Atrial fibrillation and survival on a medical intensive care unit

BACKGROUND

Atrial fibrillation (AF) is common among patients in the intensive care unit (ICU) and can be triggered by severe illness or preexisting conditions. It is debated if AF is an independent predictor of poor outcome.

METHODS

Data derives from a single center retrospective registry including all patients with a stay on the medical ICU for >24 h. The primary endpoint was ICU survival. Secondary endpoints included receiving mechanical support (renal, respiratory or circulatory), hemodynamic parameters during AF, rate and rhythm control strategies, anticoagulation, and documentation.

RESULTS

A total of 616 patients (male gender 62.3%, median age 75 years) were included in our analysis. New-onset AF was diagnosed in 87 patients (14.1%), 136 (22.1%) presented with preexisting AF, and 393 (63.8%) did not develop AF. Initial episodes of new-onset AF exhibited higher hemodynamic instability than episodes in preexisting cases, with elevated heart rates and increased catecholamine doses (both p < 0.001). ICU survival in new-onset AF was 80.5% (70/87) compared to 92.4% (363/393) in patients without AF (OR 0.340, CI 0.182-0.658, p < 0.001). Likewise, ICU survival in preexisting AF was 86.8% (118/136) was significantly lower compared to no AF (OR 0.542, CI 0.290-0.986, p = 0.050*). Independent predictors of ICU survival for patients were atrial fibrillation (p = 0.016), resuscitation before or during ICU stay (p < 0.001), and receiving acute dialysis on ICU (p = 0.002).

CONCLUSIONS

ICU survival is noticeably lower in patients with new-onset or preexisting atrial fibrillation compared to those without. Patients who develop new-onset AF during their ICU stay warrant special attention for both short-term and long-term care strategies.

Population-Based Differences in Cancer Incidence between Immigrants and Non-Immigrants in Canada from 1992-2015

PURPOSE/OBJECTIVE(S)

The purpose of this study was to investigate if there are differences in cancer incidence between immigrants and non-immigrants in Canada. We hypothesized that immigrants have lower cancer incidence compared to non-immigrants.

MATERIALS/METHODS

In this retrospective study, a linked-database approach was employed using Statistics Canada data. The Canadian Cancer Registry and Canadian Vital Statistics Database were linked with the 1991 Census cohort and the cohort was followed from 1992-2015 for cancer incidence. Excluded persons included Census non-respondents, institutional residents, those living on reserves and those less than 25 years of age. Sampling and bootstrap weights were used to ensure the sample represented the Canadian population and for statistical analyses. Total unweighted and weighted sample was 2,585,160 and 17,002,560, respectively which provided adequate power to answer the research question. Multivariate logistic regression and cox regression models included age, sex, household income, marital status, highest degree of education, knowledge of Canada's official languages (English or French), immigrant status and region of birth. Subcategories of immigrants were created based on time spent in Canada (0-4, 5-9, 10-19, 20+ years).

RESULTS

Raw data showed that 16.8% of immigrants and 15.9% of non-immigrants had cancer. After adjusting, logistic regression analyses showed that immigrants had lower odds of any cancer diagnoses in comparison with non-immigrants (OR = 0.92, 95% CI [0.92,0.93], p<.001), as well as lung (OR = 0.74, 95% CI [0.72-0.75], p<.001); breast (OR = 0.96, 95% CI [0.94-0.98], p = .001); colorectal (OR = 0.93, 95% CI [0.91-0.95], p<.001) and head and neck cancer (OR = 0.85, 95% CI [0.81-0.90], p<.001). However, immigrants had higher odds of stomach cancer and non-cervix gynecological cancers (OR = 1.39, 95% CI [1.32-1.46]; OR = 1.06, 95% CI [1.02-1.10]), respectively. Hazard ratios were lower for immigrants in comparison to the Canadian-born but increased based on time spent in Canada (0-4 years: 0.77, 95% CI [0.71-0.84], p<.001; 5-9 years: 0.82, 95% CI [0.75-0.89], p<.001; 10-19 years: 0.90, 95% CI [0.82-0.98], p = .011).

CONCLUSION

This study demonstrates a significant difference in cancer incidence between immigrants and non-immigrants. These results support current research in the observation of a 'healthy immigrant effect' (HIE) which convey that immigrants have better health outcomes than their native-born counterparts, with the effect decreasing over time spent in the host country. Since we controlled for demographic and socio-economic factors, we propose other factors to be contributing to the HIE such as individual-level health behaviors including smoking, diet and access to screening services. While it points to a HIE, we propose this phenomenon to be more complex due to the possibility of under-reporting of cases or differences in health behaviors, warranting further studies in this area.