Prevalence of and factors associated with scrub typhus exposure among the hill tribe population living in high incidence areas in Thailand: a cross-sectional study.

BACKGROUND: Scrub typhus is a significant tropical disease, occurring in rural settings and therefore usually afflicting remote agricultural populations who have lower socioeconomic status and limited access to medical care. A large proportion of the hill tribe people in Thailand are financially poor, have limited education, and do not have adequate health care access. This study aimed to estimate the prevalence of and determine factors associated with scrub typhus exposure among the hill tribe population living in high-incidence areas in northern Thailand. METHODS: A cross-sectional study design was used to gather information from hill tribe people aged 18 years and over living in ten hill tribe villages in Mae Fah Luang, Chiang Rai Province, Thailand. Participants who met the inclusion criteria were invited to participate in the study. A validated questionnaire was used as the research instrument, and 5 mL blood samples were taken. Orientia tsutsugamushi IgM and IgG antibodies were detected by enzyme-linked immunosorbent assay (ELISA) and then confirmed by immunofluorescence assay (IFA). Logistic regression was used to detect associations between variables at a significance level of α = 0.05. RESULTS: A total of 485 hill tribe people participated in the study; 57.1% were female, 29.9% were over 60 years of age, 46.4% were from the Akha tribe, and 74.2% had never attended school. The overall prevalence of scrub typhus exposure was 48.0%. In the multivariate model, five variables were found to be associated with scrub typhus exposure. Participants aged over 60 years had a 4.31-fold increased risk (95% CI = 1.73-10.72) of scrub typhus exposure compared to those who were younger than 30 years. Those who were illiterate had a 3.46-fold increased risk (95% CI = 1.93-6.21) of scrub typhus exposure than those who had at least a primary education level. Participants from the Akha tribe had a 2.20-fold increased risk (95% CI = 1.31-3.72) of scrub typhus exposure than those from the Lahu tribe. Subjects who had a history of cutting grass had a 1.85-fold increased risk (95% CI = 1.20-2.84) of scrub typhus exposure. Those who never wore gloves for farming had a 2.12-fold increased risk (95% CI = 1.28-3.49) of scrub typhus exposure than those who wore gloves daily. CONCLUSIONS: There is a high prevalence of scrub typhus exposure among the hill tribe in Thailand. Effective public health interventions to promote scrub typhus awareness and prevention are urgently needed in these populations.

Moderating Effects of Cortisol on Neural-Cognitive Association in Cognitively Normal Elderly Subjects.

Cortisol homeostasis is important for healthy brain and cognitive aging. The aim of the current study is to investigate the role of serum cortisol levels in the relationship between regional brain volumes and cognitive processing speed in a group of cognitively normal elderly subjects. Forty-one healthy elderly participants were from a parallel longitudinal study. The reported data in this study reflects baseline measurements. Whole-brain anatomical scanning was performed using a 3.0 Tesla Philips Medical Systems Achieva scanner. Cognitive processing speed was assessed by the digit-symbol and symbol search tests, from the Chinese version of the Wechsler Adult Intelligence Scale-third edition (WAIS-III). Serum cortisol levels (sampled in the late morning) were measured by ELISA kits. Whole-brain regression analysis revealed that serum cortisol levels positively predicted the white matter volumes (WMV) of the right thalamus, the gray matter volumes (GMV) of the left thalamus and right cerebellar tonsil, and negatively predicted the WMV and GMV of the left middle temporal gyrus (MTG) in 41 healthy elderly participants. Furthermore, serum cortisol significantly moderated the relationship between the GMV of the left MTG and processing speed, as well as the GMV of the left thalamus and processing speed. This study provided the first piece of evidence supporting serum cortisol levels in moderating the relationship between regional brain volumes and processing speed in healthy elderly subjects. This observation enriches our understanding of the role of cortisol in brain morphology and cognitive functioning.

Validity of the Cantonese Chinese Montreal Cognitive Assessment in Southern Chinese.

AIM: The objective of the present study was to investigate the reliability and the validity of the Cantonese Chinese Montreal Cognitive Assessment (MoCA) as a brief screening tool of amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) in Southern Chinese older adults. METHODS: Cognitively normal, aMCI and AD Cantonese-speaking Chinese older adults were recruited from a memory clinic and the community. The English MoCA was translated into Cantonese Chinese and then back-translated. We then evaluated the content validity, reliability, sensitivity and specificity of the Chinese Cantonese MoCA. RESULTS: We recruited 115 cognitively normal controls, 87 aMCI and 64 AD patients. Only education was positively correlated with the Cantonese MoCA score (r = 0.46, P < 0.001). The Chinese Cantonese MoCA had a high internal consistency with a Cronbach's alpha of 0.85. In the test-retest reliability assessment, the intraclass correlation coefficient (ICC) was 0.95 (P < 0.001). The ICC for the interrater reliability was 0.96 (P < 0.001). Receiving operating characteristic curve analyses showed an area under the curve of 0.85 and 0.99 for aMCI and AD, respectively (both P < 0.001). The optimal cut-off score for detection of aMCI was 22/23, which yielded a sensitivity and specificity of 78% and 73%, respectively. The optimal cut-off score for detection of AD was 19/20, which gave sensitivity and specificity of 94% and 92%, respectively. CONCLUSION: The Cantonese Chinese MoCA is a consistent and reliable instrument. In terms of its validity, the MoCA is better in the detection of AD than aMCI in Cantonese-speaking Chinese persons. It is only fair for the screening of aMCI.

The putative neurodegenerative links between depression and Alzheimer's disease.

Alzheimer's disease (AD) is the leading neurodegenerative cause of dementia in the elderly. Thus far, there is no curative treatment for this devastating condition, thereby creating significant social and medical burdens. AD is characterized by progressive cognitive decline along with various neuropsychiatric symptoms, including depression and psychosis. Depression is a common psychiatric disorder affecting individuals across the life span. Although the "monoamine hypothesis" of depression has long been proposed, the pathologies and mechanisms for depressive disorders remain only partially understood. Pharmacotherapies targeting the monoaminergic pathways have been the mainstay in treating depression. Additional therapeutic approaches focusing other pathological mechanisms of depression are currently being explored. Interestingly, a number of proposed mechanisms for depression appear to be similar to those implicated in neurodegenerative diseases, including AD. For example, diminishing neurotrophic factors and neuroinflammation observed in depression are found to be associated with the development of AD. This article first provides a concise review of AD and depression, then discusses the putative links between the two neuropsychiatric conditions.

Electroacupuncture for primary insomnia: a randomized controlled trial.

STUDY OBJECTIVES: To evaluate the short-term efficacy and safety of electroacupuncture for the treatment of primary insomnia. DESIGN: Randomized, single-blind, placebo-controlled, parallel-group. SETTING: A university-based sleep clinic. PARTICIPANTS: Community sample of 60 Chinese adult volunteers who report having insomnia 3 or more nights per week, whose symptoms meet the DSM-IV criteria for primary insomnia for at least 3 months, and who have an Insomnia Severity Index total score of at least 15. Participants were screened with polysomnography and the Structured Clinical Interview for the DSM-IV prior to randomization. INTERVENTION: Electroacupuncture at Yintang (EX-HN3), Baihui (GV20), bilateral ear Shenmen, Sishencong (EX-HN1), and Anmian (EX) 3 times per week for 3 weeks or placebo acupuncture using Streitberger needles at the same points. MEASUREMENTS AND RESULTS: Self-reported questionnaires, 1-week sleep diaries, and 3-day actigraphy were collected at baseline and 1 week after treatment. The Insomnia Severity Index was used as the primary outcome measure. Both groups showed significant improvement compared with the pretreatment baseline. One-way analysis of covariance adjusted for baseline scores showed that there were significantly greater improvements in sleep efficiency by sleep diary and actigraphy in the electroacupuncture group. However, no significant between-group differences were observed in the Insomnia Severity Index and other outcome measures. The proportions of subjects having less than 30 minutes of wake after sleep onset and a sleep efficiency of at least 85% at the posttreatment visit were significantly higher in the electroacupuncture group. All adverse events were mild in severity. CONCLUSION: We found a slight advantage of electroacupuncture over placebo acupuncture in the short-term treatment of primary insomnia. Because of some limitations of the current study, further studies are necessary to verify the effectiveness of acupuncture for insomnia.

Traditional needle acupuncture treatment for insomnia: a systematic review of randomized controlled trials.

OBJECTIVES: Previous reviews regarding traditional needle acupuncture (TNA) treatment for insomnia were limited to English scientific literature. A comprehensive review including Chinese and English literature has therefore been conducted to examine the efficacy of TNA for insomnia. METHODS: We performed systematic review of randomized controlled trials (RCTs) of TNA as intervention for insomnia against placebo, Western medication, and non-treated controls. The methodological quality of the studies was assessed by the modified Jadad score and the acupuncture procedure was appraised by the STRICTA criteria. RESULTS: Twenty RCTs were identified for detailed analysis. Majority of the RCTs concluded that TNA was significantly more effective than benzodiazepines for treating insomnia, with mean effective rates for acupuncture and benzodiazepines being 91% and 75%, respectively. In two more appropriately conducted trials, TNA appeared to be more efficacious in improving sleep than sleep hygiene counseling and sham acupuncture. Standardized and individualized acupuncture had similar effective rates. Despite these positive outcomes, there were methodological shortcomings in the studies reviewed, including imprecise diagnostic procedure, problems with randomization, blinding issues, and insufficient safety data. Hence, the superior efficacy of TNA over other treatments could not be ascertained. CONCLUSION: Since the majority of evidence regarding TNA for insomnia is based on studies with poor-quality research designs, the data, while somewhat promising, do not allow a clear conclusion on the benefits of TNA for insomnia. Moreover, the results support the need for large scale placebo-controlled double-blinded trials.