Hypertension artérielle pulmonaire des connectivites

Predicting clinical events using Bayesian multivariate linear mixed models with application to scleroderma

BACKGROUND

Scleroderma is a serious chronic autoimmune disease in which a patient's disease state manifests in several irregularly spaced longitudinal measures of lung, heart, skin, and other organ systems. Threshold crossings of pulmonary and cardiac measures indicate potentially life-threatening key clinical events including interstitial lung disease (ILD), cardiomyopathy, and pulmonary hypertension (PH). The statistical challenge is to accurately and precisely predict these events by using all of the clinical history for the patient at hand and for a reference population of patients.

METHODS

We use a Bayesian mixed model approach to simultaneously characterize each individual's future trajectories for several biomarkers. We estimate this model using a large population of patients from the Johns Hopkins Scleroderma Center Research Registry. The joint probabilities of critical lung and heart events are then calculated as a byproduct of the mixed model.

RESULTS

The performance of this approach is substantially better than standard, more common alternatives. In order to predict an individual's risks in a clinical setting, we also develop a cross-validated, sequential prediction (CVSP) algorithm. As additional data are observed during a patient's visit, the algorithm sequentially produces updated predictions for the future longitudinal trajectories and for ILD, cardiomyopathy, and PH. The updated prediction distributions with little additional computing, for example within an electronic health record (EHR).

CONCLUSIONS

This method that generates real-time personalized risk estimates has been implemented within the electronic health record system for clinical testing. To our knowledge, this work represents the first approach to compute personalized risk estimates for multiple scleroderma complications.

[Atypical arthritis of the hands : Collagenosis-part 2]

BACKGROUND

Progressive systemic scleroderma (PSS) and mixed connective tissue disease (MCTD) represent vasculitic autoimmune diseases from the group of collagenoses with manifestations in various organ systems such as the skin, the internal organs and the joints.

OBJECTIVE

To present the atypical arthritis patterns of the hands in PSS and MCTD that differ from those in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) in the context of clinical and serologic findings and in consideration of the classification of PSS and MCTD.

MATERIALS AND METHODS

Narrative review based on the current literature on the subject from the radiological and rheumatological point of view.

RESULTS

In PSS, combinations of acral soft tissue atrophy, nonreactive acro-osteolysis, and interstitial calcifications can be visualized by projection radiography, which in the final stage can lead to a scleroderma claw hand. Digital pharmacoangiography of the hands can be used to reliably diagnose manifest vascular occlusions of the digital arteries. MCTD is characterized by various overlapping symptoms of at least two systemic autoimmune diseases and most frequently presents in the hand with symmetrical involvement of the PIP (proximal interphalangeal), MCP (metacarpophalangeal) and wrist joints with the manifestation of so-called "puffy fingers".

CONCLUSIONS

The presented morphological atypical arthritis patterns of the hands in PSS and MCTD differ considerably from the typical patterns in the hands in RA and PsA. MRI is useful to diagnose early stages and pharmacoangiography can be used to differentiate between temporary and manifest digital vascular occlusions.

Prevalence and etiologies of pulmonary hypertension in Africa: a systematic review and meta-analysis

BACKGROUND

Despite the recent increasing worldwide attention towards pulmonary hypertension (PH), its epidemiology remains poorly described in Africa. Accordingly, we performed a systematic review and meta-analysis of PH prevalence, incidence and etiologies in Africa.

METHODS

We searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus. Published observational studies until September 20, 2017, including adult participants residing in Africa were considered. Two review authors independently selected studies, assessed included studies for methodological quality, and extracted data. A random-effects model was used for meta-analysis. Heterogeneity was evaluated by the χ 2 test on Cochrane's Q statistic which is quantified by I2 values. Using Newcastle-Ottawa Scale, we considered a score of 0-4, 5-7, and 8-10 as indicative of high, moderate, and low risk of bias in included studies, respectively.

RESULTS

Of 1611 entries, 25 studies were retained. Twelve (48%), seven (28%), and six (24%) papers had respectively a low, moderate and high risk of bias. The prevalence of PH widely varied across different populations: 9.8% (95% confidence interval: 3.2-19.3; I2 = 99.4%; 6 studies) in 11,163 people presenting with cardiac complaints; 10.6% (4.3-19.1; I2 = 90.3%; 4 studies) in 937 HIV-infected people; 32.9% (17.6-50.4; I2 = 97.2%; 3 studies) in 2077 patients with heart failure; 23.2% (15.2-32.2; I2 = 59.4%; 3 studies) in 248 patients on hemodialysis; 12.9% (11.8-14.0; I2 = 79.7%; 2 studies) in 3750 patients with rheumatic heart disease; 36.9% (29.7-44.3; I2 = 79.7; 2 studies) in 79 patients with sickle cell disease; 62.7% (49.0-74.7; 1 study) in 51 patients with chronic obstructive pulmonary disease; 25.4% (16.3-37.3; 1 study) in 63 patients with systemic lupus erythematous; 68.7% (62.8-74.1; 1 study) in 259 patients with cardiac surgery; and 7.4% (4.6-11.9; 1 study) in 202 patients with systemic sclerosis. No study reported PH incidence. From one international study (n = 209), PH etiologies were: left heart disease (68.9%), pulmonary arterial hypertension (15.8%), lung disease and/or hypoxia (12.0%), chronic thromboembolic PH (1.9%) and unclear/multifactorial PH (15.8%).

CONCLUSION

The prevalence of PH is relatively high in some populations in Africa, perhaps mainly driven by left heart diseases, highlighting the need for context-specific interventions.

Outcome of Patients with Systemic Sclerosis in the Intensive Care Unit

Objective.

Patients with systemic sclerosis (SSc) are prone to disease-specific or treatment-related life-threatening complications that may warrant intensive care unit (ICU) admission. We assessed the characteristics and current outcome of patients with SSc admitted to the ICU.

Methods.

We performed a single-center retrospective study over 6 years (November 2006–December 2012). All patients with SSc admitted to the ICU were enrolled. Short-term (in-ICU and in-hospital) and longterm (6-mo and 1-yr) mortality rates were studied, and the prognostic factors were analyzed.

Results.

Forty-one patients with a median age of 50 years [interquartile range (IQR) 40–65] were included. Twenty-nine patients (72.5%) displayed diffuse cutaneous SSc. The time from diagnosis to ICU admission was 78 months (IQR 34–128). Twenty-eight patients (71.7%) previously had pulmonary fibrosis, and 12 (31.5%) had pulmonary hypertension. The main reason for ICU admission was acute respiratory failure in 27 patients (65.8%). Noninvasive ventilation was first attempted in 13 patients (31.7%) and was successful in 8 of them, whereas others required endotracheal intubation within 24 h. Altogether, 13 patients (31.7%) required endotracheal intubation and mechanical ventilation. The overall in-ICU, in-hospital, 6-month, and 1-year mortality rates were 31.8%, 39.0%, 46.4%, and 61.0%, respectively. Invasive mechanical ventilation was the worst prognostic factor, associated with an in-hospital mortality rate of 84.6%.

Conclusion.

This study provides reliable prognostic data in patients with SSc who required ICU admission. The devastating outcome of invasive mechanical ventilation in patients with SSc requires a reappraisal of indications for ICU admission and early identification of patients likely to benefit from noninvasive ventilation.