Preoperative nutritional evaluation, surgical site infection, and prognosis in patients with oral cancer.

OBJECTIVES: The risk of postoperative infection after reconstructive oral cancer surgery is high and poses a problem in perioperative management. The objective of this study was to verify the association between preoperative nutritional indicators, surgical site infection (SSI), and long-term prognosis after reconstruction for oral cancer. STUDY DESIGN: Sixty-seven patients admitted to a dental hospital were enrolled. The following nutritional indicators were examined: serum albumin level, modified Glasgow Prognostic Score, Miki's Glasgow Prognostic Score, prognostic nutritional index, platelet/lymphocyte ratio, neutrophil/lymphocyte ratio, lymphocyte/monocyte ratio, and the Controlling Nutritional Status tool. Statistical analyses were conducted to determine potential risk factors for SSI. RESULTS: The Cox proportional hazards model demonstrated that SSI and platelet/lymphocyte ratio ≥211.4 were independent prognostic factors affecting survival. The results demonstrated that albumin <4.0 and platelet/lymphocyte ratio ≥211.4 were risk factors for SSI. Furthermore, albumin <4.0, platelet/lymphocyte ratio ≥211.4, and SSI were correlated with prognosis. Preoperative nutritional indicators were associated with SSI and prognosis in patients with oral cancer after reconstructive surgery. CONCLUSION: Preoperative nutritional therapy is crucial for improving therapeutic outcomes in patients with oral cancer who require reconstructive surgery.

Age-Related Changes in Item Responses to the Patient Health Questionnaire-9: Evidence From the National Health and Nutrition Examination Survey.

BACKGROUND: Epidemiological studies have shown that total scores in depression screening scales change with age, but the mechanism underlying these age-related changes remains unclear. Previous research has indicated that item responses in depression screening scales exhibit characteristic distributions in the general population. We analyzed Patient Health Questionnaire-9 (PHQ-9) data from a representative survey conducted in the USA, to determine how the response pattern for each item changed with age and whether the pattern of responses contributed to age-related changes in total scores. METHODS: We analyzed PHQ-9 data for 17,274 participants in the 2011-2016 National Health and Nutrition Examination Survey. The PHQ-9 allows respondents to self-rate the frequency of depressive symptoms using a four-point scale ranging from "not at all" to "nearly every day". RESULTS: The lines for all nine item responses followed the same characteristic pattern across all age groups, which was marked by intersection at a single point between "not at all" and "several days" and parallel patterns between "several days" and "nearly every day" on a logarithmic scale. The probability of "nearly every day" showed a reverse U-shaped pattern, in that it was low from 12-29 years, increased during 30-50 years, and then decreased at ≥60 years. The age-related change in the probability of a response of "nearly every day" coincided with the trajectory of the PHQ-9 total scores. CONCLUSIONS: This study demonstrated that item responses for the PHQ-9 followed a similar mathematical pattern across the adult lifespan. Moreover, our findings suggested that the probability of a response of "nearly every day" played an important role in age-related changes in PHQ-9 total scores across adulthood.

Responses to depressive symptom items exhibit a common mathematical pattern across the European populations.

The theoretical distribution of responses to depressive symptom items in a general population remains unknown. Recent studies have shown that responses to depressive symptom items follow the same pattern in the US and Japanese populations, but the degree to which these findings can be generalized to other countries is unknown. The purpose of this study was to conduct a pattern analysis on the EU population's responses to depressive symptom items using data from the Eurobarometer. The Eurobarometer questionnaires include six depressive symptom items from the 12-item General Health Questionnaire. The pattern analysis revealed that, across the entire EU population, the ratios between "score = 2" and "score = 1" and between "score = 3" to "score = 2" were similar among the six items and resulted in a common pattern. This common pattern was characterized by an intersection at a single point between "score = 0" and "score = 1" and a parallel pattern between "score = 1" and "score = 3" on a logarithmic scale. Country-by-country analyses revealed that the item responses followed a common characteristic pattern across all 15 countries. Our results suggest that responses to depressive symptom items in a general population follow the same characteristic pattern regardless of the specific country.

Distribution of psychological distress is stable in recent decades and follows an exponential pattern in the US population.

The prevalence of psychological distress is fairly stable in industrialised countries in recent decades, but the reasons for this stability remain unknown. To investigate the mechanisms underlying stability of psychological distress in the general population of the United States, we analysed the mathematical patterns of the distribution of psychological distress in recent decades. The present study utilised the Kessler psychological distress scale (K6) data from the 1997‒2017 United States National Health Interview Survey. We used overlap coefficients and graphical analysis to investigate the stability and mathematical patterns of the K6 distribution. Overlap coefficients and graphical analysis demonstrated that the distribution of K6 total scores was stable in the United States over the past two decades. Furthermore, the distributions of K6 total scores exhibited an exponential pattern, with the exception of the lower end of the distribution. These findings suggest that the lack of change in the prevalence of psychological distress over several decades is due to the stability of psychological distress distribution itself. Furthermore, the stability of the distribution of psychological distress over time may be linked to the exponential pattern of psychological distress distribution.

Further evidence that item responses on the Kessler Psychological Distress Scale exhibit the characteristic pattern in the general population.

BACKGROUND: Previous studies suggested that item responses on the 6-item Kessler Psychological Distress Scale (K6) exhibit characteristic distributions among the general population. To confirm the reproducibility of these findings, we conducted a pattern analysis of the K6 item responses using large-scale data from a US representative survey. METHODS: Data were drawn from the 2016, and 2017 National Health Interview Survey in the United States (33,028, and 26,742 individuals, respectively). We analyzed the patterns of item responses for the six items using normal and logarithmic scales and proposed a model of item responses. RESULTS: The lines for item responses showed the same pattern among the six items, characterized by crossing at a single point between "none" and "a little," and parallel patterns from "a little" to "all of the time" on a logarithmic scale. The ratio of "some" to "a little," "most" to "some," and "most" to "all of the time" were similar across the six items. The model of item responses, which was based on the findings that the decreasing ratios of "some" to "a little," "most" to "some," and "all of the time" to "most" were similar across the six items, explained the characteristic patterns of item responses. CONCLUSION: These results provide further evidence that item responses on the K6 follow a particular distribution pattern among the general population.

Stability of the Distribution of Patient Health Questionnaire-9 Scores Against Age in the General Population: Data From the National Health and Nutrition Examination Survey.

Background: Epidemiological studies using the nine-item Patient Health Questionnaire (PHQ-9) have reported inconsistencies regarding the relationship between age and total scores. To determine whether this discrepancy is due to the stability of the distribution of PHQ-9 total scores against age, we investigated whether the total score distribution remains stable during adulthood, and also investigated the mathematical patterns of the total score distribution. Methods: The present study utilized data from 15,847 participants of the 2009-2014 United States National Health and Nutrition Examination Survey, all of whom responded to all PHQ-9 items. The stability of the total score distribution among different age groups was examined using overlap coefficients and graphical analysis. Results: High overlap coefficients were observed between all age groups for the distributions of PHQ-9 total scores, suggesting that the distribution of PHQ-9 total scores remains stable against age. Graphical analysis demonstrated that distributions of PHQ-9 total scores were similar across age groups. In addition, distributions of PHQ-9 total scores exhibited an exponential pattern, except at the lower end of the distribution. Conclusions: Our findings indicate that the stability of the distribution of PHQ-9 total scores throughout adulthood may underlie inconsistencies in the evidence regarding age-related changes in total depression scores.

Distribution of item responses and total item scores for the Center for Epidemiologic Studies Depression Scale (CES-D): Data from the Irish Longitudinal Study on Ageing (TILDA).

BACKGROUND: Previous studies have shown that item responses and total scores on depression screening scales follow characteristic distribution patterns in the United States and Japanese general populations. However, the degree to which these findings, especially in terms of item responses, can be generalized to a European population is unknown. Thus, we analyzed the item responses and total score distribution for the Center for Epidemiologic Studies Depression Scale (CES-D) in a representative Irish cohort from a large, recent study-the Irish Longitudinal Study on Ageing (TILDA). METHODS: We used CES-D data from the 2009-2011 TILDA (8504 individuals). Responses for the 16 depressive symptoms included "rarely," "some of the time," "occasionally," and "all of the time." Item response patterns and total score distribution across these 16 depressive symptom items were examined using graphical analyses and exponential regression modeling. RESULTS: Lines for item responses followed the same pattern across the 16 items. These lines were characterized by intersections in the vicinity of a single point between "rarely" and "some of the time" and parallel patterns from "some of the time" to "all of the time" on a log-normal scale. Total scores for the 16 items exhibited an exponential pattern, except for at the lower end of the distribution. CONCLUSIONS: The present findings suggest that item responses and total scores on depression screening scales among the general population follow the same characteristic patterns across populations from multiple nations.

Distributional patterns of item responses and total scores on the PHQ-9 in the general population: data from the National Health and Nutrition Examination Survey.

BACKGROUND: Recently, item responses and total scores on depression screening scales have been reported to have characteristic distributions in the general population. The distributional pattern of responses to the Patient Health Questionnaire-9 (PHQ-9) in the general population has not been well studied. Thus, we carried out a pattern analysis of the PHQ-9 item responses and total scores in US adults. METHODS: Data (5372 individuals) were drawn from the 2013-2014 National Health and Nutrition Examination Survey in the United States. The item responses and total score distributions of the PHQ-9 data were investigated with graphical analysis and exponential regression model. RESULTS: Lines of item responses showed the same pattern among the nine items, characterized by crossing at a single point between "not at all" and "several days" and a parallel pattern from "several days" to "nearly every day" on a log-normal scale. The total score distribution of the PHQ-9 exhibited an exponential pattern, except for at the lower end of the distribution. CONCLUSIONS: The present results support that the item responses and total scores on the PHQ-9 in the general population show the same characteristic patterns, consistent with the previous studies using the Center for Epidemiologic Studies Depression Scale (CES-D) and Kessler Screening Scale for Psychological Distress (K6).

Item Response Patterns on the Patient Health Questionnaire-8 in a Nationally Representative Sample of US Adults.

Recent studies have shown that item responses on the Center for Epidemiologic Studies Depression Scale (CES-D) and Kessler Screening Scale for Psychological Distress (K6) exhibit the same characteristic item response patterns among the general population. However, the distributional patterns of responses on the Patient Health Questionnaire-8 (PHQ-8) among the general population have not been adequately studied. Thus, we conducted a pattern analysis of PHQ-8 item responses among US adults. Data (18,446 individuals) were obtained from the 2015 Behavioral Risk Factor Surveillance Survey (BRFSS). Item responses on the BRFSS version of the PHQ-8 were scored using the number of days response set and then converted to the original 4-point scale. The patterns of item responses were analyzed through graphical analysis. Lines of item responses scored using the number of days response set showed the same pattern among the eight items, characterized by crossing at a single point between "0 days" and "1 day," and parallel fluctuation from "1 day" to "14 days" on a semi-logarithmic scale. Lines of item responses converted to the 4-point scale also showed the same characteristic pattern among the eight items. The present results demonstrate that the item responses on the PHQ-8 show the same characteristic patterns among items, consistent with the CES-D and the K6.

Exponential distribution of total depressive symptom scores in relation to exponential latent trait and item threshold distributions: a simulation study.

OBJECTIVES: Total depressive symptom scores in the general population have been reported to follow an exponential distribution except at the lowest end of the range of scores. To verify the hypothesis that total depressive symptom scores follow the distribution of the latent trait, we performed a simulation study of depressive symptom scoring modeled after the Revised Clinical Interview Schedule (CIS-R). To simulate the scoring of ordinal scale items in CIS-R, two sets of random numbers were generated, one expressing the degree of the latent trait of depressive symptoms and another expressing the threshold for each item. Random latent trait numbers greater than those of item thresholds indicated the presence of specific symptoms. RESULTS: When exponential distribution was set to the latent trait's random numbers and each item's threshold had a certain degree of standard deviation, simulated total depressive symptom scores showed a linear pattern except at the lowest end of scores with a log-normal scale. Our results suggest that total depressive symptom scores follow the distribution of the latent trait of depressive symptoms due to the property of ordinal scales, which is characterized by individual differences in the threshold of each item.

Characteristic distribution of the total and individual item scores on the Kessler Screening Scale for Psychological Distress (K6) in US adults.

BACKGROUND: The distributional pattern of total scores on depression screening scales in the general population has not been well studied. Recent studies suggest that the total scores on depression screening scales follow an exponential pattern, with the exception of the lower end of the distribution. To further investigate the findings, we determined the distributions of the total and individual item scores on the Kessler Screening Scale for Psychological Distress (K6). METHODS: Data were obtained from the National Survey of Midlife Development in the United States. Participants comprised 6,223 individuals between the ages of 25 and 74. The distributions of the total and individual item scores in various combinations were investigated with histograms and regression analysis. RESULTS: Irrespective of the combination of items, the total and individual item scores followed an exponential pattern except at the lower scores. The estimated rate parameters of regression analysis were similar among distributions with the same number of chosen items. At the lower scores, the distributional patterns of total scores varied according to the ratio of "a little" to "none" for each item response. CONCLUSIONS: The present results have the potential to estimate the distribution of depressive symptoms in the general population. While the degree of depressive symptoms varies from individual to individual, an entire population may show a certain mathematical distribution.

Safety Profile of Telaprevir-Based Triple Therapy in Elderly Patients: A Real-World Retrospective Cohort Study.

To compare the rate of treatment discontinuation due to adverse events for telaprevir-based triple (T/PR) and pegylated interferon-alfa-2b and ribavirin (PR) therapy for the treatment of hepatitis C virus (HCV) infection in patients over the age of 65 years, in Japan. Retrospective analysis of the health data of patients over the age of 65 years treated for a HCV infection genotype 1 using T/PR or PR therapy, from 38 prefectures in Japan. The primary outcome was the rate of treatment discontinuation due to adverse events for T/PR and PR. The secondary outcome was to evaluate the prevalence and type of adverse events during the treatment period that resulted in treatment discontinuation for both therapies. For comparison, the T/PR and PR populations were matched using the propensity score method, and adjusted odds ratios (ORs) for treatment discontinuation calculated by multivariate logistic regression analysis. The study group included 1330 patients, 328 in the T/PR group and 1002 in the PR group. The rate of treatment discontinuation due to adverse events in the matched population was lower for T/PR (19.82%) than PR (35.98%) therapy, (adjusted OR, 0.418; 95% confidence interval, 0.292-0.599; p<0.01). Malaise was the principal cause of treatment discontinuation in both groups (T/PR, 30.77%, and PR, 42.37%). Using real-world health data of elderly individuals in Japan, we identified a lower rate of treatment discontinuation for T/PR than PR. Our outcomes provide information for a segment of the population that is generally excluded for clinical trials.

Pattern analysis of total item score and item response of the Kessler Screening Scale for Psychological Distress (K6) in a nationally representative sample of US adults.

BACKGROUND: Several recent studies have shown that total scores on depressive symptom measures in a general population approximate an exponential pattern except for the lower end of the distribution. Furthermore, we confirmed that the exponential pattern is present for the individual item responses on the Center for Epidemiologic Studies Depression Scale (CES-D). To confirm the reproducibility of such findings, we investigated the total score distribution and item responses of the Kessler Screening Scale for Psychological Distress (K6) in a nationally representative study. METHODS: Data were drawn from the National Survey of Midlife Development in the United States (MIDUS), which comprises four subsamples: (1) a national random digit dialing (RDD) sample, (2) oversamples from five metropolitan areas, (3) siblings of individuals from the RDD sample, and (4) a national RDD sample of twin pairs. K6 items are scored using a 5-point scale: "none of the time," "a little of the time," "some of the time," "most of the time," and "all of the time." The pattern of total score distribution and item responses were analyzed using graphical analysis and exponential regression model. RESULTS: The total score distributions of the four subsamples exhibited an exponential pattern with similar rate parameters. The item responses of the K6 approximated a linear pattern from "a little of the time" to "all of the time" on log-normal scales, while "none of the time" response was not related to this exponential pattern. DISCUSSION: The total score distribution and item responses of the K6 showed exponential patterns, consistent with other depressive symptom scales.

Cost-Outcome Description of PEG-IFN-α2b+RBV for Hepatitis C: Results Based on the Interferon Database.

Economic evaluation of drugs is used in decision-making on medical care and public policy. Recently, real-world data (RWD) have been used in the analysis. In this study, we discuss the risk and benefits of using RWD for economic evaluation. We conducted a cost-outcome description with RWD from a nationwide registry providing information on hepatitis treatment in Japan and estimated the utility of the analysis. We evaluated the cost-outcome description of peginterferon plus ribavirin (PEG-IFN-α2b+RBV) treatment in hepatitis C virus (HCV)-infected patients. Simulations were based on a Markov model. The cohorts were set using data from the registry and we assumed a societal perspective for the calculation of costs. The dose and drug cost were chosen based on the Japanese Guidelines for the Management of Hepatitis C Virus Infection or package inserts. Model details and parameters were as described in previous studies. The simulations were performed for a period of 10 years with no discount rate. We estimated 2.5 million JPY per Quality Adjusted Life Year (QALY) in 48-week PEG-IFN-α2b+RBV treatment for a period of 10 years. The results of this study are in agreement with previous HCV treatment economic evaluation studies in Japan. We analyzed the statistics of the HCV-infected patients at each disease stage using the data in our registry and calculated the costs. The results of this study more closely reflect a real-world clinical situation compared to the widely used randomized clinical trial method, which estimates clinical trial results and scenarios.

Effects of Green Tea Gargling on the Prevention of Influenza Infection: An Analysis Using Bayesian Approaches.

OBJECTIVES: The aim of this study is to analyze the data obtained from a randomized trial on the prevention of influenza by gargling with green tea, which gave nonsignificant results based on frequentist approaches, by using Bayesian approaches. METHODS: The posterior proportion, with 95% credible interval (CrI), of influenza in each group was calculated. The Bayesian index θ is the probability that a hypothesis is true. In this case, θ is the probability that the hypothesis that green tea gargling reduced influenza compared with water gargling is true. Univariate and multivariate logistic regression analyses were also performed by using the Markov chain Monte Carlo method. RESULTS: The full analysis set included 747 participants. During the study period, influenza occurred in 44 participants (5.9%). The difference between the two independent binominal proportions was -0.019 (95% CrI, -0.054 to 0.015; θ = 0.87). The partial regression coefficients in the univariate analysis were -0.35 (95% CrI, -1.00 to 0.24) with use of a uniform prior and -0.34 (95% CrI, -0.96 to 0.27) with use of a Jeffreys prior. In the multivariate analysis, the values were -0.37 (95% CrI, -0.96 to 0.30) and -0.36 (95% CrI, -1.03 to 0.21), respectively. CONCLUSIONS: The difference between the two independent binominal proportions was less than 0, and θ was greater than 0.85. Therefore, green tea gargling may slightly reduce influenza compared with water gargling. This analysis suggests that green tea gargling can be an additional preventive measure for use with other pharmaceutical and nonpharmaceutical measures and indicates the need for additional studies to confirm the effect of green tea gargling.

Relationship between Item Responses of Negative Affect Items and the Distribution of the Sum of the Item Scores in the General Population.

BACKGROUND: Several studies have shown that total depressive symptom scores in the general population approximate an exponential pattern, except for the lower end of the distribution. The Center for Epidemiologic Studies Depression Scale (CES-D) consists of 20 items, each of which may take on four scores: "rarely," "some," "occasionally," and "most of the time." Recently, we reported that the item responses for 16 negative affect items commonly exhibit exponential patterns, except for the level of "rarely," leading us to hypothesize that the item responses at the level of "rarely" may be related to the non-exponential pattern typical of the lower end of the distribution. To verify this hypothesis, we investigated how the item responses contribute to the distribution of the sum of the item scores. METHODS: Data collected from 21,040 subjects who had completed the CES-D questionnaire as part of a Japanese national survey were analyzed. To assess the item responses of negative affect items, we used a parameter r, which denotes the ratio of "rarely" to "some" in each item response. The distributions of the sum of negative affect items in various combinations were analyzed using log-normal scales and curve fitting. RESULTS: The sum of the item scores approximated an exponential pattern regardless of the combination of items, whereas, at the lower end of the distributions, there was a clear divergence between the actual data and the predicted exponential pattern. At the lower end of the distributions, the sum of the item scores with high values of r exhibited higher scores compared to those predicted from the exponential pattern, whereas the sum of the item scores with low values of r exhibited lower scores compared to those predicted. CONCLUSIONS: The distributional pattern of the sum of the item scores could be predicted from the item responses of such items.

Boundary curves of individual items in the distribution of total depressive symptom scores approximate an exponential pattern in a general population.

BACKGROUND: Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item threshold. To verify this hypothesis, we investigated the boundary curves of the distribution of total depressive symptom scores in a general population. METHODS: Data collected from 21,040 subjects who had completed the Center for Epidemiologic Studies Depression Scale (CES-D) questionnaire as part of a national Japanese survey were analyzed. The CES-D consists of 20 items (16 negative items and four positive items). The boundary curves of adjacent item scores in the distribution of total depressive symptom scores for the 16 negative items were analyzed using log-normal scales and curve fitting. RESULTS: The boundary curves of adjacent item scores for a given symptom approximated a common linear pattern on a log normal scale. Curve fitting showed that an exponential fit had a markedly higher coefficient of determination than either linear or quadratic fits. With negative affect items, the gap between the total score curve and boundary curve continuously increased with increasing total depressive symptom scores on a log-normal scale, whereas the boundary curves of positive affect items, which are not considered manifest variables of the latent trait, did not exhibit such increases in this gap. DISCUSSION: The results of the present study support the hypothesis that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores commonly follow the predicted mathematical model, which was verified to approximate an exponential mathematical pattern.

Regional Differences in Hepatitis C Treatment with Peginterferon and Ribavirin in Japan in Both Genotype 1 and Genotype 2: A Retrospective Cohort Study.

There has been no report on the genotype-dependent regional, especially prefectural, differences in hepatitis C treatment in Japan. We conducted a retrospective cohort study using the nationwide database. The registration period of the database was from December 2009 to April 2013. Individuals with chronic hepatitis C were identified from the database. The sustained virologic response (SVR) rates in each prefecture were calculated stratified by genotype. Confounding variables were identified using stepwise logistic regression analysis. The range of the point estimate of the adjusted odds ratio explained prefectural differences in treatment outcomes. During the registration period, 36 prefectures registered cases to the database. A total of 16349 cases were registered and 11653 cases were included in the analysis. The mean age was 57.9±10.5 years; 7950 (68.2%) had hepatitis C virus (HCV) genotype 1 and 3703 (31.8%) had HCV genotype 2. The range in SVR rates was 30.0 to 63.0% for genotype 1 and 55.0 to 100.0% for genotype 2. In the multivariate analysis, the ranges of the adjusted odds ratio of each prefecture were 0.658 to 2.125 for genotype 1 and 0.364 to 2.630 for genotype 2. Our results suggest that regional, particularly prefectural, differences in chronic hepatitis C treatment with peg-interferon (IFN) and ribavirin (RBV) exist in Japan and that these regional differences may similarly exist both in HCV genotypes 1 and 2. Additional studies using these methods, considering medical situations in each prefecture and new treatments regimens, could greatly contribute to improving and standardizing chronic hepatitis C treatment.