Relative risks and odds ratios: Simple rules on when and how to use them

Impact of resection margin width on local recurrence following breast-conserving surgery and whole breast radiotherapy for pure ductal carcinoma in situ: a systematic review and meta-analysis

Objective

The aim of this study was to determine the impact of margin width and boost radiotherapy on the local recurrence risk of pure ductal carcinoma in situ (DCIS).

Methods and analysis

This is a prospectively registered systematic review and meta-analysis reporting relative risk (RR), OR and HR margin width outcomes. Eligible studies included prospective and retrospective case series with defining margin widths and 48 months of minimum follow-up. All patients (100%) received adjuvant whole breast radiotherapy (WBRT).

Results

A total of 40 265 patients with pure DCIS in 31 studies were included. ORs and RR were calculated from 15 studies in 12 519 patients, and HRs were calculated from 12 studies in 12 946 patients. Local recurrence was significantly greater with narrower 'close' margins; 0.1-1 mm versus >1 mm in RR (2.88, 95% CI 1.86 to 3.90; p<0.05), OR (4.82, 95% CI 2.45 to 9.48; p<0.05) and HR analysis (1.34, 95% CI 1.01 to 1.67; p<0.05). Compared with margins >2 mm, significantly greater local recurrence was observed in margins 0.1-2 mm in RR (1.72, 95% CI 1.09 to 2.35; p<0.05) and OR (4.43, 95% CI 3.02 to 6.50; p<0.05). Comparing 0.1-1 mm versus >1 mm and 0.1-2 mm versus >2 mm, differences in local recurrence were not statistically significant, once adjusted for boost radiotherapy.

Conclusions

In pure DCIS with WBRT, the local recurrence risk reduces as margin width increases up to 2 mm. The strength of the recommendation for a minimum clear margin of 2 mm is limited by a lack of data comparing 1.1-2 mm with >2 mm. The association between recurrence and close margins is not significant following boost radiotherapy, suggesting a possible alternative to re-excision in patients with close margins <2 mm.

Systematic review registration

CRD42022308524.

Silicone Irregular Hexagon Pessary Versus Polyvinyl Chloride Ring Pessary for Pelvic Organ Prolapse: Randomised Controlled Trial

INTRODUCTION AND HYPOTHESIS

Vaginal pessaries are the mainstay of the non-surgical management of pelvic organ prolapse (POP). A flexible silicone irregular hexagonal (SIH) pessary was developed based on the results of a prior vaginal case study. We hypothesised that the SIH pessary would have a higher rate of retention and self-management than the polyvinyl chloride (PVC) pessary.

METHODS

This was a prospective non-blinded, randomised controlled trial with institutional review board approval. Eligible participants were randomised and fitted with the assigned pessary. They were reviewed 1 week, 6 months and 1 year after the initial pessary fitting. Participants who returned for follow-up completed the study questionnaires. The primary outcome was success, defined as continued use of the allocated pessary at 6 months. Secondary outcomes included the ability to perform pessary self-care, treatment satisfaction and pessary-related complications. Statistical tests were performed with alpha or statistical significance defined as a p value of ≤ 0.05, two-tailed.

RESULTS

A total of 104 participants were randomised, with 52 subjects in each arm. Primary outcome data were analysed using per protocol analysis. Continuing pessary usage at 6 months was 68.1% for the PVC pessary group and 65.1% for the SIH group, with no statistically significant differences between the two groups (p = 0.765). Subjects with SIH were more likely to perform pessary self-care. There were no significant differences in subjects' satisfaction, quality-of-life scores or treatment complications between groups.

CONCLUSIONS

The pessary continuation rate between the SIH and the PVC pessary groups was similar at 6 months. Participants with an SIH pessary were more likely to self-manage.

Testosterone levels and risk of newly diagnosed type 2 diabetes mellitus in adult men: systematic review and meta-analysis

INTRODUCTION

Testosterone is a metabolically active hormone in males for metabolic homeostasis. Although the coexistence of low testosterone levels and type 2 diabetes mellitus (T2DM) have been associated, there are no reports that evaluate alterations in total testosterone (TT) levels and the risk of newly diagnosed T2DM. This review evaluates this question in adult men with high or low levels of total testosterone (TT), as well as the role played by other hormones such as free testosterone (FT), sex hormone binding globulin (SHBG), dihydrotestosterone (DHT), estrogens and testosterone bioavailable (bT).

METHODS

We searched for studies published up to July 30, 2023, in five databases, following a PECO strategy. We found twenty-two studies for quantitative analysis and meta-analyzed the same quantity of studies.

RESULTS

This first meta-analysis incorporates the assessment of the risk of low TT and T2DM in longitudinal studies. 43,038 adult men are included. Our meta-analysis shows that there is an association between low TT levels and the risk of newly diagnosed T2DM (OR 1.52; 95% CI 1.10-2.10; p < 0.05; I²: 79%). It is also evident that SHBG in low TT studies behaves as a risk factor for T2DM in the same way as FT, although without statistical significance. bT behaves as a protective factor. There is no association between estrogen, DHT and T2DM.

CONCLUSIONS

In adult men with low TT values, there is a greater risk of developing a newly diagnosed of T2DM. SHBG values in low TT patients also present a higher risk of T2DM as the same FT but without statistical significance. bT behaves as a protective factor We have not found an association between risk of T2DM and the levels of estrogen, DHT although there are very few studies that report these hormones.

South of the UES: Improving the ability of speech-language pathologists to detect oesophageal abnormalities during videofluoroscopy swallowing studies

PURPOSE

With two-thirds of adults presenting for a videofluoroscopy swallow study (VFSS) with oesophageal abnormalities, it seems prudent to include visualisation of the oesophagus, in the context of the entire swallow process, to provide further information to the diagnostic team. This study aims to evaluate the ability of speech-language pathologists (SLPs) to interpret oesophageal sweep on VFSS and the relative improvement in that ability with additional training.

METHOD

One hundred SLPs attended training in oesophageal visualisation during VFSS, based on a previous study. Ten oesophageal sweep videos (five normal, five abnormal) with one 20 ml thin fluid barium bolus (19% w/v) were presented at baseline and following training. Raters were blinded to patient information other than age. Binary ratings were collected for oesophageal transit time (OTT), presence of stasis, redirection, and referral to other specialists.

RESULT

Inter-rater reliability as measured by Fleiss' kappa improved for all parameters, reaching statistical significance for OTT (pre-test kappa = 0.34, post-test kappa = 0.73; p < 0.01) and redirection (pre-test kappa = 0.38, post-test kappa = 0.49; p < 0.05). Overall agreement improved significantly (p < 0.001) for all parameters except stasis, where improvement was only slight. Interaction between pre-post and type of video (normal/abnormal) was statistically significant (p < 0.001) for redirection, with a large pre-post increase in positive accuracy compared with a slight pre-post decrease in negative accuracy.

CONCLUSION

Findings indicate that SLPs require training to accurately interpret an oesophageal sweep on VFSS. This supports the inclusion of education and training on both normal and abnormal oesophageal sweep patterns, and the use of standardised protocols for clinicians using oesophageal visualisation as part of the VFSS protocol.

High pain reported at 3 months post-total knee arthroplasty often persists for the next 3 years and is associated with reduced function and quality of life

BACKGROUND AND AIMS

Five to ten percent of people having a knee arthroplasty for osteoarthritis continue to experience high pain levels more than 3 months after surgery. The primary aim of this study was to determine the relative risk (RR) of having high pain at 12 and 36 months based on the presence of high pain at 3 and 12 months, respectively.

METHODS

A retrospective analysis of data from a prospective study of participants who had a total knee arthroplasty for osteoarthritis. A score of ≤14 on the Oxford Knee Pain Subscale was defined as 'High Pain', and RRs were calculated comparing those with high or low pain.

RESULTS

There were 718 participants and 13.8% reported high pain at any time point, 2.5% reported high pain at all time points and 10.3% and 4.7% and 6.6% reported high pain at 3-, 12- and 36-months, respectively, post-surgery. For participants with high pain at 3 months, 33.8% had high pain at 12 months with a RR of 24.2 (95% CI 11.7-49.8, p < 0.001) and 35.1% had high pain at 36 months with a RR of 10.8 (95% CI 6.4-18.2, p < 0.001). For participants with high pain at 12 months, 67.6% had high pain at 36 months, with a RR of 19.3 (95% CI 12.2-30.4, p < 0.01).

CONCLUSIONS

Although high pain rates are low overall following knee arthroplasty, once high pain is established there is an elevated RR of it persisting at 12- and 36 months post-surgery.

TRIAL REGISTRATION

The data were collected in the Evidence-based Processes and Outcomes of Care (EPOC) study, ClinicalTrials.gov Identifier: NCT01899443.

Effect of calcium-channel blockers on the risk of active tuberculosis and mortality: systematic review and meta-analysis

Introduction: Recent studies suggest that calcium channel blockers (CCBs) could reduce the risk of active tuberculosis and improve clinical outcomes. We aimed to synthesize the evidence regarding the effect of CCBs on the risk of developing active tuberculosis and mortality. Methods: We systematically searched for observational studies and clinical trials published in six databases until 31 August 2023, following a PECO/PICO strategy. Results: We included eight observational studies, 4,020,830 patients, among whom 241,761 had diabetes mellitus and 30,397 had active tuberculosis. According to our results, CCBs reduce the risk of developing active tuberculosis by 29% (RR 0.71; 95% CI 0.67-0.75) in patients with and without diabetes mellitus. However, CCBs do not show any benefit in terms of tuberculosis-related mortality (RR 1.00; 95% CI 0.98-1.02). For both outcomes, no statistical heterogeneity was found (I2 = 0, p > 0.10). This protective effect of CCBs on the risk of active tuberculosis remained independent of the type of patient (with diabetes mellitus vs. general population) or the class of CCB administered (DHP-CCB vs. non-DHP-CCB) (test for subgroup differences I2 = 0, p > 0.10). However, this beneficial effect was more significant among the general population (RR 0.70; 95% CI 0.66-0.74) compared to patients with diabetes mellitus (RR 0.72; 95% CI 0.61-0.86) and among those patients treated with DHP-CCBs (RR 0.69; 95% CI 0.63-0.74) compared to patients treated with non-DHP-CCBs (RR 0.72; 95% CI 0.67-0.78). Conclusion: CCBs may reduce the risk of active TB in patients with diabetes and the general population. On the contrary, CCBs do not seem to have a protective effect on tuberculosis-related mortality. However, more evidence is still needed. We recommend developing clinical trials to verify these findings, including more diverse populations. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=352129].

SGLT-2 inhibitors and prevention of contrast-induced nephropathy in patients with diabetes undergoing coronary angiography and percutaneous coronary interventions: systematic review and meta-analysis

Introduction

SGLT2 inhibitors (SGLT2Is) have demonstrated cardioprotective and nephroprotective effects in patients with and without diabetes. Recent studies suggest that SGLT2Is may reduce the risk of contrast-induced nephropathy (CIN) in patients with diabetes undergoing coronary arteriography (CAG) or percutaneous coronary interventions (PCI). However, the evidence is still inconclusive. We aimed to systematically review the evidence regarding the potential nephroprotective role of SGLT2Is in preventing CIN in this population.

Methods

We searched for studies in six databases published up to September 30, 2023, following a PECO/PICO strategy. Initially, we meta-analyzed five studies, but due to several reasons, mainly methodological concerns, we excluded one RCT. In our final meta-analysis, we included four observational studies.

Results

This meta-analysis comprised 2,572 patients with diabetes undergoing CAG or PCI, 512 patients treated with SGLT2Is, and 289 events of CIN. This is the first meta-analysis demonstrating that SGLT2Is may reduce the risk of developing CIN by up to 63% (RR 0.37; 95% CI 0.24-0.58) in patients with diabetes undergoing CAG or PCI, compared to not using SGLT2Is. Statistical heterogeneity was not significant (I2 = 0%, p = 0.91). We assessed the certainty of the evidence of this systematic review and meta-analysis, according to the GRADE criteria, as moderate.

Conclusion

SGLT2Is significantly reduce the risk of CIN by up to 63% in patients with diabetes undergoing CAG or PCI. Clinical trials are needed; several are already underway, which could confirm our findings and investigate other unresolved issues, such as the optimal dose, type, and duration of SGLT2 inhibitor therapy to prevent CIN.

Systematic Review

PROSPERO, identifier CRD42023412892.

Impact of the COVID-19 pandemic on the incidence and clinical outcomes of diabetic ketoacidosis among male and female children with type 1 diabetes: systematic review and meta-analysis

Background: Some studies suggest that the SARS-CoV-2 pandemic increased the incidence of type 1 diabetes mellitus (T1DM) and diabetic ketoacidosis (DKA). However, the impact of this pandemic on pediatric T1DM is still mostly unknown. Therefore, we aimed to assess the effect of the COVID-19 pandemic on clinical outcomes in children with T1DM. Methods: We systematically searched for six databases up to 31 August 2022. We included 46 observational studies, 159,505 children of both sexes with T1DM, and 17,547 DKA events. Results: The COVID-19 pandemic significantly increased, in both sexes, the incidence of 1) DKA (OR 1.68; 95% CI 1.44-1.96), 2) severe DKA (OR 1.84; 95% CI 1.59-2.12), 3) DKA in newly diagnosed T1DM (OR 1.75; 95% CI 1.51-2.03), and 4) ICU admissions (OR 1.90; 95% CI 1.60-2.26). However, we did not find a significant association between this pandemic and 1) the incidence of T1DM, 2) the incidence of DKA in established T1DM, 3) the incidence of KDA complications, 4) the length of hospitalization stay, and 5) mortality. Subgroup analysis showed that the study design and the continent of origin accounted for the heterogeneity. Conclusions: The pandemic SARS-CoV-2 raised, in both sexes, the risk of DKA, severe DKA, DKA de novo, and ICU admissions.

Effect of Oral Antidiabetic Drugs on Tuberculosis Risk and Treatment Outcomes: Systematic Review and Meta-Analysis

Tuberculosis and diabetes mellitus are two global pandemics and rising public health problems. Recent studies suggest that oral antidiabetic drugs (OADs) could reduce the risk of tuberculosis and improve clinical outcomes. However, the evidence is controversial. Therefore, we aimed to assess the effect of OADs on the risk of tuberculosis and treatment outcomes. We systematically searched for six databases from inception to 31 August 2022. We followed a predefined PICO/PECO strategy and included two randomized controlled trials and sixteen observational studies. This study collects 1,109,660 participants, 908,211 diabetic patients, and at least 13,841 tuberculosis cases. Our results show that metformin decreases the risk of active tuberculosis by 40% (RR 0.60; 95% CI 0.47-0.77) in diabetic patients. In addition, metformin exhibits a dose-response gradient (medium doses reduce the risk of active tuberculosis by 45%, while high doses reduce this risk by 52%). On the other hand, DPP IV inhibitors increase the risk of active tuberculosis by 43% (RR 1.43; 95% CI 1.02-2.02). Subgroup analysis showed that study design and metformin dose accounted for the heterogeneity. We conclude that metformin significantly protects against active tuberculosis among diabetic patients. On the contrary, DPP IV inhibitors could increase the risk of developing active tuberculosis.

Threats to public figures and association with approach, as a proxy for violence: The importance of grievance

The adoption of the term grievance-fuelled violence reflects the fact that similarities exist between those committing violent acts in the context of grievance in different settings, so potentially allowing the application of insights gained in the study of one group to be applied to others. Given the low base rate of violence against public figures, studies in the field of violence against those in the public eye have tended to use, as a proxy for violence, attempts by the individuals concerned to achieve unwarranted and unwanted proximity to the subject of their attention, given that approach is a necessary prerequisite for most forms of attack. In such studies, one factor that has frequently been considered is whether the making of threats is associated with a subsequent approach. The results have been varied, with no correlation found in some, a negative correlation in others, and a positive correlation in at least one. Such studies have been retrospective, using case files prepared for other purposes, and samples of cases have been selected according to their victims’ sector of employment – for instance, politicians, celebrities, judiciary, and the corporate world. This study of a sample of 126 threat assessment cases, using a prospective methodology, looks at the associations between the making of threats and subsequent approach from a different angle – that of a standardised and validated classification of underlying motivation. It finds that particular types and forms of threat are significantly associated with subsequent approach in cases that are fuelled by grievance, but not in those with the motivation of seeking a relationship. Furthermore, when a sample with a mixture of motivational categories was examined in the manner of previous studies, such associations with threat were not apparent. These results refine the existing understanding of the significance of threats in public-facing cases. Future research projects in this area might usefully incorporate the consideration of underlying motivation, in particular grievance.

Is inpatient rehabilitation a predictor of a lower incidence of persistent knee pain 3-months following total knee replacement? A retrospective, observational study

Background

Moderate to severe levels of persistent knee pain have been estimated to affect up to 25% of people 3-months or more after a total knee replacement. It is unknown whether the type of rehabilitation pathway is associated with persistent high pain after surgery. Using a prospectively followed Australian cohort who underwent total knee replacement for knee osteoarthritis, this study aimed to i) report the incidence of high-intensity knee pain (defined as a score ≤ 15 on the Oxford Knee Score pain subscale) across time and ii) identify whether referral to inpatient rehabilitation was one of the predictors of persistent pain at 3-months post-surgery.

Methods

A retrospective analysis of a large prospective study was conducted using the Oxford Knee Score pain subscale to determine if participants had high pain at 3-months, 12-months and 36-months post-surgery. Relative risks for high pain at 3-, 12- and 36-months between the type of rehabilitation pathway were determined using Poisson multivariable regression with robust standard errors. The same technique was also employed to determine potential predictors, including rehabilitation pathway, of high pain at 3 months.

Results

The incidence of high pain in all participants was 73% pre-surgery and 10, 5 and 6% at 3-, 12- and 36-months respectively following knee replacement. There was a significant interaction between time and rehabilitation pathway, suggesting that the effect of the rehabilitation pathway varied across time. The incidence of high pain at 3-months did not significantly differ between those who attended inpatient rehabilitation (11.6%) and those discharged directly home (9.5%). Multivariable Poisson regression analysis identified the pre-surgical presence of high pain, co-morbid low back pain or other lower limb problem, younger age and having a major complication within 3-months following surgery as significant predictors of persistent pain whilst discharge to inpatient rehabilitation was not.

Conclusion

A small but clinically significant minority of people continued to have high pain levels at 3-, 12- and 36-months following a primary total knee replacement for osteoarthritis. Participation in an inpatient rehabilitation program does not appear to be an important predictor of ongoing knee pain.

Trial registration

The data were collected in the Evidence-based Processes and Outcomes of Care (EPOC) study, ClinicalTrials.gov Identifier: NCT01899443

Further insights into to the role of statins against active tuberculosis: systematic review and meta-analysis

OBJECTIVES

Tuberculosis is a major cause of global morbidity and mortality. Statins could be associated with a lower risk of some infectious diseases, including tuberculosis. Statins could reduce the risk of latent tuberculosis infection and active tuberculosis, acting as an adjuvant in treating tuberculosis. This study aimed to determine if statins reduce the risk of active tuberculosis.

METHODS

We systematically analyzed 8 databases from inception to December 2021. We included articles without language restriction if they met our inclusion and exclusion criteria and the PECO strategy (Population: adults without active pulmonary tuberculosis; Exposure: treatment with any statin; Comparator: no use of statins; Outcome: active tuberculosis). Odds Ratios (ORs) with 95% confidence intervals (CIs) were pooled using random- effects models regardless of heterogeneity quantified by Cochran's Q and I² statistics. We performed subgroup analyses according to the participants' diabetic status and follow-up length (≤10 years or >10 years).

RESULTS

Twelve articles reporting observational studies involving 3.038.043 participants, including at least 32.668 cases of active tuberculosis. Eight reported retrospective cohort studies, three nested case-control study, and one was a case control study.According to our meta-analysis, statins may reduce the risk of active tuberculosis, in the general population (OR 0.66; 95% CI, 0.54-0.81), in non-diabetic (OR 0.66; 95% CI, 0.54-0.80) and in diabetic patients (OR 0.65; 95% CI, 0.49-0.87). This protective effect did not differ according to the participants' diabetic status nor follow-up length (test for subgroup differences I²=0). We found significant clinical and methodological heterogeneity. Similarly, the forest plot, and the I² and Chi² statistics suggested considerable statistical heterogeneity (I²=95%, p<0.05, respectively). Of the 12 included studies, 9 were at low risk of bias and 3 were at high risk of bias. Similarly, according to the funnel plot, it is very likely that there are important publication biases.

CONCLUSION

Statin use may significantly reduce the risk of tuberculosis in the general population, diabetic and non-diabetic patients. Nevertheless, caution should be exercised when interpreting these conclusions, due to the quality of the evidence, the heterogeneity of the studies, the presence of bias, and the difficulty in extrapolating these results to populations of other races and ethnicities.

Prenatal Vitamins and the Risk of Offspring Autism Spectrum Disorder: Systematic Review and Meta-Analysis

Prenatal nutrition is associated with offspring autism spectrum disorder (herein referred to as autism), yet, it remains unknown if the association is causal. Triangulation may improve causal inference by integrating the results of conventional multivariate regression with several alternative approaches that have unrelated sources of bias. We systematically reviewed the literature on the relationship between prenatal multivitamin supplements and offspring autism, and evidence for the causal approaches applied. Six databases were searched up to 8 June 2020, by which time we had screened 1309 titles/abstracts, and retained 12 articles. Quality assessment was guided using Newcastle-Ottawa in individual studies, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) for the body of evidence. The effect estimates from multivariate regression were meta-analysed in a random effects model and causal approaches were narratively synthesised. The meta-analysis of prenatal multivitamin supplements involved 904,947 children (8159 cases), and in the overall analysis showed no robust association with offspring autism; however, a reduced risk was observed in the subgroup of high-quality observational studies (RR 0.77, 95% CI (0.62, 0.96), I2 = 62.4%), early pregnancy (RR 0.76, 95% CI (0.58; 0.99), I2 = 79.8%) and prospective studies (RR 0.69, 95% CI (0.48, 1.00), I2 = 95.9%). The quality of evidence was very low, and triangulation was of limited utility because alternative methods were used infrequently and often not robustly applied.