Prediction Under Interventions: Evaluation of Counterfactual Performance Using Longitudinal Observational Data

Predictions under interventions are estimates of what a person's risk of an outcome would be if they were to follow a particular treatment strategy, given their individual characteristics. Such predictions can give important input to medical decision-making. However, evaluating the predictive performance of interventional predictions is challenging. Standard ways of evaluating predictive performance do not apply when using observational data, because prediction under interventions involves obtaining predictions of the outcome under conditions that are different from those that are observed for a subset of individuals in the validation dataset. This work describes methods for evaluating counterfactual performance of predictions under interventions for time-to-event outcomes. This means we aim to assess how well predictions would match the validation data if all individuals had followed the treatment strategy under which predictions are made. We focus on counterfactual performance evaluation using longitudinal observational data, and under treatment strategies that involve sustaining a particular treatment regime over time. We introduce an estimation approach using artificial censoring and inverse probability weighting that involves creating a validation dataset mimicking the treatment strategy under which predictions are made. We extend measures of calibration, discrimination (c-index and cumulative/dynamic AUCt) and overall prediction error (Brier score) to allow assessment of counterfactual performance. The methods are evaluated using a simulation study, including scenarios in which the methods should detect poor performance. Applying our methods in the context of liver transplantation shows that our procedure allows quantification of the performance of predictions supporting crucial decisions on organ allocation.

Risk factors for oral mucositis in patients with solid tumors under treatment with cetuximab: a retrospective cross-sectional study

BACKGROUND

This study retrospectively analyzed the risk factors for oral mucositis (OM) during cetuximab treatment.

MATERIAL AND METHODS

We screened patients using cetuximab and retrospectively evaluated the presence of OM based on medical records. We collected information from 2 years of evaluations. Patient medical records were reviewed to obtain data on chemotherapy cycle and dose, sex, age, primary tumor, TNM stage, and head and neck radiotherapy (HNR) history. The X2 test and multinomial logistic regression were used for statistical analysis (SPSS 20.0, p < 0.05).

RESULTS

Among 1831 patients, OM was showed in 750 in any grade (41%), during cetuximab treatment. Most patients were female (n=944, 51.6%), <70years-old (n=1149, 62.8%), had larynx cancer (n=789, 43.1%) in T4 (n=579, 47.7%), N0 (n=509, 52.6%) stages. Primary tumor surgery was performed in 1476 (80.6%) patients, radiotherapy in 606 (33.1%) patients and cetuximab protocols most used involved up to four cycles (n=1072, 58.5%) of <400mg (n=996, 54.4%) cetuximab doses. Female (OR [odds ratio] = 2.17, CI95% = 1.26-3.75), >70 years-old patients (OR = 16.02, CI95% = 11.99-21.41), with HHNR (OR = 1.84, 1.41-2.40), treated with >4 cycles (OR = 1.52, CI95% = 1.16-2.01) and high doses of cetuximab (OR = 3.80, CI95% = 2.52-5.71) are the greatest risk factors for OM.

CONCLUSIONS

Since the clinical benefit of cetuximab in the treatment of older patients is limited and there is a high OM, especially in women with head and neck treated with radiotherapy, high doses and a high number of cetuximab cycles must be administered with caution.

Trends in pain undertreatment among lung cancer patients at the EOL: Analysis of urban city medical insurance data in China

BACKGROUND

Cancer-related pain is one of the common priority symptoms in advanced lung cancer patients at the end-of-life (EOL). Alleviating pain is undoubtedly a critical component of palliative care in lung cancer. Our study was initiated to examined trends in opioid prescription-level outcomes as potential indicators of undertreated pain in China.

METHODS

This study used data on 1330 patients diagnosed with lung cancer of urban city medical insurance in China who died between 2014 and 2017. Opioid prescription-level outcomes were determined by annual trends of the proportion of patients filling an opioid prescription, the total dose of opioids filled by decedents, and morphine milligram equivalents per day (MMED) at the EOL (defined as the 60 days before death). We further analyzed monthly changes in the number of opioid prescriptions filled, MMED, and mean daily dose of opioids per prescription (MDDP) of the last 60 days of life by year at death and age, respectively.

RESULTS

A total of 959 patients with exact dates of death were included, with 432 cases (45.06%; 95% CI: 44.36%-45.77%) receiving at least one opioid prescription at the EOL. The declining trends were shown in the proportion of patients filling any opioid prescription, the total dose of opioids filled by decedents and MMED, with an annual decrease of 0.341% (p = 0.01), 104.23 mg (p = 0.011) and 2.84 mg (p = 0.014), respectively. Within the 31-60 days to the 0-30 days of life, the MMED declined 6.08 mg (95% CI: -7.14 to -5.03; p = 0.000351), while the number of opioid prescriptions rose 0.66 (95% CI: 0.160-1.16; p = 0.025). Like the MMED, the MDDP fell 4.11 mg (95% CI: -5.86 to -2.37; p = 0.005) within the last month before death compared to the previous month.

CONCLUSION

Terminal lung cancer populations in urban China have experienced reduced access to opioids at the EOL. The clinicians did not prescribe a satisfactory dose of opioids per prescription, while the patients suffered increasing pain in the last 30 days of life. Sufficient opioid analgesic administration should be advocated for lung cancer patients during the EOL period.

Does the risk of basal cell carcinoma increase in patients with psoriasis under treatment?

BACKGROUND

Psoriasis is a common, chronic, inflammatory disease. Although it mainly affects the skin, it has been associated with a large number of comorbidities. In addition to comorbidities such as depression and psoriatic arthritis, it is known that there is an increased prevalence of cancer in psoriasis patients. Skin cancers, particularly squamous cell carcinoma, have been associated with psoriasis. However, basal cell carcinoma data are limited.

METHODS

346 psoriasis patients and 306 individuals were selected as the control group. There were no differences between the patient and control groups in terms of age and gender. The mean age of the psoriasis patients was 49.9 ± 15.8 years and the control group was 49.4 ± 13.4 years. Sociodemographic data of the patients were recorded. Pharmacological agents used in the treatment of psoriasis were included in the analysis. Disease severity was assessed by the psoriasis area severity index (PASI). In the physical examination of the patients, biopsies were taken from lesions suspicious for BCC. BCC diagnosis was made by histopathologically.

RESULTS

The frequency of BCC was higher in psoriasis patients than in the control group (6.6% vs. 2.9%, p < .001). Advanced age (p < .001), smoking (p = .003), and arthritis (p < .001) were associated with BCC in psoriasis patients. However, there was no relationship between PASI and BCC (p = .142). Among the psoriasis treatments, only UV therapy was associated with BCC (p = .038). The frequency of PUVA (p < .001) and number of PUVA session (p = .010) was higher in psoriasis patients with BCC rather than NB-UVB.

CONCLUSION

The frequency of BCC is increased in psoriasis patients. Psoriasis is associated with an increased risk of BCC, especially when treated with PUVA therapy for a long time.

What are the consequences of over and undertreatment of type 2 diabetes mellitus in a frail population? A systematic review

AIMS

This review aims to identify the evidence base for the consequences of over and undertreatment of type 2 diabetes mellitus in a frail population.

METHOD

In this systematic review, we searched MEDLINE, Embase, PubMed, CINAHL and the Cochrane Library for studies from January 2001 to 15th August 2022. We included a variety of study types that assessed and reported frailty including patients ≥18 years old. Studies included those that reported the prevalence of over or undertreatment of diabetes mellitus in a frail population and those examining outcomes related to glucose control in frail older people living with diabetes. Data were extracted using a bespoke extraction table using a narrative synthesis approach.

RESULTS

A total of 4114 articles were identified with 112 meeting inclusion criteria. These included 15,130 participants across the 11 studies with sample sizes ranging from 101 to 11,140. Several areas were identified in the included studies where under or overtreatment of diabetes impacted outcomes for patients. These included hospital admissions, readmissions, length of stay, falls, mortality, cognitive impairment and cardiovascular disease outcomes.

CONCLUSION

The results showed that there was a high heterogeneity of outcomes between the studies and that many examined small numbers of participants. In this review, both over and undertreatment were shown to increase adverse outcomes in frail older people. Further research around optimal glycaemic control for frail older people living with diabetes is required with the aim to identify ideal target ranges and produce practical clinical guidelines to promote attainment of these.

On minimising tumoural growth under treatment resistance

Drug resistance is a major challenge for curative cancer treatment, representing the main reason of death in patients. Evolutionary biology suggests pauses between treatment rounds as a way to delay or even avoid resistance emergence. Indeed, this approach has already shown promising preclinical and early clinical results, and stimulated the development of mathematical models for finding optimal treatment protocols. Due to their complexity, however, these models do not lend themself to a rigorous mathematical analysis, hence so far clinical recommendations generally relied on numerical simulations and ad-hoc heuristics. Here, we derive two mathematical models describing tumour growth under genetic and epigenetic treatment resistance, respectively, which are simple enough for a complete analytical investigation. First, we find key differences in response to treatment protocols between the two modes of resistance. Second, we identify the optimal treatment protocol which leads to the largest possible tumour shrinkage rate. Third, we fit the "epigenetic model" to previously published xenograft experiment data, finding excellent agreement, underscoring the biological validity of our approach. Finally, we use the fitted model to calculate the optimal treatment protocol for this specific experiment, which we demonstrate to cause curative treatment, making it superior to previous approaches which generally aimed at stabilising tumour burden. Overall, our approach underscores the usefulness of simple mathematical models and their analytical examination, and we anticipate our findings to guide future preclinical and, ultimately, clinical research in optimising treatment regimes.

Incidence of SARS-CoV-2 infection in patients with multiple sclerosis who received SARS-CoV-2 vaccines and are under treatment with high-efficacy therapies in Argentina

We aimed to evaluate the incidence of SARS-CoV-2 breakthrough infection of SARS-CoV-2 vaccines in people with MS (PwMS) on high-efficacy disease-modifying therapies (HET) included in the national MS registry in Argentina (RelevarEM).

METHODS

Non-interventional, retrospective cohort study that collected information directly from RelevarEM. Adult PwMS who had been treated for at least 6 months with a HET (ocrelizumab, natalizumab, alemtuzumab, cladribine) who had received at least two doses of SARS-CoV-2 vaccines available in Argentina were included. Full course of vaccination was considered after the second dose of the corresponding vaccines. Cumulative incidence of SARS-CoV-2 infection was reported for the whole cohort by Kaplan-Meier survival curves (which is expressed in percentage) as well as incidence density (which is expressed per 10.000 patients/day with 95% CI).

RESULTS

Two hundred twenty-eight PwMS were included. Most frequent first and second dose received was AstraZeneca vaccine, followed by Sputnik vaccine. Most frequent HETs used in included patients were cladribine in 79 (34.8%). We found an incidence density of breakthrough COVID-19 infection of 3.5 × 10.000 patients/day (95% CI 2.3-6.7) after vaccination in Argentina. We described the incidence rate after vaccination for every HET used, it being significantly higher for ocrelizumab compared with other HETs (p = 0.005). Only five patients presented a relapse during the follow-up period with no differences regarding the pre-vaccination period.

CONCLUSIONS

We found an incidence density of breakthrough COVID-19 infection of 3.5 × 10.000 patients/day (95% CI 2.3-6.7) after vaccination in Argentina.

Pathogen recognition pathway gene variants and inflammasome sensors gene expression in tuberculosis patients under treatment

BACKGROUND

Several epidemiological studies have suggested that genetic variations in encoding pattern recognition receptors (PRRs) genes such as Toll Like Receptors (TLRs) and their signaling products, may influence the susceptibility, severity and outcome of tuberculosis (TB). After sensing a pathogen, the cell responds producing an inflammatory response, to restrain the pathogen's successful course of infection. Herein we assessed single nucleotide polymorphisms (SNP) and gene expression from pathogen recognition and inflammasome pathways in Brazilian TB patients.

METHODS AND RESULTS

For genetic association analysis we included MYD88 and TLR4, PRRs sensing proteins. Allele distribution for MYD88 rs6853 (A > G) and TLR4 rs7873784 (C > G) presented conserved among the tested samples with statistically differential distribution in TB patients versus controls. However, when testing according to sample ethnicity (African or Caucasian-derived individuals) we identified that the rs6853 G/G genotype was associated with a lower susceptibility to TB in Caucasian population. Meanwhile, the rs7873784 G/G genotype was associated with a higher TB susceptibility in Afro-descendant ethnicity individuals. We also aimed to verify MYD88 and the inflammasome genes NLRP1 and NLRC4 expression in order to connect to active TB and/or clinical aspects.

CONCLUSIONS

We identified that inflammasome gene expression in TB patients under treatment display a similar pattern as in healthy controls, indicating that TB treatment impairs NLRP1 inflammasome activation.

Prevalence of atrial fibrillation and reasons for undertreatment with oral anticoagulants

OBJECTIVES

To investigate the prevalence of atrial fibrillation (AF), the proportion of AF patients not receiving oral anticoagulation (OAC) and reasons for abstaining from OAC treatment.

METHODS

A retrospective cross-sectional study of patients aged 18 years or older with an AF diagnosis on June 1st 2020 in Västernorrland County, Sweden. AF diagnosis was retrieved using the ICD10 code I.48, and medical records were reviewed for comorbidities and documented reasons to abstain OAC treatment.

RESULTS

Of 197 274 residents in Västernorrland County, 4.7% (9 304/197 274) had a documented AF diagnosis. Of these, 19% (1 768/9 304) had no OAC treatment, including 4.2% (393/9 304) with no indication, 2.5% (233/9 304) with a questionable and 2.5% (231/9 304) with a documented clear contraindication for OAC. In total 9.8% (911/9 304) were not treated with OAC despite indication and no reasonable documented contraindication, thus 90.8% (8 447/9 304) of all AF-patients were eligible for OAC treatment. Common reasons for abstaining treatment without reasonable contraindication were present sinus rhythm in 13.7% (125/911), perceived not an OAC candidate in 10.6% (97/911) and anemia in the past in 4.3% (39/911).

CONCLUSIONS

In the population of Västernorrland County, a very high AF prevalence of 4.7% was found, of which just over 90% would theoretically benefit from OAC treatment. This is higher than previously reported and stresses the importance of stroke prevention in this large patient group.

[Smoking cessation in smokers under treatment for lung cancer. Current data]

In 2020, lung cancer was the cause of 18 % of all cancer deaths; smoking accounting for around 90 % of all lung cancers. Despite advances in lung cancer treatment, tobacco control measures are the most effective in curbing the lung cancer epidemic. Nevertheless, smoking cessation at all stages of the cancer process is associated with benefits in terms of cure, improved life expectancy and quality of life for patients, reduced medical or surgical complications, and reduced risk of recurrence or occurrence of a second primary cancer. Consequently, smoking cessation is an essential component of lung cancer treatment. All healthcare professionals, particularly those involved in the care of lung cancer patients, must help smokers to quit.

Characterization of Wnt signaling pathway under treatment of Lactobacillus acidophilus postbiotic in colorectal cancer using an integrated in silico and in vitro analysis

Colorectal cancer (CRC) is a prevalent and life-threatening cancer closely associated with the gut microbiota. Probiotics, as a vital microbiota group, interact with the host's colonic epithelia and immune cells by releasing a diverse range of metabolites named postbiotics. The present study examined the effects of postbiotics on CRC's prominent differentially expressed genes (DEGs) using in silico and in vitro analysis. Through single-cell RNA sequencing (scRNA-seq), we identified four DEGs in CRC, including secreted frizzled-related protein 1 (SFRP1), secreted frizzled-related protein 2 (SFRP2), secreted frizzled-related protein 4 (SFRP4), and matrix metallopeptidase 7 (MMP7). Enrichment analysis and ExpiMap, a novel deep learning-based method, determined that these DEGs are involved in the Wnt signaling pathway as a primary cascade in CRC. Also, spatial transcriptome analysis showed specific expression patterns of the SFRP2 gene in fibroblast cell type. The expression of selected DEGs was confirmed on CRC and normal adjacent tissues using Real-Time quantitative PCR (RT-qPCR). Moreover, we examined the effects of postbiotics extracted from Lactobacillus acidophilus (L. acidophilus) on the proliferation, migration, and cell cycle distribution of HT-29 cells using MTT, scratch, and flow cytometry assays. Our results showed that L. acidophilus postbiotics induce cell cycle arrest at G1 phase and also had anti-proliferative and anti-migration effects on HT-29 cells, while it did not exert anti-proliferative activity on control fibroblasts. Finally, we revealed that treating HT-29 cells with postbiotics can affect the expression of selected DEGs. We suggested that L. acidophilus postbiotics have therapeutic potential in CRC by modulating key genes in the Wnt pathway.

Effects of the lockdown due to the COVID-19 pandemic on alcohol consumption in patients under treatment in an alcohol relapse prevention programme

During the COVID-19 pandemic, several exceptional measures were put in place in order to avoid virus propagation, such as lockdown and the discontinuation of usual health care assistance services. It was considered that these changes might be associated with an increase in alcohol consumption and a higher risk of relapse for patients under treatment. The aim of this study was to assess changes in alcohol consumption during the lockdown period (between March and May, 2020) in patients following treatment under the Alcohol Use Disorders Programme at the "Hospital 12 de Octubre" in Madrid. A total of 311 patients were assessed through interviews carried out by telephone in accordance with usual clinical practice during that period. 76% of the total number of patients did not experience changes in their alcohol consumption, 9.2% stopped drinking and some experienced severe withdrawal syndrome, while 7.5% relapsed. The risk factors found for worsening the prognosis of the patients were: being female, drinking alcohol alone or at home, binge drinking, concomitant substance misuse and failure to attend therapy groups or self-help groups online during the lockdown. 31.6% of the sample described psychopathological symptoms due to the lockdown, especially those who already had psychiatric comorbidities. For this reason, we can conclude that during the lockdown as a result of the pandemic, most of our alcohol dependent patients did not modify their drinking patterns, but specific factors enabled us to identify a more vulnerable subgroup.