Endocrinology in the time of COVID-19: Management of pituitary tumours

Patients with pituitary tumours, ensuing hormonal abnormalities and mass effects are usually followed in multidisciplinary pituitary clinics and can represent a management challenge even during the times of non-pandemic. The COVID-19 pandemic has put on hold routine medical care for hundreds of millions of patients around the globe, while many pituitary patients' evaluations cannot be delayed for too long. Furthermore, the majority of patients with pituitary tumours have co-morbidities potentially impacting the course and management of COVID-19 (e.g. hypopituitarism, diabetes mellitus, hypertension, obesity and cardiovascular disease). Here, we summarize some of the diagnostic and management dilemmas encountered, and provide guidance on safe and as effective as possible delivery of care in the COVID-19 era. We also attempt to address how pituitary services should be remodelled in the event of similar crises, while maintaining or even improving patient outcomes. Regular review of these recommendations and further adjustments are needed, depending on the evolution of the COVID-19 pandemic status. We consider that the utilization of successful models of pituitary multidisciplinary care implemented during the COVID-19 pandemic should continue after the crisis is over by using the valuable and exceptional experience gained during these challenging times.

Hair cortisol concentrations in chronic central serous chorioretinopathy

PURPOSE

Central serous chorioretinopathy (CSC), a distinct form of macular degeneration, has been associated with glucocorticoid use and possibly also with an increased endogenous activity of the hypothalamic-pituitary-adrenal (HPA) axis. To estimate long-term glucocorticoid exposure, measurement of hair cortisol concentrations (HCC) has emerged. This cross-sectional study aimed to investigate HCC, as a reflection of chronic endogenous steroid exposure, in a cohort of patients with chronic CSC (cCSC).

METHODS

Hair cortisol concentrations (HCC) were determined in 48 patients with cCSC and 230 population-based controls (Lifelines cohort study), not using exogenous corticosteroids.

RESULTS

Increased HCC (defined as >10.49 pg/mg) were present in 2 (4%) patients with cCSC and 13 (6%) controls. Mean HCC values were not different between patients and controls, and no difference in HCC was found between patients with active cCSC disease and patients with inactive disease. No correlation between HCC and urinary free cortisol (UFC) levels in patients with cCSC was found.

CONCLUSIONS

This study shows that HCC in patients with cCSC are not elevated compared to population-based controls, and no association between HCC and cCSC severity was found. This finding questions the previous suggestion that cCSC is associated with increased HPA axis activity. In line, HCC do not seem useful in monitoring cCSC disease activity.

The epidemiology of aggressive pituitary tumors (and its challenges)

Pituitary tumors are not rare if prevalence rates from autopsy or radiological series are considered; approximately 0.5% of all pituitary adenomas will come to medical attention. Less than 0.1% of these pituitary adenomas will become malignant, and probably around 0.5% of all detected adenomas will display an aggressive course. However, the exact incidence of both aggressive pituitary adenomas and pituitary carcinomas is unknown, as most data come from series with selected patients, such as surgically treated patients, which is likely not a reflection of all patients with a pituitary adenoma. An aggressive pituitary adenoma is not well-defined; even though an overarching definition, capturing both immunohistochemical and clinical characteristics is probably not waterproof, adoption of a widely accepted definition will be very helpful to harmonize research and establish more reliable epidemiological data.

SUN-070 European Registries for Rare Endocrine Conditions (EuRRECa): Results from the Platform for E-reporting of Rare Endocrine Conditions (e-REC)

Background EuRRECa (European Registries for Rare Endocrine Conditions) is a group of web-based projects that work closely with the European Reference Network (ERN) for Rare Endocrine Conditions (endo-ern.eu) and helps the ERN with inventorying its clinical activity. To understand the number of new encounters of rare conditions within this network, it has launched an e-reporting programme for rare endocrine conditions (e-REC) that are covered within this network. Methods 46 endocrine centres within 18 countries volunteered to participate in e-REC from July 2018 to June 2019. An electronic reporting ‘card’ developed through REDcap was issued monthly to enquire whether clinicians had encountered a new case of any condition within the 8 Endo-ERN main thematic groups (MTGs). Results On a monthly basis over 1 year, a median of 14 (range 11, 21) paediatric centres and 13 (11, 25) adult centres actively reported cases. A median of 53 (22, 80) paediatric cases and 96 (42, 250) adult cases were reported monthly. Amongst paediatric cases, conditions within the Sex Development and Maturation (SDM) theme were most commonly reported comprising 38% of all reported conditions, with XY, DSD being the most commonly reported condition (24% of cases). Amongst adults, Pituitary and Thyroid conditions were most commonly reported, 34% and 26% of all conditions, respectively. Amongst conditions within the Pituitary group, pituitary adenoma was the most commonly reported condition (74% of cases) and non-metastatic thyroid carcinoma was the most commonly reported condition (95% of cases) amongst the Thyroid group. In children, the median number of cases reported per centre was 21 (9, 32) for conditions affecting SDM. In adults, a median of 37 (6, 75) Pituitary and 22 (5, 80) Thyroid cases were reported per centre. Conclusion e-REC is a simple, yet effective, platform that can be used to capture information on new encounters with patients with several rare conditions and can be adapted to serve the needs of other discrete networks that are interested in understanding the occurrence of rare conditions.

METHODOLOGY FOR THE ENDOCRINOLOGIST: Basic aspects of confounding adjustment

The results of observational studies of causal effects are potentially biased due to confounding. Various methods have been proposed to control for confounding in observational studies. Eight basic aspects of confounding adjustment are described, with a focus on correction for confounding through covariate adjustment using regression analysis. These aspects should be considered when planning an observational study of causal effects or when assessing the validity of the results of such a study.

Effect of omission of surgery on survival in patients aged 80 years and older with early-stage hormone receptor-positive breast cancer

BACKGROUND

Surgery is increasingly being omitted in older patients with operable breast cancer in the Netherlands. Although omission of surgery can be considered in frail older patients, it may lead to inferior outcomes in non-frail patients. Therefore, the aim of this study was to evaluate the effect of omission of surgery on relative and overall survival in older patients with operable breast cancer.

METHODS

Patients aged 80 years or older diagnosed with stage I-II hormone receptor-positive breast cancer between 2003 and 2009 were selected from the Netherlands Cancer Registry. An instrumental variable approach was applied to minimize confounding, using hospital variation in rate of primary surgery. Relative and overall survival was compared between patients treated in hospitals with different rates of surgery.

RESULTS

Overall, 6464 patients were included. Relative survival was lower for patients treated in hospitals with lower compared with higher surgical rates (90·2 versus 92·4 per cent respectively after 5 years; 71·6 versus 88·2 per cent after 10 years). The relative excess risk for patients treated in hospitals with lower surgical rates was 2·00 (95 per cent c.i. 1·17 to 3·40). Overall survival rates were also lower among patients treated in hospitals with lower compared with higher surgical rates (48·3 versus 51·3 per cent after 5 years; 15·0 versus 19·7 per cent after 10 years respectively; adjusted hazard ratio 1·07, 95 per cent c.i. 1·00 to 1·14).

CONCLUSION

Omission of surgery is associated with worse relative and overall survival in patients aged 80 years or more with stage I-II hormone receptor-positive breast cancer. Future research should focus on the effect on quality of life and physical functioning.

Are placebo controls necessary in controlled human infection trials for vaccines?

Controlled human infection trials, whereby a small group of healthy participants is deliberately exposed to a pathogen under controlled circumstances, can provide preliminary data for vaccine efficacy and for the selection of the most promising candidate vaccines for field trials. Because of the potential harm to participants through the deliberate exposure to a pathogen, the use of smaller groups minimises the cumulative risk. As such, a control group that receives a placebo vaccine followed by controlled exposure to a pathogen should be scientifically well justified. As these types of trials are designed to generate consistent infection rates and thus comparable outcomes across populations and trial sites, data from past studies (historical data) could be used as a valid alternative to placebo groups. In this Personal View, we review this option and highlight the considerations for choosing historical data as a suitable control. For the widespread application of this method, responsibility for the centralisation and sharing of data from controlled human infection trials lies with the scientific community.

Surgery as a Viable Alternative First-Line Treatment for Prolactinoma Patients. A Systematic Review and Meta-Analysis

CONTEXT

The improved remission and complication rates of current transsphenoidal surgery warrant reappraisal of the position of surgery as a viable alternative to dopamine agonists in the treatment algorithm of prolactinomas.

OBJECTIVE

To compare clinical outcomes after dopamine agonist withdrawal and transsphenoidal surgery in prolactinoma patients.

METHODS

Eight databases were searched up to July 13, 2018. Primary outcome was disease remission after drug withdrawal or surgery. Secondary outcomes were biochemical control and side effects during dopamine agonist treatment and postoperative complications. Fixed- or random-effects meta-analysis was performed to estimate pooled proportions. Robustness of results was assessed by sensitivity analyses.

RESULTS

A total of 1469 articles were screened: 55 (10 low risk of bias) on medical treatment (n = 3564 patients) and 25 (12 low risk of bias) on transsphenoidal surgery (n = 1836 patients). Long-term disease remission after dopamine agonist withdrawal was 34% (95% confidence interval [CI], 26-46) and 67% (95% CI, 60-74) after surgery. Subgroup analysis of microprolactinomas showed 36% (95% CI, 21-52) disease remission after dopamine agonist withdrawal, and 83% (95% CI, 76-90) after surgery. Biochemical control was achieved in 81% (95% CI, 75-87) of patients during dopamine agonists with side effects in 26% (95% CI, 13-41). Transsphenoidal surgery resulted in 0% mortality, 2% (95% CI, 0-5) permanent diabetes insipidus, and 3% (95% CI, 2-5) cerebrospinal fluid leakage. Multiple sensitivity analyses yielded similar results.

CONCLUSIONS

In the majority of prolactinoma patients, disease remission can be achieved through surgery, with low risks of long-term surgical complications, and disease remission is less often achieved with dopamine agonists.

Opioids and Their Endocrine Effects: A Systematic Review and Meta-analysis

CONTEXT

The increased use of opioids has resulted in an unprecedented opioid epidemic. Chronic opioid use causes hypogonadism, but its frequency, as well as the effects of opioids on other hypothalamo-pituitary-end organ hormone axes, remains unclear.

OBJECTIVE

The aim of this systematic review and meta-analysis was to assess the effects of opioid use on pituitary function.

METHODS

Eight electronic databases were searched for articles published up to May 8, 2018. Fixed or random effects meta-analysis was performed to estimate pooled proportions with 95% confidence intervals (CI). This study is reported following the PRISMA and MOOSE guidelines.

DATA SYNTHESIS

52 studies (22 low risk of bias) were included describing 18 428 subjects, consisting of patients with chronic pain (n = 21 studies) or on maintenance treatment for opioid addiction (n = 9) and healthy volunteers (n = 4). The most frequently used opioid was methadone (n = 13 studies), followed by morphine (n = 12). Prevalence of hypogonadism was 63% (95% CI: 55%-70%, 15 studies, 3250 patients, 99.5% males). Prevalence of hypocortisolism relying on dynamic and nondynamic testing was 15% (95% CI: 6%-28%, 5 studies, 205 patients, 57.5% males) and including only studies using the insulin tolerance tests 24% (95% CI 16%-33%, 2 studies, n = 97 patients). In 5 out of 7 studies, hyperprolactinemia was present. No clear effects on the somatotropic and hypothalamo-pituitary-thyroid axes were described.

CONCLUSIONS

Hypogonadism occurs in more than half of male opioid users, and hypocortisolism in approximately one-fifth of all patients. Periodical evaluation of at least the gonadal and adrenal axes is therefore advisable.

Assessment of the Clinical Benefit of Imaging in Children With Unilateral Sensorineural Hearing Loss: A Systematic Review and Meta-analysis

Importance

Imaging used to determine the cause of unilateral sensorineural hearing loss (USNHL) in children is often justified by the high likelihood of detecting abnormalities, which implies that these abnormalities are associated with hearing loss and that imaging has a positive contribution to patient outcome or well-being by providing information on the prognosis, hereditary factors, or cause of hearing loss.

Objectives

To evaluate the diagnostic yield of computed tomography (CT) and magnetic resonance imaging (MRI) in children with isolated unexplained USNHL and investigate the clinical relevance of these findings.

Evidence Review

Cochrane Library, Embase, PubMed, and Web of Science databases were searched for articles published from 1978 to 2017 on studies of children with USNHL who underwent CT and/or MRI of the temporal bone. Two authors (F.G.R. and E.N.B.P.) independently extracted information on population characteristics, imaging modality, and the prevalence of abnormalities and assessed the studies for risk of bias. Eligibility criteria included studies with 20 or more patients with USNHL who had CT and/or MRI scans, a population younger than 18 years, and those published in English.

Main Outcomes and Measures

The pooled prevalence with 95% CI of inner ear abnormalities grouped according to finding and imaging modality.

Findings

Of 1562 studies, 18 were included with a total of 1504 participants included in the analysis. Fifteen studies were consecutive case studies and 3 were retrospective cohort studies. The pooled diagnostic yield for pathophysiologic relevant findings in patients with unexplained USNHL was 37% for CT (95% CI, 25%-48%) and 35% for MRI (95% CI, 22%-49%). Cochleovestibular abnormalities were found with a pooled frequency of 19% for CT (95% CI, 14%-25%) and 16% for MRI (95% CI, 7%-25%). Cochlear nerve deficiency and associated cochlear aperture stenosis had a pooled frequency of 16% for MRI (95% CI, 3%-29%) and 44% for CT (95% CI, 36%-53%), respectively. Enlarged vestibular aqueduct (EVA) was detected with a pooled frequency of 7% for CT and 12% for MRI in children with USNHL.

Conclusions and Relevance

Imaging provided insight into the cause of hearing loss in a pooled frequency of about 35% to 37% in children with isolated unexplained USNHL. However, none of these findings had therapeutic consequences, and imaging provided information on prognosis and hereditary factors only in a small proportion of children, namely those with EVA. Thus, there is currently no convincing evidence supporting a strong recommendation for imaging in children who present with USNHL. The advantages of imaging should be carefully balanced against the drawbacks during shared decision making.

Superior Long-term Survival for Simultaneous Pancreas-Kidney Transplantation as Renal Replacement Therapy: 30-Year Follow-up of a Nationwide Cohort

OBJECTIVE

In patients with type 1 diabetes and end-stage renal disease, it is controversial whether a simultaneous pancreas-kidney (SPK) transplantation improves survival compared with kidney transplantation alone. We compared long-term survival in SPK and living- or deceased-donor kidney transplant recipients.

RESEARCH DESIGN AND METHODS

We included all 2,796 patients with type 1 diabetes in the Netherlands who started renal replacement therapy between 1986 and 2016. We used multivariable Cox regression analyses adjusted for recipient age and sex, dialysis modality and vintage, transplantation era, and donor age to compare all-cause mortality between deceased- or living-donor kidney and SPK transplant recipients. Separately, we analyzed mortality between regions where SPK transplant was the preferred intervention (80% SPK) versus regions where a kidney transplant alone was favored (30% SPK).

RESULTS

Of 996 transplanted patients, 42%, 16%, and 42% received a deceased- or living-donor kidney or SPK transplant, respectively. Mean (SD) age at transplantation was 50 (11), 48 (11), and 42 (8) years, respectively. Median (95% CI) survival time was 7.3 (6.2; 8.3), 10.5 (7.2; 13.7), and 16.5 (15.1; 17.9) years, respectively. SPK recipients with a functioning pancreas graft at 1 year (91%) had the highest survival (median 17.4 years). Compared with deceased-donor kidney transplant recipients, adjusted hazard ratios (95% CI) for 10- and 20-year all-cause mortality were 0.79 (0.49; 1.29) and 0.98 (0.69; 1.39) for living-donor kidney and 0.67 (0.46; 0.98) and 0.79 (0.60; 1.05) for SPK recipients, respectively. A treatment strategy favoring SPK over kidney transplantation alone showed 10- and 20-year mortality hazard ratios of 0.56 (0.40; 0.78) and 0.69 (0.52; 0.90), respectively.

CONCLUSIONS

Compared with living- or deceased-donor kidney transplantation, SPK transplant was associated with improved patient survival, especially in recipients with a long-term functioning pancreatic graft, and resulted in an almost twofold lower 10-year mortality rate.

Who is afraid of non-normal data? Choosing between parametric and non-parametric tests

When statistically comparing outcomes between two groups, researchers have to decide whether to use parametric methods, such as the t-test, or non-parametric methods, like the Mann-Whitney test. In endocrinology, for example, many studies compare hormone levels between groups, or at different points in time. Many papers apply non-parametric tests to compare groups. We will explain that non-parametric tests have clear drawbacks in medical research, and, that's the good news, they are often not necessary.

Prevalence of endocrine disorders in obese patients: systematic review and meta-analysis

OBJECTIVE

The increasing prevalence of obesity is expected to promote the demand for endocrine testing. To facilitate evidence guided testing, we aimed to assess the prevalence of endocrine disorders in patients with obesity. The review was carried out as part of the Endocrine Work-up for the Obesity Guideline of the European Society of Endocrinology.

DESIGN

Systematic review and meta-analysis of the literature.

METHODS

A search was performed in MEDLINE, EMBASE, Web of Science and COCHRANE Library for original articles assessing the prevalence of hypothyroidism, hypercortisolism, hypogonadism (males) or hyperandrogenism (females) in patients with obesity. Data were pooled in a random-effects logistic regression model and reported with 95% confidence intervals (95% CI).

RESULTS

Sixty-eight studies were included, concerning a total of 19.996 patients with obesity. The pooled prevalence of overt (newly diagnosed or already treated) and subclinical hypothyroidism was 14.0% (95% CI: 9.7-18.9) and 14.6% (95% CI: 9.2-20.9), respectively. Pooled prevalence of hypercortisolism was 0.9% (95% CI: 0.3-1.6). Pooled prevalence of hypogonadism when measuring total testosterone or free testosterone was 42.8% (95% CI: 37.6-48.0) and 32.7% (95% CI: 23.1-43.0), respectively. Heterogeneity was high for all analyses.

CONCLUSIONS

The prevalence of endocrine disorders in patients with obesity is considerable, although the underlying mechanisms are complex. Given the cross-sectional design of the studies included, no formal distinction between endocrine causes and consequences of obesity could be made.

European Society of Endocrinology Clinical Practice Guideline: Endocrine work-up in obesity

Obesity is an emerging condition, with a prevalence of ~20%. Although the simple measurement of BMI is likely a simplistic approach to obesity, BMI is easily calculated, and there are currently no data showing that more sophisticated methods are more useful to guide the endocrine work-up in obesity. An increased BMI leads to a number of hormonal changes. Additionally, concomitant hormonal diseases can be present in obesity and have to be properly diagnosed - which in turn might be more difficult due to alterations caused by body fatness itself. The present European Society of Endocrinology Clinical Guideline on the Endocrine Work-up in Obesity acknowledges the increased prevalence of many endocrine conditions in obesity. It is recommended to test all patients with obesity for thyroid function, given the high prevalence of hypothyroidism in obesity. For hypercortisolism, male hypogonadism and female gonadal dysfunction, hormonal testing is only recommended if case of clinical suspicion of an underlying endocrine disorder. The guideline underlines that weight loss in obesity should be emphasized as key to restoration of hormonal imbalances and that treatment and that the effect of treating endocrine disorders on weight loss is only modest.

Association Between Levothyroxine Treatment and Thyroid-Related Symptoms Among Adults Aged 80 Years and Older With Subclinical Hypothyroidism

IMPORTANCE

It is unclear whether levothyroxine treatment provides clinically important benefits in adults aged 80 years and older with subclinical hypothyroidism.

OBJECTIVE

To determine the association of levothyroxine treatment for subclinical hypothyroidism with thyroid-related quality of life in adults aged 80 years and older.

DESIGN, SETTING, AND PARTICIPANTS

Prospectively planned combined analysis of data involving community-dwelling adults aged 80 years and older with subclinical hypothyroidism. Data from a randomized clinical trial were combined with a subgroup of participants aged 80 years and older from a second clinical trial. The trials were conducted between April 2013 and May 2018. Final follow-up was May 4, 2018.

EXPOSURES

Participants were randomly assigned to receive levothyroxine (n = 112; 52 participants from the first trial and 60 from the second trial) or placebo (n = 139; 53 participants from the first trial and 86 from the second trial).

MAIN OUTCOMES AND MEASURES

Co-primary outcomes were Thyroid-Related Quality of Life Patient-Reported Outcome (ThyPRO) questionnaire scores for the domains of hypothyroid symptoms and tiredness at 1 year (range, 0-100; higher scores indicate worse quality of life; minimal clinically important difference, 9).

RESULTS

Of 251 participants (mean age, 85 years; 118 [47%] women), 105 were included from the first clinical trial and 146 were included from the second clinical trial. A total of 212 participants (84%) completed the study. The hypothyroid symptoms score decreased from 21.7 at baseline to 19.3 at 12 months in the levothyroxine group vs from 19.8 at baseline to 17.4 at 12 months in the placebo group (adjusted between-group difference, 1.3 [95% CI, -2.7 to 5.2]; P = .53). The tiredness score increased from 25.5 at baseline to 28.2 at 12 months in the levothyroxine group vs from 25.1 at baseline to 28.7 at 12 months in the placebo group (adjusted between-group difference, -0.1 [95% CI, -4.5 to 4.3]; P = .96). At least 1 adverse event occurred in 33 participants (29.5%) in the levothyroxine group (the most common adverse event was cerebrovascular accident, which occurred in 3 participants [2.2%]) and 40 participants (28.8%) in the placebo group (the most common adverse event was pneumonia, which occurred in 4 [3.6%] participants).

CONCLUSIONS AND RELEVANCE

In this prospectively planned analysis of data from 2 clinical trials involving adults aged 80 years and older with subclinical hypothyroidism, treatment with levothyroxine, compared with placebo, was not significantly associated with improvement in hypothyroid symptoms or fatigue. These findings do not support routine use of levothyroxine for treatment of subclinical hypothyroidism in adults aged 80 years and older.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01660126; Netherlands Trial Register: NTR3851.

Effect of different types of statins on kidney function decline and proteinuria: a network meta-analysis

Previous studies showed that statins reduce the progression of kidney function decline and proteinuria, but whether specific types of statins are more beneficial than others remains unclear. We performed a network meta-analysis of randomized controlled trials (RCT) to investigate which statin most effectively reduces kidney function decline and proteinuria. We searched MEDLINE, Embase, Web of Science, and the Cochrane database until July 13, 2018, and included 43 RCTs (>110,000 patients). We performed a pairwise random-effects meta-analysis and a network meta-analysis according to a frequentist approach. We assessed network inconsistency, publication bias, and estimated for each statin the probability of being the best treatment. Considerable heterogeneity was present among the included studies. In pairwise meta-analyses, 1-year use of statins versus control reduced kidney function decline by 0.61 (95%-CI: 0.27; 0.95) mL/min/1.73 m² and proteinuria with a standardized mean difference of -0.58 (95%-CI:-0.88; -0.29). The network meta-analysis for the separate endpoints showed broad confidence intervals due to the small number available RCTs for each individual comparison. In conclusion, 1-year statin use versus control attenuated the progression of kidney function decline and proteinuria. Due to the imprecision of individual comparisons, results were inconclusive as to which statin performs best with regard to renal outcome.

Improvement but No Normalization of Quality of Life and Cognitive Functioning After Treatment of Cushing Syndrome

BACKGROUND

Cushing syndrome is characterized by glucocorticoid excess, which induces physical and mental symptoms, impairments in functional status and perceived health, resulting in impaired quality of life. Biochemical remission is urgently required; however, quality of life and cognitive function may remain impaired.

OBJECTIVE

To perform a systematic review and meta-analysis evaluating changes in health-related quality of life and cognitive functioning in patients with Cushing syndrome after treatment.

METHODS

Eight electronic databases were searched in March 2017, and PubMed again in May 2018, to identify potentially relevant articles. Eligible studies were (randomized controlled) trials, cohort studies, and cross-sectional studies assessing quality of life or cognitive functioning in patients treated for Cushing syndrome. Differences were expressed as standardized mean difference and reported with 95% confidence intervals. We compared patients before and after treatment (improvement) and patients after treatment and healthy controls (normalization).

RESULTS

We included 47 articles with 2643 patients. Most patients had Cushing disease and were in remission after treatment. Quality of life and cognitive functioning improved after treatment in all studied domains. Compared with a healthy control population, quality of life did not normalize. Cognitive functioning normalized in part, but not all, of the studied domains.

CONCLUSIONS

Treatment of Cushing syndrome improves quality of life and cognitive functioning. Because normalization was not achieved in quality of life and in some aspects of cognitive functioning, special and continuous attention should be given to these aspects for patients after treatment. Effective interventions for further improvement and possibly normalization are urgently needed.

Mortality after amputation in dialysis patients is high but not modified by diabetes status

Background

Survival among dialysis patients with diabetes mellitus (DM) is inferior to survival of non-diabetic dialysis patients, probably due to the higher prevalence of diabetes-related comorbid conditions. One could hypothesize that these comorbid conditions also contribute to a decreased survival after amputation in diabetic patients compared with non-diabetic patients on dialysis.

Methods

Data were collected from the Netherlands Cooperative Study on the Adequacy of Dialysis, a multicentre, prospective cohort study in which new patients with end-stage renal disease were monitored until transplantation or death. Amputation rates (incident cases) were calculated in patients with and without DM. The primary endpoint was all-cause survival after first amputation during dialysis therapy in diabetic patients compared with non-diabetic dialysis patients with an amputation. This was formally assessed using interaction analysis (Poisson regression).

Results

During follow-up (mean duration 2.9 years), 50 of the 413 diabetic patients had a new amputation (12.1%), compared with 20 of 1553 non-diabetic patients (1.2%). Amputation rates/1000 person-years were 47.9 [95% confidence interval (CI) 36.3–63.2] and 4.1 (95% CI 2.7–6.4), respectively, for diabetic patients and non-diabetic patients. Amputation increased mortality risk more than 4-fold in patients without diabetes [hazard ratio (HR) 4.6 (95% CI 2.8–7.6)] as well as in patients with diabetes [HR 4.6 (95% CI 3.3–6.4)]. No formal interaction between diabetes and amputation was found (P = 0.12).

Conclusions

Amputation in dialysis patients is associated with a 4-fold increased mortality risk; this mortality risk was similar for diabetes and non-diabetes patients. Importantly, the risk for amputation is 10-fold higher in DM compared with non-diabetic dialysis patients.

Associations of Elevated Antithyroperoxidase Antibodies with Thyroid Function, Survival, Functioning, and Depressive Symptoms in the Oldest Old: The Leiden 85-plus Study

Background: Elevated levels of antithyroperoxidase antibodies (TPOAbs) have been associated with progression of subclinical thyroid dysfunction, extrathyroidal diseases, and decrease in functional status. However, TPOAb as determinant of future thyroid dysfunction and other clinical outcomes has not been studied well for adults aged 85 years and over. This study aimed to assess associations of TPOAb levels with thyroid function, survival, physical function, disability in activities of daily living (ADL), cognitive function, and depressive symptoms in the oldest old. Methods: Data from a population-based cohort study (Leiden 85-plus Study) of residents of Leiden, the Netherlands, aged 85 and older were used. Baseline serum TPOAb levels were available for 488 participants (82% of the total cohort). We considered levels ≥35 IU/mL as elevated. Thyroid function (thyrotropin [TSH] and free thyroxine) was assessed at age 85 (baseline), 87, and 88 years. Survival, physical function, disability in ADL, cognitive function, and depressive symptoms were assessed from age 85 through 90 years. Results: At baseline, 64 of the 85-year old participants (13.1%) had elevated TPOAb levels. They were more often female, had higher TSH levels, and a higher prevalence of overt or subclinical hypothyroidism than participants with normal TPOAb levels. Over time, elevated TPOAb levels were independently associated with a lower mortality risk (hazard ratio 0.72, [95% confidence interval 0.53-0.99]), but were not associated with changes in thyroid function, nor with physical function, disability in ADL, cognitive function, or depressive symptoms. Conclusions: In community-dwelling oldest old, elevated TPOAb levels are cross-sectionally associated with higher TSH levels. Over time, elevated TPOAb levels are associated with a survival benefit but are not associated with changes in thyroid function, functional status, or depressive symptoms in old age. The added clinical value of TPOAb tests in oldest old persons with thyroid dysfunction is limited.

One-stage random effects meta-analysis using linear mixed models for aggregate continuous outcome data

The vast majority of meta-analyses uses summary/aggregate data retrieved from published studies in contrast to meta-analysis of individual participant data (IPD). When the outcome is continuous and IPD are available, linear mixed modelling methods can be employed in a one-stage approach. This allows for flexible modelling of within-study variability and between-study effects and accounts for the uncertainty in the estimates of between-study and within-study residual variances. However, IPD are seldom available. For the normal outcome case, we present a method to generate pseudo IPD from aggregate data using group mean, standard deviation, and sample sizes within each study, ie, the sufficient statistics. Analyzing the pseudo IPD with likelihood-based methods yields identical results as the analysis of the unknown true IPD. The advantage of this method is that we can employ the mixed modelling framework, implemented in many statistical software packages, and explore modelling options suitable for IPD, such as fixed study-specific intercepts and fixed treatment effect model, fixed study-specific intercepts and random treatment effects, and both random study and treatment effects and different options to model the within-study residual variance. This allows choosing the most realistic (or potentially complex) residual variance structures across studies, instead of using an overly simple structure. We demonstrate these methods in two empirical datasets in Alzheimer disease, where an extensive model, assuming all within-study variances to be free, fitted considerably better. In simulations, the pseudo IPD approach showed adequate coverage probability, because it accounted for small sample effects.

Why not to (over)emphasize statistical significance

P values should not merely be used to categorize results into significant and non-significant. This practice disregards clinical relevance, confounds non-significance with no effect and underestimates the likelihood of false-positive results. Better than to use the P value as a dichotomizing instrument, the P values and the confidence intervals around effect estimates can be used to put research findings in a context, thereby taking clinical relevance but also uncertainty genuinely into account.