Within-Visit Blood Pressure Variability and All-Cause and Stroke Mortality: Thai Epidemiologic Stroke Study.

INTRODUCTION: The association between within-visit blood pressure variability (BPV) and all-cause and stroke mortality remains uncertain. The aim of our study was to assess the association of within-visit BPV with all-cause and stroke mortality. METHODS: The study was conducted among participants from Thai Epidemiologic Stroke Study, which is a prospective community-based cohort study that recruited participants from the general population from five regions of Thailand. This study included 19,614 participants aged 45-80 years, who were free of stroke and had three blood pressure (BP) measurements, taken 1 min apart, at baseline. Within-visit systolic blood pressure (SBP) and diastolic blood pressure (DBP) variability were expressed as the maximum absolute difference (MAD) between any two readings among the three repeated sequential measurements of SBP and DBP, respectively. The participants were followed up for mortality. Cox regression analysis was used to identify the association of within-visit BPV with all-cause and stroke mortality. Hazard ratio (HR) and 95% confidence intervals were used to illustrate the associations. Sensitivity analysis restricted to participants with mean SBP above 130 mm Hg and mean DBP above 90 mm Hg (n = 1,895) was performed. RESULTS: During a median follow-up of 11.1 years, 305 participants died of stroke, and 3,173 participants died of nonstroke cause. In unadjusted analyses, high within-visit MAD of SBP was significantly associated with all-cause (HR, 1.19; 95% CI, 1.09-1.31; p < 0.001) and stroke mortality (HR, 1.87; 95% CI, 1.35-2.59; p < 0.001); high within-visit MAD of DBP was also significantly associated with all-cause mortality (HR, 1.19; 95% CI, 1.08-1.31; p < 0.001), in quartile 4 versus quartile 1. These associations did not persist after further adjustment for sex, age, and other potential confounders including mean BP. However, sensitivity analysis showed some inconsistent results regarding associations of within-visit MAD of SBP and DBP with all-cause and stroke mortality, respectively. CONCLUSION: In general population, within-visit systolic BPV and within-visit diastolic BPV do not have prognostic significance on stroke mortality and all-cause mortality, respectively.

Infectious causes of encephalitis and meningoencephalitis in Thailand, 2003-2005.

Acute encephalitis is a severe neurologic syndrome. Determining etiology from among ≈100 possible agents is difficult. To identify infectious etiologies of encephalitis in Thailand, we conducted surveillance in 7 hospitals during July 2003-August 2005 and selected patients with acute onset of brain dysfunction with fever or hypothermia and with abnormalities seen on neuroimages or electroencephalograms or with cerebrospinal fluid pleocytosis. Blood and cerebrospinal fluid were tested for >30 pathogens. Among 149 case-patients, median age was 12 (range 0-83) years, 84 (56%) were male, and 15 (10%) died. Etiology was confirmed or probable for 54 (36%) and possible or unknown for 95 (64%). Among confirmed or probable etiologies, the leading pathogens were Japanese encephalitis virus, enteroviruses, and Orientia tsutsugamushi. No samples were positive for chikungunya, Nipah, or West Nile viruses; Bartonella henselae; or malaria parasites. Although a broad range of infectious agents was identified, the etiology of most cases remains unknown.

Association between Socioeconomic Status and Major Risk Factors of Stroke: Thai Epidemiologic Stroke (TES) Study.

OBJECTIVE: To investigate the association of socioeconomic status (SES) (education, personal income, and occupation) with four major risk factors of stroke, those are diabetes, hypertension, hypercholesterolemia, and current smoker MATERIAL AND METHOD: The Thai Epidemiologic Stroke Study is a community-based cohort study, which recruitedparticipants from the general population from five geographic regions around the country. Cross-sectional baseline data of 19,997 (6,803 men and 13,194 women) participants, aged 45 to 80 years were included in the present analysis. Multiple logistic regression analysis was used to estimate association ofsocioeconomic indicators with the major risk factors of stroke. RESULTS: SES was associated with a major risk factor of stroke. Among three indicators ofsocioeconomic status, education was more consistently associated with the risk factors than personal income and occupation, particularly in women. Education significantly inversely associated with diabetes (p = 0.015 in men and 0.002 in women, respectively), and current smoker in both sexes (p < 0.001), and with hypertension in women (p = 0.011). By contrast, education was significantly positively associated with hypercholesterolemia in women (p < 0.001). CONCLUSION: The differences in the prevalence of the major risk factors of stroke between SES groups were important, and should be considered in the development ofpolicies or tailored strategies for prevention of stroke.

Factors predicting high estimated 10-year stroke risk: thai epidemiologic stroke study.

BACKGROUND: The purpose of the study was to determine the factors predicting high estimated 10-year stroke risk based on a risk score, and among the risk factors comprising the risk score, which factors had a greater impact on the estimated risk. METHODS: Thai Epidemiologic Stroke study was a community-based cohort study, which recruited participants from the general population from 5 regions of Thailand. Cross-sectional baseline data of 16,611 participants aged 45-69 years who had no history of stroke were included in this analysis. Multiple logistic regression analysis was used to identify the predictors of high estimated 10-year stroke risk based on the risk score of the Japan Public Health Center Study, which estimated the projected 10-year risk of incident stroke. RESULTS: Educational level, low personal income, occupation, geographic area, alcohol consumption, and hypercholesterolemia were significantly associated with high estimated 10-year stroke risk. Among these factors, unemployed/house work class had the highest odds ratio (OR, 3.75; 95% confidence interval [CI], 2.47-5.69) followed by illiterate class (OR, 2.30; 95% CI, 1.44-3.66). Among risk factors comprising the risk score, the greatest impact as a stroke risk factor corresponded to age, followed by male sex, diabetes mellitus, systolic blood pressure, and current smoking. CONCLUSIONS: Socioeconomic status, in particular, unemployed/house work and illiterate class, might be good proxy to identify the individuals at higher risk of stroke. The most powerful risk factors were older age, male sex, diabetes mellitus, systolic blood pressure, and current smoking.

Risk of metabolic syndrome for stroke is not greater than the sum of its components: Thai Epidemiologic Stroke (TES) study.

Limited information is available on the association between the metabolic syndrome (MetS) and stroke. Whether or not MetS confers a risk greater than the sum of its components is controversial. This study aimed to assess the association of MetS with stroke, and to evaluate whether the risk of MetS is greater than the sum of its components. The Thai Epidemiologic Stroke (TES) study is a community-based cohort study with 19,997 participants, aged 45-80 years, recruited from the general population from 5 regions of Thailand. Baseline survey data were analyzed in cross-sectional analyses. MetS was defined according to criteria from the National Cholesterol Education Program (NCEP) Adult Treatment Panel III, the American Heart Association/National Heart, Lung, and Blood Institute (revised NCEP), and International Diabetes Federation (IDF). Logistic regression analysis was used to estimate association of MetS and its components with stroke. Using c statistics and the likelihood ratio test we compared the capability of discriminating participants with and without stroke of a logistic model containing all components of MetS and potential confounders and a model also including the MetS variable. We found that among the MetS components, high blood pressure and hypertriglyceridemia were independently and significantly related to stroke. MetS defined by the NCEP (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.32-2.04), revised NCEP (OR, 2.27; 95% CI, 1.80-2.87), and IDF definitions (OR, 1.70; 95% CI, 1.37-2.13) was significantly associated with stroke after adjustment for age, sex, geographical area, education level, occupation, smoking status, alcohol consumption, and low-density lipoprotein cholesterol. After additional adjustment for all MetS components, these associations were not significant. There were no statistically significant difference (P=.723-.901) in c statistics between the model containing all MetS components and potential confounders and the model also including the MetS variable. The likelihood ratio test also showed no statistically significant (P=.166-.718) difference between these 2 models. Our findings suggest that MetS is associated with stroke, but not to a greater degree than the sum of its components. Thus, the focus should be on identification and appropriate control of its individual components, particularly high blood pressure and hypertriglyceridemia, rather than of MetS itself.

Appropriate body mass index and waist circumference cutoffs for middle and older age group in Thailand: data of 19,621 participants from Thai epidemiologic stroke (TES) study.

OBJECTIVE: To determine the appropriate body mass index (BMI) and waist circumference (WC) cutoff point for identification of at least one cardiovascular risk factor (hypertension, dyslipidemia, and type 2 diabetes) in Thailand, and to compare the discrimination ability of BMI with that of WC for discrimination of at least one cardiovascular risk factor. MATERIAL AND METHOD: Baseline health survey data of participants of Thai Epidemiologic Stroke (TES) Study, who were free from stroke, enrolled from five geographic regions around the country, were studied as cross-sectional analysis. Receiver operating characteristics curve (ROC) analysis was performed to determine the appropriate cutoff points of BMI and WC in identifying those with presence of at least one cardiovascular risk factors. The BMI or WC value with the shortest distance on the ROC curve was considered to be appropriate cutoffs. Comparing the ability of BMI in discrimination of at least one cardiovascular risk factor with that of WC was performed by comparing ROC area under curve (AUC). RESULTS: Among 19,621 (6,608 men and 13,013 women) participants with age range of 45 to 80 years, the average age was 59.8 years for men and 58.5 years for women. The appropriate cutoff point of BMI was 23 kg/m2 in men and 24 kg/m2 in women. The cutoffs of WC were 80 cm and 78 cm in men and women, respectively. In both gender, waist circumference (WC) (AUC in men = 0.684; 95% CI, 0.672-0.695, AUC in women = 0.673; 95% CI, 0.665-0.681) was significantly (p < 0.001) better than BMI (AUC in men = 0.667; 95% CI, 0.656-0.679, AUC in women = 0.636; 95% CI, 0.628-0.644) in discrimination of at least one cardiovascular risk factor. CONCLUSION: In Thai adults aged 45 to 80 years, the cutoff points of BMI should be 23 kg/m2 in men and 24 kg/m2 in women. For WC, 80 cm and 78 cm should be considered to be appropriate cutoffs for men and women, respectively. Waist circumference (WC) as a simple obesity index should be advocated for public health screening.

Good recovery of immunization stress-related responses presenting as a cluster of stroke-like events following CoronaVac and ChAdOx1 vaccinations.

BACKGROUND: Immunization stress-related responses presenting as stroke-like symptoms could develop following COVID-19 vaccination. Therefore, this study aimed to describe the clinical characteristics of immunization stress-related responses causing stroke-like events following COVID-19 vaccination in Thailand. METHODS: We conducted a retrospective study of the secondary data of reported adverse events after COVID-19 immunization that presented with neurologic manifestations. Between March 1 and July 31, 2021, we collected and analyzed the medical records of 221 patients diagnosed with stroke-like symptoms following immunization. Two majority types of vaccines were used at the beginning of the vaccination campaign, including CoronaVac (Sinovac) or ChAdOx1 (AstraZeneca). Demographic and medical data included sex, age, vaccine type, sequence dose, time to event, laboratory data, and recovery status as defined by the modified Rankin score. The affected side was evaluated for associations with the injection site. RESULTS: Overall, 221 patients were diagnosed with immunization stress-related responses (stroke-like symptoms) following CoronaVac (Sinovac) or ChAdOx1 (AstraZeneca) vaccinations. Most patients (83.7%) were women. The median (interquartile range) age of onset was 34 (28-42) years in patients receiving CoronaVac and 46 (33.5-60) years in those receiving ChAdOx1. The median interval between vaccination and symptom onset for each vaccine type was 60 (16-960) min and 30 (8.8-750) min, respectively. Sensory symptoms were the most common symptomology. Most patients (68.9%) developed symptoms on the left side of the body; 99.5% of the patients receiving CoronaVac and 100% of those receiving ChAdOx1 had a good outcome (modified Rankin scores ≤2, indicating slight or no disability). CONCLUSIONS: Immunization stress-related responses presenting as stroke-like symptoms can develop after COVID-19 vaccination. Symptoms more likely to occur on the injection side are transient (i.e., without permanent pathological deficits). Public education and preparedness are important for administering successful COVID-19 vaccination programs.

Prevalence of stroke and stroke risk factors in Thailand: Thai Epidemiologic Stroke (TES) Study.

OBJECTIVE: To assess stroke prevalence and stroke risk factors in Thailand. MATERIAL AND METHOD: Thai Epidemiologic Stroke (TES) Study is an ongoing, community based cohort study that has been conducted in five geographic regions of Thailand. Baseline health status survey was started in 2004 and enrollment continued until the end of 2006. All participants who were suspicious of being stroke victims were verified. In this analysis, baseline data of 19,997 participants aged 45 to 80 years were identified and analyzed as a cross-sectional analysis. RESULTS: Three hundred and seventy six subjects were proved to have a stroke thus resulting the crude prevalence of stroke to be 1.88% (95% CI, 1.69 to 2.07). Age standardization to Segi world standard population was 1.81% (95% CI, 1.62 to 1.99). Crude prevalence among adults aged > or = 65 years was 2.70% (95% CI, 2.28 to 3.11). Stroke prevalence differed among five geographic regions of the country (Bangkok 3.34%, Central region 2.41%, Southern 2.29%, Northern 1.46% and Northeastern 1.09%). Using multiple logistic regression analysis, factors associated with higher stroke prevalence were male gender (p < 0.001), occupational class (p < 0.001), geographic region (p < 0.001), hypertension (p < 0.001), diabetes mellitus (p = 0.002) and hypercholesterolemia (p = 0.026). CONCLUSION: Stroke prevalence in Thailand from TES study is higher than previous studies, but it is lower than developed countries, probably due to high case fatality rate in Thai population. Geographic variation in stroke prevalence is found more in Bangkok, Central and Southern regions. Longitudinal follow-up of TES cohort study will provide further information on risk factors and incidence of stroke.

Plasma homocysteine and ischemic stroke patients in Thailand.

BACKGROUND: Hyperhomocysteinemia was recently found to be a risk factor for stroke; however, the available data from Thailand is scarce. OBJECTIVE: To study plasma homocysteine levels in ischemic stroke and compare it with age-and sex-matched controls, and to identify the association of plasma homocysteine and subtype of stroke. MATERIAL AND METHOD: The authors studied plasma homocysteine levels of ischemic stroke patients with clinical signs and symptoms of stroke as confirmed by CT scan and compared them with control subjects who presented with other diseases and no clinical signs and symptoms of stroke between June 2000- May 2001 in Prasat Neurological institute. Fasting plasma homocysteine was measured by HPLC technique. Abnormal cut off point of plasma homocysteine was identified and associations of plasma homocysteine and stroke were studied by using logistic regression analyses. RESULTS: Two hundred and sixty-eight patients were recruited in the present study (132 controls and 136 ischemic stroke patients). The abnormal cut off point of plasma homocysteine was > 14 micromol/L. The authors found statically significant association of abnormal plasma homocysteine and stroke (p<0.001) with odds ratio of 4.277 (95%CI 2.551-7.171). After adjusting the confounding factor the authors found that high homocysteine was significantly associated with ischemic stroke (p<0.001) with odd ratio of 3.401 (95%CI 1.954-5.922). In the subgroup analyses of type of stroke and abnormal homocysteine, the authors demonstrated that abnormal homocysteine levels were more pronounced in the large vessel subtype than the small group. CONCLUSION: Abnormal homocysteine level is an independent risk factor of ischemic stroke and more correlated with large vessel subtype.

Diagnostic utility of NMO/AQP4-IgG in evaluating CNS inflammatory disease in Thai patients.

Epidemiological studies in Thailand have reported that inflammatory demyelinating diseases (IDDs) commonly affect the optic nerve and spinal cord. We investigated the diagnostic utility of aquaporin (AQP)-4-IgG testing in 31 consecutive patients evaluated for CNS IDDs in 3 academic Thai hospital neurology clinics between February 2008 and January 2009. Patients were classified into 3 clinical diagnostic groups: Neuromyelitis optica (NMO, n=10) multiple sclerosis (MS, n=5) and unclassified IDD (n=16). All sera were tested blindly by cell binding (Euroimmun) assay (CBA). Sera were also tested by indirect immunofluorescence assay (IFA) and ELISA (RSR/Kronus). After initial screening by CBA, AQP4-IgG was detected in 6 NMO patients (60%); 3 of the 4 seronegative cases were receiving immunosuppressants. AQP4-IgG was detected in 13 unclassified IDD cases (81%), but in no MS cases. Cell binding assay and ELISA were more sensitive than IFA (p=0.0004). The 81% seropositivity rate in "unclassified" patients suggests that AQP4 autoimmunity accounts for a significant proportion of Thai CNS inflammatory demyelinating disease, especially those with optic neuritis or transverse myelitis, with or without abnormal brain MRI, in whom a specific diagnosis or clear-cut treatment approach is unclear.