Structural Properties of Kerogens with Different Maturities.

The thermogenic transformation of kerogen into hydrocarbons accompanies the development of a pore network within the kerogen that serves as gas storage locations both in pore space and surface area for adsorbed gas within the source rock. Therefore, the successful recovery of gas from these rocks depends on the accessible surface area, surface properties, and interconnectivity of the pore system. These parameters can be difficult to determine because of the nanoscale of the structures within the rock. This study seeks to investigate the pore structure, surface heterogeneity, and composition of recovered kerogens isolated from source rocks with progressively increasing thermogenic maturities. Prompt gamma-ray activation analysis (PGAA), nitrogen and methane volumetric gas sorption, and small-angle neutron scattering (SANS) are combined to explore the relationship between the chemical composition, pore structure, surface roughness, surface heterogeneity, and maturity. PGAA results indicate that higher mature kerogens have lower hydrogen/carbon ratio. Nitrogen gas adsorption indicates that the pore volume and accessible specific surface area are higher for more mature kerogens. The methane isosteric heat at different methane uptake in the kerogens is determined by methane isotherms and shows that approximately two types of binding sites are present in low mature kerogens while the binding sites are relatively homogeneous in the most mature kerogen. The hysteresis effect of the structure during the adsorption and desorption process at different CD4 gas pressures are studied. An extended generalized Porod's scattering law method (GPSLM) is further developed here to analyze kerogens with fractal surfaces. This extended GPSLM quantifies the surface heterogeneity of the kerogens with a fractal surface and shows that kerogen with high maturity is chemically more homogeneous, consistent with the results from methane isosteric heat. SANS analysis also suggests a pronounced surface roughness in the more mature kerogens. A microporous region circling around the nanopores, which contributes to high surface roughness and methane storage, is shown to develop with maturity.

Pinworm infections associated with risk of psychiatric disorders-A nationwide cohort study in Taiwan: Pinworm infections and psychiatric disorders.

AIM: This study aimed to investigate the association between males with pinworm infections and the risk of developing psychiatric disorders. METHOD: A total of 2044 enrolled patients, with 511 pinworm subjects and 1533 unexposed subjects (1:3) matched for sex, age and index year, from Taiwan's Longitudinal Health Insurance Database (LHID) from 2000 to 2015, selected from the National Health Insurance Research Database (NHIRD). After adjusting for confounding factors, the Cox regression model was used to compare the risk of developing psychiatric disorders during the 15 years of follow-up. RESULTS: Of all the enrollees, 24 in the pinworm cohort and 18 in the unexposed cohort (343.10 vs 84.96 per 100,000 person-year) developed psychiatric disorders. The Cox regression model revealed that, after adjusting for sex, age, monthly income, urbanization level, geographic region, and comorbidities, the adjusted HR was 4.581 (95% CI: 2.214-9.480, p < .001, p < .001). Pinworm infections were associated with the increased risk in anxiety disorders, depressive disorders, and sleep disorders, respectively. CONCLUSION: Patients who suffered from pinworm infections have a higher risk of developing psychiatric disorders, and this finding should be considered as a timely reminder for the clinicians to provide much more attention for these patients because of their mental health issues.

Investigation of porous materials with large surface heterogeneity using the generalized Porod's scattering law method.

Surface heterogeneity is ubiquitous in both natural and man-made materials, and can significantly influences material properties. However, it is very challenging to noninvasively probe the variation of surface properties in porous materials. Recently, we have proposed a method, i.e., the generalized Porod's scattering law method (GPSLM), to obtain the surface heterogeneity information in bulk porous materials by extending the classic Porod's scattering method. However, it was not clear if the GPSLM can be applied to other more complex materials, such as porous materials with dead pores, i.e., pores that guest fluid molecules cannot access or porous materials whose solid matrix can adsorb small guest molecules. In this paper, we theoretically extend the GPSLM to study those more complex situations. For all five cases with different levels of complexity discussed in this work, the scattering intensity at the Porod's law region always follows a parabolic function of scattering length density (SLD) of the guest fluid. Moreover, the minimum value of the scattering intensity is all related to the surface heterogeneity of the porous materials. The SLD of the guest fluid at which the minimum intensity is reached is always related to the surface-averaged SLD of materials. We also discuss the potential limitations and possible future applications of the GPSLM. As the GPSLM is based on the contrast variation method commonly used for a wide range of materials, such as geological materials, biomaterials, and colloidal suspensions, the theoretical development here is potentially useful for researchers who would like to apply the GPSLM to more complicated materials besides porous materials.

Risk of Psychiatric Morbidity in Psychosexual Disorders in Male Patients: A Nationwide, Cohort Study in Taiwan.

This study aimed to investigate the association between males with psychosexual disorders (PSDs) and the risk of developing psychiatric disorders. A total of 34,972 enrolled patients, with 8,743 subjects who had suffered from PSD and 26,229 controls (1:3) matched for age and index year, from Taiwan's Longitudinal Health Insurance Database (LHID) from 2000 to 2015, selected from the National Health Insurance Research Database (NHIRD). After adjusting all the confounding factors, the multivariate Cox regression model was used to compare the risk of developing psychiatric disorders, between the PSD and non-PSD groups, during the 15 years of follow-up. Of the all enrollees, 1,113 in the PSD cohort and 2,611 in the non-PSD cohort (1,180.96 vs. 954.68 per 100,000 person-year) developed psychiatric disorders. Multivariate Cox regression model survival analysis revealed that, after adjusting for gender, age, monthly income, urbanization level, geographic region, and comorbidities, the adjusted hazard ratio (HR) was 2.448 (95% CI [2.227, 2.633], p < .001). PSD has been associated with the increased risk in anxiety disorders, depressive disorders, bipolar disorders, sleep disorders, and psychotic disorders, respectively. Sexual dysfunctions, paraphilia, and gender identity disorders were associated with the overall psychiatric disorders with adjusted HRs as 1.990 ( p < .001), 11.622 ( p < .001), and 5.472 ( p < .001), respectively. Male patients who suffered from PSD have a higher risk of developing psychiatric disorders, and this finding should be considered as a timely reminder for the clinicians to provide much more attention for these patients because of their mental health issues.

Obstructive Sleep Apnea in Children and Adolescents and the Risk of Major Adverse Cardiovascular Events: A Nationwide Cohort Study in Taiwan.

STUDY OBJECTIVES: This study has investigated the risk of major adverse cardiovascular events (MACEs), including acute myocardial infarction, coronary artery disease, peripheral artery disease, and acute stroke, among children and adolescents (age younger than 20 years) with obstructive sleep apnea (OSA). METHODS: In this study, the population-based National Health Insurance Research Database of Taiwan was used to identify patients in whom OSA had been first diagnosed between 2000 and 2015. Children and adolescents with OSA (n = 6,535) were included with 1:3 ratio by age, sex, and index year of control participants without OSA (n = 19,605). The Cox proportional regression model was used to evaluate the risk of MACEs in this cohort study. RESULTS: After a 15-year follow-up, the incidence rate of MACEs was higher in the OSA cohort when compared with the non-OSA control cohort (15.97 and 8.20 per 100,000 person-years, respectively). After adjusting for covariates, the risk of MACEs among children and adolescents with OSA was still significantly higher (hazard ratio = 2.050; 95% confidence interval = 1.312-3.107; P = .010). No MACEs were found in the children and adolescents with OSA who received continuous airway positive pressure treatment or pharyngeal surgery. CONCLUSIONS: This study found a significantly higher risk of MACEs in children and adolescents with OSA. These findings strongly suggest that clinicians should provide careful follow-up and medical treatment for children and adolescents with OSA.

Risk of Dementia in Adults With ADHD: A Nationwide, Population-Based Cohort Study in Taiwan.

OBJECTIVE: This study aimed to investigate the association between adults with ADHD and the risk of developing dementia. METHOD: Utilizing National Health Insurance Research Database of Taiwan, ADHD patients were identified and compared with age- and gender-matched controls (1:3). RESULTS: Of the study participants, 37 (5.48%) developed dementia compared with 81 (4.0%) in the control group. Cox proportional hazards regression analysis revealed that the study participants were more likely to develop dementia. The crude hazard ratio (HR) is 3.418 (95% confidence interval [CI] = [2.289, 5.106], p < .001), and adjusted HR is 4.008 (95% CI = [2.526, 6.361], p < .001) in risk of developing dementia after adjusted for age, gender, comorbidities, geographical area of residence, urbanization level of residence, and monthly income. CONCLUSION: Adults with ADHD have a 3.4-fold risk of developing dementia, and other large or national data sets should be explored to support the current findings.

Risk of psychiatric disorders in overactive bladder syndrome: a nationwide cohort study in Taiwan.

Population-based cohort study investigating the risk of depression and other psychiatric disorders for patients with overactive bladder (OAB) syndrome is unavailable. This study investigated the subsequent risk of psychiatric disorders among patients with OAB in an Asian population. Using data from the National Health Insurance Research Database of Taiwan, we established a cohort with 811 patients in an exposed group with OAB between January 1, 2000 and December 31, 2000, and a non-exposed group, without OAB, of 2433 patients without OAB matched by age and year of diagnosis. The occurrence of psychiatric disorders and Cox regression model measured adjusted HRs (aHR) were monitored until the end of 2013. The overall incidence of psychiatric disorders was 41.7% higher in the exposed group with OAB than in the non-exposed group without OAB (14.2% vs 10.1%, p<0.001), with an aHR of 1.34 (95% CI 1.12 to 1.80, p<0.001) for the OAB cohort. OAB was associated with the increased risk of dementia, anxiety, depressive, sleep, and psychotic disorders, with aHRs as 1.53 (p=0.040), 1.61 (p<0.001), 2.10 (p<0.001), 1.43 (p<0.001), and 2.49 (p=0.002), respectively. The risk of psychiatric disorders, including depression and anxiety, is significantly higher in patients with OAB than in those without OAB. Evaluation of psychiatric status in patients with OAB is strongly recommended.

Increased Risk of Psychiatric Disorders in Allergic Diseases: A Nationwide, Population-Based, Cohort Study.

BACKGROUND/OBJECTIVE: Allergic diseases, such as bronchial asthma, allergic rhinitis, atopic dermatitis, and psychiatric disorders, are major health issues. There have been reports that allergic diseases were associated with depression or anxiety disorders. This study aimed to investigate the association between these allergic diseases and the risk of developing overall psychiatric disorders in patients from Taiwan. METHODS: This cohort study used the database of the Taiwan National Health Insurance Program. A total of 186,588 enrolled patients, with 46,647 study subjects who had suffered from allergic diseases, and 139,941 controls matched for sex and age, from the Longitudinal Health Insurance Dataset of 2000-2015, were selected from a sub-dataset of the National Health Insurance Research Database. Fine and Gray's competing risk model analysis was used to explore the hazard ratio (HR), and 95% confidence interval, for the risk of allergic diseases being associated with the risk of developing psychiatric disorders during the 15 years of follow-up. RESULTS: Of the study subjects, 5,038 (10.8%) developed psychiatric disorders when compared to 9,376 (6.7%) in the control group, with significant difference (p < 0.001). Fine and Gray's competing risk model analysis revealed that the adjusted HR was 1.659 (95% CI = 1.602-1.717, p < 0.001). In this study, we found that the groups of atopic dermatitis alone and the allergic rhinitis + atopic dermatitis were associated with a lower risk of psychiatric disorders, but all the other four groups, such as bronchial asthma alone, allergic rhinitis alone, bronchial asthma + allergic rhinitis, bronchial asthma + atopic dermatitis, and the combination of all these three allergic diseases, were associated with a higher risk of psychiatric disorders. CONCLUSION: Allergic diseases are therefore associated with a 1.66-fold increased hazard of psychiatric disorders in Taiwan.

Forensic Evaluations for Offenders With Dementia in Taiwan's Criminal Courts.

Dementia is an increasing world-wide health problem, and the association between dementia and adjudication of crimes has rarely been studied. The data in this study are described and analyzed by gender, psychiatric diagnosis, type of crime, and the acceptance rate by the courts of opinions tendered by forensic psychiatric examiners. The source data are derived from the databank of the Judicial Yuan (Judicial Department) of the Republic of China Law and Regulations Retrieval System. There was a male predominance of 85.1 percent. Larceny (42.6%) was the most frequent crime. There was also a high judicial acceptance rate of 91.5 percent of the professional opinions received from forensic psychiatric evaluators who examined defendants at the request of the courts. Psychiatrists play an important role in providing their professional opinions for the Taiwanese courts with regard to adjudication of evaluees with dementia. Most courts accepted psychiatrists' professional opinions about offenders with dementia, and the rate of acceptance was reflected in the judicial rulings of criminal responsibility.

Anti-herpetic Medications and Reduced Risk of Dementia in Patients with Herpes Simplex Virus Infections-a Nationwide, Population-Based Cohort Study in Taiwan.

This retrospective cohort study is to investigate the association between herpes simplex virus (HSV) infections and dementia, and the effects of anti-herpetic medications on the risk involved, using Taiwan's National Health Insurance Research Database (NHIRD). We enrolled a total of 33,448 subjects, and identified 8362 with newly diagnosed HSV infections and 25,086 randomly selected sex- and age-matched controls without HSV infections in a ratio of 1:3, selected from January 1, to December 31, 2000. A multivariable Cox proportional hazards regression model was used to evaluate the risk of developing dementia in the HSV cohort. This analysis revealed an adjusted hazard ratio of 2.564 (95% CI: 2.351-2.795, P < 0.001) for the development of dementia in the HSV-infected cohort relative to the non-HSV cohort. Thus, patients with HSV infections may have a 2.56-fold increased risk of developing dementia. A risk reduction of dementia development in patients affected by HSV infections was found upon treatment with anti-herpetic medications (adjusted HR = 0.092 [95% CI 0.079-0.108], P < 0.001). The usage of anti-herpetic medications in the treatment of HSV infections was associated with a decreased risk of dementia. These findings could be a signal to clinicians caring for patients with HSV infections. Further research is, therefore, necessary to explore the underlying mechanism(s) of these associations.

A non-invasive method to directly quantify surface heterogeneity of porous materials.

It is extremely challenging to measure the variation of pore surface properties in complex porous systems even though many porous materials have widely differing pore surface properties at microscopic levels. The surface heterogeneity results in different adsorption/desorption behaviors and storage capacity of guest molecules in pores. Built upon the conventional Porod's law scattering theory applicable mainly to porous materials with relatively homogeneous matrices, here we develop a generalized Porod's scattering law method (GPSLM) to study heterogeneous porous materials and directly obtain the variation of scattering length density (SLD) of pore surfaces. As SLD is a function of the chemical formula and density of the matrix, the non-invasive GPSLM provides a way to probe surface compositional heterogeneity, and can be applied to a wide range of heterogeneous materials especially, but not limited to, porous media and colloids, using either neutron or X-ray scattering techniques.

Fibromyalgia and Risk of Dementia-A Nationwide, Population-Based, Cohort Study.

BACKGROUND: Fibromyalgia is a syndrome of chronic pain and other symptoms and is associated with patient discomfort and other diseases. This nationwide matched-cohort population-based study aimed to investigate the association between fibromyalgia and the risk of developing dementia, and to clarify the association between fibromyalgia and dementia. MATERIALS AND METHODS: A total of 41,612 patients of age ≥50 years with newly diagnosed fibromyalgia between January 1, and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 124,836 controls matched for sex and age. After adjusting for any confounding factors, Fine and Gray competing risk analysis was used to compare the risk of developing dementia during the 10 years of follow-up. RESULTS: Of the study subjects, 1,704 from 41,612 fibromyalgia patients (21.23 per 1,000 person-years) developed dementia when compared to 4,419 from 124,836 controls (18.94 per 1,000 person-years). Fine and Gray competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio: 2.29, 95% CI: 2.16-2.42; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities the hazard ratio was 2.77 (95% CI: 2.61-2.95, P < 0.001). Fibromyalgia was associated with increased risk of all types of dementia in this study. CONCLUSIONS: The study subjects with fibromyalgia had a 2.77-fold risk of dementia in comparison to the control group. Therefore, further studies are needed to elucidate the underlying mechanisms of the association between fibromyalgia and the risk of dementia.

Cognitive enhancers associated with decreased risk of injury in patients with dementia: a nationwide cohort study in Taiwan.

This study aimed to investigate the associations among dementia, psychotropic medications and the risk of overall injuries. In this nationwide matched cohort study, a total of 144 008 enrolled patients ≥age of 50, with 36 002 study subjects who suffered from dementia and 108 006 controls matched for sex and age, from the Inpatient Dataset, for the period 2000-2010 in Taiwan were selected from the National Health Insurance Research Database, according to International Classification of Diseases, 9th Revision, Clinical Modification. When adjusting for the confounding factors, a Cox proportional hazards analysis was used to compare the risk of developing psychiatric disorders during the 10 years of follow-up. Of the study subjects, 6701 (18.61%) suffered injury when compared with 20 919 (19.37%) in the control group. The Cox regression analysis revealed that the study subjects were more likely to develop an injury (HR: 2.294, 95% CI=2.229 to 2.361, P<0.001) after adjusting for sex, age, monthly income, urbanization level, geographic region, and comorbidities. Psychotropic medications in the subjects with dementia were associated with the risk of injury (adjusted HR=0.217, 95% CI: 0.206 to 0.228, P<0.001). Cognitive enhancers, including acetylcholinesterase inhibitors and memantine, were associated with the risk of injury in the study subjects after being adjusted for all comorbidities and medications (adjusted HR=0.712(95% CI=0.512 to 0.925, P<0.01)). In conclusion, patients who suffered dementia had a higher risk of developing injury, and the cognitive enhancers were associated with the decreased risk of injury.

Magnesium oxide use and reduced risk of dementia: a retrospective, nationwide cohort study in Taiwan.

OBJECTIVE: Dietary magnesium may be associated with a lower risk of dementia; however, the impact of magnesium oxide (MgO), a common laxative, on dementia has yet to be elucidated. This study aimed to investigate the association between the usage of MgO and the risk of developing dementia. METHODS: We used a dataset from the National Health Research Institute Database (NHRID) of Taiwan containing one million randomly sampled subjects to identify patients aged ≥50 years with no history of MgO usage. A total of 1547 patients who had used MgO were enrolled, along with 4641 controls who had not used the MgO propensity score matched by age, gender and comorbidity, at a ratio of 1:3. After adjusting for confounding risk factors, a Cox proportional hazards model was used to compare the risk of developing dementia during a 10 year follow-up period. RESULTS: Of the enrolled patients, 44 (2.84%) developed dementia, when compared to 199 (4.28%) in the control group. The Cox proportional hazards regression analysis revealed that the patients who had used MgO were less likely to develop dementia with a crude hazard ratio of 0.617 (95% CI, 0.445-0.856, p = .004). After adjusting for age, gender, comorbidity, geographical area and urbanization level of residence, and monthly income, the adjusted hazard ratio was 0.517 (95% CI, 0.412-0.793, p = .001). CONCLUSIONS: The patients who used MgO had a decreased risk of developing dementia. Further studies on the effects of MgO in reducing the risk of dementia are therefore warranted.

Quasi-Two-Dimensional Phase Transition of Methane Adsorbed in Cylindrical Silica Mesopores.

Using Monte Carlo and molecular dynamics simulations, we examine the adsorption of methane in cylindrical silica mesopores in an effort to understand a possible phase transition of adsorbed methane in MCM-41 and SBA-15 silica that was previously identified by an unexpected increase in the adsorbed fluid density following capillary condensation, as measured by small-angle neutron scattering (SANS) [Chiang, W-S., et al., Langmuir 2016, 32, 8849]. Our initial simulation results identify a roughly 10 % increase in the density of the liquidlike adsorbed phase for either an isotherm with increasing pressure or an isobar with decreasing temperature and that this densification is associated with a local maximum in the isosteric enthalpy of adsorption. Subsequent analysis of the simulated fluid, via computation of bond-orientational order parameters of specific annular layers of the adsorbed fluid, showed that the layers undergo an ordering transition from a disordered, amorphous state to one with two-dimensional hexagonal structure. Furthermore, this two-dimensional restructuring of the fluid occurs at the same thermodynamic state points as the aforementioned densification and local maximum in the isosteric enthalpy of adsorption. We thus conclude that the densification of the fluid is the result of structural reorganization, which is signaled by the maximum in the isosteric enthalpy. Owing to the qualitative similarity of the structural transitions in the simulated and experimental methane fluids, we propose this hexagonal reorganization as a plausible explanation of the densification observed in SANS measurements. Lastly, we speculate how this structural transition may impact the transport properties of the adsorbed fluid.

Risk of psychiatric disorders in Guillain-Barre syndrome: A nationwide, population-based, cohort study.

BACKGROUND: Guillain-Barre syndrome (GBS) is a rare immune-related neurological disorder with high mortality and morbidity, but the comorbid psychiatric disorders garnered little attention in the GBS patients. This study aimed to investigate the association between GBS and the risk of developing psychiatric disorders. METHODS: A total of 18,192 enrolled patients, with 4548 study subjects who had suffered GBS, and 13,644 controls matched for gender and age, from the Inpatient Dataset of 2000-2013 in Taiwan, and selected from the National Health Insurance Research Database (NHIRD). After adjusting for confounding factors, Cox proportional hazards analysis was used to compare the risk of developing psychiatric disorders during the 13years of follow-up. RESULTS: Of the study subjects, 471 (10.35%) developed psychiatric disorders when compared to 1023 (7.50%) in the control group. Fine and Gray's competing risk model analysis revealed that the study subjects were more likely to develop psychiatric disorders (crude hazard ratio [HR]: 4.281 (95% CI=3.819-4.798, p<0.001). After adjusting for gender, age, monthly income, urbanization level, geographic region, and comorbidities, the adjusted HR was 4.320 (95% CI=3.852-4.842, p<0.001). Dementia, depressive disorders, sleep disorders, and psychotic disorders predominate in these psychiatric disorders. Mechanical ventilation and hemodialysis are associated with a lower risk of dementia when compared to the control groups. CONCLUSIONS: Patients who suffered from GBS had a higher risk of developing psychiatric disorders, and this finding should act as a reminder to the clinicians that a regular psychiatric follow-up might well be needed for those patients.

The risk of injury in adults with attention-deficit hyperactivity disorder: A nationwide, matched-cohort, population-based study in Taiwan.

BACKGROUND: Few studies have investigated the risk of injuries associated with adults with attention-deficit hyperactivity disorder (ADHD), even though several studies have suggested a higher risk of injury in children and adolescents with ADHD. AIMS: To investigate the risk of injury in adults with ADHD. METHODS AND PROCEDURES: We included 665 adults with ADHD from January 1, to December 31, 2000, and 1995 sex-, age- and index day-matched controls without ADHD from the Longitudinal Health Insurance Database (LHID) subset of the National Health Insurance Research Database in Taiwan. The Cox proportional hazard models were used to analyze the associations between the relevant demographics, and the psychiatric comorbidities and the risk of injury. OUTCOMES AND RESULTS: The patients with ADHD had a 143% increased risk of overall injuries than the controls after considering all the confounding factors. In addition, the use of methylphenidate was associated with a 22.6% decrease in the risk of injuries in the patients with ADHD. CONCLUSIONS AND IMPLICATIONS: Our findings strongly support that adults with ADHD are at an increased risk of injury, and imply that methylphenidate therapy may attenuate this risk.

Headaches and Risk of Dementia.

BACKGROUND: Primary headaches include migraines, tension-type headaches and other primary headache syndromes. Migraines and tension-type headaches are associated with patient discomfort and other diseases. This study aimed to investigate the association between primary headaches and the risk of developing dementia, and to clarify the association between different types of headaches and dementia. MATERIALS AND METHODS: We conducted a nationwide matched cohort population-based study. A total of 3,620 patients with newly diagnosed primary headaches, including migraines and tension-type headaches, between January 1 and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 10,860 controls matched for sex and age. After adjusting for confounding factors, Fine and Gray׳s competing risk analysis was used to compare the risk of developing dementia during 10 years of follow-up. RESULTS: Of the study subjects, 170 (4.70 %) developed dementia compared with 433 (3.99%) of the controls. Fine and Gray׳s competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio = 2.057; 95% CI: 1.718-2.462; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities, the hazard ratio for dementia was 2.048 (95% CI: 1.705-2.461, P < 0.001). Migraines and tension-type headaches were associated with nonvascular dementia but not vascular dementia. CONCLUSIONS: The patients with headaches had a 105% increased risk of dementia. Further studies are needed to elucidate the underlying mechanisms.

Are Chronic Periodontitis and Gingivitis Associated with Dementia? A Nationwide, Retrospective, Matched-Cohort Study in Taiwan.

BACKGROUND: Chronic periodontitis and gingivitis are associated with various diseases; however, their impact on dementia is yet to be elucidated. This study is aimed at investigating the association between chronic periodontitis and gingivitis, and the risk of developing dementia. METHODS: A total of 2,207 patients, with newly diagnosed chronic periodontitis and gingivitis between January 1, 2000 and December 31, 2000, were selected from the National Health Insurance Research Database of Taiwan, along with 6,621 controls matched for sex and age. After adjusting for confounding factors, Cox proportional hazards analysis was used to compare the risk of developing dementia during the 10-year follow-up period. RESULTS: Of the study subjects, 25 (1.13%) developed dementia compared to 61 (0.92%) in the control group. Cox proportional hazards regression analysis revealed that the study subjects were more likely to develop dementia (hazard ratio (HR) 2.085, 95% CI 1.552-4.156, p < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region, and comorbidities, the HR for dementia was 2.54 (95% CI 1.297-3.352, p = 0.002). CONCLUSIONS: Patients with chronic periodontitis and gingivitis have a higher risk of developing dementia. However, further studies on other large or national data sets are required to support the current findings.

Forensic Psychiatric Evaluation for Military Absenteeism in Taiwan.

The relationship between military absenteeism and mental health problems has been noted; however, factors affecting military absenteeism by enlisted personnel have not been studied systematically. In a medical center in Taiwan, we performed a chart review of 26 forensic psychiatric evaluations of enlisted personnel who were absent without leave (AWOL) or deserted their service from 1994 to 2014. The findings showed that many of these recruits had a lower level of education (50.00% had just nine years of education), intellectual disability (46.15%), depressive disorders (30.76%), and suicidal ideation (53.85%). Depressive disorder was overrepresented in comparison with findings in a previous study. Further study is needed to confirm whether psychiatric screening before service enlistment and early psychiatric intervention for service members with mental illness or emotional disturbance could help in the prevention of desertion or going AWOL.