Association between physical activity and mortality in the Japanese general population with mild to moderate impaired renal function: the Jichi Medical School (JMS) cohort study.

BACKGROUND: The association between physical activity volume or intensity and mortality in general population with impaired renal function is unclear. We assessed these relationships among Japanese residents with impaired renal function. METHODS: We analyzed 638 individuals with estimated creatinine clearance below 60 ml/min in the Jichi Medical School cohort study. Exposures included the daily amount of physical activity converted to the physical activity index (PAI) used in the Framingham study and the activity time for each intensity. Physical activity intensity was classified into sedentary and nonsedentary. Nonsedentary activity was further divided into light-intensity and moderate-to-vigorous physical activity (MVPA). The outcome was all-cause mortality. Quartiles of the exposures were created, and hazard ratios (HRs) were calculated using the Cox proportional hazards model. RESULTS: The mean age of the subjects was 63.3 years, and 72.4% were female. In total, 172 deaths were registered during 11,567 person-years. No significant association was found between PAI and mortality. A significant association was found between long sedentary time and increased mortality (p = 0.042). Regarding nonsedentary activity, the HRs [95% confidence intervals (CIs)] for Q2, Q3, and Q4 versus Q1 were 0.85 (0.55-1.31), 0.67 (0.41-1.08), and 0.90 (0.54-1.45), respectively. In the subdivided analysis for light-intensity activity, the HRs (95% CIs) of Q2, Q3, and Q4 versus Q1 were 0.53 (0.33-0.84), 0.51 (0.34-0.82), and 0.57 (0.34-0.96), respectively. No significant association was found between MVPA and mortality. CONCLUSIONS: Nonsedentary activity, especially light-intensity activity, significantly reduced mortality among residents with impaired renal function.

Early detection of anastomotic leakage after esophagectomy using drain amylase levels.

BACKGROUND: Early diagnosis of anastomotic leakage (AL) after esophagectomy is essential to minimize postoperative complications. In this study, we hypothesized that drain amylase levels may be useful for early AL detection, and measuring drain amylase levels could reduce severe postoperative AL incidence. We, therefore, analyzed the usefulness of measuring drain fluid amylase levels after esophagectomy, in esophageal cancer patients. METHODS: From January 2016 to March 2020, 134 patients with esophageal cancer who underwent surgical resection with esophagogastric anastomosis in the cervical region were included. The patients were divided into a group whose cervical drain fluid amylase levels were not measured (No-AMY Group) and a group whose cervical drain fluid amylase levels were measured daily until postoperative day (POD) 7 (AMY Group). The incidence of severe AL was compared between groups. In the AMY Group, we also investigated the association between AL and drain amylase levels. RESULTS: Drain amylase levels were significantly higher in AL-positive cases than in AL-negative cases (P < 0.001). Receiver operating characteristic curve analysis revealed the drain amylase level cut-off value for AL diagnosis was 1800 U/L on POD 2 (Area under the curve = 0.835; P = 0.027). The incidence of ≥ grade III AL was significantly lower in the AMY Group than in the No-AMY Group (2 vs. 10%, P = 0.047). CONCLUSIONS: Cervical drain fluid amylase levels can be a useful screening method for early detection of AL after esophagectomy for esophageal cancer and may help reduce incidence of severe postoperative AL.

Lifetime use of complementary and alternative medicine therapies among community-dwelling older people in Japan.

[Purpose] Three complementary and alternative medicine (CAM) therapies: "Judo therapy", "acupuncture and moxibustion", and "Japanese traditional massage and finger pressure" have been partially covered by the national health insurance in Japan. The lifetime prevalence of the use of these CAM therapies is not well known. The aim of the present study was to report the prevalence of the lifetime use of these CAM therapies. [Participants and Methods] We conducted a mailed self-administered questionnaire survey among community-dwelling older people in Japan in 2015. They were asked whether they had undergone any treatments with the 3 CAM therapies. The answers obtained were classified into 3 categories: current, ever, or never. We defined lifetime prevalence as the proportion of individuals who are currently using or have ever used any of these 3 therapies in the population. [Results] Overall, we approached 1051 individuals and 983 agreed to participate. Lifetime prevalence of Judo therapy, acupuncture and moxibustion, and Japanese traditional massage and finger pressure use was 28.0%, 17.8% and 15.8%, respectively, among males, and 44.5%, 18.4%, and 27.3%, respectively, among females. [Conclusion] These results showed that not only Western medicine but also CAM therapies are common among older people in Japan.

Associations of Overweight, Obesity, and Underweight With High Serum Total Cholesterol Level Over 30 Years Among the Japanese Elderly: NIPPON DATA 80, 90, and 2010.

BACKGROUND: The trend of association between overweight and high serum total cholesterol (TC) among the elderly is unclear. In addition, there is little evidence of risk of underweight for high TC. Therefore, we examined the trend of association of overweight or underweight with high TC among Japanese elderly people using nationwide population-based data. METHODS: Data of the National Survey on Circulatory Disorders and National Health and Nutrition Survey for 1980, 1990, 2000, and 2010 were used in the analysis. High TC was defined as 220 mg/dL and above. For participants aged ≥50 years, sex-specific odds ratios (ORs) of overweight or underweight compared with normal body mass index participants for high TC were calculated using a logistic regression model adjusted for age, smoking, drinking, exercise, food, and treatment of hyperlipidemia. RESULTS: A total of 5,734, 4,673, 5,059, and 2,105 participants enrolled in these surveys in 1980, 1990, 2000, and 2010, respectively. Although overweight was positively and significantly associated with high TC in 1980, the association has gradually weakened since (ORs in 1980 and 2010 were 2.44; 95% confidence interval [CI], 1.83-3.24 and 0.92; 95% CI, 0.66-1.27 among men and 1.43; 95% CI, 1.18-1.72 and 1.08; 95% CI, 0.81-1.44 among women, respectively). While underweight was inversely and significantly associated with high TC in 1980, the association also gradually weakened among women (ORs in 1980 and 2010 were 0.28; 95% CI, 0.12-0.60 and 0.37; 95% CI, 0.10-1.28 among men and 0.39; 95% CI, 0.26-0.57 and 0.96; 95% CI, 0.58-1.57 among women, respectively). CONCLUSIONS: These findings provide evidence that high TC prevention efforts must expand the target to not only overweight but also to normal and underweight people.

Coping behaviors for skeletal muscle injuries and disorders among community-dwelling elderly persons in Japan.

[Purpose] This study aimed to determine the coping behaviors of elderly Japanese community-dwelling persons toward their skeletal muscle injuries and disorders. [Participants and Methods] A mail-in, self-administered questionnaire survey was administered to 1,084 community-dwelling adults aged 70 years and older. Information was obtained regarding their coping behaviors when dealing with bone fractures, dislocations, sprains, bruising, stiff shoulders, low back pain, acute muscle/joint pain, chronic muscle/joint pain, and daily fatigue. [Results] Visits to hospitals or general clinics were the most popular coping behavior for bone fractures, dislocations, sprains, bruising, low back pain, acute muscle/joint pain, and chronic muscle/joint pain; visits to a Judo therapist's office were the second most popular coping behavior for these conditions. Acupuncture, as well as chiropractic and massage clinics, were less frequently visited. For stiff shoulders and daily fatigue, many participants did not visit any medical facility. [Conclusion] Among the elderly, visits to hospitals or general clinics were the most used coping behavior for many types of skeletal muscle injuries and disorders. Visits to a Judo therapist's office were the second most used coping behavior. Visits to acupuncture, chiropractic, and massage clinics were less frequent. With these data, therapists could improve their care skills upon consideration of the coping preferences among community-dwelling elderly persons.

Orthopedic, ophthalmic, and psychiatric diseases primarily affect activity limitation for Japanese males and females: Based on the Comprehensive Survey of Living Conditions.

BACKGROUND: Healthy life expectancy (HLE) is used as one of the primary objectives of fundamental health promotion plans and social development plans. Activity limitation is used to calculate HLE, but little study has been done to identify determinants of activity limitation in order to extend HLE. The purpose of this study is to identify diseases and injuries that commonly lead to activity limitation to prioritize countermeasures against activity limitation. METHODS: We used anonymous data from the 2007 "Comprehensive Survey of Living Conditions," collected by the Ministry of Health, Labour and Welfare of Japan according to the Statistics Act, Article 36. We used logistic regression analyses and calculated odds ratios (ORs) after adjusting for age and sex. Limitation in daily activities was applied as the dependent variable, and each disease/injury was applied as an independent variable in this analysis. Furthermore, population attributable fractions (PAFs) were calculated. RESULTS: The provided data included 98,789 subjects. We used data for 75,986 valid subjects aged 12 years or older. The following diseases showed high PAF: backache (PAF 13.27%, OR 3.88), arthropathia (PAF 7.61%, OR 4.82), eye and optical diseases (PAF 6.39%, OR 2.01), and depression and other mental diseases (PAF 5.70%, OR 11.55). PAFs of cerebrovascular diseases, hypertension, and diabetes were higher for males than for females; on the other hand, PAFs of orthopedic diseases were higher among females. CONCLUSIONS: Our results indicate that orthopedic diseases, ophthalmic diseases, and psychiatric diseases particularly affect activity limitation.

Retroperitoneal low-grade fibromyxoid sarcoma.

Introduction: Low-grade fibromyxoid sarcoma is an uncommon deep-seated soft-tissue sarcoma that occurs rarely in young adults and children. Although surgical resection provides a long-term prognosis, late local recurrence and metastasis may occur. Case presentation: A 44-year-old woman with no prior medical history presented with breathing and abdominal discomfort. Contrast-enhanced computed tomography scan revealed a retroperitoneal tumor protruding into the thoracic cavity and pleural effusion on the left side. Tumor biopsy revealed sarcoma. We performed complete resection of the tumor along with part of the diaphragm and replaced the diaphragm with a prosthetic patch. Histopathologic findings indicated low-grade fibromyxoid sarcoma. The patient experienced no postoperative complications and received no adjuvant therapy. Furthermore, she survived 4 years after surgery without recurrence. Conclusion: Complete surgical resection is effective for low-grade fibromyxoid sarcoma; therefore, it is important to plan appropriately for complete resection when biopsy reveals malignant findings.

The Validation of the Japanese Version of the Scoliosis Research Society-30 Questionnaire for Adolescent Idiopathic Scoliosis Patients.

Introduction: The Scoliosis Research Society-30 (SRS-30) is a questionnaire originally developed from the SRS-22r questionnaire and is used to evaluate adolescent idiopathic scoliosis (AIS). It comprised questions on five domains: function, pain, self-image, mental health, and satisfaction, with seven additional questions related to postoperative aspects. In addition to the original English version, translations in multiple languages have been effectively applied. Herein, we evaluated the internal consistency and external validity of the Japanese version of the SRS-30 for AIS patients. Methods: Among the 30 questions in SRS-30, the eight additional questions from SRS-22r were translated and back-translated to create a Japanese version of the SRS-30. This translated questionnaire was then used to survey patients with AIS who underwent corrective fusion surgery one year postoperatively. The internal consistency of the responses was evaluated using the Cronbach α coefficient. Additionally, the Spearman correlation analyses were conducted to assess the correlation between the scores obtained from the SRS-30 Japanese version and SRS-22r and the Oswestry Disability Index (ODI) for the overall scale and the five domains. Results: A total of 81 cases (eight males and 73 females; mean age at surgery 14.4 years) were enrolled. The mean preoperative Cobb angle was 51.0°. The Cronbach α coefficient for the overall SRS-30 was 0.861, indicating high internal consistency, while the coefficients for each domain were as follows: function/activity, 0.697; pain, 0.405; self-image/appearance, 0.776; mental health, 0.845; and satisfaction, 0.559. The SRS-30 total score significantly correlated with the SRS-22r total (r=0.945, P<0.001) and the ODI (r=-0.511, P<0.001). The SRS-30 domains highly correlated with the corresponding SRS-22r domains, with correlations ranging from r=0.826 to 0.901 (all P<0.001). Conclusions: The Japanese version of the SRS-30 demonstrated good internal and external validity. The SRS-30 can be used as an assessment tool for health-related quality of life in AIS patients.

Prevalence and the Influence of Trapeziometacarpal Osteoarthritis on Patients with Carpal Tunnel Syndrome.

Background: The coexistence of carpal tunnel syndrome (CTS) and trapeziometacarpal (TMC) osteoarthritis have been previously described. The influence of TMC osteoarthritis in the outcomes of CTS surgery is yet to be elucidated. The purpose of this study is to examine the prevalence of TMC osteoarthritis in patients who underwent open carpal tunnel release (OCTR) and to analyse the influence of osteoarthritis on the postoperative outcomes of CTS. Methods: We retrospectively reviewed 134 procedures on 113 patients who underwent OCTR between 2002 and 2017. The presence of TMC osteoarthritis was based upon preoperative plain radiograph. For the evaluation of CTS, pre- and postoperative muscle power of abductor pollicis brevis (APB) muscle by manual muscle testing (MMT) and distal motor latency (DML) detected on the APB muscle was examined. Results: The mean follow-up period was 11.4 months. The prevalence of radiographic TMC osteoarthritis was 40% in patients who underwent OCTR. In electrophysiological study, the mean pre- and postoperative DML showed no statistical difference regardless of the coexistence of TMC osteoarthritis. However, there was a significantly higher incidence of poorer muscle strength of the APB in patients with TMC osteoarthritis. No patients complained of TMC joint pain prior to OCTR, but four cases developed TMC joint pain during the postoperative follow-up period, all of whom had full recovery of APB muscle strength. Conclusions: The presence of asymptomatic TMC osteoarthritis may affect the postoperative outcomes of OCTR, so preoperative evaluation of TMC osteoarthritis should be considered in patients undergoing OCTR. In addition, the symptoms of TMC osteoarthritis may worsen in some patients after CTS surgery and should be taken into consideration during the postoperative follow-up. Level of Evidence: Level IV (Therapeutic).

Immune mediators as predictive biomarkers for anti-PD-1 antibody therapy in urothelial carcinoma.

Introduction: This study aimed to identify immune mediators, including cytokines, chemokines, and growth factors, in the plasma for predicting treatment efficacy and immune-related adverse events (irAEs) in advanced urothelial carcinoma (aUC) treated with immune checkpoint inhibitors (ICIs). Methods: We enrolled 57 patients with aUC who were treated with the anti-programmed cell death protein 1 (PD-1) antibody pembrolizumab after the failure of platinum-based chemotherapy between February 2018 and December 2020. Plasma levels of 73 soluble immune mediators were measured before and 6 weeks after initiating pembrolizumab therapy. The association of estimated soluble immune mediators with clinical outcomes, including overall survival (OS), progression-free survival (PFS), anti-tumor responses, and irAEs, were statistically evaluated. Results: In the multivariate analysis, levels of 18 factors at baseline and 12 factors during treatment were significantly associated with OS. Regarding PFS, baseline levels of 17 factors were significantly associated with PFS. Higher levels of interleukin (IL)-6, IL-8, soluble tumor necrosis factor receptor 1 (sTNF-R1), and IL-12 (p40), both at baseline and post-treatment, were significantly associated with worse OS. Conversely, low IL-6 and high TWEAK levels at baseline were associated with irAEs. Among identified factors, interferon (IFN) γ and IL-12 (p40) were repeatedly identified; high baseline levels of these factors were risk factors for worse OS and PFS, as well as progressive disease. Notably, using correlation and principal component analysis, factors significantly associated with clinical outcomes were broadly classified into three groups exhibiting similar expression patterns. Discussion: Measuring plasma levels of soluble immune mediators, such as IL-6, IL-8, sTNF-R1, IFNγ, and IL-12 (p40), could be recommended for predicting prognosis and irAEs in ICI-treated patients with aUC.

Frequency of Change in Assessment from Bony Union to Nonunion after Lumbar Interbody Fusion: A Multicenter Study.

INTRODUCTION: Assessments of early postoperative bony union after posterior lumbar interbody fusion via computed tomography (CT) have revealed cases in which interbody fixation by bony union resulted in nonfusion due to bone absorption. The apparent bone union state reverted to a nonunion state several months later, exhibiting a so-called "fake union" phenomenon. Additionally, few reports have evaluated the effect of teriparatide on bony union. The present study aimed to evaluate the frequency of change in assessment from fusion to nonfusion in the postoperative follow-up of lumbar interbody fusion, compare the late postoperative bony union rates in groups with or without early postoperative fusion, and examine the effect of postoperative teriparatide in those groups. METHODS: Sixty-nine subjects enrolled from multiple hospitals were prospectively evaluated following single-level lumbar interbody fusion. The patients were randomly allocated into treatment with or without weekly postoperative teriparatide. The subjects were then classified as having bony union or nonfusion at 2 months postoperatively, and fusion rates at 6 months were compared. For the evaluation of bony union, blinded radiological examinations were performed via CT. Additional comparisons were made according to teriparatide use. RESULTS: The rate of nonunion at 6 months postoperatively in patients with fusion at 2 months postoperatively was 27.8%. Among subjects with bony union at 2 months postoperatively, the fusion rate at 6 months in those who received teriparatide was 93.3% (p=0.027) versus 57.1% in those who did not. CONCLUSIONS: The rate of nonunion at 6 months postoperatively in patients exhibiting union at 2 months after surgery was 27.8%. Postoperative weekly teriparatide treatment significantly reduced the rate of fake union.

Impact of Early Intervertebral Osseous Union After Posterior Lumbar Interbody Fusion on Health-Related Quality of Life.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Nonunion after posterior lumbar interbody fusion (PLIF) is associated with poor improvements in health-related quality of life (HRQOL). We aimed to investigate the influence of early osseous union after PLIF on HRQOL. METHODS: We reviewed 138 patients with 1-level PLIF (mean age 67 years, follow-up period ≥1 year). Postoperative lumbar computed tomography was performed to assess screw loosening and intervertebral union. HRQOL was assessed using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. RESULTS: Thirty-nine patients (28%) showed complete union at 6 months postoperatively (early union group). Twenty-eight patients (20%) showed complete union at 6 to 12 months postoperatively (delayed union group), while 71 patients demonstrated noncomplete union. Effective improvement of lumbar spine dysfunction and psychological disorders was achieved in 19 (63.3%) and 17 (50.0%) patients in the early union group, in 9 (42.9%) and 14 (53.8%) patients in the delayed union group, and in 22 (34.9%) and 19 (29.2%) patients in the nonunion group, respectively (P = .036 and P = .036, respectively). The nonunion group had a significantly higher proportion of cases with screw loosening at 6 and 12 months postoperatively than the complete union group (P = .033 and P = .022). CONCLUSIONS: Lumbar spine dysfunction and psychological disorders improved in cases with early complete union compared to those with nonunion. Screw loosening occurred in cases with nonunion predominantly from 6 months postoperatively. Therefore, the achievement of early complete union might be helpful for better HRQOL and lower incidence of postoperative complications.

Physical activity and risk of fatal or non-fatal cardiovascular disease among CVD survivors: the JMS cohort study.

BACKGROUND: Although many population-based studies have reported an association between physical activity and cardiovascular disease (CVD) among healthy populations, the association among CVD survivors has been less reported. We examined the relationship between physical activity and CVD risk among survivors. METHODS AND RESULTS: This was a prospective cohort study of 12,490 Japanese participants, including 754 individual CVD survivors. Between April 1992 and July 1995, a baseline survey was conducted in 12 communities in Japan. The mean follow-up period was 11.9 years, during which time 74 individuals had non-fatal CVD and 51 cases were fatal CVD. Among CVD survivors, analysis was performed after exclusion of participants with a history of cancer and those who died within the first 2 years of follow-up. Physical activity was analyzed in tertiles (low, moderate and heavy), and the hazard ratios (HRs) were calculated for non-fatal or fatal CVD among CVD survivors. After setting the low group as the reference, the HRs for non-fatal CVD in the moderate and heavy groups were 0.61 (95% confidence interval: 0.30-1.24) and 0.50 (0.20-1.25) (P for trend = 0.059), respectively, and the HRs for fatal CVD were 0.75 (0.33-1.69) and 0.18 (0.04-0.83) (P for trend = 0.026), respectively. CONCLUSIONS: Physical activity reduced the risk of CVD, both fatal and non-fatal events, among CVD survivors.

Incidence of symptoms and accidents during baths and showers among the Japanese general public.

BACKGROUND: Bathing is a deeply ingrained custom among Japanese; however, data on the incidence rate of symptoms and accidents during bathing have not yet been reported for the Japanese general public. METHODS: We conducted a population-based cross-sectional study of 617 Japanese adults who attended a specialized health checkup. Participants completed a self-administered questionnaire to assess weekly frequencies of bathtub bathing and showering and the frequency of symptoms/accidents (falling, loss of consciousness, and other) during these activities in the past year. We calculated the incidence rates of accidents per 10 000 baths/showers and 95% confidence intervals (CIs) and compared the clinical characteristics of participants who had symptoms/accidents with those who did not. RESULTS: The incidence rates of accidents per 10 000 bathtub baths and showers were 0.43 (95% CI: 0.22-0.84) and 0.24 (95% CI: 0.04-1.37). Although these rates are low, there were 740 000 bathtub bathing-related accidents in Japan, due to the fact that bathing is an almost-daily habit. There was no significant difference in clinical characteristics between groups. CONCLUSIONS: We collected basic information on the incidence of bathing-related accidents in Japan. Falls and loss of consciousness during bathing or showering can potentially lead to a serious accident, so the general public should be educated about the possibility of such accidents during bathing.

Frequency of citrus fruit intake is associated with the incidence of cardiovascular disease: the Jichi Medical School cohort study.

BACKGROUND: It has been reported that fruit intake protects against cardiovascular disease (CVD). However, most of the relevant studies were conducted in Western countries, and only a few investigated Japanese populations. The present cohort study assessed the effect of citrus fruit intake on the incidence of CVD and its subtypes in a Japanese population. METHODS: A baseline examination consisting of physical and blood examinations and a self-administered questionnaire was conducted during the period from April 1992 through July 1995. Dietary habits were assessed using a food frequency questionnaire that was divided into 5 categories. Citrus fruit was examined separately due to its frequent consumption by the general Japanese population. Using the Cox proportional hazards model, data from 10,623 participants (4147 men, 6476 women) who had no history of CVD or carcinoma were analyzed to assess the association between frequency of citrus fruit intake and CVD incidence. RESULTS: Frequent intake of citrus fruit was associated with a lower incidence of CVD: the hazard ratio for almost daily intake versus infrequent intake of citrus fruit was 0.57 (95% confidence interval: 0.33-1.01, P for trend = 0.04) in men and 0.51 (0.29-0.88, P for trend = 0.02) in women. Frequent intake of citrus fruit was also associated with lower incidences of both all stroke and cerebral infarction, but not hemorrhagic stroke or myocardial infarction. CONCLUSIONS: Frequent intake of citrus fruit may reduce the incidence of CVD, especially cerebral infarction, in men and women.

Re-Challenging with Nivolumab in Metastatic Renal Cell Carcinoma After Immune-Related Interstitial Pneumonia: A Case Report.

BACKGROUND The efficacy and safety of re-challenge with immune checkpoint inhibitors after immune-related adverse events have not been established. We report a case of successful re-administration of nivolumab in metastatic renal cell carcinoma after discontinuation due to immune-related adverse events. CASE REPORT Laparoscopic nephrectomy was performed on a 52-year-old man diagnosed with renal cell carcinoma pT1bN0M0. After surgery, left adrenal and lung metastases appeared. Nivolumab was administered as a sixth-line therapy, and he achieved a partial response, but interstitial pneumonia occurred. He was diagnosed with grade 2 immune-related adverse events, and nivolumab treatment was discontinued. Interstitial pneumonia was well controlled by steroids. He maintained a partial response for a long time, and the lung metastases disappeared 7 months after discontinuation. However, bilateral lung metastases reappeared 10 months after the discontinuation. We decided to re-administer nivolumab, while carefully monitoring the patient and fully explaining the risk of recurrence of immune-related adverse events. After 5 cycles of re-administration, computed tomography revealed a reduction in metastases without re-activation of interstitial pneumonia. He experienced a grade 1 fever the day after re-administration, but continued nivolumab therapy without other adverse events. After 7 cycles of re-administration, the lung metastases increased, and nivolumab treatment was terminated. Two months later, a grade 2 interstitial pneumonia recurred, but improved rapidly with oral steroids. CONCLUSIONS For patients who have discontinued immune checkpoint inhibitors due to immune-related adverse events, re-challenge of immune checkpoint inhibitors may be an option after explaining the risk of relapse of immune-related adverse events.

Physical activity and cardiovascular disease in Japan: the Jichi Medical School Cohort Study.

BACKGROUND: Many studies have reported an association between physical activity and cardiovascular disease (CVD); however, the effect of physical activity remains controversial. Few such studies have been conducted in Japan. Therefore, we examined the relationship between physical activity and death from CVD using prospective data from a Japanese population. METHODS: From a prospective cohort study that comprised 12 490 participants, data from 9810 were analyzed. From April 1992 through July 1995, a baseline survey was conducted in 12 communities in Japan. The participants were followed up until December 2005. Physical activity was assessed using the physical activity index (PAI). PAI scores were grouped in quartiles: Q1 was the lowest PAI quartile and Q4 was the highest. Hazard ratios (HRs) for death from CVD, stroke, and myocardial infarction (MI) were calculated for all PAI quartiles. RESULTS: The mean follow-up period was 11.9 years, during which time 194 participants died of CVD. With Q1 as the reference, the HRs for death from CVD in Q2, Q3, and Q4, were 0.62 (95% confidence interval, 0.40-0.98), 0.53 (0.31-0.88), and 0.40 (0.22-0.73), respectively, in men, and 0.71 (0.38-1.32), 0.52 (0.26-1.04), and 0.48 (0.22-1.05), respectively, in women. The HRs for death from CVD subtypes were similar but not statistically significant. CONCLUSIONS: Among a Japanese population, physical activity was associated with a decreased risk of death from CVD. However, more evidence is needed to elucidate the relationships between physical activity and CVD subtypes.

The Titanium-coated PEEK Cage Maintains Better Bone Fusion With the Endplate Than the PEEK Cage 6 Months After PLIF Surgery: A Multicenter, Prospective, Randomized Study.

STUDY DESIGN: A multicenter, randomized, open-label, parallel-group trial. OBJECTIVE: To investigate interbody bone fusion rates in titanium-coated polyetheretherketone (TiPEEK) and polyetheretherketone (PEEK) cages after posterior lumbar interbody fusion (PLIF) surgery. SUMMARY OF BACKGROUND DATA: Previous clinical studies have not revealed any significant difference in bone fusion rates between TiPEEK and PEEK cages. METHODS: During one-level PLIF surgery, 149 patients (84 men, 65 women, mean age 67 yr) were randomly allocated to use either a TiPEEK cage (n = 69) or PEEK cage (n = 80). Blinded radiographic evaluations were performed using computed tomography and assessed by modified intention-to-treat analysis in 149 cases and per-protocol analysis in 143 cases who were followed for 12 months. Clinical outcomes were assessed using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and the Oswestry Disability Index. RESULTS: The interbody union rate at 12 months after surgery was 45% owing to a very strict definition of bone fusion. The rates of bone fusion were significantly higher at 4 and 6 months after surgery in the TiPEEK group than in the PEEK group in the unadjusted modified intention-to-treat analysis and were significantly higher at 6 months in the unadjusted per-protocol analysis. Binary logistic regression analysis adjusted for sex, age, body mass index, bone mineral density, and surgical level showed that using a TiPEEK cage (odds ratio, 2.27; 95% confidence interval: 1.09-4.74; P = 0.03) was independently associated with bone fusion at 6 months after surgery. Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and Oswestry Disability Index results improved postoperatively in both groups. CONCLUSION: Using the TiPEEK cage for PLIF enabled the maintenance of better bone fusion to the endplate than using the PEEK cage at 6 months after the surgery. Our findings suggest the possibility of an earlier return to rigorous work or sports by the use of TiPEEK cage. LEVEL OF EVIDENCE: 1.

Impact of sufficient contact between the autograft and endplate soon after surgery to prevent nonunion at 12 months following posterior lumbar interbody fusion.

OBJECTIVE: Nonunion after posterior lumbar interbody fusion (PLIF) is associated with poor long-term outcomes in terms of health-related quality of life. Biomechanical factors in the fusion segment may influence spinal fusion rates. There are no reports on the relationship between intervertebral union and the absorption of autografts or vertebral endplates. Therefore, the purpose of this retrospective study was to evaluate the risk factors of nonunion after PLIF and identify preventive measures. METHODS: The authors analyzed 138 patients who underwent 1-level PLIF between 2016 and 2018 (75 males, 63 females; mean age 67 years; minimum follow-up period 12 months). Lumbar CT images obtained soon after the surgery and at 6 and 12 months of follow-up were examined for the mean total occupancy rate of the autograft, presence of a translucent zone between the autograft and endplate (more than 50% of vertebral diameter), cage subsidence, and screw loosening. Complete intervertebral union was defined as the presence of both upper and lower complete fusion in the center cage regions on coronal and sagittal CT slices at 12 months postoperatively. Patients were classified into either union or nonunion groups. RESULTS: Complete union after PLIF was observed in 62 patients (45%), while nonunion was observed in 76 patients (55%). The mean total occupancy rate of the autograft immediately after the surgery was higher in the union group than in the nonunion group (59% vs 53%; p = 0.046). At 12 months postoperatively, the total occupancy rate of the autograft had decreased by 5.4% in the union group and by 11.9% in the nonunion group (p = 0.020). A translucent zone between the autograft and endplate immediately after the surgery was observed in 14 and 38 patients (23% and 50%) in the union and nonunion groups, respectively (p = 0.001). The nonunion group had a significantly higher proportion of cases with cage subsidence and screw loosening at 12 months postoperatively in comparison to the union group (p = 0.010 and p = 0.009, respectively). CONCLUSIONS: A lower occupancy rate of the autograft and the presence of a translucent zone between the autograft and endplate immediately after the surgery were associated with nonunion at 12 months after PLIF. It may be important to achieve sufficient contact between the autograft and endplate intraoperatively for osseous union enhancement and to avoid excessive absorption of the autograft. The achievement of complete intervertebral union may decrease the incidence of cage subsidence or screw loosening.