Constructing prediction models and analyzing factors in suicidal ideation using machine learning, focusing on the older population.

Suicide among the older population is a significant public health concern in South Korea. As the older individuals have long considered suicide before committing suicide trials, it is important to analyze the suicidal ideation that precedes the suicide attempt for intervention. In this study, six machine learning algorithms were employed to construct a predictive model for suicidal thinking and identify key variables. A traditional logistic regression analysis was supplementarily conducted to test the robustness of the results of machine learning. All analyses were conducted using a hierarchical approach to compare the model fit of each model in both machine learning and logistic regression. Three models were established for analysis. In Model 1, socioeconomic, residential, and health behavioral factors were incorporated. Model 2 expanded upon Model 1 by integrating physical health status, and Model 3 further incorporated mental health conditions. The results indicated that the gradient boosting algorithm outperformed the other machine learning techniques. Furthermore, the household income quintile was the most important feature in Model 1, followed by subjective health status, oral health, and exercise ability in Model 2, and anxiety and depression in Model 3. These results correspond to those of the hierarchical logistic regression. Notably, economic and residential vulnerabilities are significant factors in the mental health of the older population with higher instances of suicidal thoughts. This hierarchical approach could reveal the potential target population for suicide interventions.

Association between initial continuity of care status and diabetes-related health outcomes in older patients with type 2 diabetes mellitus: A nationwide retrospective cohort study in South Korea.

BACKGROUND AND AIM: Timely and continuous care is necessary for patients with diabetes to prevent hospitalization and complications. This study investigated the association between initial Continuity of Care Index (COCI) status after diagnosis of type 2 diabetes mellitus (T2DM) and short- and long-term diabetes-related health outcomes. METHODS: It targeted elderly patients aged 60 years and above diagnosed with T2DM and used the National Health Insurance Service Senior cohort data from 2008 to 2019. The outcome measures were diabetic avoidable hospitalization and diabetic complication incidence for a five-year period. The main independent variable was the first-year COCI status after T2DM diagnosis. Survival analyses were performed using the Cox proportional hazards model. RESULTS: Participants with a good COCI status within the first year of being diagnosed with T2DM experienced a reduced risk of diabetes-induced avoidable hospitalization (five years: Hazard ratio (HR) 0.39, 95 % Confidence interval (CI) 0.27-0.57; overall period: HR 0.56, 95 % CI 0.43-0.72) and diabetic complications (five years: HR 0.74, 95 % CI 0.68-0.80; overall period: HR 0.77, 95 % CI 0.71-0.82). CONCLUSIONS: In the short- and long-term, there is a need for early management and improved healthcare accessibility of diabetes to prevent diabetes-avoidable hospitalization and diabetes-related complications.

Examining the factors associated with inpatients' perception of overtreatment in Korea: a cross-sectional study.

BACKGROUND: Patients' perception of receiving overtreatment can cause distrust in medical services. Unlike outpatients, inpatients are highly likely to receive many medical services without fully understanding their medical situation. This information asymmetry could prompt inpatients to perceive treatment as excessive. This study tested the hypothesis that there are systematic patterns in inpatients' perceptions of overtreatment. METHODS: We examined determinant factors of inpatients' perception of overtreatment in a cross-sectional design that used data from the 2017 Korean Health Panel (KHP), a nationally representative survey. For sensitivity analysis, the concept of overtreatment was analyzed by dividing it into a broad meaning (any overtreatment) and a narrow meaning (strict overtreatment). We performed chi-square for descriptive statistics, and multivariate logistic regression with sampling weights employing Andersen's behavioral model. RESULTS: There were 1,742 inpatients from the KHP data set that were included in the analysis. Among them, 347 (19.9%) reported any overtreatment and 77 (4.42%) reported strict overtreatment. Furthermore, we found that the inpatient's perception of overtreatment was associated with gender, marital status, income level, chronic disease, subjective health status, health recovery, and general tertiary hospital. CONCLUSION: Medical institutions should understand factors that contribute to inpatients' perception of overtreatment to mitigate patients' complaints due to information asymmetry. Moreover, based on the result of this study, government agencies, such as the Health Insurance Review and Assessment Service, should create policy-based controls and evaluate overtreatment behavior of the medical providers and intervene in the miscommunication between patients and providers.

Which indicator should be used? A comparison between the incidence and intensity of catastrophic health expenditure: using difference-in-difference analysis.

BACKGROUND: Catastrophic health expenditure (CHE) represents out-of-pocket payment as a share of household income. Most previous studies have focused on incidence aspects when assessing health policy effects. However, because CHE incidence is a binary variable, the effect of the health policy could not accurately be evaluated. On the contrary, the intensity of CHE is a continuous variable that can yield completely different results from previous studies. This study reassesses the coverage expansion plan for four serious diseases using the intensity of CHE in Korea. METHODS: We used the Korea Health Panel Study from 2013 to 2015 to conduct the analysis. The study population is households with chronic diseases patients. We divided the population into two groups: the policy beneficiary group, i.e., households with a patient of any of the four serious diseases, and the non-beneficiary group. A difference-in-difference model was employed to compare the variation in the intensity and incidence of CHE between the two groups. We defined the incidence of CHE as when the ratio of out-of-pocket medical expenses to household income is more than a threshold of 10%, and the intensity of CHE is the height of the ratio subtracting the threshold 10%. RESULTS: The increased rate of CHE intensity in households with four serious diseases was lower than that in households with other chronic diseases. The interaction term, which represents the effect of the policy, has a significant impact on the intensity but not on the incidence of CHE. CONCLUSIONS: CHE indicators should be applied differently according to the purpose of policy evaluation. The incidence of CHE should be used as the final achievement indicator, and the intensity of CHE should be used as the process indicator. Furthermore, because CHE has an inherent characteristic that is measured by the ratio of household income to medical expenses, to lower this, a differential out-of-pocket maximum policy for each income class is more appropriate than a policy for strengthening the coverage for specific diseases.

How public and private health insurance coverage mitigates catastrophic health expenditures in Republic of Korea.

BACKGROUND: The private health insurance (PHI) market in Republic of Korea has instituted indemnity insurance plans that provide partial reimbursements for some medical services or costs that are not covered by the National Health Insurance (NHI). To date, no study has estimated the extent to which PHI coverage lowers the economic burden of households' access to health care. The current study aims to evaluate the design of Korea's PHI system in terms of coverage using a catastrophic health expenditure (CHE) indicator and compare it with NHI. METHODS: This study determined the difference between the number of households that were subscribed to PHI and those that received reimbursements from PHI. Additionally, it compared the effects of reduced CHE by NHI benefits with PHI reimbursements. Furthermore, it compared PHI reimbursements based on income class. Finally, it analyzed the contribution of NHI and PHI to CHE reduction through a two-part model with hierarchical regression. RESULTS: The results indicated that of the 5644 households examined, 3769 subscribed to PHI, but only 246 households received reimbursements. Notably, NHI reduced CHE incidence by 15.17%, whereas PHI only reduced CHE by 1.22%. The NHI scheme indicated reduced inequality as it provided more benefits to the low-income class for their used medical services, whereas PHI paid more reimbursements to the high-income class. Accordingly, NHI coverage has protected households from CHE and improved equality to some extent; however, PHI coverage has had a relatively low effect on relieving CHE and has increased inequality. CONCLUSIONS: The indemnity health insurance plans of PHI companies in Korea only cover partial medical costs or services, and so, most patients do not receive reimbursements. Thus, Korea's PHI system needs to improve to provide benefits to patients more generously and alleviate their financial burden.

Optimizing intramedullary entry location on the proximal humerus based on variations of neck-shaft angle.

BACKGROUND: The purpose of this study was to define the relationship between the humeral neck-shaft angle (NSA) and variations in the ideal entry portal aligned with the long axis of the intramedullary canal of the proximal humerus. METHODS: Three-dimensional images of 36 cadaveric humeri with various NSAs were reconstructed by a computerized surgical simulation program. The anteroposterior, mediolateral, and linear distances between a line from the center of the proximal medullary canal to the bicipital groove were measured. Differences among humeri with various NSAs were analyzed. RESULTS: The intramedullary axis line was located a mean of 9 ± 2 mm posteriorly and 11 ± 3 mm medially from the bicipital groove. The axis line was 9 ± 2 mm posterior and 11 ± 2 mm medial with a standard NSA. The axis line in humeri with a varus NSA was 8 ± 2 mm posteriorly and 9 ± 2 mm medially, whereas the axis line was 10 ± 3 mm posteriorly and 14 ± 3 mm medially with a valgus NSA. The differences in the mediolateral distances between the groups were significant (P < .00009). CONCLUSION: Care should be taken in choosing the entry portal position in humeri with various NSAs as the entry portal position differs according to the NSA. It is recommended that the location of the entry portal be moved toward the center of the humeral head to align with the centerline of the intramedullary canal in humeri with a valgus NSA in particular.

Effects of Trunk Stabilization Exercises on Different Support Surfaces on the Cross-sectional Area of the Trunk Muscles and Balance Ability.

[Purpose] The purpose of this study was to examine the effects on stroke patients of trunk stabilization exercise on different support surfaces. [Subjects and Methods] Sixteen stroke patients with onset of stroke six months earlier or longer were randomly and equally assigned to group I (exercise performed on a stable support surface) and group II (exercise performed on an unstable support surface). The two groups conducted the trunk stabilization exercises on the respective support surfaces, in addition to existing rehabilitation exercises five times per week for 12 weeks. Changes in the cross-sectional area (CSA) of the muscles were examined using computed tomography (CT), and changes in the balance ability were assessed using a measuring system and the trunk impairment scale (TIS). [Results] In group I, there was a significant increase in the CSA of the mulifidus muscle on the side contralateral to the brain lesion and in the paravertebral and multifidus muscles on the side ipsilateral to the brain lesion. In group II, there was a significant increase in the CSA of the paravertebral and multifidus muscles on the side contralateral to the brain lesion and on the side ipsilateral to the brain lesion. In terms of changes in balance ability, the sway path (SP) and TIS significantly improved in group I, and the SP, sway area (SA), and TIS significantly improved in group II . [Conclusion] Exercise on the unstable support surface enhanced the size of the cross-sectional area of the trunk muscles and balance ability significantly more than exercise on the stable support surface.

Cells transformed by PLC-gamma 1 overexpression are highly sensitive to clostridium difficile toxin A-induced apoptosis and mitotic inhibition.

Phospholipase C-γl (PLC-γl) expression is associated with cellular transformation. Notably, PLC-gamma is up-regulated in colorectal cancer tissue and breast carcinoma. Because exotoxins released by Clostridium botulinum have been shown to induce apoptosis and promote growth arrest in various cancer cell lines, we examined here the potential of Clostridium difficile toxin A to selectively induce apoptosis in cells transformed by PLC-γl overexpression. We found that PLC-γl-transformed cells, but not vectortransformed (control) cells, were highly sensitive to C. difficile toxin A-induced apoptosis and mitotic inhibition. Moreover, expression of the proapoptotic Bcl2 family member, Bim, and activation of caspase-3 were significantly up-regulated by toxin A in PLC-γl-transformed cells. Toxin A-induced cell rounding and paxillin dephosphorylation were also significantly higher in PLC-γl-transformed cells than in control cells. These findings suggest that C. difficile toxin A may have potential as an anticancer agent against colorectal cancers and breast carcinomas in which PLC-γl is highly up-regulated.

In vivo strain analysis of the intact supraspinatus tendon by ultrasound speckles tracking imaging.

Limited data exist regarding why delaminated tears occur within the rotator cuff tendon, and no general agreement exists on how to handle this complicated tear. To analyze in vivo intratendinous strain of the supraspinatus tendon, the superficial, middle, and deep regions were marked with speckles using 2D speckle tracking echocardiography (2D STE) of 15 shoulders. The displacement and the strain of each speckle during isotonic and isometric shoulder motion were evaluated. Significantly different displacement and strains in the tendon were found between isometric and isotonic shoulder motions. In isometric motion, the average longitudinal displacement of the speckle at the superficial region (1.66 mm) was larger than at the deep region (0.61 mm), and the average peak strain at the superficial region (17.03%) was also higher than that at the deep region (3.42%). Conversely, in isotonic motion, the average longitudinal displacement of the speckle at the superficial region (0.70 mm) was less than that at the deep region (1.61 mm), and the average peak strain at the superficial region (4.73%) was also lower than that at the deep region (15.69%). A different strain was found between the superficial and deep regions within the intact live supraspinatus tendon. The strain and displacement patterns vary according to isometric versus isotonic shoulder motions. On the basis of our observations, we suggest that the delaminated tear of the rotator cuff tendon must be repaired separately layer by layer to resist the inhomogeneous strain after the repair.

An Aneurysmal Dilatation of Cervical Intramedullary Arteriovenous Malformation: Case Report

A 14-year-old girl presenting with sudden onset of headache, neck pain, and quadriparesis was found to have a vascular lesion in the upper cervical cord(C2-C4) by the initial MRI examination. Vertebral angiography revealed a high-flow arteriovenous malformation which opacified rapidly and drained early. It was a direct spinal arteriovenous fistular consisted of a large aneurysmal dilatation 4x2.2x2.2 cm3 at the junction of a feeding artery and a draining vein. Superior anterior spinal artery and a mid-cervical radicular artery formed a common trunk to feed the lesion that drained entirely superiorly to the posterior fossa through a dilated draining vein. The intramedullary lesion was removed completely after surgical ligation of the feeding artery and draining vein through a posterior approach and myelotomy. She improved to the point of being able to walk alone and attended school one year after operation with acceptable posterior column signs. Spinal cord arteriovenous malformations are traditionally classified into three major categories:Type I, II, III. Our case seemed to fit to the new type:Type IV, direct spinal arteriovenous fistula, proposed by Heros(JNS 64:134-139, 1986).

Effects of Experimental Focal Ischemia of PV- and Calbindin-Immunoreactive Neuron of Rat Neocortex

To understand the changes in expression of calcium binding proteins(CaBP) during the experimental focal ischemia, expression of two kinds of CaBP, paralvumin(PV) and calbindin D-28K(Calbindin), immunocytochemically, and activities of cytochrome oxidase(CO) and acetylcholinesterase(AchE), histochemically, in focal ischemic brain of the rat were investigated. Two groups of focal ischemic infarction were produced in Sprague Dawley rats(200-350 mg):Group I, Clip compression of left middle cerebral artery(MCA) for 5-10 mins and release;Group II, Electric coagulation of left MCA for 2-24 hrs. In the group I, CO activity and PV- and Calbindin-immunoreactivity(IR) were decreased in the left MCA territory, and decreased in number of PV- and Calbindin-IR neurons and degree of IR, but AchE activity was nearly same as that of control cortex. In the group II, decrease of CO and AchE activities, and marked increase of PV- and Calbindin IRs were noted on neuropil in the layers I through VI of ischemic region. Characteristically pyramidal cells, which did not express the both CaBPs in the control cortex, of layer V of ischemic cortex showed PV- and Calbindin Irs in the cell body and apical dendrite. These findings suggest that 1) PV- and Calbindin-IR neurons, mainly non-pyramidal cells, are more vulnerable than pyramidal cell to ischemic injury, 2) CaBP may have some roles in hypoxic neuronal injury, and 3) PV and Calbindin-immunocytochemistry can be used as useful technique in evaluation of experimental ischemia.

Transcranial Doppler Measurement of Intracraial Arterial Flow Velocity in Subarachnoid Hemorrhage

The velocity of blood flow through the middle cerebral arteries was measured by transcranial Doppler sonography in 18 patients with aneurysmal subarachnoid hemorrhage. The velocity became greater from 4th day after the hemorrhage, reached a plateau on 6th-11th day and declined thereafter. 2) In the cases of laterally localized aneurysms, the velocity through the arteries ipsilateral to the aneurysm was significantly greater than that through the arteries contralateral to the aneurysm. 3) The velocity through the arteries of the patients who showed thick subarachnoid clots on CT scan within 3 days after the hemorrhage was significantly greater than that of the patients who showed thin subarachnoid clots. 4) The maximum mean velocity in the patients with delayed ischemic deficits(DID) was greater than that in the patients without DID. The results suggest that the transcranial Doppler monitering is helpful to detect early vasospasm.

Cranial Metastasis of Hepatocellular Carcinoma: Report of Three Cases

The authors describe three cases of hepatocellular carcinoma presenting with the initial manifestation of an intracranial lesion without primary hepatic symptoms and signs. The only clue of hepatic dysfuntion was mild elevation of the SGOT, SGPT, AIK-Pase and hepatomegaly. The diagnosis could not be made until operation. All three cases of hepatoma had metastasis to cranium. The literauture of hepatoma with cranial metastasis is reviewed.

Cranial Metastasis of Hepatocellular Carcinoma: Report of Three Cases

The authors describe three cases of hepatocellular carcinoma presenting with the initial manifestation of an intracranial lesion without primary hepatic symptoms and signs. The only clue of hepatic dysfuntion was mild elevation of the SGOT, SGPT, AIK-Pase and hepatomegaly. The diagnosis could not be made until operation. All three cases of hepatoma had metastasis to cranium. The literauture of hepatoma with cranial metastasis is reviewed.

Traumatic Aneurysms Developing During Aneurysm Surgery

We present two cases of traumatic aneurysms developing during aneurysmal surgery. The aneurysms were clipped without difficulty in both anterior communicating aneurysmal cases. To prevent the vasospasm, bypervolemic theraphy was begun and hypertension was induced postoperatively. The postoperative rebleeding occured within two weeks after initial aneurymal clipping in both cases. New aneursms developed near the clipped anterior communicating aneruysms ; A1 in one case, A2 in the other case. Minor arterial injury was considered to be the main cause of theses new aneurysmal formation and the hemodynamic stress induced by hypertension and hypervolemic therapy might contribute to the development of new aneurysms.

Traumatic Aneurysms Developing During Aneurysm Surgery

We present two cases of traumatic aneurysms developing during aneurysmal surgery. The aneurysms were clipped without difficulty in both anterior communicating aneurysmal cases. To prevent the vasospasm, bypervolemic theraphy was begun and hypertension was induced postoperatively. The postoperative rebleeding occured within two weeks after initial aneurymal clipping in both cases. New aneursms developed near the clipped anterior communicating aneruysms ; A1 in one case, A2 in the other case. Minor arterial injury was considered to be the main cause of theses new aneurysmal formation and the hemodynamic stress induced by hypertension and hypervolemic therapy might contribute to the development of new aneurysms.

Common antigenic determinants on human tumors detected by anti-fetal brain and anti-neuroblastoma monoclonal antibodies / 대한면역학회지

No abstract available.

Pressor Effect of Intracerebroventricular Diphenhydramine and Ranitidine in Rabbits

This study was undertaken to observe the effects of centrally administred antihistamines on the blood pressure. Diphenhydramine(DPH), a H1-receptor antagonist, and ranitidine(RAN), a H2-receptor antagonist were administered intracerebroventricularly(icv) on urethane-anesthetized rabbits. 1) Both DPH and RAN administered intraccebroventricularly increased blood pressure, however the intravenous(iv) adminstration of them did not affect blood pressure. The pressor response to icv DPH was dose-dependent, but that to icv RAN was not. 2) The pressor response to icv DPH(1mg) was either markedly attenuated or reversed to depressor response by the pretreatment with icv phentolamine(250,500ug), and iv chlorisondamine(0.1, 1mg/Kg) and iv phenoxybenzamine(1mg/Kg). In cord-sectioned rabbtis, icv RAN) 1mg) did not produce pressor response. 3) The pressor responsr to icv RAN(1mg) was not affected by the pretreatment with icv phentolamine(500ug), iv chlorisondamin(1mg/Kg) and iv phenoxybenzamine(1mg/Kg), and iv phenoxybenzamine(1mg/Kg). RAN also producted pressor response in cordsectioned rabbits. These results suggest that the pressor response to icv DPH is elecited by increasing peripheral sympathetic tone via the stimulation of central alpha-adrenoreceptors and the pressor response to icv RAN is produced by releasing some humoral facotr which can increase blood pressure.

The Status of Central Nervous System Tumors in Chonnam and Chonbuk Provinces

The authors analized statistically 635 cases of pathologically confirmed central nervous system tumors in the Chonnam and Chonbuk provinces from 1987 to 1989. The results were as follows ; 1) Of the 635 cases, 327 cases(51.5%) were male and 308 cases(48.5%) were female. 2) Intracranial tumors were 518 cases(81.6%), spine and intraspinal tumors 94(14.8%), scalp and skull tumors 23(3.6%). 3) Average incidence rate of tumors was 3.5/year/100,000 population, 3.1 for Chonnam province, 4.4 for Chonbuk province. 4) Among the brain tumors, glial tumors were the most common(28.4%), and followed by meningiomas(18%), pituitary tumors(15.2%), metastatic tumors(8.9%), Among the intraspinal tumors, neurinomas and neurofibromas were found most frequently(41.5%), and rests were metastatic tumors(23.4%), meningiomas(9.5%) in order. 5) Sexual predilection of tumors was as follows : male preponderance was noted for oligodendrogliomas(9:1), metastatic tumors(2.3:1), glioblastomas multiforme(GM)(1.8:1) cysticercosis(1.6:1), and female preponderance for meningiomas(1:3.2), pituitary tumors(1:2), paragonimiases(1:1.5). 6) The incidence rate of brain tumors in children below 15 years was 11.8% and that which occured infratentorially was 47.5%. 7) The brain tumors were found mainly in cerebral hemispheres, in which area most of tumors were meningiomas, astrocytomas in order. In sellar, parasellar most of tumors were meningiomas astrocytomas in order. In sellar, parasellar and suprasellar region, the majority of tumors were pituitary tumors and meningiomas. 8) Cysticercosis showed a predilection for the sixth and seventh decades, meningiomas, metastatic tumors, neurinomas for sixth decade, GM and supratentorial astrocytomas for fourth, fifth and sixth decades, oligodendroliomas for fifth decade, infratentorial astrocytomas, medulloblastomas and craniopharyngiomas for first and second decades. 9) In the spinal tumors, the favorable site was thoracic region and majority of them were located intradural extramedullarily and extradurally in similar incidence.

Analysis of Upper Cervical Injuries

During the past five years we have treated twenty-seven cases of upper cervical injury among total three hundred and seventeen spine injuries. A follow-up study has done on twenty-one upper cervical injuries and the result is reported. The incidence of upper cervical injury was 8.5% of the total spine injury and 17.5% of the cervical injury. Almost all of the injuries(95.2%) were caused by traffic accidents and falls. The types of injury were odontoid fracture(38.1%), hangman's fracture(28.6%), atlanto-axial instability(19.1%), tear drop fracture of the axis(9.5%), and Jefferson's fracture(4.8%). Chief complaints on admission were motor weakness(57.1%), neck pain with limitted range of motion(42.9%), and sensory disturbance was noted in six cases of the motor weakness group(28.6%). Out of twenty-one cases, operative fixation was performed in eight cases with good result in five(62.5%) and thirteen patients were treated conservatively with eleven cases(84.6%) of good result. In chronic nonunited or malnunited cases, it seems to be safer to fuse the level both by anterior and posterior routes than by either route alone because it is not always stable and needs long period of immobilization.