Logistische Regression

Antineutrophil cytoplasmic antibodies in bile are associated with disease activity in primary sclerosing cholangitis

OBJECTIVE. Primary sclerosing cholangitis (PSC) is an autoimmune cholestatic liver disease of unknown etiology. The role of antineutrophil cytoplasmic antibodies (ANCAs) in the serum of patients with PSC remains unclear. We hypothesized that ANCA may be detectable in bile, potentially providing diagnostic and prognostic information. METHODS. Serum and bile were prospectively collected during endoscopic retrograde cholangiography (ERC) in 72 patients with PSC and other non-PSC obstructive biliary diseases. ANCA measurements were performed by indirect immunofluorescence (IIF). RESULTS. Immunoglobulin G (IgG) ANCA was detected significantly more often in the bile of PSC patients (15/39; 38%) than without (2/33; 6%) (p = 0.001). IgG ANCA in bile was associated with a ten times higher risk of PSC (p = 0.005). In addition, IgG ANCA positivity in bile was associated with the presence of dominant strictures (p = 0.03), cholangiographic severity (p = 0.004), number of ERC (p = 0.01) and interventions performed (p = 0.03). However, IgG ANCA in bile did not correlate with transplantation, cholangiocarcinoma or death. No association was observed between ANCA positivity in sera and ANA and ASCA positivity in sera or bile with the above-mentioned clinical features. CONCLUSIONS. The presence of ANCA in the bile of patients with PSC is a novel finding and highly suggestive of PSC. Biliary IgG ANCA correlates with the severity of bile duct strictures and the ensuing number of ERCs and interventions. Therefore, a positive ANCA status in bile may serve as a diagnostic and prognostic marker of the disease progression and biliary complications.

Patients feeling severely affected by multiple sclerosis: how do patients want to communicate about end-of-life issues?

OBJECTIVE

Investigate multiple sclerosis patients' desire to communicate with their physicians about their disease progression and end-of-life issues.

METHODS

Persons meeting the inclusion criteria of feeling severely affected by MS were invited via the German MS society to complete a needs questionnaire. Replies to questions on physician empathy and wishes about communication regarding disease progression and death and dying were quantitatively analyzed. Endpoints (point 1+2/4+5) of 5-point-likert scales are summarized under results.

RESULTS

573 of 867 questionnaires meeting our criteria were analyzed. In response to a general question 64% (n = 358) indicated a wish for disease progression and death and dying to be addressed by their doctor. A majority (76%, n = 427) considered it important that progression of their disease be discussed, while 44% (n = 246) regard addressing death and dying as unimportant. No objective disease criteria could be identified to explain the wish for communicating end-of-life issues. Doctors who were retrospectively viewed as avoiding raising critical aspects of the illness were perceived as less empathetic (p < 0.001).

CONCLUSION

People with MS have a desire to talk about progression of their disease with their doctors.

PRACTICE IMPLICATIONS

Physicians should be empathetic in raising critical aspects of the patients' illness individually.

Data analysis of epidemiological studies: part 11 of a series on evaluation of scientific publications

INTRODUCTION

An important objective of epidemiological research is to identify risk factors for disease. Depending on the particular question being asked, cohort studies, case-control studies, or cross-sectional studies are conducted.

METHODS

Methods of data analysis in different types of epidemiological studies are illustrated through examples with fictive data. Important measures of frequency and effect will be introduced. Different regression models will be presented as examples of complex analytical methods.

RESULTS

Important frequency measures in cohort studies are incidence and mortality. Important effect measures such as the relative risk (RR), hazard ratio (HR), standardized incidence ratio (SIR), standardized mortality ratio (SMR), and odds ratio (OR) can also be calculated. In case-control or cross-sectional studies, the OR can be calculated as an effect measure. In cross-sectional studies, prevalence is the most important frequency measure. The interpretation of different frequency measures and effect measures will be discussed.

CONCLUSION

The measures to be calculated and the analyses to be performed in an epidemiological study depend on the research questions being asked, the study type, and the available data.