Prevalence and severity of coronary artery disease linked to prognosis in psoriasis and psoriatic arthritis patients: a multi-centre cohort study.

OBJECTIVES: (i) To estimate the prevalence and severity of coronary artery disease and (ii) to assess the risk of cardiovascular events and mortality, in patients with psoriasis and psoriatic arthritis (PsA) in a large-scale cohort of patients referred to coronary computed tomography angiography (CTA). METHODS: This was a cross-sectional study with follow-up of 46,022 patients based on data from a Danish national CTA registry. Exposure was defined as psoriasis or PsA. A group of patients without psoriasis, PsA or any other inflammatory disease was used as reference. Cross-sectional primary outcomes were a coronary artery calcium score (CACS) >0 and CACS ≥400, and secondary outcome was obstructive CAD. At follow-up, the primary outcome was a composite endpoint of cardiovascular events and all-cause mortality. All outcomes were adjusted for traditional cardiovascular risk factors. RESULTS: We identified 1356 psoriasis and 370 PsA patients. The adjusted odds ratio (OR) for psoriasis patients for CACS >0, CACS ≥400 and obstructive CAD was 1.26 (1.10-1.46), 1.25 (1.04-1.50) and 1.14 (0.98-1.33), respectively. For PsA patients, OR for CACS >0 was 1.28 (1.00-1.64). We found a crude hazard ratio (HR) of 1.49 (1.21-1.85) and adjusted HR of 1.14 (0.92-1.41) for the primary outcome in psoriasis patients. CONCLUSIONS: In this population, both psoriasis and PsA were associated with an increased prevalence of coronary calcification. Psoriasis patients also showed an increased prevalence of severe calcification. Psoriasis patients were at increased risk for cardiovascular events and death, however not after adjusting for the effect of other predictors.

Improving efficiency in stereology: a study applying the proportionator and the autodisector on virtual slides.

Cell counting in stereology is time-consuming. The proportionator is a new stereological sampling method combining automatic image analysis and non-uniform sampling. The autodisector on virtual slides combines automatic generation of disector pairs with the use of digital images. The aim of the study was to investigate the time efficiency of the proportionator and the autodisector on virtual slides compared with traditional methods in a practical application, namely the estimation of osteoclast numbers in paws from mice with experimental arthritis and control mice. Tissue slides were scanned in a digital slide scanner and the autodisector was applied on the obtained virtual tissue slides. Every slide was partitioned into fields of view, and cells were counted in all of them. Based on the original exhaustive data set comprising 100% of fields of view and covering the total section area, a proportionator sampling and a systematic, uniform random sampling were simulated. We found that the proportionator was 50% to 90% more time efficient than systematic, uniform random sampling. The time efficiency of the autodisector on virtual slides was 60% to 100% better than the disector on tissue slides. We conclude that both the proportionator and the autodisector on virtual slides may improve efficiency of cell counting in stereology.