Machine Learning-Based Prediction of Functional Disability: a Cohort Study of Japanese Older Adults in 2013-2019.

BACKGROUND: It is important to identify older adults at high risk of functional disability and to take preventive measures for them at an early stage. To our knowledge, there are no studies that predict functional disability among community-dwelling older adults using machine learning algorithms. OBJECTIVE: To construct a model that can predict functional disability over 5 years using basic machine learning algorithms. DESIGN: A cohort study with a mean follow-up of 5.4 years. PARTICIPANTS: We used data from the Japan Gerontological Evaluation Study, which involved 73,262 people aged ≥ 65 years who were not certified as requiring long-term care. The baseline survey was conducted in 2013 in 19 municipalities. MAIN MEASURES: We defined the onset of functional disability as the new certification of needing long-term care that was ascertained by linking participants to public registries of long-term care insurance. All 183 candidate predictors were measured by self-report questionnaires. KEY RESULTS: During the study period, 16,361 (22.3%) participants experienced the onset of functional disability. Among machine learning-based models, ridge regression (C statistic = 0.818) and gradient boosting (0.817) effectively predicted functional disability. In both models, we identified age, self-rated health, variables related to falls and posture stabilization, and diagnoses of Parkinson's disease and dementia as important features. Additionally, the ridge regression model identified the household characteristics such as the number of members, income, and receiving public assistance as important predictors, while the gradient boosting model selected moderate physical activity and driving. Based on the ridge regression model, we developed a simplified risk score for functional disability, and it also indicated good performance at the cut-off of 6/7 points. CONCLUSIONS: Machine learning-based models showed effective performance prediction over 5 years. Our findings suggest that measuring and adding the variables identified as important features can improve the prediction of functional disability.

Mixed HCV Infection of Genotype 1B and Other Genotypes Influences Non-response during Daclatasvir + Asunaprevir Combination Therapy.

Daclatasvir (DCV) + asunaprevir (ASV) combination therapy has become available for patients with hepatitis C virus (HCV) serogroup 1 infection. We studied the efficacy of this therapy by focusing on the factors associated with sustained virological responses (SVR) including resistance-associated variants (RAVs) and mixed infection of different HCV genotypes. We enrolled 951 HCV serogroup 1-positive patients who received this combination therapy at our hospital or affiliated hospitals. The presence of RAVs in non-structural (NS) regions 3 and 5A was analyzed by direct sequencing. HCV genotypes were determined by PCR with genotype-specific primers targeting HCV core and NS5B regions. SVR was achieved in 91.1% of patients. Female sex, age > 70 years, and RAVs were significantly associated with non-SVR (p<0.01 for all). Propensity score-matching results among the patients without RAVs regarding sex, age, and fibrosis revealed that mixed HCV infection determined by HCV NS5B genotyping showed significantly lower SVR rates than 1B-mono infection (p=0.02). Female sex and RAVs were significant factors associated with treatment failure of this combination therapy for patients with HCV serogroup 1 infection. Mixed HCV infection other than 1B-mono infection would be useful for predicting treatment failure.

Risk of secondary osteoporosis due to lobular cholestasis in non-cirrhotic primary biliary cholangitis.

BACKGROUND AND AIM: It remains unclear whether primary biliary cholangitis (PBC) represents a risk factor for secondary osteoporosis. METHODS: A case-control study was conducted to examine bone mineral density and bone turnover markers in middle-aged postmenopausal PBC patients without liver cirrhosis. We compared the incidence of low bone mineral density between propensity-score matched subgroups of PBC patients and healthy controls and investigated the mechanisms underlying unbalanced bone turnover in terms of the associations between bone turnover markers and PBC-specific histological findings. RESULT: Our analysis included 128 consecutive PBC patients, all postmenopausal women aged in their 50s or 60s, without liver cirrhosis or fragility fracture at the time of PBC diagnosis. The prevalence of osteoporosis was significantly higher in the PBC group than in the control group (26% vs 10%, P = 0.015, the Fisher exact probability test). In most PBC patients (95%), the level of bone-specific alkaline phosphatase was above the normal range, indicating increased bone formation. On the other hand, the urine type I collagen-cross-linked N-telopeptide showed variable levels among our PBC patients, indicating unbalanced bone resorption. Advanced fibrosis was associated with low bone turnover. Lobular cholestasis, evaluated as aberrant keratin 7 expression in hepatocytes, showed significant negative correlations with bone formation and resorption, indicating low bone turnover. CONCLUSION: Our results show that, compared with healthy controls, even non-cirrhotic PBC patients have significantly higher risk of osteoporosis. Moreover, lobular cholestasis was associated with low bone turnover, suggesting this feature of PBC may itself cause secondary osteoporosis in PBC patients.

Entecavir Reduces Hepatocarcinogenesis in Chronic Hepatitis B Patients.

Chronic hepatitis B (CHB) leads to cirrhosis and hepatocellular carcinoma (HCC). With a cohort of 1,206 CHB patients who visited Okayama University Hospital and related hospitals in 2011 and 2012, we compared the incidence rates of HCC among the patients grouped by age, hepatitis B virus (HBV) DNA, hepatitis B e antigen (HBeAg), and treatment. HCCs were observed in 115 patients with the median observation period of 1,687 days. Among the HCC patients aged > 35 years, HBV DNA > 4 log copies/mL and positive HBeAg at diagnosis (n＝184), the HCC incidence rate was 8.4% at 5 years in the entecavir (ETV)-treated patients, 21.8% in the lamivudine (LVD)-treated patients, and 26.4% among the patients not treated with drugs. The cumulative HCC incidence was significantly reduced in the ETV-treated patients compared to those treated with LVD or not treated (p＝0.013). Among the patients aged >35 years with HBV DNA > 4 log copies/mL and negative HBeAg (n＝237), the cumulative HCC incidence was 14.6% in 5 years in ETV group and 13.9% among those not treated with a drug (p＞0.05). Only small numbers of HCCs occurred in other patients. In CHB patients aged > 35 years with HBV DNA > 4 log copies/mL and positive HBeAg, ETV treatment is recommended for the suppression of HCC development.

Effect of previous interferon treatment on outcome after curative treatment for hepatitis C virus-related hepatocellular carcinoma.

BACKGROUND AND AIMS: Treatment of chronic hepatitis C virus (HCV) infection with interferon (IFN) prevents the development of hepatocellular carcinoma (HCC). The purpose of this study was to clarify the effect of previous IFN treatment before the development of HCC on recurrence and survival in HCV-related HCC patients. METHODS: Three hundred ninety-five patients who underwent curative treatment for HCV-related HCC were enrolled. Of these, 124 had received IFN treatment before the development of HCC (17 achieved sustained virological response [SVR group] and 107 did not [non-SVR group]), whereas 271 patients had never received IFN treatment (IFN-untreated group). The first and second recurrence and survival rates in these patient groups were statistically analyzed. RESULTS: The first HCC recurrence rate was similar among patient groups. In contrast, the second HCC recurrence rate was significantly lower in the SVR group than in the non-SVR group (p = 0.003) and the IFN-untreated group (p = 0.006). In multivariate analysis, platelet count (p = 0.033) and number of tumors (p = 0.001) were associated with the first HCC recurrence, while SVR (p = 0.002) was the only factor associated with the second HCC recurrence. The survival rate was higher in the SVR group than in non-SVR and IFN-untreated groups, and SVR to previous IFN treatment was an independent factor associated with better survival (p < 0.001). CONCLUSIONS: SVR to previous IFN treatment before the development of HCV-related HCC was associated with lower risk of the second recurrence of HCC and better survival.

Peppermint oil solution is useful as an antispasmodic drug for esophagogastroduodenoscopy, especially for elderly patients.

BACKGROUND: Although hyoscine butyl bromide (HB) and glucagon (GL) are often used as antispasmodic drugs during esophagogastroduodenoscopy (EGD), these agents may cause adverse effects. Recently, it was reported that peppermint oil solution (PO) was very effective and had few side effects. AIM: We clarified the efficacy and usefulness of PO as an antispasmodic during upper endoscopy, especially for elderly patients. METHODS: This study was a non-randomized prospective study. The antispasmodic score (1-5, where 5 represents no spasm) was defined according to the degree of spasms of the antrum and difficulty of biopsy. We compared the antispasmodic scores between non-elderly patients (younger than 70) and elderly patients (70 years old or older) according to the antispasmodic agent. RESULTS: A total of 8,269 (Group PO: HB: GL: NO (no antispasmodic) = 1,893: 6,063: 157: 156) EGD procedures were performed. There was no significant difference in the antispasmodic score between Group PO (mean score ± standard deviation: 4.025 ± 0.925) and Group HB (4.063 ± 0.887). Among the non-elderly patients, those in Group PO (n = 599, 3.923 ± 0.935) had a worse antispasmodic score than those in Group HB (n = 4,583, 4.062 ± 0.876, P < 0.001). However, among the elderly patients, those in Group PO (n = 1,294, 4.073 ± 0.917) had similar scores to those in Group HB (n = 1,480, 4.064 ± 0.921, P = 0.83), and significantly better scores than those in Group GL (n = 69, 3.797 ± 0.933, P < 0.05). CONCLUSION: Peppermint oil was useful as an antispasmodic during EGD, especially for elderly patients.

Estimation of children's thyroid equivalent doses in 16 municipalities after the Fukushima Daiichi Nuclear Power Station accident.

To elucidate the association between radiation dose and thyroid cancer after the 2011 Fukushima Daiichi Nuclear Power Station (FDNPS) accident, it is essential to estimate individual thyroid equivalent doses (TEDs) to children. In a previous study, we reported a methodology for reconstructing TEDs from inhalation. That methodology was based on individual behavioral survey sheets of the Fukushima Health Management Survey (FHMS) combined with a spatiotemporal radionuclides database constructed by an atmospheric transport, diffusion, and deposition model (ATDM)-the Worldwide version of System for Prediction of Environmental Emergency Dose Information (WSPEEDI) in seven municipalities. In the present study, we further refined our methodology and estimated the combined TEDs from inhalation and ingestion among children in 16 municipalities around the nuclear power station utilizing 3256 individual whereabouts questionnaire survey sheets. Distributions of estimated TEDs were similar to estimates based on direct thyroid measurements in 1080 children in Iwaki City, Kawamata Town, Iitate Village, and Minamisoma City. Mean TEDs in 1-year-old children ranged from 1.3 mSv in Date City to 14.9 mSv in Odaka Ward in Minamisoma City, and the 95th percentiles varied from 2.3 mSv in Date City to 28.8 mSv in Namie Town. In the future, this methodology can be useful for the epidemiological studies of thyroid cancer after the FDNPS accident.

Effect of pegylated interferon therapy on intrahepatic recurrence after curative treatment of hepatitis C virus-related hepatocellular carcinoma.

BACKGROUND: We wished to determine whether pegylated interferon (PEG-IFN) therapy after curative treatment of hepatocellular carcinoma (HCC) prevents a recurrence of HCC. METHODS: Thirty-seven HCC patients with hepatitis C virus (HCV) infection who were treated with PEG-IFN after curative treatment (PEG-IFN group) and 145 controls without IFN therapy (non-IFN group) were enrolled. The overall survival and recurrence-free survival rates were compared between the groups, and the predisposing factors for recurrence and survival were analyzed. The rates were also examined by propensity score (PS) matched analysis that could minimize selection biases. RESULTS: The median follow-up period was 3.7 years. The 5-year survival rate in the PEG-IFN group (91%) was significantly higher than that in the non-IFN group (56%; P < 0.01). The rate of the second recurrence but not that of the first recurrence of HCC in the sustained virological responder (SVR) group was lower than that in the non-IFN group (P = 0.03). Improvement of survival by PEG-IFN and low rate of second recurrence in the SVR group were also observed in PS matched analysis. Multivariate analysis revealed that PEG-IFN therapy and high serum albumin were good prognostic factors for survival. Although low serum albumin and large and multiple tumors were risk factors for the first recurrence, non-SVR and low serum albumin were risk factors for the second recurrence. CONCLUSION: PEG-IFN-therapy after curative treatment of HCC improved the rate of survival, and SVR was found to be closely correlated with the prevention of recurrence.

Prognostic model for hepatocellular carcinoma with time-dependent factors.

The purpose of this study was to build a prognostic model of hepatocellular carcinoma (HCC) using time-dependent covariates to re-evaluate the prognosis at any stage of the disease. The subjects were consecutive HCC patients who were treated at our institute between 1995 and 2007. We constructed time-fixed and time-dependent prognostic models with a training group (n=336) and compared the prognostic abilities between conventional Cancer of the Liver Italian Program (CLIP) scores, Japan Integrated Staging (JIS) scores, an Okuda classification, and our prognostic models in the testing group (n=227) with the c-index. The time-dependent prognostic model consisted of main tumor size, tumor number, portal vein invasion, distant metastasis, alpha-fetoprotein, des-gamma-carboxy prothrombin (DCP), bilirubin, and albumin and the weighted scores were set for each factor depending on the hazard ratio for the prognosis. The prognostic index was determined by summing the scores. The c-index values for the CLIP scores, JIS scores, Okuda classification, and our time-dependent model were 0.741, 0.727, 0.609, and 0.870, respectively. These results indicate that our time-dependent model can estimate the prognosis of HCC more precisely than traditional time-fixed models and can be used to re-predict the prognosis of HCC.

Large waist circumference is a risk factor for reflux esophagitis in Japanese males.

BACKGROUND/AIMS: The prevalence of reflux esophagitis, which might lead to development of Barrett's esophagus and esophageal adenocarcinoma, has been increasing. The aim of this study was to assess risk factors for reflux esophagitis. METHODS: We conducted a cross-sectional study of 1,495 Japanese subjects undergoing health checkups (822 males and 673 females; median age 50 years) at a tertiary care center. RESULTS: One hundred and twenty-seven subjects (8%) had reflux esophagitis and hiatal hernia was observed in 292 subjects (20%). Reflux esophagitis (13 vs. 3%) and hiatal hernia (28 vs. 9%) were more frequent in males than females. Significant differences in clinical backgrounds were observed between females and males. Multivariate logistic regression analyses revealed that hiatal hernia (OR 6.63, 95% CI 2.47-17.8; p = 0.0002) was associated with reflux esophagitis in females. In males, age (per 1-year increment: OR 0.96, 95% CI 0.94-0.99; p = 0.007), hiatal hernia (OR 3.16, 95% CI 2.05-4.87; p < 0.0001) and waist circumference (per 1-cm increase: OR 1.09, 95% CI 1.02-1.15; p = 0.006) were associated with reflux esophagitis. CONCLUSIONS: Abdominal obesity may be an important risk factor for reflux esophagitis in males compared with females.

Estimation of internal dose from tap water after the Fukushima Daiichi Nuclear Power Station accident using newly obtained data.

Massive release of radioactive materials into the atmosphere occurred due to the Fukushima Daiichi Nuclear Power Station (FDNPS) accident in March 2011. The World Health Organization (WHO) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reported the results of dose estimation to assess the health effect of the accident and both reports state that their assessments of internal and external exposure doses contain certain uncertainties due to uncertainties inherent to the basic data. Therefore, estimation of the internal dose from tap water was conducted in this study by utilizing a database of deposition calculated by an atmospheric transfer, dispersion and deposition model (ATDM) in conjunction with the newly obtained data on the volume of daily water intake obtained by a web-based survey. The median mean and 95-percentile of thyroid equivalent doses were estimated for 1-year and 10-year children and adults in 12 municipalities in the evacuation area in Fukushima prefecture. The present mean thyroid dose estimations for 1-year children (0.4-16.2 mSv) are smaller than the corresponding values in the UNSCEAR 2013 report (1.9-49 mGy). Dose-modifying factors in the Japanese or local community are discussed.

ESTIMATION OF EFFECTIVE DOSE FROM EXTERNAL EXPOSURE DUE TO SHORT-LIVED NUCLIDES IN THE PREFECTURES SURROUNDING FUKUSHIMA.

The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident resulted in a release of radionuclides into the environment. Since the accident, measurements of radiation in the environment such as air dose rate and deposition density of radionuclides have been performed by various organizations and universities. In particular, Japan Atomic Energy Agency (JAEA) has been performing observations of air dose rate using a car-borne survey system continuously over widespread areas. Based on the data measured by JAEA, we estimated effective dose from external exposure in the prefectures surrounding Fukushima. Since car-borne survey started a few months after the accident, the main contribution to measured data comes from 137Cs and 134Cs whose half-lives are relatively long. Using air dose rate of 137Cs and 134Cs and the ratio of deposition density of short-lived nuclides to that of 137Cs and 134Cs, we also estimated contributions to the effective dose from other short-lived nuclides.

Nomograms to Predict the Disease-free Survival and Overall Survival after Radiofrequency Ablation for Hepatocellular Carcinoma.

Objective The purpose of this study was to construct nomograms for the disease-free survival (DFS) and overall survival (OS) of post-radiofrequency ablation (RFA) patients with hepatocellular carcinoma (HCC). Furthermore, we compared the prognostic predictive ability of these nomograms for estimating per-patient outcomes with that of traditional staging systems. Methods We retrospectively enrolled 298 patients in the training set and 272 patients in the validation set who underwent RFA for HCC. The nomograms for the DFS and OS were constructed from the training set using the multivariate Cox proportional hazards model. The discriminatory accuracy of the models was compared with traditional staging systems by analyzing the Harrell's C-index. Results The DFS nomogram was developed based on the tumor size, tumor number, aspartate aminotransferase (AST), albumin, age, and α-fetoprotein. The OS nomogram was developed based on the tumor size, the model for end-stage liver disease, AST, and albumin. Our DFS and OS nomograms had good calibration and discriminatory abilities in the training set, with C-indexes of 0.640 and 0.692, respectively, that were greater than those of traditional staging systems. The C-indexes of our DFS and OS nomograms were also greater than those of traditional staging systems in the validation set, with C-indexes of 0.614 and 0.657, respectively. RFA patients were stratified into low- and high-risk groups based on the median nomogram scores. High-risk patients receiving surgical resection (SR) were associated with a better DFS and OS than those undergoing RFA. However, the DFS and OS were similar between the low-risk RFA and SR groups. Conclusion We constructed reliable and useful nomograms that accurately predict the DFS and OS after RFA for early-stage HCC patients. These graphical tools are easy to use and will assist physicians during the therapeutic decision-making process.

Surgical Resection for Hepatocellular Carcinoma with Cardiac Cirrhosis after the Fontan Procedure.

A 29-year-old woman who underwent the Fontan procedure at 10 years of age had an incidental finding of liver masses on abdominal ultrasonography. Subsequent gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid magnetic resonance imaging showed a 15 mm hypervascular mass with washout in the hepatobiliary phase in liver segment 4 (S4), and an 18 mm hypervascular mass without washout in the hepatobiliary phase in liver segment 2 (S2). The S2 liver mass was pathologically diagnosed to be a regenerative nodule by an ultrasound-guided needle biopsy, and the S4 liver mass was pathologically diagnosed as a poorly differentiated hepatocellular carcinoma after partial hepatectomy.

Long-term combined therapy with very-low-dose peginterferon and ursodeoxycholic acid decreased the spleen size in a patient with hepatitis C virus-related cirrhosis.

A 42-year-old woman with hepatitis C virus-related cirrhosis underwent peginterferon alpha-2b therapy combined with ribavirin but could not achieve a sustained viral response. Following discontinuation of this combined therapy, the patient's serum transaminase levels suddenly became elevated. Therefore, the administration of very-low-dose peginterferon alpha-2a with ursodeoxycholic acid was introduced. Thereafter, the patient's serum transaminase levels gradually improved. Four years later, enhanced computed tomography showed shrinkage of the spleen and enlargement of the liver. Long-term combined therapy with very-low-dose peginterferon and ursodeoxycholic acid may be effective not only in preventing disease progression, but also in improving portal hypertension in patients hepatitis C virus-related cirrhosis.

Partial splenic embolization facilitates the adherence to peginterferon in chronic hepatitis C with thrombocytopenia.

OBJECTIVE: Platelet counts before starting the treatment affect the discontinuation and dose reduction of peginterferon in chronic hepatitis C. Thrombocytopenia leads to failure to achieve sustained virological response. This study was undertaken to evaluate the efficacy of partial splenic embolization (PSE) prior to starting peginterferon therapy combined with ribavirin in chronic hepatitis C patients showing thrombocytopenia. PATIENTS AND METHODS: We compared the clinical features of 11 patients receiving PSE (PSE group) prior to starting the combined therapy with those of 13 patients not receiving PSE (non-PSE group). All of the patients showed platelet counts ≤12×10(4)/mm(3) and serum hepatitis C virus-RNA levels ≥100 KIU/mL at baseline. The end-point of PSE was a volume of splenic infarction over 75%. Peginterferon alpha-2b at a dose of 1.2 µg/kg was administered by subcutaneous injection once a week. The dose of ribavirin was weight adjusted. RESULTS: PSE was successfully performed without serious adverse events. The period from PSE to starting the combined therapy was 14 (6-27) days. After PSE, platelet counts were significantly increased. In PSE group, platelet counts during the combined therapy were maintained above those at baseline. In non-PSE group, platelet counts at the 2nd week after the start of the combined therapy significantly decreased to less than those at baseline. Overall, 80% adherence to expected peginterferon dose was not achieved in 5 patients (45%) of PSE group and in 11 (85%) of non-PSE group (p=0.043). CONCLUSION: Increased platelet counts after PSE facilitates the adherence to peginterferon therapy in chronic hepatitis C patients with thrombocytopenia.

Prevention of biliary complication in radiofrequency ablation for hepatocellular carcinoma-Cooling effect by endoscopic nasobiliary drainage tube.

BACKGROUND AND STUDY AIMS: Biliary stricture after radiofrequency ablation (RFA) for nodules of hepatocellular carcinoma (HCC) close to major bile ducts sometimes causes septic complications and liver failure. Therefore, it may require interventional drainage for decompression during the follow-up period. The purpose of this study is to clarify the feasibility and safety of bile duct cooling using an endoscopic nasobiliary drainage (ENBD) tube in RFA for HCC close to major bile ducts. PATIENTS AND METHODS: Between August 2003 and July 2007, 14 consecutive patients (14 nodules) undergoing RFA with cooling by an ENBD tube for HCCs close to major bile ducts were enrolled in this study. We infused chilled saline solution via the ENBD tube at 1ml/s to prevent heat damage during RFA. As controls, 11 patients (13 nodules) undergoing RFA without cooling close to major bile ducts between April 2001 and August 2003 were reviewed. The major outcomes for evaluation were biliary complications and the secondary outcome was local tumor recurrence. RESULTS: There were no significant differences in tumor recurrence between the two groups. However, the rate of biliary complications was significantly lower in the cooling group than in the non-cooling group (0% vs. 39%, P=0.02). CONCLUSIONS: Cooling of bile ducts via an ENBD tube can prevent biliary complications induced by RFA of HCC close to major bile ducts without increasing local recurrence. This technique increases indication of RFA in difficult cases.

A combination treatment of entecavir and early-phase corticosteroid in severe exacerbation of chronic hepatitis B.

Of patients with severe exacerbation of chronic hepatitis B accompanied by jaundice and coagulopathy, 20%-30% have a fatal outcome. In this report, we describe 2 cases of severe exacerbation of chronic hepatitis B with jaundice and coagulopathy who were successfully treated with a combination of entecavir and corticosteroid. In both cases, rapid reductions in serum hepatitis B virus (HBV)-DNA levels were observed, and corticosteroid was stopped after serum HBV-DNA levels became undetectable. Entecavir treatment was continued. Generally, entecavir treatment reduced serum HBV-DNA levels rapidly, although the improvement in liver function was delayed by a few weeks. During this time lag, liver cell injury continued and the disease progressed. Corticosteroid suppressed the excessive host immune response and was useful for stopping progressive deterioration. A combination of entecavir and early-phase corticosteroid may be a useful treatment in severe exacerbation of chronic hepatitis B.