Trajectory of functional outcome and health status after moderate-to-major trauma in Hong Kong: A prospective 5 year cohort study

BACKGROUND

Trauma care systems in Asia have been developing in recent years, but there has been little long-term outcome data from injured survivors. This study aims to evaluate the trajectory of functional outcome and health status up to five years after moderate to major trauma in Hong Kong.

METHODS

We report the five year follow up results of a multicentre, prospective cohort from the trauma registries of three regional trauma centres in Hong Kong. The original cohort recruited 400 adult trauma patients with ISS ≥ 9. Telephone follow up was conducted longitudinally at seven time points, and the extended Glasgow Outcome Scale (GOSE) and Short-Form 36 (SF36) were tracked.

RESULTS

119 out of 309 surviving patients (39%) completed follow up after 5 years. The trajectory of GOSE, PCS and MCS showed gradual improvements over the seven time points. 56/119 (47.1%) patients reported a GOSE = 8 (upper good recovery), and the mean PCS and MCS was 47.8 (95% CI 45.8, 49.9) and 55.8 (95% CI 54.1, 57.5) respectively at five years. Univariate logistic regression showed change in PCS - baseline to 1 year and 1 year to 2 years, and change in MCS - baseline to 1 year were associated with GOSE = 8 at 5 years. Linear mixed effects model showed differences in PCS and MCS were greatest between 1-month and 6-month follow up.

CONCLUSIONS

After injury, the most rapid improvement in PCS and MCS occurred in the first six to 12 months, but further recovery was still evident for MCS in patients aged under 65 years for up to five years.

Uptake of breast screening and associated factors among Hong Kong women aged ≥50 years: a population-based survey

OBJECTIVE

To examine the uptake of breast screening and its associated factors among Hong Kong Chinese women aged ≥50 years.

STUDY DESIGN

Cross-sectional population-based survey.

METHODS

A sample of Hong Kong Chinese women was recruited through telephone random-digit dialling. The survey consisted of six sections: perceived health status, use of complementary medicine, uptake of breast screening, perceived susceptibility to cancer, family history of cancer and demographic data. The factors associated with uptake of breast screening were analysed using logistic regression analysis.

RESULTS

In total, 1002 women completed the (anonymous) telephone survey. The mean age was 63.5 (standard deviation 10.6) years. The uptake rate of breast screening among Hong Kong Chinese women aged ≥50 years was 34%. The primary reasons for undertaking breast screening were as part of a regular medical check-up (74%), prompted by local signs and symptoms (11%) and a physician's recommendation (7%). Higher educational level, married or cohabiting, family history of cancer, frequent use of complementary therapies, regular visits to a doctor or Chinese herbalist, and the recommendation of a health professional were all independently and significantly associated with increased odds of having had a mammogram.

CONCLUSIONS

This study provides community-based evidence of the need for public health policy to promote broader use of mammography services among this target population, with emphasis on the active involvement of health care professionals, through the development and implementation of appropriate evidence-based and resource-sensitive strategies.

Differences in the compliance with hospital infection control practices during the 2009 influenza H1N1 pandemic in three countries

BACKGROUND

In December 2009, the World Health Organization (WHO) issued updated guidelines on the prevention of H1N1 influenza virus in healthcare settings. In 2010, the WHO pandemic influenza alert level was still at phase 6.

AIM

To study the practice of infection control measures during the 2009 influenza H1N1 pandemic among healthcare workers (HCWs) in three countries.

METHODS

A standardized, self-administered anonymous questionnaire survey was conducted in 2010 among doctors, nurses and allied HCWs in 120 hospital-based clinical departments in Hong Kong, Singapore and the UK. Questions were asked on demographics; previous experience and perceived severity of influenza; infection control practices; uptake of seasonal influenza vaccination and H1N1 vaccination. Multiple logistic regression was used to test the independent association with different factors.

FINDINGS

A total of 2100 HCWs in the three countries participated. They reported high compliance (>80%) with infection control procedures regarded as standard for droplet-transmitted infections including wearing and changing gloves, and washing hands before and after patient contact. However, the reported use of masks with indirect or direct patient contact (surgical or N95 as required by their hospital) varied considerably (96.4% and 70.4% for Hong Kong; 82.3% and 87.7% for Singapore; 25.3% and 62.0% for the UK). Reported compliance was associated with job title, number of patient contacts and perceived severity of pandemics. There was no association between the uptake for seasonal or 2009 H1N1 vaccines and compliance.

CONCLUSIONS

Compliance with infection control measures for pandemic influenza appears to vary widely depending on the setting.

Cancer aggregation and complex segregation analysis of families with female non-smoking lung cancer probands in Taiwan

Previous studies have found that having a first-degree blood relative with lung cancer was a possible predictor of lung cancer risk, but some studies have indicated that the association is non-significant or only significant for a subset of the studied population. To determine the familial aggregation and whether there is any evidence for a gene controlling the susceptibility to developing lung cancer in female non-smokers, multiple logistic regression methods for estimating covariate effects and maximum likelihood segregation analyses were performed using data from 216 female non-smoking lung cancer probands (2328 individuals) in a population-based case-control study. Having a family history of lung cancer was found to be a significant predictor of lung cancer for non-smoking females (Adjusted Odds Ratio (OR)=5.7, 95% Confidence Interval (CI)=1.9-16.9). Having a female relative with lung cancer (adjusted OR=14.4, 95% CI=2.7-75.5) was more strongly associated with the lung cancer risk than was having a male relative with lung cancer. This association was stronger for probands aged less than 60 years at onset (adjusted OR=11.2, 95% CI=2.2-56.9). All of the Mendelian models fitted the data significantly better than the sporadic (no major type) model or the environmental model (P<0.00l). The Mendelian codominant models provided the best fit of the data for the early onset probands and showed a stronger effect for a major susceptibility locus for non-smoking lung cancer probands. The results of this study provide evidence that a rare autosomal codominant gene may influence the risk lung cancer in non-smoker and is responsible for the familial aggregation observed in non-smoking lung cancer patients.

Evidence for an association between cutaneous melanoma and non-Hodgkin lymphoma

BACKGROUND

Over the past 2 decades both cutaneous melanoma (CM) and non-Hodgkin lymphoma (NHL) incidence rates have increased substantially. One approach to better understanding the etiologic basis for these increases is to examine the risk of NHL in CM survivors and the risk of CM in NHL survivors.

METHODS

To explore the possible association between CM and NHL, the authors followed cohorts of CM and NHL patients registered through the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 1996 and identified patients who developed CM after NHL and NHL after CM. The number of observed cases then were compared with the number of expected cases to see if CM survivors were at an increased risk of NHL or if NHL survivors were at an increased risk of CM.

RESULTS

Between 1973 and 1996, 54,803 CM patients and 62,597 NHL patients who met the authors' inclusion criteria were identified through SEER. The authors found statistically significant elevated risks of NHL among CM survivors (standardized incidence ratio [SIR], 1.42; 95% confidence interval [CI], 1.23-1.63) and CM among NHL survivors (SIR, 1.75; 95% CI, 1.48-2.07).

CONCLUSIONS

These results support an association between CM and NHL. Although detection bias and posttherapy effects may explain part of this association, shared genetic or etiologic factors, such as sunlight exposure, also may play a role.

A proportional hazards model for multivariate interval-censored failure time data

This paper focuses on the methodology developed for analyzing a multivariate interval-censored data set from an AIDS observational study. A purpose of the study was to determine the natural history of the opportunistic infection cytomeglovirus (CMV) in an HIV-infected individual. For this observational study, laboratory tests were performed at scheduled clinic visits to test for the presence of the CMV virus in the blood and in the urine (called CMV shedding in the blood and urine). The study investigators were interested in determining whether the stage of HIV disease at study entry was predictive of an increased risk for CMV shedding in either the blood or the urine. If all patients had made each clinic visit, the data would be multivariate grouped failure time data and published methods could be used. However, many patients missed several visits, and when they returned, their lab tests indicated a change in their blood and/or urine CMV shedding status, resulting in interval-censored failure time data. This paper outlines a method for applying the proportional hazards model to the analysis of multivariate interval-censored failure time data from a study of CMV in HIV-infected patients.

Thymosin beta-15 predicts for distant failure in patients with clinically localized prostate cancer-results from a pilot study

OBJECTIVES

To report the results of a pilot study on the prognostic value of a newly identified actin-binding protein, thymosin beta-15 (Tbeta15), in predicting prostate-specific antigen (PSA) and bone failure in patients with Gleason 6/10 clinically localized prostate cancer.

METHODS

Thirty-two patients (median age 70 years) with clinically localized, moderately differentiated (Gleason 6/10) prostate cancer treated by external beam radiotherapy alone (68.4 Gy) with available paraffin blocks at the Massachusetts General Hospital were evaluated for this pilot study. All patients had clinical Stage M0 disease at initial presentation, which was documented by bone scan (T1c-4,NX). Their corresponding biopsy specimens were stained immunohistochemically for Tbeta15, which was then correlated with the clinical outcome in a blinded manner. The median follow-up was 6 years (range 1 to 19) for all of the patients.

RESULTS

The outcomes of the 32 patients can be grouped into three categories: patients with no evidence of disease (n = 11), patients with PSA failure without documented bone failure (n = 11), and patients with PSA failure and documented bone failure (n = 10). Tbeta15 staining intensity strongly correlated with clinical outcome. Of those patients whose specimens stained 3+ (strongest staining), 62% developed bone failure compared with 13% of those patients whose specimens stained 1+ (weakest staining) (P = 0.01). The 5-year freedom from PSA failure was only 25% for those patients with 3+ staining compared with 83% for those with 1+ staining (P = 0.02).

CONCLUSIONS

The results of this pilot study have demonstrated that Tbeta15 staining intensity may be a potentially important marker to identify high-risk patients with moderately differentiated, clinically localized prostate cancer.

Applying the Cox proportional hazards model for analysis of latency data with interval censoring

The latency time of an infectious disease is defined as the time from infection to disease onset. This paper applies the proportional hazards model to estimate the effect of covariates on latency when the time of disease onset is exact or right-censored but the time of infection is interval-censored. We use a Monte Carlo EM algorithm to estimate parameters of the joint distribution of infection times and latency times. At each EM iteration, exact infection times are multiply imputed from the density determined by the parameters of the infection and latency time distributions. The methodology is tested using a simulation study and is applied to data from a cohort of haemophiliacs with HIV disease.

Applying the Cox proportional hazards model when the change time of a binary time-varying covariate is interval censored

This paper develops methodology for estimation of the effect of a binary time-varying covariate on failure times when the change time of the covariate is interval censored. The motivating example is a study of cytomegalovirus (CMV) disease in patients with human immunodeficiency virus (HIV) disease. We are interested in determining whether CMV shedding predicts an increased hazard for developing active CMV disease. Since a clinical screening test is needed to detect CMV shedding, the time that shedding begins is only known to lie in an interval bounded by the patient's last negative and first positive tests. In a Cox proportional hazards model with a time-varying covariate for CMV shedding, the partial likelihood depends on the covariate status of every individual in the risk set at each failure time. Due to interval censoring, this is not always known. To solve this problem, we use a Monte Carlo EM algorithm with a Gibbs sampler embedded in the E-step. We generate multiple completed data sets by drawing imputed exact shedding times based on the joint likelihood of the shedding times and event times under the Cox model. The method is evaluated using a simulation study and is applied to the data set described above.

An ergonomic analysis of premixing and compounding processes in an animal health plant

This study is based on an ergonomic job analysis designed to develop a hazard prevention program for the premixing and compounding processes in animal health products plants. Animal health products plants are "pharmaceutical facilities" for livestock or domestic animals. A hazardous aerosol (highly concentrated antibiotics, anthelmintics, mineral oil, and animal hormones) is generated in the premixing or compounding processes. The animal health premixing jobs are heavy-duty jobs and have high potential for chemical exposure, heat stress, and ergonomic hazards. Ergonomic job analysis was used to recognize, identify, and evaluate actuarial and potential risks of injures or irritations. Chemical hazards and eight ergonomic factors were discussed: (1) forceful exertions, (2) awkward postures, (3) localized contract stresses, (4) vibration, (5) noise, (6) temperature extremes, (7) repetitive activities, and (8) prolonged activities. The results show that (1) current practices do not violate occupational safety and health regulations or recommended guidelines, but that hazards should be identified to protect worker health and safety; (2) for chemical hazards prevention, operators wear whole-body protection equipment, which also causes heat stress and increases the noise level in the work zone; and (3) the loading weight of the bags used needs to be reduced.

A Markov chain Monte Carlo EM algorithm for analyzing interval-censored data under the Cox proportional hazards model

This paper proposes a Monte Carlo EM (MCEM) algorithm for fitting the proportional hazards model for interval-censored failure-time data. The algorithm generates orderings of the failures from their probability distribution under the model. We maximize the average of the log-likelihoods from these completed data sets to obtain updated parameter estimates. As with the standard Cox model, this algorithm does not require the estimation of the baseline hazard function. The performance of the algorithm is evaluated using simulations, and the method is applied to data from AIDS and cancer studies. Our results indicate that our method produced more precise and unbiased estimates than methods of right and midpoint imputation.