Sarcopenia phenotype and impaired muscle function in male mice with fast-twitch muscle-specific knockout of the androgen receptor.

Sarcopenia is distinct from normal muscle atrophy in that it is closely related to a shift in the muscle fiber type. Deficiency of the anabolic action of androgen on skeletal muscles is associated with sarcopenia; however, the function of the androgen receptor (AR) pathway in sarcopenia remains poorly understood. We generated a mouse model (fast-twitch muscle-specific AR knockout [fmARKO] mice) in which the AR was selectively deleted in the fast-twitch muscle fibers. In young male mice, the deletion caused no change in muscle mass, but it reduced muscle strength and fatigue resistance and induced a shift in the soleus muscles from fast-twitch fibers to slow-twitch fibers (14% increase, P = 0.02). After middle age, with the control mice, the male fmARKO mice showed much less muscle function, accompanied by lower hindlimb muscle mass; this phenotype was similar to the progression of sarcopenia. The bone mineral density of the femur was significantly reduced in the fmARKO mice, indicating possible osteosarcopenia. Microarray and gene ontology analyses revealed that in male fmARKO mice, there was downregulation of polyamine biosynthesis-related geneswhich was confirmed by liquid chromatography-tandem mass spectrometry assay and the primary cultured myofibers. None of the AR deletion-related phenotypes were observed in female fmARKO mice. Our findings showed that the AR pathway had essential muscle type- and sex-specific roles in the differentiation toward fast-twitch fibers and in the maintenance of muscle composition and function. The AR in fast-twitch muscles was the dominant regulator of muscle fiber-type composition and muscle function, including the muscle-bone relationship.

Early-onset dementia and risk of hip fracture and major osteoporotic fractures.

INTRODUCTION: There is limited knowledge about early-onset dementia (EOD) on fracture risk. METHODS: Individuals ages 50 to 64 were identified from the National Database of Health Insurance Claims and Specific Health Checkups of Japan (2012 to 2019). The association between EOD and fractures and the association between cholinesterase inhibitors for EOD and fractures were evaluated using logistic regression analyses. RESULTS: We identified 13,614 EOD patients and 9,144,560 cognitively healthy individuals. The analysis revealed that EOD was associated with an increased risk of hip fractures (adjusted odds ratio, 95% confidence interval: 8.79, 7.37-10.48), vertebral fractures (1.73, 1.48-2.01), and major osteoporotic fractures (2.05, 1.83-2.30) over 3 years. The use of cholinesterase inhibitors was significantly associated with a reduction in hip fractures among EOD patients (0.28, 0.11-0.69). DISCUSSION: EOD patients have a higher risk of osteoporotic fractures than cognitively healthy individuals. The use of cholinesterase inhibitors may reduce the risk of hip fracture among EOD patients. HIGHLIGHTS: It is unknown whether early-onset dementia (EOD) increases the risk of fractures. We identified 13,614 individuals with EOD using a nationwide administrative database. Patients with EOD have a higher risk of hip, vertebral, and major osteoporotic fractures. The use of cholinesterase inhibitors may reduce hip fracture among patients with EOD.

The roles of sex hormones in the pathophysiology of age-related sarcopenia and frailty.

Background: Sarcopenia is an age-related condition characterized by a progressive and systemic decline in skeletal muscle mass, quality, and strength. The incidence of sarcopenia contains sex-specific aspects, indicating the contribution of sex hormones to its pathophysiology. This review focuses on changing trends in sarcopenia, discusses alterations in definitions and diagnostic criteria, and emphasizes the association between sarcopenia and sex hormones. Methods: A literature search was performed on PubMed for related articles published between 1997 and December 2023 using appropriate keywords. Main Findings Results: Advances in research have emphasized the significance of muscle quality and strength over muscle mass, resulting in new diagnostic criteria for sarcopenia. Androgens demonstrated anabolic effects on skeletal muscles and played a significant role in the pathophysiology of sarcopenia. In clinical settings, androgen replacement therapy has exhibited certain positive outcomes for treating sarcopenia, despite concerns about potential side effects. Conversely, estrogen is involved in skeletal muscle maintenance, but the detailed mechanisms remain unclear. Moreover, results regarding the clinical application of estrogen replacement therapy for treating sarcopenia remained inconsistent. Conclusion: The elucidation of molecular mechanisms that involve sex hormones is eagerly awaited for novel therapeutic interventions for sarcopenia.

Validation of the questionnaire for medical checkup of old-old (QMCOO) score cutoff to diagnose frailty.

BACKGROUND: Frailty is a state of increased vulnerability to poor resolution of homeostasis following a stress. Early diagnosis and intervention of frailty are essential to prevent its adverse outcomes. However, simple diagnostic criteria have not been established. The Questionnaire for Medical Checkup of Old-Old (QMCOO) is widely used for medical checkups of older adults in Japan. In our previous report, we developed a method to score the QMCOO and showed that frailty can be diagnosed with the highest accuracy when the score cutoff was set at 3/4 points. We aimed to validate the criteria in a larger cohort. METHODS: Participants aged 65 years or over were recruited in the western region of Japan. They answered all the items of the Kihon Checklist (KCL) and the QMCOO. Based on the KCL score, they were diagnosed as robust (3 or lower), prefrail (4 to 7), or frail (8 or over). Then we tested the effectiveness to diagnose frailty using the QMCOO cutoff of 3/4 points. We also aimed to determine the score cutoff to separate robust and prefrail. RESULTS: 7,605 participants (3,458 males and 4,147 females, age 77.4 ± 6.9 years) were recruited. 3,665 participants were diagnosed as robust, 2,448 were prefrail, and 1,492 were frail based on the KCL score. The diagnosis of frailty had a sensitivity of 84.0%, specificity of 82.5%, and accuracy of 82.8% with a QMCOO score cutoff of 3/4 points, suggesting its validity. To separate robust and prefrail, both the accuracy and the Youden index were the highest with the QMCOO cutoff of 2/3 points (sensitivity, specificity, and accuracy were 63.9%, 83.4%, and 75.6%, respectively). All the questions of the QMCOO except Q12 (about smoking) were significantly related to prefrailty status after a logistic regression analysis. CONCLUSION: Diagnosis of frailty using the QMCOO score cutoff of 3/4 points was validated. Prefrailty could be diagnosed using the score cutoff of 2/3 points.

Updated concept of sarcopenia based on muscle-bone relationship.

Sarcopenia is an age-related loss of skeletal muscle mass and strength. It has been widely recognized that low muscle mass was essential in the diagnosis of sarcopenia, whereas recent studies have emphasized the importance of muscle strength. In practice, muscle quality as well as muscle mass might determine the strength and physical performance. A new diagnostic algorithm of sarcopenia has recently been established, in which low muscle strength is a key characteristic factor for the diagnosis of sarcopenia. Although many factors are supposed to be involved in the pathology and development of sarcopenia, precise mechanisms remain to be elucidated. Recent studies have also focused on the crosstalk between muscles and bones, including functional involvement of myokines and osteokines.

Implementation status of comprehensive geriatric assessment among older inpatients: A nationwide retrospective study.

AIM: The importance of comprehensive geriatric assessment (CGA) is increasing in aging societies worldwide. However, there are few comprehensive studies on CGA, resulting in a limited understanding of its implementation rate, temporal changes and factors associated with its implementation. We aimed to investigate the implementation status of CGA and its regional variance in Japan. METHODS: Using the Diagnosis Procedure Combination database, we investigated CGA trends, and identified the patient, hospital and regional factors associated with its implementation. We identified patients aged ≥65 years who were admitted for the first time between 2016 and 2020 with a diagnosis of stroke, heart failure, pneumonia, bone fracture or colorectal cancer. We examined the CGA implementation rate according to patient and hospital characteristics. We also investigated temporal changes and tendencies to carry out CGA in different prefectures. RESULTS: A total of 1 974 817 patients were analyzed, of whom 570 696 (28.9%) underwent CGA. The implementation trend increased steadily from 25.3% in fiscal year 2016 to 33.4% in fiscal year 2019. The implementation rate also increased with patient age (30.3% in patients aged ≥95 years). Regional variations in its implementation status were observed, with a higher tendency to be implemented in areas near major metropolitan regions. A trend toward carrying out CGA for colorectal cancer, but not for other diseases, has been observed in eastern Japan. CONCLUSION: Although CGA is increasingly carried out, considerable regional differences remain in its implementation status. Initiatives to reduce variations are necessary. Geriatr Gerontol Int 2024; ••: ••-••.

Exercise-induced vitamin D receptor and androgen receptor mediate inhibition of IL-6 and STAT3 in muscle.

Background: Skeletal muscle produces interleukin-6 (IL-6) during exercise as a myokine. Although IL-6 is required for skeletal muscle regeneration, its action increases the expression of myostatin and other proteins involved in muscle atrophy, resulting in skeletal muscle atrophy. In this study, we clarified the effects exercise-induced vitamin D receptor (VDR) and androgen receptor (AR) expression on IL-6 and signal transducer and activator of transcription 3 (STAT3) in vivo and in vitro. Method: C2C12 myotubes were subjected to electric pulse stimulation (EPS) in vitro. To evaluate VDR and AR function, a VDR/AR agonist and antagonist were administered before EPS to C2C12 myotubes. C57BL6 mice underwent 4 weeks of exercise. The expression levels of proteolytic-associated genes, including CCAAT/enhancer-binding protein delta (C/EBPδ) and myostatin, were measured by quantitative real-time polymerase chain reaction, and phosphorylated and total STAT3 levels were measured by Western blot analysis. Result: The expression of VDR and AR mRNA was induced following EPS in C2C12 myotubes. IL-6 mRNA expression was also increased with a peak at 6 h after EPS and p-STAT3/STAT3 ratio reciprocally decreased. Although VDR/AR agonist administration decreased IL-6 mRNA expression and p-STAT3/STAT3 ratio, these two endpoints increased after treatment with VDR/AR antagonist, respectively. Exercise in mice also increased the expression of VDR/AR and IL-6 mRNA and decreased p-STAT3/STAT3 ratio. Conclusion: Exercise-induced VDR and AR expression results in the suppression of IL-6 mRNA and STAT3 phosphorylation in skeletal muscle.

Relationship between donepezil and fracture risk in patients with dementia with Lewy bodies.

AIM: Patients with dementia with Lewy bodies (DLB) are at a high risk for falls and fractures. Although cholinesterase inhibitors reportedly are effective in suppressing the progression of cognitive symptoms in DLB patients, their effects on fracture risk remain unclarified. This study aimed to evaluate the association between donepezil use and hip fracture risk in older patients with DLB. METHODS: Using the Japanese insurance claim database, we collected the data of patients aged ≥65 years with DLB from April 2012 to March 2019. After propensity score matching, we compared the fracture rate over 3 years between DLB patients receiving donepezil and those not receiving antidementia drugs. RESULTS: Altogether, 24 022 239 individuals aged ≥65 years were newly registered from April 2012 to March 2016 and had verifiable information from 6 months before to 3 years after the registration. We identified 6634 pure-DLB patients and analyzed the data of 1182 propensity score-matched pairs. The characteristics, including age, sex, fracture history, osteoporosis, and bone mineral density test rate, of the two groups were well balanced by propensity score matching. The incidence rate of hip fracture was significantly lower in DLB patients receiving donepezil than in those not receiving antidementia drugs (0.60 vs. 1.44/100 person-years, P < 0.001), whereas that of vertebral fractures was the same. CONCLUSIONS: Donepezil administration in Japanese people aged ≥65 years with DLB was significantly associated with a decreased risk of hip fracture. Donepezil may provide new benefits to DLB patients. Geriatr Gerontol Int 2024; 24: 782-788.

Effect of a Financial Incentive Scheme for Medication Review on Polypharmacy in Elderly Inpatients With Dementia: A Retrospective Before-and-After Study.

OBJECTIVES: Polypharmacy is an important healthcare issue, especially in elderly patients with dementia. As an incentive to reduce polypharmacy, a health insurance reimbursement scheme was introduced in 2016 for medication review and the reduction of medications for inpatients in Japan. However, the effects of these incentive schemes were not evaluated. METHODS: We identified 1,465,881 inpatients aged ≥65 years with dementia. An interrupted time-series analysis was conducted by fitting a Prais-Winsten linear regression model. The outcome measure was the number of classes of medications prescribed during discharge. RESULTS: No significant changes were observed in the average number of medication classes at discharge immediately after the introduction of the scheme (coefficient: -0.022, 95% confidence interval [CI]: -0.17 to 0.13). The slope change, representing the effect of the intervention over time, was also not significant (coefficient: -0.00053, 95% confidence interval: -0.0012 to 0.00018). CONCLUSIONS: The incentive scheme was not associated with a reduction in the number of medication classes at discharge among older inpatients with dementia.

Relationship between antidementia medication and fracture prevention in patients with Alzheimer's dementia using a nationwide health insurance claims database.

This retrospective study aimed to evaluate the association between antidementia medication use and incidence of new vertebral, hip, and radial fractures in patients with Alzheimer's dementia (AD). We used the nationwide health insurance claims database of Japan from 2012 to 2019 and identified 12,167,938 patients aged ≥ 65 years who were newly registered from April 2012 to March 2016 and had verifiable data receipt from half-year before to 3 years after the registration. Among these patients, 304,658 were diagnosed with AD and we showed the prescription status of antidementia and osteoporosis medication among them. Propensity score matching was conducted for AD group with and without antidementia medication use, and 122,399 matched pairs were yielded. The incidence of hip fractures (4.0% vs. 1.9%, p < 0.001) and all clinical fractures (10.5% vs. 9.0%, p < 0.001) significantly decreased and that of radial fractures increased (0.6% vs. 1.0%, p < 0.001) in AD patients with antidementia medication use compared with AD patients without antidementia medication use. No significant difference was found in vertebral fractures (6.6% vs. 6.5%, p = 0.51). Overall, these results suggest a positive relationship between antidementia medication use and fracture prevention in patients with AD.

Prescription of vitamin D was associated with a lower incidence of hip fractures.

Patients with osteoporosis are prone to fragility fractures. Evidence of the effects of active forms of vitamin D on hip fracture prevention is insufficient. We examined the association between vitamin D prescription and incidence of new fractures using the data of osteoporotic patients from the nationwide health insurance claims database of Japan. The follow-up period was 3 years after entry. The untreated patients were never prescribed vitamin D during follow-up (n = 422,454), and the treated patients had a vitamin D medication possession ratio of ≥ 0.5 at all time points (n = 169,774). Propensity score matching was implemented on these groups, yielding 105,041 pairs, and subsequently, the control and treatment groups were established and analyzed. The incidence of new fractures was significantly lower in the treatment group compared with the control group (6.25% vs. 5.69%, hazard ratio 0.936 [95% confidence interval 0.904-0.970], p < 0.001*). By site, hip fractures significantly decreased (0.89% vs. 0.42%, p < 0.001), but not vertebral and radial fractures. Subgroup analysis by vitamin D type showed a significantly lower incidence of total fractures only in alfacalcidol (hazard ratio 0.676 [95% confidence interval 0.628-0.728], p < 0.001*). The results suggest that vitamin D prescription was associated with a reduced incidence of hip fractures.

Association between the type of hypnotic drug and in-hospital fractures in older patients with neurocognitive disorders: A case-control study using a nationwide database.

AIM: Hypnotics might increase the risk of falls and fractures in older patients with neurocognitive disorders. Orexin receptor antagonists have recently been approved, but the relationship between the new drugs and fractures remains unclarified. This study aimed to evaluate the association between the type of hypnotic and in-hospital fractures in older patients with neurocognitive disorders using a nationwide inpatient database. METHODS: Using the Japanese Diagnosis Procedure Combination database, we collected information on inpatients aged ≥65 years with neurocognitive disorders between April 2014 and March 2021. We examined trends in the prescription patterns of benzodiazepine drugs, Z-drugs, orexin receptor antagonists and melatonin receptor agonists. We also carried out a 1:4 matched case-control analysis of in-hospital fractures. The odds ratio of each hypnotic drug was estimated using a generalized estimating equation with adjustment for walking ability, comorbidities, osteoporosis, dialysis, selective serotonin reuptake inhibitor use and anti-dementia drug use. RESULTS: The prescription of benzodiazepine hypnotics decreased and that of orexin receptor antagonists increased. This case-control analysis included 6832 patients with fractures and 23 463 controls. Ultrashort-acting benzodiazepines, short-acting benzodiazepines and Z-drugs were associated with an increased risk of bone fracture (odds ratio [95% confidence interval] 1.38 [1.08-1.77], 1.38 [1.27-1.50], 1.49 [1.37-1.61], respectively). Orexin receptor antagonists were not associated with an increased risk of bone fracture (1.07 [0.95-1.19]). CONCLUSIONS: In contrast to other types of hypnotics, orexin receptor antagonists were not associated with in-hospital fractures in older patients with neurocognitive disorders. Geriatr Gerontol Int 2023; 23: 500-505.

Kampo formula hochu-ekki-to (Bu-Zhong-Yi-Qi-Tang, TJ-41) ameliorates muscle atrophy by modulating atrogenes and AMPK in vivo and in vitro.

BACKGROUND: Muscle disuse results in loss of skeletal muscle mass and function. Hochu-ekki-to (TJ-41; Bu-Zhong-Yi-Qi-Tang in Chinese) is an herbal medicinal formulation used to treat patients with frailty, fatigue and appetite loss. It has been suggested that two atrogenes, atrogin-1 and muscle Ring finger 1 (MuRF1), are ubiquitin ligases involved in disuse-induced muscle atrophy and that 5' adenosine monophosphate-activated protein kinase (AMPK) is involved in skeletal muscle metabolism. Effects of TJ-41 on disuse-induced muscle atrophy are unclear. METHODS: We subjected differentiated C2C12 myotubes to serum starvation, then examined the effects of TJ-41 on atrogenes expression, AMPK activity and the morphology of the myotubes. Male C57BL/6J mice were subjected to tail-suspension to induce hindlimb atrophy. We administered TJ-41 by gavage to the control group and the tail-suspended group, then examined the effects of TJ-41 on atrogene expression, AMPK activity, and the muscle weight. RESULTS: Serum starvation induced the expression of atrogin-1 and MuRF1 in C2C12 myotubes, and TJ-41 significantly downregulated the expression of atrogin-1. Tail-suspension of the mice induced the expression of atrogin-1 and MuRF1 in skeletal muscle as well as its muscle atrophy, whereas TJ-41 treatment significantly downregulated the expression of atrogin-1 and ameliorated the loss of the muscle weight. In addition, TJ-41 also activated AMPK and inactivated Akt and mTOR in skeletal muscle in vivo. CONCLUSION: TJ-41 inhibited atrogenes in an Akt-independent manner as well as activating AMPK in skeletal muscles in vivo, further implying the therapeutic potential of TJ-41 against disuse-induced muscle atrophy and other atrogenes-dependent atrophic conditions.

Effectiveness of the Questionnaire for Medical Checkup of Old-Old (QMCOO) to diagnose frailty in community-dwelling older adults.

AIM: Although frailty could be reversible by early diagnosis and interventions, it lacks definite diagnostic criteria. The Kihon Checklist is a 25-item questionnaire that diagnoses frailty with a cutoff score of 7/8. The Questionnaire for Medical Checkup of Old-Old (QMCOO) was recently established and used for medical checkups among Japanese older adults, but no method or cutoff score for diagnosing frailty has been established. Thus, we aimed to diagnose frailty using the QMCOO and to determine its cutoff score by comparing it with that of the Kihon Checklist. METHODS: We recruited 223 older adults in Yasugi City and Yonago City to answer all the questions in the Kihon Checklist and the QMCOO at the same time. Those scoring ≥8 for the Kihon Checklist (n = 38) were diagnosed as frail. We also determined the cutoff score for frailty for the QMCOO and examined which questionnaire items affected the frailty status. RESULTS: The QMCOO and the Kihon Checklist score showed a significant positive correlation (r = 0.670, P < 0.001). The area under the curve was 0.851. A cutoff score of 3/4 for the QMCOO represented the best results (sensitivity, 76.3%; specificity, 88.1%; and accuracy, 86.1%). Multiple linear regression analysis revealed that subjective health status, body weight loss, slowness, and forgetfulness still affected the frailty status. CONCLUSIONS: A cutoff score of 3/4 for the QMCOO might be effective in diagnosing frailty. Geriatr Gerontol Int 2022; 22: 127-131.

Association between comprehensive geriatric assessment and polypharmacy at discharge in patients with ischaemic stroke: A nationwide, retrospective, cohort study.

Background: Polypharmacy and its adverse drug events are a major healthcare challenge related to falls, hospitalisations and mortality. Comprehensive geriatric assessment (CGA) may contribute to polypharmacy improvement, however, there is no clear evidence so far. Methods: Using a national inpatient database in Japan from April 1, 2014 to March 31, 2018, we investigated the association between CGA and polypharmacy. We identified patients aged ≥65 years admitted for ischaemic stroke who could receive oral medications. Propensity score matching was conducted for patients with and without CGA during hospitalisation. The outcomes were polypharmacy (defined as use of five or more types of oral medications) at discharge, the number of medication types prescribed at discharge, and the difference between the numbers of medication types prescribed on admission and at discharge. Findings: A total of 162,443 patients were analysed, of whom 39,356 (24·2%) received CGA, and propensity score matching identified 39,349 pairs. Compared with non-CGA group, the CGA group had a significantly lower proportion of polypharmacy at discharge (34·3% vs. 32·9%, p < 0·001) and a smaller number of medication types prescribed at discharge (3·84 vs. 3·76, p < 0·001). Interpretation: This study shows the clear evidence that there is a positive relationship between CGA and a reduction in the number of medications in older inpatients with ischaemic stroke. Funding: The Ministry of Health, Labour and Welfare, Japan and the Ministry of Education, Culture, Sports, Science and Technology, Japan.

Association between protein intake and mortality in older patients receiving parenteral nutrition: a retrospective observational study.

BACKGROUND: Malnutrition of inpatients is often overlooked and remains a serious concern. However, there are few studies on the relations between infused energy and amino acid intakes and clinical outcomes in older patients on parenteral nutrition. OBJECTIVES: We aimed to determine the short-term outcomes of infused energy and amino acid intakes in older patients receiving parenteral nutrition. METHODS: We conducted a retrospective observational study using a national inpatient database covering >1000 hospitals in Japan. Participants were those who underwent central venous (CV) port insertion between 2011 and 2016, were aged ≥65 y, and did not have cancer. Based on the types and amounts of products used for enteral feeding and intravenous feeding on postoperative day (POD) 7 after CV port insertion, the infused energy and amino acid intakes were estimated. The primary end point was mortality on POD 90. Multivariable logistic regression was performed to investigate the relations of infused energy and amino acid intakes with mortality on POD 90. RESULTS: A total of 10,153 patients aged ≥65 y who underwent CV port insertion were included. The mortality rates at 90 d after central venous port insertion were 14.9% and 14.0% (risk difference, 0.9%; 95% CI: -0.5%, 2.3%; P = 0.216) with infused energy intakes <20 and ≥20 kcal/kg, respectively, and 15.4% and 13.2% (risk difference, 2.2%; 95% CI: 0.9%, 3.6%; P = 0.001) with infused amino acid intakes <0.8 and ≥0.8 g/kg, respectively. The differences were retained after adjustment for multiple variables including hospital, age, sex, BMI, emergency admission, and 27 major underlying diseases. The OR for the ≥0.8-g/kg group compared with the <0.8-g/kg group was 0.87 (95% CI: 0.77, 0.99; P = 0.028). CONCLUSIONS: A positive relation between infused amino acid intake and mortality was found in older patients receiving parenteral nutrition.

Association between comprehensive geriatric assessment and short-term outcomes among older adult patients with stroke: A nationwide retrospective cohort study using propensity score and instrumental variable methods.

BACKGROUND: Comprehensive geriatric assessment (CGA) is a multidimensional and multidisciplinary method to identify geriatric conditions among older patients. The aim of the present study was to examine the associations between CGA and short-term outcomes among older adult inpatients with stroke. METHODS: The study was a nationwide, retrospective cohort study. We used the Diagnosis Procedure Combination database, a national Japanese inpatient database, to identify older adult stroke patients from 2014 to 2017. The associations between CGA and in-hospital mortality, length of hospital stay, readmission rate, rehabilitation intervention, and introduction of home health care were evaluated using propensity score matching and instrumental variable analysis. FINDINGS: We identified 338,720 patients, 21·3% of whom received CGA. A propensity score-matched analysis of 53,861 pairs showed that in-hospital mortality was significantly lower in the CGA group than in the non-CGA group (3·6% vs. 4·1%, p < 0·001). The rate of long-term hospitalization (> 60 days) was significantly lower in the CGA group than in the non-CGA group (8·7% vs. 10·1%, p < 0·001), and the rates of rehabilitation intervention (30·3% vs. 24·9%, p < 0·001) and home health care (8·3% vs. 7·6%, p = 0·001) were both higher in the CGA group than in the non-CGA group. Instrumental variable analysis showed similar results. INTERPRETATION: CGA was significantly associated with the examined short-term outcomes. These findings from Japan, one of the most aged countries worldwide, highlight the possible benefits of CGA for short-term outcomes and can be of use for health policy in other international contexts. FUNDING: This work was supported by grants from the Ministry of Health, Labour and Welfare, Japan (19AA2007 and H30-Policy-Designated-004) and the Ministry of Education, Culture, Sports, Science and Technology, Japan (17H04141).

Malnutrition-Related Health Care Cost in Japan: An Analysis of Health Insurance Claims Data.

The objective of our study is to evaluate the prevalence and health care cost of malnutrition in Japan. Using the health insurance data, we defined 2 types of malnutrition, strictly diagnosed malnutrition (SDM) and disease-associated malnutrition (DAM) by International Classification of Diseases 10th Revision. We also analyzed the health care costs by body mass index (BMI) data from medical checkups. The nationwide prevalence of SDM was estimated 0.8%, and that of SDM plus DAM was 2.9%. The total annual health care cost for SDM patients in Japan was $14.5 billion, representing 4.3% of the national health expenditures in 2014; the excess cost for patients with SDM was estimated to be $9.7 billion. The health care costs became high among the patients with either low BMI or high BMI. Because of the rapidly aging population, actions are urgently needed to avoid increasing the current high health care costs of malnutrition.