMA-IR) are markers of insulin resistance. The objective of this study is to compare fasting glucose, fasting insulin concentrations and HOMA-IR in strength of association with incident cardiovascular disease.

METHODS

We searched the PubMed, MEDLINE, EMBASE, Web of Science, ScienceDirect and Cochrane Library databases from inception to March, 2011, and screened reference lists. Cohort studies or nested case-control studies that investigated the association between fasting glucose, fasting insulin or HOMA-IR and incident cardiovascular disease, were eligible. Two investigators independently performed the article selection, data extraction and risk of bias assessment. Cardiovascular endpoints were coronary heart disease (CHD), stroke or combined cardiovascular disease. We used fixed and random-effect meta-analyses to calculate the pooled relative risk for CHD, stroke and combined cardiovascular disease, comparing high to low concentrations of glucose, insulin or HOMA-IR. Study heterogeneity was calculated with the I(2) statistic. To enable a comparison between cardiovascular disease risks for glucose, insulin and HOMA-IR, we calculated pooled relative risks per increase of one standard deviation.

RESULTS

We included 65 studies (involving 516,325 participants) in this meta-analysis. In a random-effect meta-analysis the pooled relative risk of CHD (95% CI; I(2)) comparing high to low concentrations was 1.52 (1.31, 1.76; 62.4%) for glucose, 1.12 (0.92, 1.37; 41.0%) for insulin and 1.64 (1.35, 2.00; 0%) for HOMA-IR. The pooled relative risk of CHD per one standard deviation increase was 1.21 (1.13, 1.30; 64.9%) for glucose, 1.04 (0.96, 1.12; 43.0%) for insulin and 1.46 (1.26, 1.69; 0.0%) for HOMA-IR.

CONCLUSIONS

The relative risk of cardiovascular disease was higher for an increase of one standard deviation in HOMA-IR compared to an increase of one standard deviation in fasting glucose or fasting insulin concentration. It may be useful to add HOMA-IR to a cardiovascular risk prediction model.

Fatigue and fatigue-related symptoms in patients treated for different causes of hypothyroidism

OBJECTIVE

Research on determinants of well-being in patients on thyroid hormone replacement therapy is warranted, as persistent fatigue-related complaints are common in this population. In this study, we evaluated the impact of different states of hypothyroidism on fatigue and fatigue-related symptoms. Furthermore, the relationship between fatigue and the TSH receptor (TSHR)-Asp727Glu polymorphism, a common genetic variant of the TSHR, was analyzed.

DESIGN

A cross-sectional study was performed in 278 patients (140 patients treated for differentiated thyroid carcinoma (DTC) and 138 with autoimmune hypothyroidism (AIH)) genotyped for the TSHR-Asp727Glu polymorphism.

METHODS

The multidimensional fatigue inventory (MFI-20) was used to assess fatigue, with higher MFI-20 scores indicating more fatigue-related complaints. MFI-20 scores were related to disease status and Asp727Glu polymorphism status.

RESULTS

AIH patients scored significantly higher than DTC patients on all five MFI-20 subscales (P<0.001), independent of clinical and thyroid hormone parameters. The frequency of the TSHR-Glu727 allele was 7.2%. Heterozygous DTC patients had more favorable MFI-20 scores than wild-type DTC patients on four of five subscales. The modest effect of the TSHR-Asp727Glu polymorphism on fatigue was found in DTC patients only.

CONCLUSIONS

AIH patients had significantly higher levels of fatigue compared with DTC patients, which could not be attributed to clinical or thyroid hormone parameters. The modest effect of the TSHR-Asp727Glu polymorphism on fatigue in DTC patients should be confirmed in other cohorts.

Outpatient versus inpatient treatment in patients with pulmonary embolism: a meta-analysis

Our aim was to study the safety of outpatient treatment in low risk patients with acute pulmonary embolism compared with inpatient treatment, the current clinical standard. We searched Medline, Web of Science, Cochrane and EMBASE databases and included studies on outpatient treatment of pulmonary embolism. The outcomes were 3-month recurrent venous thromboembolism, major bleeding and all-cause mortality. We identified 13 studies (1657 patients) with outpatients (discharge <24 h), three studies (256 patients) with early discharge patients (discharged within 72 h) and five studies (383 patients) with inpatients. The pooled incidence of recurrent venous thromboembolism was 1.7% (95% CI 0.92-3.1%) in outpatients, 1.1% (0.22-5.4%) in patients discharged early and 1.2% (0.16-8.1%) in inpatients. The pooled incidence of major bleeding was 0.97% (0.58-1.6%) in outpatients, 0.78% (0.16-3.7%) in early discharge patients and 1.0% (0.39-2.8%) in inpatients. The pooled incidence of mortality was 1.9% (0.79-4.6%) in outpatients, 2.3% (1.1-5.1%) in early discharge patients and 0.74% (0.04-11%) in inpatients. Incidences of recurrent venous thromboembolism, major bleeding and, after correction for malignancies, mortality were comparable between outpatients, patients discharged early and inpatients. We conclude that home treatment or early discharge of selected low-risk patients with pulmonary embolism is as safe as inpatient treatment.

Increased levels of free thyroxine and risk of venous thrombosis in a large population-based prospective study

BACKGROUND

Recent studies have shown that high levels of free thyroxine (FT4), even without leading to hyperthyroidism, are associated with a procoagulant state.

OBJECTIVES

The aim of our study was to determine whether high levels of thyroid hormones are associated with an increased risk of venous thrombosis.

PATIENTS/METHODS

From a prospective nested case-cohort design within the second Nord-Trøndelag Health Study (HUNT2) cohort (1995-1997; 66,140 subjects), all patients with venous thrombosis during follow-up (n=515) and 1476 randomly selected age-stratified and sex-stratified controls were included. Relative and absolute risks for venous thrombosis were calculated for different cut-off levels of thyroid hormones on the basis of percentiles in the controls and different times between blood sampling and thombosis.

RESULTS

In subjects with an FT4 level above the 98th percentile (17.3 pmol L(-1)), the odds ratio (OR) was 2.5 (95% confidence interval [CI] 1.3-5.0) as compared with subjects with levels below this percentile. For venous thrombosis within 1 year from blood sampling, this relative risk was more pronounced, with an OR of 4.8 (95% CI 1.7-14.0). Within 0.5 years, the association was even stronger, with an OR of 9.9 (95% CI 2.9-34.0, adjusted for age, sex, and body mass index). For thyroid-stimulating hormone, the relationship was inverse and less pronounced. The absolute risk within 6 months in the population for FT4 levels above the 98th percentile was 6.1 per 1000 person-years (95% CI 1.7-15.7).

CONCLUSIONS

Levels of FT4 at the upper end of the normal range are a strong risk factor for venous thrombosis. The risk increased with higher levels of thyroxine and shorter time between blood sampling and thrombosis. Further studies on the effect of clinical hyperthyroidism are warranted.

Risk of hypothyroidism following hemithyroidectomy: systematic review and meta-analysis of prognostic studies

CONTEXT

The reported risk of hypothyroidism after hemithyroidectomy shows considerable heterogeneity in literature.

OBJECTIVE

The aim of this systematic review and meta-analysis was to determine the overall risk of hypothyroidism, both clinical and subclinical, after hemithyroidectomy. Furthermore, we aimed to identify risk factors for postoperative hypothyroidism.

DATA SOURCES

A systematic literature search was performed using several databases, including PubMed.

STUDY SELECTION

Original articles in which an incidence or prevalence of hypothyroidism after primary hemithyroidectomy could be extracted were included.

DATA EXTRACTION

Study identification and data extraction were performed independently by two reviewers. In case of disagreement, a third reviewer was consulted.

DATA SYNTHESIS

A total of 32 studies were included in this meta-analysis. Meta-analysis was performed using logistic regression with random effect at study level. The overall risk of hypothyroidism after hemithyroidectomy was 22% (95% confidence interval, 19-27). A clear distinction between clinical (supranormal TSH levels and subnormal thyroid hormone levels) and subclinical (supranormal TSH levels and thyroid hormone levels within the normal range) hypothyroidism was provided in four studies. These studies reported on an estimated risk of 12% for subclinical hypothyroidism and 4% for clinical hypothyroidism. Positive anti-thyroid peroxidase status is a relevant preoperative indicator of hypothyroidism after surgery. Effect estimates did not differ substantially between studies with lower risk of bias and studies with higher risk of bias.

CONCLUSIONS

This meta-analysis showed that approximately one in five patients will develop hypothyroidism after hemithyroidectomy, with clinical hypothyroidism in one of 25 operated patients.

Adherence to treatment guidelines and survival in patients with early-stage breast cancer by age at diagnosis

Background

Elderly patients with breast cancer are under-represented in clinical studies. It is not known whether treatment guidelines, based on clinical trials, can be extrapolated to this population. The aim of this study was to assess adherence to treatment guidelines by age at diagnosis, and to examine age-specific survival in relation to adherence to guidelines.

Methods

Patients with early-stage breast cancer aged either less than 65 years, or 75 years or more, diagnosed between 2005 and 2008, were identified from the Netherlands Cancer Registry. Adherence to treatment guidelines for breast and axillary surgery, radiotherapy, chemotherapy and endocrine therapy was determined. Non-adherence to the guidelines was defined as overtreatment or undertreatment. The primary endpoint was overall survival, assessed by means of an instrumental variable, the comprehensive cancer centre region.

Results

Some 24 959 patients younger than 65 years and 6561 patients aged 75 years or more were included in the analysis. Median follow-up was 2·8 years. Compared with patients younger than 65 years, those aged at least 75 years were less frequently treated in concordance with guidelines: 62·0 per cent (15 487 patients) versus 55·6 per cent (3647 patients) (P &lt; 0·001). In both age groups, most patients received at least three of five treatment modalities in concordance with guidelines: 98·8 per cent (24 652 patients) and 93·8 per cent (6152 patients) respectively. Analysis of survival using the instrumental variable showed that adherence to guidelines was not associated with overall survival in patients younger than 65 years (P = 0·601) or those aged at least 75 years (P = 0·190).

Conclusion

Adherence to treatment guidelines was affected by age at diagnosis. However, adherence to the guidelines was not associated with overall survival in either age group.

Distinguishing case series from cohort studies

Case series are a commonly reported study design, but the label "case series" is used inconsistently and sometimes incorrectly. Mislabeling impairs the appropriate indexing and sorting of evidence. This article tries to clarify the concept of case series and proposes a way to distinguish them from cohort studies. In a cohort study, patients are sampled on the basis of exposure and are followed over time, and the occurrence of outcomes is assessed. A cohort study may include a comparison group, although this is not a necessary feature. A case series may be a study that samples patients with both a specific outcome and a specific exposure, or one that samples patients with a specific outcome and includes patients regardless of whether they have specific exposures. Whereas a cohort study, in principle, enables the calculation of an absolute risk or a rate for the outcome, such a calculation is not possible in a case series.

['Non-inferiority' trials. Tips for the critical reader. Research methodology 3]

The aim of non-inferiority trials is to show that a new treatment is not less effective than standard treatment, in other words 'non-inferior'. The non-inferiority margin should be determined before a study commences. This margin determines the maximal magnitude of difference in effectiveness permissible if it is to be concluded that a new treatment is not less effective than the standard treatment. There is usually a good reason for a non-inferiority design. For example, because the new treatment is easier to use, provides better cost-effectiveness or has fewer side effects. The reader of a non-inferiority trial should consider a number of aspects critically: (a) the reason for use of this study design, (b) the assumed benefit of the new treatment, (c) the rationale for the choice of non-inferiority margin and (d) the choice of the standard therapy with which the new treatment is compared.

[The stepped wedge design]

Not all questions concerning therapeutic effects in medical research can be answered satisfactorily by standard trials. The stepped wedge cluster design is a special form of randomised study in which an intervention at group level is implemented in stages. The design can be used in situations where randomization at the patient level is inappropriate or impossible and where a stepped implementation of the experimental intervention is important for ethical, logistic or financial reasons. The time before the experimental intervention is introduced in a cluster is used as control period. The statistical analysis of cluster trials should account for the fact that individuals within clusters may show many similarities. Ethical aspects of stepped wedge design should be considered carefully, especially when obtaining individual informed consent is not possible.

Survival in dialysis patients is not different between patients with diabetes as primary renal disease and patients with diabetes as a co-morbid condition

Background

On dialysis, survival among patients with diabetes mellitus is inferior to survival of non-diabetic patients. We hypothesized that patients with diabetes as primary renal disease have worse survival compared to patients with diabetes as a co-morbid condition and aimed to compare all-cause mortality between these patient groups.

Methods

Data were collected from the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD), a multicenter, prospective cohort study in which new patients with end stage renal disease (ESRD) were monitored until transplantation or death. Patients with diabetes as primary cause of ESRD were compared with patients with diabetes as co-morbid condition and both of these patient groups were compared to patients without diabetes. Analysis was performed using Kaplan-Meier and Cox regression.

Results

Fifteen % of the patients had diabetic nephropathy as primary renal disease (N = 281); 6% had diabetes as co-morbid condition (N = 107) and 79% had no diabetes (N = 1465). During follow-up 42% of patients (N = 787) died. Compared to non-diabetic patients, mortality risk was increased for both patients with diabetes as primary renal disease HR: 1.9 (95% CI 1.6, 2.3) and for patients with diabetes as co-morbid condition HR: 1.7 (95% CI 1.3, 2.2). Mortality was not significantly higher in patients with diabetes as primary renal disease compared to patients with diabetes as co-morbid condition (HR 1.06; 95% CI 0.79, 1.43).

Conclusions

This study in patients with ESRD showed no survival difference between patients with diabetes as primary renal disease and patients with diabetes as a co-morbid condition. Both conditions were associated with increased mortality risk compared to non-diabetic patients.

Meta-analysis: serum creatinine changes following contrast enhanced CT imaging

PURPOSE

Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN.

MATERIALS AND METHODS

A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach.

RESULTS

Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0-8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01-0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6-2.1%). Patients with chronic kidney disease (odds ratio 2.26, p<0.001) or diabetes mellitus (odds ratio 3.10, p<0.001) were at increased risk for the development of CIN.

CONCLUSION

CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted.

Incidence of venous thromboembolism in patients with Cushing's syndrome: a multicenter cohort study

CONTEXT

Venous thrombosis has frequently been reported in patients with endogenous Cushing's syndrome (CS).

OBJECTIVE

The aim of this study was to evaluate the incidence of venous thromboembolism (VTE) in patients with CS prior to treatment and after surgery.

DESIGN AND SETTING

We conducted a multicenter cohort study at all university medical centers in The Netherlands.

PATIENTS

Consecutive patients diagnosed with endogenous CS of benign origin between January 1990 and June 2010 were eligible for inclusion. Patients surgically treated for nonfunctioning pituitary adenoma served as controls for the incidence of postoperative VTE in ACTH-dependent CS.

MAIN OUTCOME MEASURES

We documented all objectively confirmed VTE during 3 yr prior to, and 3 yr after treatment onset. The incidences of VTE were expressed as incidence rates.

RESULTS

A total of 473 patients (mean age 42 yr, 363 women) were included (360 ACTH-dependent pituitary CS). The total number of person-years was 2526. Thirty-seven patients experienced VTE during the study period, resulting in an incidence rate of 14.6 [95% confidence interval (CI) 10.3-20.1] per 1000 person-years. The incidence rate for first-ever VTE prior to treatment was 12.9 (95% CI 7.5-12.6) per 1000 person-years (17 events). The risk of postoperative VTE, defined as risk within 3 months after surgery, was 0% for ACTH-independent and 3.4% (95% CI 2.0-5.9) for ACTH-dependent CS (12 events in 350 patients); most events occurred between 1 wk and 2 months after surgery. Compared with the controls, the risk of postoperative VTE in patients undergoing transsphenoidal surgery was significantly greater (P = 0.01).

CONCLUSIONS

Patients with CS are at high risk of VTE, especially during active disease and after pituitary surgery. Guidelines on thromboprophylaxis are urgently needed.