Relationship between outcome of written and clinical parts in internal medicine board certifying examination.

Objective: To assess the correlation between written and clinical scores of the Thai Board of Internal Medicine certification examination in different academic years. Methods: Data from 585 internal medicine residents who passed both written and clinical parts of the board certifying examination in the first attempt during the academic year 2005-2007 were collected. Correlation between scores from both parts in each year were then examined. Results: Modest positive linear correlation was found between the written and clinical examination scores in overall (r = 0.57, 0.55, and 0.38, p <0.001 in 2005-2007 respectively). When considered for the subpart of clinical examination scores, the correlation with the section of laboratory interpretation was highest (r = 0.52, 0.54, and 0.33, p <0.001 in 2005-2007 respectively). Conclusion: The outcome of written and clinical parts of certification examination for Thai Board of Internal Medicine had a modest relationship.

Comparison of clinical and polysomnographic characteristics of non-obese and obese patients with obstructive sleep apnea.

OBJECTIVE: To compare the clinical features, anthropometric indices, and polysomnographic data between different body mass index (BMI) subgroups of obstructive sleep apnea (OSA) patients. MATERIAL AND METHOD: The authors reviewed the data from OSA patients in Siriraj Sleep Clinic from April 2005 to September 2006. Objective measurement for sleepiness (Epworth Sleepiness Scale, ESS), anthropometric measurements [body mass index (BMI), neck circumference, thyromental distance, Mallampati S score, and occlusion pattern] and polysomnographic recordings [apnea/hypopnea index (AHI) during REM and NREM periods, respiratory arousal index, periodic leg movement index, minimal oxygen saturation, total sleep time with oxygen saturation <90%, and desaturation index] were collected. The patients were stratified into the non-obese group and obese group if their BMI was <27 or > or =27 kg/m2 respectively. RESULTS: Of the total 158 patients, 71 were non-obese and 87 were obese, no difference in mean age and sex was observed, but more patients with hypertension and coronary artery disease were noted in the obese group. Mean ESS was not different between the 2 groups. In anthropometric measurements, the obese group had statistically significant large neck circumference (41.6 +/- 3.5 cm vs. 37.0 +/- 2.9 cm, p<0.001), but the nonobese group had a shorter thyromental distance (56.4 +/- 11.7 mm vs. 61.4 +/- 11.2 mm, p=0.006), with no significant difference in Mallampatis score and occlusion pattern. In polysomnographic data, the obese group had statistical significantly more severity of various indices except for AHI during the REM period and the periodic limb movement index. CONCLUSION: Non-obese obstructive sleep apnea patients have more bony structural change than the obese ones as demonstrated by shorter thyromental distance. But degree of abnormalities during sleep was less severe in nearly all aspects.

Recovery of heart rate variability in patients with moderate to severe obstructive sleep apnea after 6-month continuous positive airway pressure treatment.

OBJECTIVE: To evaluate the effect of long-term treatment with continuous positive airway pressure (CPAP) on the heart rate variability (HRV) of obstructive sleep apnea (OSA) patients. MATERIAL AND METHOD: Patients with moderate to severe OSA who had never used CPAP treatment were enrolled. Short recording HRV analysis was performed at baseline then at one, three, and six months after CPAP treatment. The measurement included low frequency HRV (LF), high frequency HRV (HF), low frequency to high frequency ratio (LHR), and standard deviation of R-R intervals (SDNN). All domains were measured both during spontaneous and deep breathing. RESULTS: There were 10 patients in the present study, all were men with the mean age of 45 years, mean body mass index 29.3 kg/m2, mean apnea-hypopnea index 60.9 events/hour, and mean average CPAP usage 4.8 hours/night. The HRV showed no significant change after one and three months of CPAP treatment. At 6 months, the only significant change was the SDNN measured after deep breathing (28.80 +/- 9.83 vs. 34.43 +/- 14.23 millisecond, p = 0.032). CONCLUSION: One aspect of heart rate variability in moderate to severe obstructive sleep apnea patients was improved after six month's continuous positive airway pressure treatment.

The cost-effectiveness of mini peak expiratory flow as a screening test for chronic obstructive pulmonary disease among the Bangkok elderly.

This study aims to explore the cost-effectiveness of Mini Peak Expiratory Flow (miniPEF) as a screening test for Chronic Obstructive Pulmonary Disease (COPD) among the elderly in 124 urban communities around Siriraj Hospital, using the gold standard of diagnosis based on the guidelines of the Thoracic Society of Thailand. There were 3,094 subjects who participated and completed all the tests. The results showed that the cut-off miniPEF percentage of predicted value of highest average accuracy was 62 per cent. The sensitivity was 72.7 per cent (95% CI 67.0-78.6) and the specificity was 81.1 per cent (95% CI 79.7-82.5) The cost of screening 19 elderly to detect one case of COPD is 923 baht, with a false negative rate of 1.9 per cent (95% CI 1.3-2.5%) and a false positive rate of 17.5 per cent (95% CI 15.4-19.6%). It is suggested that measuring a miniPEF is regarded as one of the cost-effective screening tests for COPD in the elderly.

The most cost-effective screening method for chronic obstructive pulmonary disease among the Bangkok elderly.

Our previous studies demonstrated the high prevalence and incidence of Chronic Obstructive Pulmonary Disease (COPD) among the Bangkok elderly, as well as the cost-effectiveness of a questionnaire, chest radiography, and mini peak expiratory flow rate (miniPEF) as screening tools. This final study aimed to identify the most cost-effective screening method among individual, serial and parallel combinations of the above tools, based on the guidelines for diagnosing COPD of the Thoracic Society of Thailand. There were 3,094 elderly aged 60 years and over in 124 urban communities around Siriraj Hospital who participated and completed all the tests. The results showed that the most cost-effective screening method was the miniPEF at cut-off percentage of 62 per cent of predicted value. This needed to screen 19 elderly people at a cost of 923 baht to detect one case of COPD, with a false negative rate of 1.9 per cent (95%CI 1.3-2.5), a false positive rate of 17.5 per cent (95%CI 15.4-19.6). The questionnaire is the alternative choice of screening tool.

The cost-effectiveness of a questionnaire as a screening test for chronic obstructive pulmonary disease among the Bangkok elderly.

This study aimed to explore the cost-effectiveness of using a questionnaire as a screening test for Chronic Obstructive Pulmonary Disease (COPD) among the Bangkok elderly residing around Siriraj Hospital. The gold standard used for diagnosing COPD followed the guidelines of the Thoracic Society of Thailand. The questionnaire consisted of 10 questions on smoking status, respiratory symptoms and previous history of pulmonary tuberculosis. There were 3,094 elderly who participated, completed the questionnaire, and underwent spirometry as well as chest radiography in the community. The results showed that elderly individuals who are smokers (> 0.5 pack-year) or have ever experienced sudden cough with chest oppression or dyspnea when the weather changes or who have expectorated more than two tablespoons of sputum would be suspected of having COPD with a sensitiviy of 81.4 per cent (95% CI 79.4-83.4), specificity of 62.2 per cent (95% CI 60.4-64.0) false negative rate 1.2 per cent (95% CI 0.7-1.7) and false positive rate 38 per cent (95% CI 35.3-40.7) and subsequently required spirometry and chest X-ray for definitive diagnosis. The test needed to screen 17 elderly individuals to detect one COPD case at a cost of 1,538 baht. This questionnaire is also a self-assessment tool for COPD screening among the elderly in order to encourage them to seek for early medical attention and it is recommended that this should be publicized via the mass media.

The cost-effectiveness of chest radiography as a screening test for chronic obstructive pulmonary disease among the Bangkok elderly.

Regular screening with chest radiography (CXR) in an annual physical check up of the elderly is most frequently practiced. This study aimed to identify the CXR indices and the cost-effectiveness of CXR as a screening test for Chronic Obstructive Pulmonary Disease (COPD) among the elderly in 124 urban communities of Bangkok around Siriraj Hospital. The gold standard for diagnosing COPD followed the guidelines of the Thoracic Society of Thailand. There were 3,094 subjects who participated, completed spirometry and a CXR. The selected nine indices from PA and lateral CXR for diagnosing COPD were based on the presence of hyperinflation. The positive criteria of each index were reported. The cut-off point of best average accuracy ie, Z score of the CXR was 0.07 with a sensitivity of 75.9 per cent (95% CI 70.2-81.6%), specificity of 72.4 per cent (95% CI 70.8-74.0%) and the best average accuracy of 74.1 per cent (95% CI 72.5-75.7%) whereas the cost-effective cut-off point of a Z score of CXR as a screening test for COPD was 0.04 at the lowest grand total cost. The cost to detect one case of COPD was 2,008 baht and needed to screen 17 elderly. It is suggested that CXR is probably not a suitable screening test for COPD in the elderly due to the complicated derivation of the CXR indices. However, its efficacy may be of some value in in-office diagnosis of COPD.

The prevalence and incidence of COPD among urban older persons of Bangkok Metropolis.

COPD substantially affects the national healthcare resource and healthcare cost especially among the older persons. Identifying the accurate prevalence and incidence reflects the scale of problem posed by COPD. This epidemiological study using the criteria for diagnosing COPD based on ratio of FEV1.0/FVC less than 70 per cent and the reversibility of less than 15 per cent increase of post bronchodilator FEV1.0 in the absence of parenchymal lesions and cardiomegaly in CXR (PA and lateral view) revealed the prevalence (1998) of COPD among the 3094 older persons aged 60 years and over in the communities of Bangkok Metropolis 10 km around Siriraj Hospital was 7.11 per cent (95% CI: 6.21-8.01), whereas the incidence (1999) of COPD was 3.63 per cent (95% CI: 2.83-4.43). Both the prevalence and the incidence were increased with increasing age.The disease occurred predominantly among male smokers. The distribution of mild : moderate : severe COPD in the prevalence study was 5.6:2.2:1. The current findings also suggest that tobacco smoking is the prime important cause of COPD and the indoor pollution especially cooking smoke is not significant. In particular, the unexpectedly high incidence compared with prevalence in this population probably represents the warning message to the national policy maker for prompt and effective health promotion and disease prevention to prevent further social and economic loss.

The prevalence of obstructive sleep apnea among professional hospital drivers.

Background : Several reports have suggested that about one-fifth of car accidents are sleep-related and obstructive sleep apnea (OSA) is one of the major causes of increased daytime sleepiness. Various reports from western countries have shown that different groups of drivers, especially truck drivers have a high prevalence of OSA, which may play a part in the occurrence of car accidents. Objectives : To determine the frequency of OSA and other sleep related problems in a group of professional drivers. Study design : Descriptive study. Methods : All 21 male professional drivers at one government hospital, aged between 27-57 years old, were recruited to the study. Data were collected by clinical examination, questionnaire and overnight polysomnography. OSA was defined as a Respiratory Disturbance Index (RDI) or an apnea / hypopnea index of over 5 events per hour. Results : The prevalence of OSA was 4%. Only 1 subject had severe OSA with an RDI of 102. None of them reported having car accidents but 71% reported symptoms of daytime sleepiness. Conclusion : OSA was not very common among professional drivers in this study but there were other sleep related problems reported which might relate to an increased risk of car accident. Further study of sleep disorders and their association with car accidents in a larger and broader group of drivers is needed.

Tranexamic acid in patients with hemoptysis.

Hemoptysis is a common respiratory symptom leading to admission to hospital. The main management of hemoptysis depends on treating the underlying cause. The use of tranexamic acid is recommended by many doctors without much information available. MATERIAL AND METHOD: This study was a randomized double blinded placebo controlled trial in using tranexamic acid (Transamine) in hemoptysis patients. The study period was one week. Patients with hemoptysis were separated into 3 groups depending on the amount of blood. Group 1 consisted of patients with blood streak sputum. Group 2 coughed up less than 20 ml of frank blood. Patients in Group 3 were those who coughed up 20-500 ml of blood per day. A record of the amount of bleeding and drug side effects was done. RESULTS: From June 1994 to May 1997, 46 patients with hemoptysis completed the study. There were 21 in the tranexamic acid group and 25 in the placebo group. The placebo group had a tendency not to have underlying lung disease and more patients who had a normal chest X-ray. The benefit of tranexamic acid in shortening the days of hemoptysis is not shown in this study. There was a low incidence of side effects of tranexamic acid in this study. CONCLUSION: This randomized double blinded placebo controlled trial could not demonstrate the benefit of tranexamic acid in shortening the days of hemoptysis and confirm the low incidence of side effects of this drug.

Differential cell analysis in bronchoalveolar lavage from various pulmonary diseases.

To obtain characteristics of cellular responses of the lung to various disease processes, we analyzed the cells in bronchoalveolar lavage fluid retrieved from various lung lesions. Patients affected with five groups of pulmonary diseases were included in this study. These were pulmonary tuberculosis (21), malignancy (7), interstitial lung disease (11), bacterial pneumonia (10), and invasive fungal infection (7). Diagnoses were made from histopathological or microbiological evidence and were followed by compatible clinical courses. We compared total cell counts, alveolar macrophages, neutrophils, and lymphocytes in both percentages and absolute numbers to the values in the normal population reported in previous studies. Comparisons within each disease were also made. Compared to the normal population reported in previous increased percentages of neutrophils and lymphocytes in nearly all groups. However, if the comparison was made among the five groups, only the bacterial pneumonia had a significantly higher total cell count, absolute count and percentage of neutrophils. A value of more than 50% neutrophils gave sensitivity and specificity as 80% and 89%, respectively, in differentiatind bacterial pneumonia from other diseases. No parameter was demonstrated as useful in distinguishing between nonbacterial conditions. In conclusion, increases in the percentage of neutrophils and lymphocytes were discovered in nearly all pulmonary diseases. The markedly increased percentage of neutrophils in bacterial pneumonia may be useful as adjunctive evidence in the diagnostic process in some special conditions.

Tuberculosis of the cervical lymph nodes.

Analysis of 188 patients with pathological diagnosis of tuberculosis or findings consistent with tuberculosis of the cervical lymph nodes during the period 1985-1988 disclosed the following pertinent findings: (1) The histo-pathological diagnoses, based on findings of chronic granuloma with or without the presence of acid-fast bacilli (AFB) on staining, were “probable tuberculosis” in 38.8 percent of the cases, and “consistent with tuberculosis” in 61.2 percent of them. It is worthy of note that proof for AFB in the 1973 report (from the same laboratory) was available only in 1.58 percent of the cases.1 (2) The supraclavicular group was the frequently diseased of the lymph nodes as found in a previous study;1 this finding also conforms to the high incidence of palpable supraclavicular lymph nodes in pulmonary tuberculosis patients.5 This persistent prevalence of the site of tuberculous involvement may be used as evidence in support of early post-primary haematogenous dissemination of the pathogenic organism, rather than the less occurring lymphogenous spread from the site of upper digestive tract infection, as recently suggested.4