Multi-state model for predicting ocular progression in acute Stevens-Johnson syndrome/toxic epidermal necrolysis

Improvement of the Ocular Prognosis of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A National Survey in Japan

PURPOSE

To investigate the incidence and prognostic factors of ocular sequelae in Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) cases arising between 2016 and 2018 in Japan, and compare the findings with those presented in the previous 2005-2007 survey.

DESIGN

Retrospective, national trend survey.

METHODS

Dermatologic case report forms (CRFs) (d-CRFs) were sent to 257 institutions that treated at least 1 SJS/TEN case, and 508 CRFs were collected from 160 institutions. Ophthalmologic CRFs (o-CRFs) regarding patient demographic data, onset date, ocular findings (first appearance, day of worst severity, and final follow-up), topical treatment (betamethasone), outcome (survival or death), and ocular sequelae (visual disturbance, eye dryness) were sent to the ophthalmologists in those 160 institutions. The results of this survey were then compared with that of the previous 2005-2007 survey.

RESULTS

A total of 240 cases (SJS/TEN: 132/108) were included. The incidence of ocular sequelae incidence was 14.0%, a significant decrease from the 39.2% in the previous survey (SJS/TEN: 87/48). In 197 (82.1%) of the cases, systemic treatment was initiated within 3 days after admission, an increase compared to the previous survey (ie, treatment initiated in 82 [60.7%] of 135 cases). Of the 85 cases with an Acute Ocular Severity Score of 2 and 3, 62 (72.9%) received corticosteroid pulse therapy and 73 (85.9%) received 0.1% betamethasone therapy; an increase compared to the 60.0% and 70.8%, respectively, in the previous survey. Ocular-sequelae-associated risk factors included Acute Ocular Severity Score (P < .001) and specific year in the survey (P < .001).

CONCLUSIONS

The ophthalmologic prognosis of SJS/TEN has dramatically improved via early diagnosis, rapid assessment of acute ocular severity, and early treatment.

Using multistate models with clinical trial data for a deeper understanding of complex disease processes

A clinical trial represents a large commitment from all individuals involved and a huge financial obligation given its high cost; therefore, it is wise to make the most of all collected data by learning as much as possible. A multistate model is a generalized framework to describe longitudinal events; multistate hazards models can treat multiple intermediate/final clinical endpoints as outcomes and estimate the impact of covariates simultaneously. Proportional hazards models are fitted (one per transition), which can be used to calculate the absolute risks, that is, the probability of being in a state at a given time, the expected number of visits to a state, and the expected amount of time spent in a state. Three publicly available clinical trial datasets, colon, myeloid, and rhDNase, in the survival package in R were used to showcase the utility of multistate hazards models. In the colon dataset, a very well-known and well-used dataset, we found that the levamisole+fluorouracil treatment extended time in the recurrence-free state more than it extended overall survival, which resulted in less time in the recurrence state, an example of the classic "compression of morbidity." In the myeloid dataset, we found that complete response (CR) is durable, patients who received treatment B have longer sojourn time in CR than patients who received treatment A, while the mutation status does not impact the transition rate to CR but is highly influential on the sojourn time in CR. We also found that more patients in treatment A received transplants without CR, and more patients in treatment B received transplants after CR. In addition, the mutation status is highly influential on the CR to transplant transition rate. The observations that we made on these three datasets would not be possible without multistate models. We want to encourage readers to spend more time to look deeper into clinical trial data. It has a lot more to offer than a simple yes/no answer if only we, the statisticians, are willing to look for it.

Calibration plots for multistate risk predictions models

INTRODUCTION

There is currently no guidance on how to assess the calibration of multistate models used for risk prediction. We introduce several techniques that can be used to produce calibration plots for the transition probabilities of a multistate model, before assessing their performance in the presence of random and independent censoring through a simulation.

METHODS

We studied pseudo-values based on the Aalen-Johansen estimator, binary logistic regression with inverse probability of censoring weights (BLR-IPCW), and multinomial logistic regression with inverse probability of censoring weights (MLR-IPCW). The MLR-IPCW approach results in a calibration scatter plot, providing extra insight about the calibration. We simulated data with varying levels of censoring and evaluated the ability of each method to estimate the calibration curve for a set of predicted transition probabilities. We also developed evaluated the calibration of a model predicting the incidence of cardiovascular disease, type 2 diabetes and chronic kidney disease among a cohort of patients derived from linked primary and secondary healthcare records.

RESULTS

The pseudo-value, BLR-IPCW, and MLR-IPCW approaches give unbiased estimates of the calibration curves under random censoring. These methods remained predominately unbiased in the presence of independent censoring, even if the censoring mechanism was strongly associated with the outcome, with bias concentrated in low-density regions of predicted transition probability.

CONCLUSIONS

We recommend implementing either the pseudo-value or BLR-IPCW approaches to produce a calibration curve, combined with the MLR-IPCW approach to produce a calibration scatter plot. The methods have been incorporated into the "calibmsm" R package available on CRAN.

Topical Betamethasone Treatment of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis with Ocular Involvement in the Acute Phase

PURPOSE

To clarify the importance of administering topical steroids for the treatment of Stevens-Johnson syndrome (SJS) / toxic epidermal necrolysis (TEN) with ocular involvement in the acute phase.

DESIGN

Retrospective case series.

METHODS

Using the medical records of acute SJS/TEN patients treated at the Kyoto Prefectural University of Medicine Hospital, Kyoto, Japan, between July 2006 and July 2017, the ocular findings, topical steroid dosage, systemic steroid dosage, and ocular sequelae were retrospectively examined. The level of cytokines in tear fluid and serum samples was also analyzed.

RESULTS

This study involved 13 cases. In 10 cases in whom the clinical courses were recorded before the start of steroid therapy, the mean acute ocular severity score (AOSS: 3 = very severe; 2 = severe; 1 = mild; 0 = none) was 2.8 ± 0.4 points in the severest phase. The mean systemic steroid dose after steroid pulse therapy was 694 ± 386 mg and the mean topical steroid (0.1% betamethasone eye drop and ointment) dose was 13.4 ± 3.3 times daily in the severest phase. Analysis of cytokine levels of 4 cases showed that a cytokine storm occurred in the tear fluid after the steroid pulse therapy. At final follow-up, 16 eyes of 8 patients had a logMAR visual acuity of ≤0, and no serious ocular sequelae were observed.

CONCLUSIONS

In patients with SJS/TEN, ocular surface inflammation remains strong even after systemic inflammation has improved post steroid pulse therapy, thus suggesting that both systemic and topical steroid therapy should be administered appropriately.

Associations between obesity, diabetes mellitus, and cardiovascular disease with progression states of knee osteoarthritis (KOA)

BACKGROUND

Data on common comorbidities targeting at different progression states of knee osteoarthritis (KOA) in continuous time are limited.

AIMS

To examine the associations between obesity, diabetes mellitus (DM), and cardiovascular disease (CVD) with the progression of KOA.

METHODS

Data were obtained from the Osteoarthritis Initiative for up to 48 months. Progression states of KOA were defined as (1) normal; (2) asymptomatic radiographic KOA (RKOA, Kellgren-Lawrence grade ≥ 2 in at least one knee); (3) only knee symptoms; (4) symptomatic KOA (SxKOA, a combination of RKOA and knee symptoms in the same knee). A multi-state Markov model was used to investigate the associations while accounting for potential confounders.

RESULTS

Participants with obesity had an increased risk of developing RKOA [normal to asymptomatic RKOA, adjusted hazard ratio (aHR) 1.55, 95% confidence interval (95% CI) (1.07, 2.24); only knee symptoms to SxKOA, aHR 2.25, 95% CI (1.60, 3.18)], and an increased risk of developing knee symptoms [normal to only knee symptoms, aHR 1.45, 95% CI (1.15, 1.83); asymptomatic RKOA to SxKOA, aHR 1.33, 95% CI (1.16, 1.52)]. DM was also significantly associated with development of RKOA or knee symptoms [normal to asymptomatic RKOA, aHR 1.92, 95% CI (1.12, 3.30); normal to only knee symptoms, aHR 1.78, 95% CI (1.12, 2.84)]. Knee symptoms were less likely to be relieved among participants with CVD, compared with those without [only knee symptoms to normal, aHR 0.60, 95% CI (0.38, 0.94)].

CONCLUSIONS

Obesity, DM and CVD are associated with an increased risk for SxKOA progression. Common comorbidities should be considered to prevent KOA development.

Disease severity and status in Stevens–Johnson syndrome and toxic epidermal necrolysis: Key knowledge gaps and research needs

Stevens–Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are on a spectrum of cutaneous drug reactions characterized by pan-epidermal necrosis with SJS affecting < 10% of body surface area (BSA), TEN > 30%, and SJS/TEN overlap between 10 and 30%. Severity-of-illness score for toxic epidermal necrolysis (SCORTEN) is a validated tool to predict mortality rates based on age, heart rate, BSA, malignancy and serum urea, bicarbonate, and glucose. Despite improved understanding, SJS/TEN mortality remains constant and therapeutic interventions are not universally accepted for a number of reasons, including rarity of SJS/TEN; inconsistent definition of cases, disease severity, and endpoints in studies; low efficacy of interventions; and variations in treatment protocols. Apart from mortality, none of the other endpoints used to evaluate interventions, including duration of hospitalization, is sufficiently standardized to be reproducible across cases and treatment centers. Some of the gaps in SJS/TEN research can be narrowed through international collaboration to harmonize research endpoints. A case is made for an urgent international collaborative effort to develop consensus on definitions of endpoints such as disease status, progression, cessation, and complete re-epithelialization in interventional studies. The deficiencies of using BSA as the sole determinant of SJS/TEN severity, excluding internal organ involvement and extension of skin necrosis beyond the epidermis, are discussed and the role these factors play on time to healing and mortality beyond the acute stage is highlighted. The potential role of artificial intelligence, biomarkers, and PET/CT scan with radiolabeled glucose as markers of disease status, activity, and therapeutic response is also discussed.