Comparative analysis of recurrent events after presentation with an index myocardial infarction or ischaemic stroke.

Aims: Acute myocardial infarction (AMI) and stroke are important causes of mortality and morbidity. Our aims are to determine the comparative epidemiology of AMI and ischaemic stroke; and examine the differences in cardiovascular outcomes or mortality occurring after an AMI or stroke. Methods and results: The Singapore National Registry of Diseases Office collects countrywide data on AMI, stroke, and mortality. Index events of AMI and ischaemic stroke between 2007 and 2012 were identified. Patients were then matched for occurrences of subsequent AMI, stroke, or death within 1-year of the index event. There were 33 222 patients with first-ever AMI and 20 982 with first-ever stroke. AMI patients were significantly more likely to be men (66.3% vs. 56.9%), non-Chinese (32.1% vs. 24.1%), and smokers (43.1% vs. 38.6%), but less likely to have hypertension (65.6% vs. 79%) and hyperlipidaemia (61.1% vs. 65.5%), compared with stroke patients. In total 6.8% of the AMI patients had recurrent AMI, whereas 4.8% of the stroke patients had recurrent stroke within 1 year; 31.7% of the AMI patients died, whereas 17.1% of the ischaemic stroke patients died within 1 year. Older age, Malay ethnicity, and diabetes mellitus were statistically significant risk factors for all-cause mortality and for the composite endpoint of AMI, stroke, and all-cause mortality, at 1 year. Conclusions: Risk profiles of patients with AMI and stroke are significantly different. Patients suffer recurrent events in vascular territories similar to the index event. Age and diabetes mellitus are significant predictors of recurrent vascular events and mortality.

An analysis of sounds for lungs with excessive water.

Excessive lung water occurs when too much water accumulates in the lung, causing breathing difficulty. Current diagnosis methods include X-rays and CT-scans. However, because of their bulk and the need for trained professionals to operate, physicians rely on auscultation for preliminary diagnosis. Recent attempts have been made to automate the auscultation process and some degree of success has been reported. Thus, it would be useful to provide more analysis of such lung sounds. This paper attempts to study the characteristics of breathing sounds from lungs with excessive water and compare them with breathing sounds from healthy lungs. Using a modified empirical mode decomposition to split the signals, the root-mean-squared energy (RMS) and kurtosis were used as characteristics. These characteristics were extracted from the intrinsic mode functions (IMF) and were analyzed. Results showed that certain IMF were effective in characterizing both kinds of sounds due to their small spread in RMS or kurtosis. Results also (using p-values from statistical tests) showed that for certain intrinsic mode functions, lung sounds with excessive lung water exhibit different medians from sounds of healthy lungs. There was strong linear independence between each IMF of the two sounds. Empirical mode decomposition was shown to be able to extract useful information for analyses.

Geographic factors are associated with increased risk for out-of hospital cardiac arrests and provision of bystander cardio-pulmonary resuscitation in Singapore.

BACKGROUND: Bystander Cardio-Pulmonary Resuscitation (BCPR) can improve survival for Out-of-Hospital Cardiac Arrest (OHCA). This study aimed to investigate the geographic variation of BCPR provision and survival to discharge outcomes among residential OHCA cases, evaluate this variation with individual and population characteristics and identify high-risk residential areas with low relative risk (RR) of BCPR and high RR of OHCA at the development guide plan (DGP) census tract levels in Singapore. METHODS: This was a retrospective, secondary analysis of two prospectively-collected registries in Singapore from 2001 to 2011. We used Bayesian conditional autoregressive spatial models to examine predictors at the DGP level and calculate smoothed RR to identify high-risk areas. We used multi-level mixed-effects logistic regression models to examine the independent effects of individual and neighborhood factors. RESULTS: We found a total of 3942 OHCA with a BCPR rate of 20.3% and a survival to discharge rate of 1.9% and 3578 cases eligible for BCPR. After adjusting for age, witnessed status, presumed cardiac etiology and longer response time, the risk of BCPR provision significantly increased by 0.02% for every 1% increase in the proportion of household size 5 and above in the DGP area (odds ratio 1.02, 95%CI=1.002-1.038, p<0.026). We identified 10 high-risk residential areas with low RR of BCPR and high RR of OHCA. CONCLUSION: This study informed that neighborhood household size could have played a significant role in the provision of BCPR and occurrence of high-risk areas. It demonstrates the public health potential of combining geospatial and epidemiological analysis for improving health.

National population based survey on the prevalence of first aid, cardiopulmonary resuscitation and automated external defibrillator skills in Singapore.

AIM: This study aimed to assess knowledge, attitudes and practices among Singapore residents towards life-saving skills and providing emergency assistance in the community using a population representative sample. METHODS: A population based, random sample of 7840 household addresses were selected from a validated national sampling frame. Respondents were interviewed using face-to-face interview method. One adult aged between 18 and 69 years within each household was randomly selected using the "next birthday" method. RESULTS: The response rate achieved was 65.2% with 4192 respondents. The distribution of age, gender and ethnic group were similar to the Singapore resident population for 2009. A high proportion of participants believed that adults should be trained in first aid (89.1%) and cardiopulmonary resuscitation (CPR) (82.6%) while a lower proportion (57.2%) believed this for automated external defibrillator (AED). Proportion who had ever been trained in first aid was 34.3%, CPR was 31.4% and AED was 10.7%. In an emergency, respondents were most willing to use life-saving skills on family members or relatives (87.6%), followed by friends and colleagues (80.7%) and complete strangers (61.3%). Common barriers to applying life-saving skills were lack of knowledge (36%), fear of doing harm (22.1%) and lack of confidence (15.3%). Respondents who were more likely to have current life-saving certification were younger employed Malay male (p<0.05). CONCLUSION: This study found that although a high proportion of respondents believed that adults should be trained in first aid, CPR and AED, the proportion who had ever been trained in these skills are much lower.

Lung water detection using acoustic techniques.

The presence of an excessive amount of water in lung is a sign of pulmonary edema which can be caused by heart failure. The current solutions for lung water detection involve the use of X-ray, CT scan or serum biomarkers, which require bulky and expensive instruments as well as long measurement duration. This paper reports on a study conducted on the use of a different sensing modality to detect the presence of water in lung. The main contributions of the paper are twofold: 1) we propose to employ acoustic (or sound) based techniques for lung water detection. The design is simple and can be implemented on a portable or wearable system; 2) we establish the feasibility of sound-based techniques for lung water detection, by carrying out experimental studies using four feature extraction methods combined with two classification methods. The findings of this study will be beneficial to the design of portable devices for rapid and accurate lung water detection.