Construction and evaluation of a neurofeedback system using finger tapping and near-infrared spectroscopy.

Introduction: Neurofeedback using near-infrared spectroscopy (NIRS) has been used in patients with stroke and other patients, but few studies have included older people or patients with cognitive impairment. Methods: We constructed a NIRS-based neurofeedback system and used finger tapping to investigate whether neurofeedback can be implemented in older adults while finger tapping and whether brain activity improves in older adults and healthy participants. Our simple neurofeedback system was constructed using a portable wearable optical topography (WOT-HS) device. Brain activity was evaluated in 10 older and 31 healthy young individuals by measuring oxygenated hemoglobin concentration during finger tapping and neurofeedback implementation. Results: During neurofeedback, the concentration of oxygenated hemoglobin increased in the prefrontal regions in both the young and older participants. Discussion: The results of this study demonstrate the usefulness of neurofeedback using simple NIRS devices for older adults and its potential to mitigate cognitive decline.

Contrast dependence of scattering profiles for poly(ethylene glycol) in water: Investigation by small-angle neutron scattering with 3He spin filter and small-angle x-ray scattering.

The small-angle neutron scattering (SANS) and small-angle x-ray scattering (SAXS) measurements were performed for deuterated and non-deuterated poly(ethylene glycol) (d-PEG and h-PEG, respectively) in D2O and a D2O/H2O mixed solvent (Mix) to compare the scattering profiles. To determine the coherent scattering intensity of SANS, a 3He spin filter was utilized. The scattering profiles determined by the SANS measurements were analyzed in terms of the wormlike chain model with touched beads along the contour of the chain. However, the SAXS profiles were not explained by the same model with uniform beads but with beads each consisting of a core and a shell having different electron densities. To explore the chain thickness determined from the SANS profile, the scattering intensities for different combinations of d-PEG/D2O, d-PEG/Mix, h-PEG/D2O, and h-PEG/Mix were also examined.

Financial incentives and health provider behaviour: Evidence from a capitation policy in Ghana.

The capitation payment model has been used as a supply-side cost-containment tool in controlling physician behaviour. However, little is known regarding its effectiveness in controlling costs and discouraging use of low-value care. This study seeks to examine whether financial incentives in capitation influence provider behaviour, and if so, whether such behaviour compromises outcomes for inpatients with hypertension. To this end, we evaluate the effect on outpatient visits and inpatient outcomes of the introduction of capitation into a mixed payment system involving diagnosis-related groups and fee-for-service in the Ashanti region of Ghana. We use difference-in-differences with fixed effects and event study analysis of claims data over 48 months (2016-2019). We found that providers responded to financial incentives in capitation; outpatient visits were approximately 35% lower. However, we found no significant impact of capitation on inpatient outcomes; that is, the in-hospital death rate did not increase, and the length of hospital stay (which may be a rough indicator of the severity of illness) also did not increase. These findings indicate that patient health outcomes did not deteriorate. Evidence suggests that the observed reduction in outpatient visits may be in unnecessary or low-value visits, especially at lower levels of the healthcare system.

The relaxation effect of autonomous sensory meridian response depends on personal preference.

Background: Autonomous sensory meridian response (ASMR) is a sensory response such as tingling and pleasantness from audiovisual stimuli. ASMR videos come in a wide variety of types, and personal preferences are biased. There are many reports of the effects os ASMR on sleep onset, anxiety relief, and other relaxation effects. However, prior task-oriented studies have used ASMR videos provided by the experimenter. We hypothesized that ASMR movies of a personal preference would show significantly increased activity in the nucleus accumbens, frontal cortex, and insular cortex, which are brain areas associated with relaxation. Therefore, the purpose of this study was to elucidate the neuroscientific basis for the relaxation effects of ASMR videos that match someone's personal preferences. Methods: This study included 30 healthy individuals aged ≥18 years. ASMR enthusiasts were included as the target population due to the need to have a clear preference for ASMR videos. A control video (1 type) and ASMR videos (20 types) were used as the stimulus tasks. Among the ASMR videos, those with high and low evaluation scores were considered liked and dislikedASMR videos, respectively. Functional magnetic resonance imaging was performed while the participants viewed a block design with a resting task in between. The data were analyzed using Statistical Parametric Mapping 12 to identify the areas activated by control, disliked, and liked ASMR videos. Results: Emotion-related areas (the amygdala, frontal cortex, and insular cortex) not activated by control and unliked ASMR videos were activated only by liked ASMR videos. Conclusion: The amygdala, frontal cortex, and insular cortex may be involved in the limbic dopamine circuits of the amygdala and middle frontal gyrus and the autonomic balance of the left and right insular cortices. This suggests the potential of positive mood and its use as a treatment for patients with anxiety and depression. These results suggest that the use of ASMR videos to match individual preferences may induce relaxation and have beneficial effects on depression and other disorders, and also support the introduction of ASMR videos in mental health care.

The liver-to-spleen ratio is a risk factor predicting oxygen demand in COVID-19 patients.

Background: We aimed to investigate risk factors predicting oxygen demand in COVID-19 patients. Methods: Patients admitted to Shizuoka General Hospital with COVID-19 from August 2020 to August 2021 were included. First, we divided patients into groups with and without oxygen demand. Then, we compared patients' clinical characteristics and laboratory and radiological findings to determine factors predicting oxygen demand. Results: One hundred seventy patients with COVID-19 (aged 58±15 years, 57 females) were enrolled. Common comorbidities were cardiovascular diseases (47.6%), diabetes mellitus (28.8%), and dyslipidemia (26.5%). Elder age, higher body mass index, cardiovascular diseases, diabetes mellitus, lower lymphocyte count, albumin, hepatic attenuation value, and the liver-to-spleen ratio (L/S), higher D-dimer, aspartate aminotransferase, lactate dehydrogenase, troponin-T, C-reactive protein, KL-6, chest and abdominal circumference, and visceral fat were found in patients with oxygen demand. According to the multivariate logistic regression analysis, L/S, lymphocyte count, D-dimer, and abdominal circumference under the diaphragm were independent risk factors predicting oxygen demand in COVID-19 patients. Conclusions: On admission, L/S, lymphocyte count, D-dimer, and abdominal circumference were predictive factors for oxygen demand. These factors may help in the appropriate triage of COVID-19 patients in the decision to admit them to the hospital.

Comparison of Cerebral Blood Volume during Cold and Warm Stimulation in Elderly and Young Subjects.

Background: Dementia involves a neuronal loss in the primary somatosensory cortex of the parietal lobe, causing dementia patients to perceive pain stimuli hardly. The function of temperature sensation declines. Studies measuring brain blood volume using near-infrared light have reported that patients suffering from dementia have less activation than healthy elderly people. However, the majority of these studies used tests related to cognitive function and the frontal lobe, and few have examined thermal sensation. Objective: The present study aimed to investigate the effect of cold and warm stimulation on cerebral blood volume in elderly and young subjects. Material and Methods: This observational study measured changes in oxygenated hemoglobin concentrations in the frontal cortex during cold and warm stimulation in elderly and young subjects using a near-infrared light device. The mean and standard deviation of the change in oxygenated hemoglobin concentration before and after cold and warm stimulation, as well as the center-of-gravity values, were compared between the young and the elderly. Results: During warm stimulation, the younger subjects showed an increase in blood oxygenated hemoglobin levels; however, the difference was not significant. For the elderly, no change was observed during the task. The center of gravity values was lower in the young compared to the elderly which was similar to the reaction threshold. No significant changes were observed during cold stimulation. Conclusion: Thermal sensation thresholds were impaired in the elderly compared to the young; however, cerebral blood volume changes were unclear.

Oscillometry helps assess treatment responsiveness in adults with asthma exacerbations.

BACKGROUND: It is necessary to evaluate the severity of asthma exacerbations for subjective symptoms and objective indicators. When patients cannot perform spirometry, oscillometry is a surrogate test. OBJECTIVE: We assessed the usefulness of oscillometry for the evaluation of treatment responsiveness in patients with asthma exacerbations. METHODS: The subjects included 21 consecutive patients with asthma exacerbations. Symptomatic responses, oscillometry, and spirometry (if possible) were assessed before and after treatment with corticosteroids and aminophylline. RESULTS: After treatment, all of the patients were allowed to return home and had no hospital visits. Oscillometry was feasible in all patients; however, spirometry could not be performed in 9 patients. Overall, there was a significant improvement in wheezing scores and oscillometric parameters, but not in FEV1 after treatment. The thresholds for a positive bronchodilator response in oscillometry were observed in 4 or more patients, while the minimal clinically important differences in FEV1 were observed in one patient. CONCLUSION: Oscillometry can detect improvements that cannot.

Brain function effects of autonomous sensory meridian response (ASMR) video viewing.

Background: Autonomous sensory meridian response (ASMR) is the sensation of tingling from audiovisual stimuli that leads to positive emotions. ASMR is used among young people to relax, induce sleep, reduce stress, and alleviate anxiety. However, even without experiencing tingling, ASMR is used by many young people to seek relaxation. Auditory stimulation in ASMR is thought to play the most important role among its triggers, and previous studies have used a mixture of auditory and visual stimulation and auditory stimulation. This is the first study to approach the differences between the effects of direct audiovisual and auditory stimulation from the perspective of brain function using functional magnetic resonance imaging (fMRI) and to clarify the effects of ASMR, which attracts many young people. Methods: The subjects were 30 healthy subjects over 19 years old or older who had not experienced tingling. Brain function was imaged by fMRI while watching ASMR videos or listening to the sound files only. We administered a questionnaire based on a Likert scale to determine if the participants felt a "relaxed mood" and "tingling mood" during the task. Results: Significant activation was found in the visual cortex for audiovisual stimulation and in the visual and auditory cortex for auditory stimulation. In addition, activation of characteristic sites was observed. The specific sites of activation for audiovisual stimulation were the middle frontal gyrus and the left nucleus accumbens, while the specific sites of activation for auditory stimulation were the bilateral insular cortices. The questionnaire showed no significant differences in either "relaxed mood" or "tingling mood" in response to auditory and visual stimulation or auditory stimulation alone. Conclusion: The results of this study showed that there was a clear difference between auditory and audiovisual stimulation in terms of the areas of activation in the brain, but the questionnaire did not reveal any difference in the subjects' mood. Audiovisual stimulation showed activation of the middle frontal gyrus and the nucleus accumbens, whereas auditory stimulation showed activation of the insular cortex. This difference in brain activation sites suggests a difference in mental health effects between auditory and audiovisual stimulation. However, future research on comparisons between those who experience tingling and those who do not, as well as investigations of physiological indices, and examination of the relationship with activated areas in the brain may show that ASMR is useful for mental health.

Prefrontal Cerebral Oxygenated Hemoglobin Concentration during the Category Fluency and Finger-Tapping Tasks in Adults with and without Mild Cognitive Impairment: A Near-Infrared Spectroscopy Study.

Mild cognitive impairment (MCI) is considered to be the limit between the cognitive changes of aging and early dementia; thus, discriminating between participants with and without MCI is important. In the present study, we aimed to examine the differences in the cerebral oxyhemoglobin signal between individuals with and without MCI. The cerebral oxyhemoglobin signal was measured when the participants (young and elderly controls as well as patients with MCI) performed category fluency, finger tapping, and dual tasks using head-mounted near-infrared spectroscopy; the results were compared between the groups. The cerebral oxyhemoglobin signal trended toward the highest values during the category fluency task in young participants and during the finger-tapping task in elderly participants regardless of the MCI status. The area under the curve was approximately 0.5, indicating a low discrimination ability between elderly participants with and without MCI. The measurement of the blood flow in the prefrontal cortex may not accurately quantify cognitive and motor performance to detect MCI. Finger tapping may increase cerebral blood flow in individuals with and without MCI during the task.

Physical Load While Using a Tablet at Different Tilt Angles during Sitting and Standing.

Few standards and guidelines to prevent health problems have been associated with tablet use. We estimated the effects of posture and tablet tilt angle on muscle activity and posture in healthy young adults. Seventeen healthy young adults (age: 20.5 ± 3 years) performed a cognitive task using a tablet in two posture (sitting and standing) and tablet tilt angle (0 degrees and 45 deg) conditions. Segment and joint kinematics were evaluated using 16 inertial measurement unit sensors. Neck, trunk, and upper limb electromyography (EMG) activities were monitored using 12 EMG sensors. Perceived discomfort, kinematics, and EMG activities were compared between conditions using the Friedman test. The perceived discomfort in the standing-0 deg condition was significantly higher than in the remaining three conditions. Standing posture and tablet inclination significantly reduced the sagittal segment and joint angles of the spine, compared with sitting and flat tablet conditions. Similarly, standing posture and tablet inclination significantly reduced EMG activities of the dorsal neck, upper, and lower trunk muscles, while increasing EMG activity of shoulder flexors. Standing posture and tablet inclination reduced the sagittal flexion angle, and dorsal neck, upper, and lower trunk muscle activities, while potentially increasing the muscle activity of arm flexors.

Competition and quality of care under regulated fees: evidence from Ghana.

BACKGROUND: How competition affects the quality of care is still not well understood empirically because of limited and mixed results. This study examined whether competition leads to higher or lower quality health outcomes in Ghana. METHODS: We used administrative claims data of hypertension patients for 2017 - 2019 (36 months), and an instrumental variable method to examine the effect of competition, measured as an increase in district doctor-to-population ratio on hospital-level ambulatory care sensitive condition hospitalization and in-hospital death rates. RESULTS: Overall, we found that an increase in doctor density improves the quality of care for hypertension patients in Ghana. That is, when there are more doctors, fewer patients are hospitalized, and the risk of in-hospital deaths decreases. This result is robust to analyses at the individual and district population levels for ambulatory care sensitive hospitalizations rate. CONCLUSIONS: Our findings suggest that in the presence of physician-induced demand, competition can lead to improvement in the quality of care, possibly through improved access to healthcare and increased physician time and contact per patient. Future health policies need to consider possible welfare benefits of induced medical services and training more doctors.

Integration of bioassay and non-target metabolite analysis of tomato reveals that ß-carotene and lycopene activate the adiponectin signaling pathway, including AMPK phosphorylation.

Adiponectin, an adipokine, regulates glucose metabolism and insulin sensitivity through the adiponectin receptor (AdipoR). In this study, we searched for metabolites that activate the adiponectin signaling pathway from tomato (Solanum lycopersicu). Metabolites of mature tomato were separated into 55 fractions by liquid chromatography, and then each fraction was examined using the phosphorylation assay of AMP-protein kinase (AMPK) in C2C12 myotubes and in AdipoR-knockdown cells by small interfering RNA (siRNA). Several fractions showed AMPK phosphorylation in C2C12 myotubes and siRNA-mediated abrogation of the effect. Non-targeted metabolite analysis revealed the presence of 721 diverse metabolites in tomato. By integrating the activity of fractions on AMPK phosphorylation and the 721 metabolites based on their retention times of liquid chromatography, we performed a comprehensive screen for metabolites that possess adiponectin-like activity. As the screening suggested that the active fractions contained four carotenoids, we further analyzed ß-carotene and lycopene, the major carotenoids of food. They induced AMPK phosphorylation via the AdipoR, Ca2+/calmodulin-dependent protein kinase kinase and Ca2+ influx, in addition to activating glucose uptake via AdipoR in C2C12 myotubes. All these events were characteristic adiponectin actions. These results indicated that the food-derived carotenoids, ß-carotene and lycopene, activate the adiponectin signaling pathway, including AMPK phosphorylation.

Stress Evaluation by Hemoglobin Concentration Change Using Mobile NIRS.

Previous studies have reported a relationship between stress and brain activity, and stress has been quantitatively evaluated using near-infrared spectroscopy (NIRS). In the present study, we examined whether a relationship exists between salivary amylase levels and brain activity during the trail-making test (TMT) using mobile NIRS. This study aimed to assess stress levels by using mobile NIRS. Salivary amylase was measured with a salivary amylase monitor, and hemoglobin concentration was measured using Neu's HOT-2000. Measurements were taken four times for each subject, and the values at each measurement were evaluated. Changes in the values at the first-second, second-third, and third-fourth measurements were also analyzed. Results showed that the value of the fluctuations has a higher correlation than the comparison of point values. These results suggest that the accuracy of stress assessment by NIRS can be improved by using variability and time-series data compared with stress assessment using NIRS at a single time point.

Mucus Plugs and Small Airway Dysfunction in Asthma, COPD, and Asthma-COPD Overlap.

PURPOSE: There are reports concerning mucus plugs detected on high-resolution computed tomography images and airflow obstruction in asthma and chronic obstructive pulmonary disease (COPD). However, little is known about the associations between mucus plugs and small airway dysfunction (SAD). We evaluated the relationship between mucus plugs and pulmonary function in patients with asthma, COPD, and asthma-COPD overlap (ACO), and investigated the relevance to SAD and type 2 inflammation in a retrospective study. METHODS: Subjects included 49 asthmatic, 40 ACO, and 41 COPD patients. ACO was diagnosed based on the Japanese Respiratory Society ACO guidelines. Clinical and laboratory parameters, including blood eosinophil count, serum total IgE levels, fractional exhaled nitric oxide (FeNO), spirometry, and forced oscillation technique (FOT), were compared between patients with and without mucus plugs. RESULTS: Mucus plugs were found in 29 (59%) asthmatic, 25 (65%) ACO, 17 (41%) COPD patients. Patients with mucus plugs had reduced spirometry and larger FOT parameters, especially in COPD patients. Mucus scores correlated positively with IgE in ACO and FeNO in asthmatic patients, but not in COPD patients. Multivariate logistic regression analysis revealed that SAD parameters, including forced vital capacity and resonant frequency, a respiratory reactance parameter, were significantly associated with the presence of mucus plugs in the whole studied population. CONCLUSIONS: SAD, rather than large airway dysfunction, was associated with mucus plugs in asthma, ACO, and COPD patients.

Forced oscillatory parameters as predictors of COPD assessment test improvement in untreated COPD patients.

BACKGROUND: Few studies have examined whether baseline spirometry and the forced oscillation technique (FOT) would predict The COPD Assessment Test (CAT) score improvement after treatment of untreated COPD patients. METHODS: The study subjects included 65 untreated COPD patients. They underwent the CAT, spirometry, and FOT (MostGraph) before and after treatment for more than 2 months. In addition, recursive partitioning analysis was performed using spirometry and the FOT parameters to identify the predictors of CAT improvement (CAT score ≥2). RESULTS: CAT scores and lung function significantly improved after treatment. Recursive partitioning analysis identified 3 improved classes, defined by Rrs at 20 Hz (R20), Xrs at 5 Hz (X5), and ΔX5, but not by spirometry. The accuracy of predicting CAT improvement was as follows: odds ratio, 25.3; 95 % confidence interval, 6.1 to 104.1; sensitivity, 91.2 %; specificity, 71.0 %; positive likelihood ratio, 3.14; and negative likelihood ratio, 0.12. CONCLUSIONS: FOT helps predict improved health status in untreated COPD patients.

Blood eosinophil count and FeNO to predict benralizumab effectiveness in real-life severe asthma patients.

OBJECTIVE: Benralizumab is a promising drug for severe uncontrolled asthma. This study aimed to clarify the effectiveness of benralizumab in a real-life setting. METHODS: Subjects included 24 patients with severe type 2 asthma who received benralizumab between April 2018 and July 2019. Changes in parameters, exacerbation frequency, and oral corticosteroid (OCS) use after 4 and 24 weeks of administration were examined. The parameters included the Global Evaluation of Treatment Effectiveness (GETE) scale, Asthma Control Questionnaire (ACQ), Asthma Control Test (ACT), blood eosinophils, fractional exhaled nitric oxide (FeNO), and spirometry. The response to treatment was defined as follows: for patients with exacerbations or OCS use before treatment initiation, a reduction of ≥50% in exacerbation frequency or OCS use; and for patients without exacerbations or OCS use, an improvement of ≥0.5 in ACQ scores and ≥3 in ACT scores, or of ≥10.38% in FEV1. RESULTS: Twenty-one patients completed the treatment for 24 weeks. Excellent and good GETE scales and ACQ and ACT improvement were found in 67% of the patients at 4 weeks, and the effect continued until 24 weeks. The patients' rate with exacerbations was significantly reduced compared to the previous 24 weeks before administration. In 17 patients receiving OCS, the use could be reduced or quit in 14 patients. Overall, 16 patients (76.2%) met the responder definition and could be predicted by the baseline eosinophil count and FeNO levels with the best cutoff values of 100/µL and 40 ppb, respectively. CONCLUSIONS: Blood eosinophil and FeNO could predict benralizumab effectiveness.

Competition and physician-induced demand in a healthcare market with regulated price: evidence from Ghana.

Using panel data of administrative claims spanning 36 months (2017-2019) and an instrumental variable method, this study examines whether physician-induced demand for hypertension disease care exists in Ghana's healthcare system where price is regulated, and there is no co-payment. We find that an increase in competition-measured as a high doctor-to-population ratio at the district level-leads to an increase in the number of physician visits, suggesting physician-induced demand exists, and that effects are greater for large hospitals and public health providers. This result is further supported by alternative measures and specifications showing that physicians' revenue from medication and gross revenue increase as the physician density increases. These pattern suggest that physicians in high density areas, faced with a decrease in number of patients per physician, make up for the decline in income by inducing more patient visits.

Effects of broccoli sprout supplements enriched in glucoraphanin on liver functions in healthy middle-aged adults with high-normal serum hepatic biomarkers: A randomized controlled trial.

Sulforaphane (SFN), an isothiocyanate derived from glucoraphanin, has antioxidant, and anti-inflammatory effects that may be beneficial for improving liver function. However, few studies regarding the effects of glucoraphanin on the biological markers related to liver function, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase (γ-GTP) in healthy individuals have been reported. This randomized, double-blind, placebo-controlled parallel- group trial was conducted from April 22 to December 25, 2021 and compared the effects of broccoli sprout supplements enriched in glucoraphanin (glucoraphanin supplements) (n = 35) with those of placebo supplements (n = 35). This trial was registered with the University Hospital Medical Information Network Clinical Trial Registry (UMIN-CTR; ID number UMIN000044005) https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view. cgi?recptno=R000050252. Glucoraphanin significantly improved serum ALT levels at 24 weeks compared to placebo supplements. However, no significant difference in serum glutathione levels, one of the major antioxidants synthesized in the liver, was observed between the two groups. In conclusion, daily intake of the glucoraphanin supplements is beneficial for maintaining liver health in healthy, middle-aged adults with high-normal serum hepatic biomarkers, although further studies focusing on other antioxidant markers are needed to understand how glucoraphanin improves liver function.

TOMATOMET: A metabolome database consists of 7118 accurate mass values detected in mature fruits of 25 tomato cultivars.

The total number of low-molecular-weight compounds in the plant kingdom, most of which are secondary metabolites, is hypothesized to be over one million, although only a limited number of plant compounds have been characterized. Untargeted analysis, especially using mass spectrometry (MS), has been useful for understanding the plant metabolome; however, due to the limited availability of authentic compounds for MS-based identification, the identities of most of the ion peaks detected by MS remain unknown. Accurate mass values of peaks obtained by high accuracy mass measurement and, if available, MS/MS fragmentation patterns provide abundant annotation for each peak. Here, we carried out an untargeted analysis of compounds in the mature fruit of 25 tomato cultivars using liquid chromatography-Orbitrap MS for accurate mass measurement, followed by manual curation to construct the metabolome database TOMATOMET (http://metabolites.in/tomato-fruits/). The database contains 7,118 peaks with accurate mass values, in which 1,577 ion peaks are annotated as members of a chemical group. Remarkably, 71% of the mass values are not found in the accurate masses detected previously in Arabidopsis thaliana, Medicago truncatula or Jatropha curcas, indicating significant chemical diversity among plant species that remains to be solved. Interestingly, substantial chemical diversity exists also among tomato cultivars, indicating that chemical profiling from distinct cultivars contributes towards understanding the metabolome, even in a single organ of a species, and can prioritize some desirable metabolic targets for further applications such as breeding.

Effectiveness of a 23-valent pneumococcal polysaccharide vaccine for the prevention of pneumococcal pneumonia in the elderly with chronic respiratory diseases: a case-control study of a single center.

BACKGROUND: The effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) in preventing pneumococcal pneumonia has been controversial. METHODS: To evaluate the effectiveness of the PPSV23 in elderly outpatients with chronic respiratory diseases, we carried out a case-control study, including 4128 outpatients aged ≥ 65 years, in the respiratory department. RESULTS: There were 320 vaccinated patients, of which 164 were diagnosed with pneumococcal pneumonia. The adjusted odds ratio was 0.39 (95% confidence interval (CI), 0.17 to 0.89). In the subsets consisting of age groups ≥ 70 and ≥ 75 years, the adjusted odds ratio (95% CI) was respectively 0.16 (0.04 to 0.67) and 0.15 (0.02 to 1.12). CONCLUSION: This real-world study suggests that PPSV23 can be useful in preventing pneumococcal pneumonia in the elderly with chronic respiratory diseases.