RESUMEN
OBJECTIVES: Sarcoidosis is a clinically heterogenous disease. The objective of this study is the identification of clinical phenotypes using cluster analysis. METHODS: A model-based clustering relaying on 19 clinical variables was performed in a retrospective cohort of 342 sarcoidosis patients, diagnosed and followed-up from 1999 to 2019 in a tertiary hospital at Northern Spain. Chi-square test and ANOVA were used to compare categorical and continuous variables among groups. Two-sample t-tests and the partition of Pearson's chi-square statistic were used in pairwise comparisons. The Wasfi severity score was calculated and compared among clusters. RESULTS: Cluster analysis identified five groups: C1 (16.1%), C2 (14.3%), C3 (24.3%), C4 (5.0%), and C5 (40.4%). Lung involvement was predominant, ranging from 55.1% (C2) to 100% (C1 and C4). Extrapulmonary involvement was significantly higher in C2 (96.4%) and C3 (98.0%). A significant lower FEV1 percent predicted was detected in C5 (90.5±21.8) versus C1 (102.0±22.9), C3 (102.3±17.6) and C4 (105.8±20.8). The cluster 5 had a lower FVC percent predicted (96.6±18.9) than others, ranging from 108.1±18.0 (C3) to 111.5±21.7 (C4). The prescription of systemic glucocorticoids and non-corticosteroid immunosuppressants was higher in the clusters 1, 3 and 5. Chronicity rates were higher in C3 (31.3%) and C5 (32.6%) compared to C1 (9.1%) and C4 (0%), as well as the Wasfi severity score values. CONCLUSIONS: Five phenotypes with different clinical and prognostic characteristics are proposed in our study. Cluster analysis can be a useful tool for identifying clinical patterns in a disease as heterogeneous as sarcoidosis and optimising its management.
RESUMEN
In patients with chronic kidney disease (CKD), the main cause of morbidity and mortality is cardiovascular disease (CVD). Both coronary artery calcium scoring by computed tomography (CT) and optical coherence tomography (OCT) are used to identify patients at increased risk for ischemic heart disease, thereby indicating a higher cardiovascular risk profile. Our study aimed to investigate the utility of these techniques in the CKD population. In patients with CKD, OCT was used to measure the choroidal thickness (CHT) and the thickness of the peripapillary retinal nerve fiber layer (pRNFL). A total of 127 patients were included, including 70 men (55%) with an estimated glomerular filtration rate (eGFR) of 39 ± 30 mL/min/1.73 m2. Lower pRNFL thickness was found to be related to high-sensitivity troponin I (r = -0.362, p < 0.001) and total coronary calcification (r = -0.194, p = 0.032). In a multivariate analysis, pRNFL measurements remained associated with age (ß = -0.189; -0.739--0.027; p = 0.035) and high-sensitivity troponin I (ß = -0.301; -0.259--0.071; p < 0.001). Severe coronary calcification (Agatston score ≥ 400 HU) was related to a worse eGFR (p = 0.008), a higher grade of CKD (p = 0.036), and a thinner pRNFL (p = 0.011). The ROC curve confirmed that the pRNFL measurement could determine the patients with an Agatston score of ≥400 HU (AUC 0.638; 95% CI 0.525-0.750; p = 0.015). Our study concludes that measurement of pRNFL thickness using OCT is related to the markers associated with ischemic heart disease, such as coronary calcification and high-sensitivity troponin I, in the CKD population.