Acute air pollution-related symptoms among residents in Chiang Mai, Thailand.

Open burnings (forest fires, agricultural, and garbage burnings) are the major sources of air pollution in Chiang Mai, Thailand. A time series prospective study was conducted in which 3025 participants were interviewed for 19 acute symptoms with the daily records of ambient air pollutants: particulate matter less than 10 microm in size (PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3). PM10 was positively associated with blurred vision with an adjusted odds ratio (OR) of 1.009. CO was positively associated with lower lung and heart symptoms with adjusted ORs of 1.137 and 1.117. NO2 was positively associated with nosebleed, larynx symptoms, dry cough, lower lung symptoms, heart symptoms, and eye irritation with the range of adjusted ORs (ROAORs) of 1.024 to 1.229. SO2 was positively associated with swelling feet, skin symptoms, eye irritation, red eyes, and blurred vision with ROAORs of 1.205 to 2.948. Conversely, O3 was negatively related to running nose, burning nose, dry cough, body rash, red eyes, and blurred vision with ROAORs of 0.891 to 0.979.

Association of fluoride in water for consumption and chronic pain of body parts in residents of San Kamphaeng district, Chiang Mai, Thailand.

OBJECTIVE: To assess the dose response of fluoride exposure from water and chronic pain. METHODS: Using a retrospective cohort design, the study was conducted in two sub-districts of San Kamphaeng district, Poo-kha and On-tai. Five hundred and thirty-four residents aged ≥50 years of age were interviewed about their sources of drinking water and assessed for chronic pain. Each water source was sampled for fluoride measurement, from which the average daily fluoride dose was estimated. Binary logistic regression with forward stepwise (likelihood ratio) model selection technique was used to examine the association between the average daily fluoride dose and chronic pain. RESULTS: We found associations between the average daily fluoride dose and lower back pain [odds ratio (OR) = 5.12; 95% confidence interval (CI), 1.59-16.98], and between the high fluoride area vs. the low fluoride area (OR = 1.58; 95% CI, 1.10-2.28; relative risk= 1.22 with 95% CI, 1.14-1.31) to lower back pain. Other risk factors, such as family history of body pain and a history of injury of the lower body, were also associated with lower back pain. However, there were no relationships between the average daily fluoride dose and leg and knee pains. CONCLUSION: To prevent further lower back pain, we recommend that the water in this area be treated to reduce its fluoride content.

SARIMA Model Forecasting Performance of the COVID-19 Daily Statistics in Thailand during the Omicron Variant Epidemic.

This study aims to identify and evaluate a robust and replicable public health predictive model that can be applied to the COVID-19 time-series dataset, and to compare the model performance after performing the 7-day, 14-day, and 28-day forecast interval. The seasonal autoregressive integrated moving average (SARIMA) model was developed and validated using a Thailand COVID-19 open dataset from 1 December 2021 to 30 April 2022, during the Omicron variant outbreak. The SARIMA model with a non-statistically significant p-value of the Ljung-Box test, the lowest AIC, and the lowest RMSE was selected from the top five candidates for model validation. The selected models were validated using the 7-day, 14-day, and 28-day forward-chaining cross validation method. The model performance matrix for each forecast interval was evaluated and compared. The case fatality rate and mortality rate of the COVID-19 Omicron variant were estimated from the best performance model. The study points out the importance of different time interval forecasting that affects the model performance.

Trigger of a migraine headache among Thai adolescents smartphone users: a time series study.

The study aims to investigate the effect of modern technology in the trigger of migraine headaches in high school students by using generalized estimating equation analysis. The prospective time series study was conducted in one hundred and forty-five smartphones using high school students in Chiang Mai Province who each completed a headache diary giving a total of 12,969 data entries. The smartphone output power was measured and recorded by a smartphone application. Smartphone use, sleep quality, anxiety, and depression also were assessed. Results revealed that the prevalence of repeated headache be 13.4% and migraine 16.9%. The migraine had the strongest association with handfree device use and internet use, followed by age and anxiety. Furthermore, the strongest effect of smartphone output power in triggering a migraine was found at ≤ 1.79×10-5 and 1.80-1.99×10-5 mW ranges. Meanwhile, Lag_6 of daily smartphone output power exposure produced the migraine effect in a reverse dose-response manner. The smartphone electromagnetic radiation was a primary migraine trigger. The study results led to the recommendation to avoid triggers by use of smartphone talking with hand-free devices to prevent a recurrent migraine.

Air pollution-related peak expiratory flow rates among asthmatic children in Chiang Mai, Thailand.

The severity of air pollution in northern Thailand has long been recognized; in spite of that there have been no epidemiological studies regarding the associations between the air pollution and health effects in the area. The authors followed a cohort of 31 asthmatic children (4-11 years of age) residing in Muang district, Chiang Mai, Thailand, from 29 August 2005 to 30 June 2006, for 306 days. The daily air pollutants, including particulate matter with aerodynamic diameter < 2.5 microm, particulate matter with aerodynamic diameter < 10 microm, carbon monoxide, ozone (O(3)), nitrogen dioxide, and sulfur dioxide (SO(2)), and the meteorological parameters, including pressure, temperature, relative humidity, rain quantity, and sunshine duration, were recorded. The peak expiratory flow rates (PEFRs) were fitted with pollutants and meteorological covariates using general linear mixed models to account for random effects and autocorrelation. The authors found that there were inverse associations of SO(2) and evening PEFR, with a coefficient of -2.12 (95% confidence interval (CI) = -3.22 to -0.28); of SO(2) and daily percent deviation of PEFR, with a coefficient of -0.73 (95% CI = -1.33 to -0.12); and of O(3) combining with SO(2) and daily average PEFR, with a coefficient of -0.16 (95% CI = -0.31 to -0.00) and -1.60 (95% CI = -3.10 to -0.11), respectively. The associations of O(3) and SO(2) with PEFR were found even when SO(2) concentrations never exceeded the standard level.

Association between urinary cadmium and chronic musculoskeletal pain in residents of cadmium-contaminated area in Northwest Thailand.

Cadmium exposure is known to cause adverse health effects in different organs of the human body but whether the effects result in chronic musculoskeletal pain (CMP) remain inclusive. The present study, therefore, aims to examine the relationship between urinary cadmium levels and CMP. An observational retrospective cohort study was conducted in two areas having different levels of cadmium contamination for comparison. The subjects enrolled into the study were individuals ages 18 and above who have lived in the studied areas for 1 year or more. The evaluation of chronic pain was carried out using a questionnaire and urine samples were collected for analysis of urinary cadmium levels. The data were analyzed using multiple logistic regression. The likelihood of CMP increased in a correlation with elevations in urinary cadmium from < 0.359, 0.359-0.753, 0.754-1.742, and ≥ 1.743 µg/g creatinine, adjusted odds ratio 1.07 (95% CI 0.62-1.86), 1.33 (95% CI 0.76-2.32), and 2.26 (95% CI 1.28-3.99) respectively. A positive association was found in our study between urinary cadmium level and CMP suggesting that cadmium exposure might cause neurological damage and/or tissue/muscle injury which in turn causing CMP.

Symptom-based data preprocessing for the detection of disease outbreak.

Early warning systems for outbreak detection is a challenge topic for researchers in the epidemiology and biomedical informatics fields. We are proposing a new method for detecting disease epidemics using a symptom-based approach. The data was collected from developed mobile applications which include users' demographic information and a list of chief complaint symptoms. Deliberated outbreaks are differentiated from seasonal outbreak by specific symptoms that represent a sign of infection. These symptoms were grouped, classified, and then converted to a time-series digital signal using the consensus scoring approach. Through the syndromic grouping method, the system digitized each data package into a single independent variable that is ready for further one-dimensional signal processing to predict disease outbreaks in the future.

Recommended Rice Intake Levels Based on Average Daily Dose and Urinary Excretion of Cadmium in a Cadmium-Contaminated Area of Northwestern Thailand.

This study was performed to investigate the dose-response relationship between average daily cadmium dose (ADCD) from rice and the occurrence of urinary cadmium (U-Cd) in individuals eating that rice. This was a retrospective cohort designed to compare populations from two areas with different levels of cadmium contamination. Five-hundred and sixty-seven participants aged 18 years or older were interviewed to estimate their rice intake, and were assessed for U-Cd. The sources of consumed rice were sampled for cadmium measurement, from which the ADCD was estimated. Binary logistic regression was used to examine the association between ADCD and U-Cd (cut-off point at 2 µg/g creatinine), and a correlation between them was established. The lowest estimate was ADCD = 0.5 µg/kg bw/day [odds ratio (OR) = 1.71; with a 95% confidence interval (CI) 1.02-2.87]. For comparison, the relationship in the contaminated area is expressed by ADCD = 0.7 µg/kg bw/day, OR = 1.84; [95 % CI, 1.06-3.19], while no relationship was found in the non-contaminated area, meaning that the highest level at which this relationship does not exist is ADCD = 0.6 µg/kg bw/day [95% CI, 0.99-2.95]. Rice, as a main staple food, is the most likely source of dietary cadmium. Abstaining from or limiting rice consumption, therefore, will increase the likelihood of maintaining U-Cd within the normal range. As the recommended maximum ADCD is not to exceed 0.6 µg/kg bw/day, the consumption of rice grown in cadmium-contaminated areas should not be more than 246.8 g/day. However, the exclusion of many edible plants grown in the contaminated area from the analysis might result in an estimated ADCD that does not reflect the true level of cadmium exposure among local people.

Stigma, social support, and treatment adherence among HIV-positive patients in Chiang Mai, Thailand.

Our study assessed the influence of HIV-related stigma on treatment adherence among people living with HIV in Chiang Mai, Thailand, and whether social support had a moderating effect on this relationship. We recruited 128 patients living with HIV from Sansai Hospital, a community hospital in Chiang Mai, Thailand, and collected data through structured interviews. All forms of HIV-related stigma considered in this study (personalized experience, disclosure, negative self-image, and public attitudes) were negatively correlated with adherence to anti-retroviral regimens. Multiple linear regression indicated that total HIV-related stigma was more predictive of treatment adherence than any individual stigma type, after adjusting for socio-demographic and health characteristics. Tests of interaction showed that social support did not appear to moderate the association between HIV stigma and treatment adherence. Our findings suggest that community and government efforts to improve public perceptions about people living with HIV might promote treatment adherence behaviors among HIV-positive patients.

Factors related to osteoporosis of postmenopausal women in Phayao, Thailand.

INTRODUCTION: This study was to investigate the associations between personal factors, health-related factors, history of fractures, and lifestyles and osteoporosis in the postmenopausal women. METHODS: This study was based on a retrospective case-control study design conducted in the Phayao Hospital, Phayao Province, Thailand. The 136 menopausal women aged 40 years and older were examined for bone density with dual x-ray absorptiometry. Those who had test results less than or equal to -2.5 standard deviation when compared to the maximum mean bone mineral density of young women (T score ≤ -2.5) were classified as the case group, and those who had test results more than -2.5 standard deviation when compared to the maximum mean bone mineral density of young women (T score > -2.5) were classified as the control group. Data were collected using questionnaires. Binary logistic regression with forward stepwise (likelihood ratio) model selection was used to explore the associated factors. RESULTS: The factors statistically related to osteoporosis were body mass index (BMI; adjusted odds ratio (OR) = 0.81; 95 % confidence interval (CI), 0.71-0.93), age at menopause (OR = 0.88; 95 % CI, 0.79-0.99), history of fractures (OR = 10.00; 95 % CI, 2.71-36.94), family history of osteoporosis (OR = 2.66; 95 % CI, 1.04-6.77), and non-consumption of foods containing legumes, dried beans, and grains (OR = 13.84; 95 % CI, 2.08-92.11). CONCLUSIONS: It is recommended that more studies should be conducted on finding the optimal BMI and on the consumption of legumes, dried beans, and grains as osteoporotic protective factors.

Acute effects of air pollution on peak expiratory flow rates and symptoms among asthmatic patients in Chiang Mai, Thailand.

The open burnings and forest fires have been recognized as the major sources of severe air pollution in the upper north of Thailand; however, there have been no clear evidences to show the associations between the air pollution and health effects in the area. We assessed the effects of air pollutants on the peak expiratory flow rates (PEFR) and symptoms in asthmatics. A cohort of 121 asthmatics was followed daily, for 306 days, for their PEFR and asthma symptoms. The daily air pollutants, including particulate matter with aerodynamic diameter <2.5 µm, particulate matter with aerodynamic diameter <10 µm (PM(10)), carbon monoxide, ozone, nitrogen dioxide (NO(2)), and sulfur dioxide (SO(2)), and the meteorological parameters, including pressure, temperature, relative humidity, rain quantity, and sunshine duration, were monitored. The PEFRs were fitted with general linear mixed models. The asthma symptoms were analyzed with the generalized estimating equations. There were positive associations of NO(2) with morning PEFR, with a coefficient of 0.06 [95% confidence interval (CI), 0.00-0.12]; of SO(2) with evening PEFR [with a range of coefficients of 0.88-1.00 (95% CI, 0.31-1.54)] and daily average PEFR [with a coefficient of 0.47 (95% CI, 0.00-0.94)]; of PM(10) with evening PEFR, with a coefficient of 0.02 (95% CI, 0.00-0.04). There was also negative association of PM(10) with ΔPEFR, with a coefficient of -0.01 (95% CI, -0.01 to -0.00). No pollutants were related to asthma symptoms. More studies are needed, particularly at low dose in adult asthmatics, to validate our findings.