Gastroesophageal reflux disease is a risk factor for sputum production in the general population: the Nagahama study

BACKGROUND

Chronic sputum production in the general population is historically associated with clinical indices including male sex and smoking history. However, its relationship with gastroesophageal reflux disease (GERD), which may prove an underlying factor in sputum production, is unclear. We aimed to clarify factors associated with sputum production in the general population in cross-sectional and longitudinal manners.

METHODS

In the Nagahama study, a community-based cohort study, 9804 subjects were recruited between 2008 and 2010 (baseline assessment), 8293 of whom were followed from 2013 to 2015 (follow-up assessment). This study contained a self-completed questionnaire which included medical history, assessment of sputum production, and a frequency scale for symptoms of GERD. A Frequency Scale for Symptoms of Gastroesophageal Reflux Disease score of ≥ 8 was defined as GERD. In addition to the frequency of sputum production at each assessment, frequency of persistent sputum production defined as sputum production at both assessments was examined.

RESULTS

Frequency of sputum production was 32.0% at baseline and 34.5% at follow-up. Multivariable analysis demonstrated that sputum production at baseline was significantly associated with GERD [odds ratio (OR), 1.92; 95% confidence interval (CI) 1.73-2.13] and post-nasal drip (PND) (OR, 2.40; 95% CI 2.15-2.68), independent of other known factors such as older age, male sex and smoking history. These associations between sputum production and GERD or PND were also observed at follow-up. In longitudinal analysis, 19.4% had persistent sputum production and 12.3% had transient sputum production, i.e., at baseline only. Multivariable analysis for risk of persistence of sputum production revealed that persistent sputum production was associated with GERD and PND, in addition to the known risk factors listed above. The proportion of subjects with GERD at both assessments was highest among subjects with persistent sputum production.

CONCLUSIONS

Cross-sectional and longitudinal analysis demonstrated an association in the general population between sputum production and GERD, as well as PND, independent of known risk factors. The presence of GERD should be assessed in patients complaining of sputum production.

Clinical and Genetic Characteristics of Pachydrusen in Eyes with Central Serous Chorioretinopathy and General Japanese Individuals

PURPOSE

To survey the prevalence and clinical and genetic characteristics of pachydrusen in eyes with central serous chorioretinopathy (CSC) and those of Japanese individuals in the general population.

DESIGN

Prospective, observational cohort study.

PARTICIPANTS

One thousand thirty-seven Japanese patients were included in this study. Three hundred seven patients (614 eyes) had treatment-naïve CSC without choroidal neovascularization in either eye, whereas 730 individuals (1640 eyes) were Japanese individuals from the general population without explicit ocular diseases.

METHODS

Pachydrusen were detected using color fundus photography, and subfoveal choroidal thickness was measured using OCT. Genotypic distributions of 3 single nucleotide polymorphisms, ARMS2 A69S, CFH I62V, and CFH Y402H, were evaluated.

MAIN OUTCOME MEASURES

Prevalence of pachydrusen and association with choroidal thickness.

RESULTS

The prevalence of pachydrusen was significantly higher among CSC patients than among the general population group (40.1% vs. 15.6%; P < 0.001). Individuals with pachydrusen in either group were significantly older than those without pachydrusen (CSC patients: 62.1 years vs. 48.8 years [P < 0.001]; general individuals: 70.3 years vs. 51.9 years [P < 0.001]). No significant difference was found in subfoveal choroidal thickness between those with and without pachydrusen (CSC patients: 370 μm vs. 375 μm; [P = 0.574]; general population: 297 μm vs. 303 μm [P = 0.521]). However, after adjusting for age, gender, and refractive error, subfoveal choroidal thickness was notably thicker in individuals with pachydrusen than that in individuals without pachydrusen in both groups (P = 0.003 and P = 0.013, respectively). No significant difference was found in genotype distributions between CSC patients with pachydrusen and those without it; whereas, the T allele frequency of ARMS2 A69S was higher in general population individuals with pachydrusen than that in general population individuals without pachydrusen (42.2% vs. 33.9%; P < 0.001; OR, 1.86, adjusted for age, gender, and choroidal thickness).

CONCLUSIONS

Pachydrusen was observed more frequently in CSC patients compared with individuals from the general population. In both groups, pachydrusen was associated with a thicker choroid, suggesting that pachydrusen should be considered as a significant sign of pachychoroid.

Cerebral small vessel disease genomics and its implications across the lifespan

White matter hyperintensities (WMH) are the most common brain-imaging feature of cerebral small vessel disease (SVD), hypertension being the main known risk factor. Here, we identify 27 genome-wide loci for WMH-volume in a cohort of 50,970 older individuals, accounting for modification/confounding by hypertension. Aggregated WMH risk variants were associated with altered white matter integrity (p = 2.5×10-7) in brain images from 1,738 young healthy adults, providing insight into the lifetime impact of SVD genetic risk. Mendelian randomization suggested causal association of increasing WMH-volume with stroke, Alzheimer-type dementia, and of increasing blood pressure (BP) with larger WMH-volume, notably also in persons without clinical hypertension. Transcriptome-wide colocalization analyses showed association of WMH-volume with expression of 39 genes, of which four encode known drug targets. Finally, we provide insight into BP-independent biological pathways underlying SVD and suggest potential for genetic stratification of high-risk individuals and for genetically-informed prioritization of drug targets for prevention trials.

Glycemic Control and Insulin Improve Muscle Mass and Gait Speed in Type 2 Diabetes: The MUSCLES-DM Study

OBJECTIVES

Type 2 diabetes is a risk factor for sarcopenia. Evidence on the prevention of sarcopenia using blood glucose-lowering therapy is limited. We aimed to examine the relationship between changes in glycemic control and sarcopenia and the effect of antidiabetic agents against sarcopenia in patients with type 2 diabetes.

DESIGN

We conducted an observational longitudinal study.

SETTING AND PARTICIPANTS

In total, 588 Japanese patients with diabetes of an ongoing multicenter study completed 1-year follow-up measurements for sarcopenia and clinical data.

METHODS

The data set of the Multicenter Study for Clarifying Evidence for Sarcopenia in patients with Diabetes Mellitus (the MUSCLES-DM study) was analyzed.

RESULTS

During the follow-up period, the frequency of sarcopenia marginally increased, and the means of skeletal muscle mass index (SMI), handgrip strength, and gait speed did not show any changes. However, on dividing into 5 groups depending on the degree of changes in glycated hemoglobin (HbA_1c) value, the patients with a decrease of ≥1% in HbA_1c exhibited a significant increase in SMI. Our analysis revealed similar results for gait speed but not handgrip strength. Using the multiple linear regression model, we identified that a ≥1% decrease in HbA_1c value was an independent determinant of the changes in SMI and gait speed. We also determined that insulin use at baseline was an independent factor for the changes in SMI.

CONCLUSIONS AND IMPLICATIONS

Correction of poor glycemic control and use of insulin were significantly associated with the increase in skeletal muscle mass or gait speed in Japanese patients with type 2 diabetes. The current finding increases our understanding of the importance of glycemic control for the prevention of cardiovascular diseases and sarcopenia.

Obesity with radiological changes or depression was associated with worse knee outcome in general population: a cluster analysis in the Nagahama study

Background

In knee osteoarthritis (OA), pain is the most frequent and dominant symptom. However, which factors other than radiological changes contribute to the symptoms is unresolved. The aims of this study were to identify factors affecting knee pain from various variables with radiological changes taken into count and exploratively examine what subgroups or phenotype could be identified by cluster analysis using the identified knee pain factors.

Methods

Patients 60 years or older who underwent radiographic evaluation were included in this cross-sectional study, and those subjects who completed a questionnaire about knee symptoms without missing data were eligible for analysis. Multiple regression analysis was used to examine the associations between selected variables and The Japanese Knee Osteoarthritis Measure (JKOM) pain score. We grouped the subjects by cluster analysis using identified variables.

Results

Two thousand five hundred forty-two subjects were included in the full set of analyses. Age, body mass index (BMI), radiological grade, bone mineral density (BMD), and high-sensitivity C-reactive protein (hs-CRP) showed a statistically significant correlation with radiological showing the strongest value. For dichotomous variable, presence of depression showed a statistically significant result. We used BMI, radiological grade, BMD, hs-CRP, and presence of depression as a variable for cluster analysis and identified six subgroups: (1) minimal joint disease subgroup, (2) male and high BMD subgroup, (3) high CRP subgroup, (4) severe radiological OA subgroup, (5) depressive subgroup, and (6) moderate radiological OA with high BMI subgroup, showing the worst knee outcome.

Conclusion

This study identified the factors affecting knee pain other than radiological changes and identified six subgroups of knee outcome in the general population. The results showed that obesity with radiological changes or depression was associated with worse knee outcome.

Medical history of nocturnal enuresis during school age is an independent risk factor for nocturia in adults: The Nagahama study

AIM

To evaluate the relationship between nocturia and medical history of nocturnal enuresis: two conditions where diurnal urination rhythm is disturbed.

METHODS

The Nagahama study is a longitudinal population-based health survey involving people aged 30-75 years in Nagahama city, Japan. Our analysis included 5,402 participants who completed enuresis and International Prostate Symptom Score questionnaires. Associations between nocturnal enuresis and nocturia were evaluated cross-sectionally and longitudinally with three models: (1) univariate analysis; (2) adjusted for basic characteristics (e.g., age, sex, body mass index, activity, alcohol, and smoking); and (3) adjusted for basic and clinical variables (e.g., hyperglycemia, hyperlipidemia, hypertension, renal insufficiency, insomnia, obstructive sleep apnea, and mental health).

RESULTS

In total, 1,613 participants (29.9%) had a medical history of enuresis. The mean night-time frequency was 0.73 at baseline and 0.85 at the 5-year follow-up. The cross-sectional analysis showed participants with a medical history of enuresis had night-time frequency more often than those without this history (0.84 vs. 0.68, p < .0001). Significant differences were observed in Models 2 (p < .0001) and 3 (p < .0001). The longitudinal analysis showed nocturia progression was significantly related to a history of enuresis, with odds ratios of 1.32 (p < .0001) in Model 1, 1.21 (p < .01) in Model 2, and 1.22 (p < .01) in Model 3.

CONCLUSIONS

Medical history of enuresis during school age was significantly related to nocturia in adulthood in the cross-sectional analysis, and to progression to nocturia in the longitudinal analysis. These two conditions may possess a common causative association.

Descriptive epidemiology of high frequency component based on heart rate variability from 10-second ECG data and daily physical activity among community adult residents: the Nagahama Study

Characteristics of high frequency (HF) component based on heart rate variability (HRV) in a large general population remain unclear, particularly on the relationship with daily physical activity. We aimed to characterize the distribution of HF component and examine the association with daily physical activity among community residents. We performed spectral analysis of HRV from 10-second ECG recordings among 9135 residents aged 30 to 74 years in Nagahama City, Japan. HF components were log-transformed to consider the distribution. Simple correlations between HF and age were determined. Age-adjusted mean values of HF component were calculated for each questionnaire item related to daily physical activity. Multiple regression analysis was performed to examine the effect of daily physical activity on HF component value. Mean values of logarithmically-transformed HF component (lnHF) were higher in women than in men (p < 0.001). lnHF was inversely associated with age (r = -0.40, -0.49 for men, women, respectively). Adjusted mean lnHF for physically active people was significantly higher than that in inactive people (p < 0.001). HF components from 10-second ECG recordings were moderately and negatively correlated with age in both sexes, and positively correlated with daily physical activity in the general adult population. Maintaining the level of daily physical activity, especially to exercise regularly could keep the parasympathetic function high.

Cohort Profile: The Ganka-Ekigaku Network (GEN), a Network of Japanese Ophthalmological Epidemiology Studies

PURPOSE

Japan has been known as a super-aged society, and ageing is a well-known risk factor for blinding eye diseases. However, epidemiological studies in ophthalmology are still scarce in Japan, and the sizes of the cohorts are relatively small. "Ganka-Ekigaku Network" (GEN, an acronym for the epidemiological network in ophthalmology in Japanese) is established to develop a capacity to boost each epidemiological study and enrich a potential inter-study collaboration to identify risk factors of visual impairment in aged society.

METHODS

We reviewed cohort studies in Japan with the inclusion criteria as: (1) at least n = 1000 at baseline, (2) multiple modalities of ophthalmic data, and (3) diagnosis reviewed by ophthalmologist(s), and (4) ophthalmologists are involved in the investigators group. As of January 2020, GEN includes 4 individual Japanese epidemiological studies namely, Hisayama study, Yamagata Study (Funagata), Tsuruoka Metabolomics Cohort study, and the Nagahama Prospective Genome Cohort for Comprehensive Human Bioscience.

RESULTS

GEN includes approximately 25,000 Japanese participants. The baseline surveys started from 1998 to 2012, and since then the data has been prospectively collected approximately every 5 years. A variety of ophthalmic measurements and other factors have been collected in each study in GEN: ophthalmic measurements (fundus photography, optical coherence tomography, etc.), systemic conditions (laboratory data, etc.), and others (DNA, etc.).

CONCLUSION

GEN is an open platform for observational ophthalmic epidemiological studies to share standardized methodologies. While each study in GEN pursues specific and original research questions, standardization of the methods will enable us to conduct reliable meta-analysis/pooled data analyses.

Myopia Prevalence and Ocular Biometry Features in a General Japanese Population: The Nagahama Study

PURPOSE

To describe the distribution of ocular biometry and refraction in Japanese adults.

DESIGN

Cross-sectional analysis of a prospective cohort study.

PARTICIPANTS

A total of 9850 individuals participated in the first follow-up of the Nagahama Prospective Cohort for Comprehensive Human Bioscience (the Nagahama Study) conducted between 2013 and 2016. Participants were between 34 and 80 years of age.

METHODS

All participants underwent axial length (AL; in millimeters), anterior chamber depth (ACD; in millimeters), corneal diameter (white to white; in millimeters), and central corneal thickness (CCT; in micrometers) measurement (IOL Master; Carl Zeiss Meditec, Dublin, CA) and refraction (spherical equivalent [SE]; in diopters [D]) and corneal curvature (CC; in millimeters) measurement (ARK-530A; Nidek, Aichi, Japan). Distribution of these ocular biometric parameters and prevalence of myopia, high myopia, and extreme myopia were summarized.

MAIN OUTCOME MEASURES

Distribution of ocular biometry and refraction.

RESULTS

After standardization to the national population of 2015, estimates of mean AL and SE were 24.21 mm and -1.44 D, respectively. Estimates of mean CC, corneal diameter, CCT, and ACD were 7.69 mm, 12.01 mm, 543.96 μm, and 3.21 mm, respectively. After standardization of age and gender, the prevalence of myopia (SE, ≤-0.5 D) and high myopia (SE, ≤-6.0 D) were 49.97% and 7.89%, respectively. Approximately 70% of the younger participants (34-59 years of age) showed myopia, whereas high myopia was observed in approximately 10%. Although the number of individuals with myopia or high myopia was higher in the younger age groups, the prevalence of more extreme phenotypes remained stable across all ages, especially in women. Axial length of more than 30 mm was observed only in older women (n = 5 [0.05%]).

CONCLUSIONS

We showed detailed distributions of various ocular biometry and refraction parameters using a large general Japanese cohort. Prevalences of myopia and high myopia from 2013 through 2016 were higher than those in earlier studies, which reflects recent environmental change. However, constant prevalence of extreme myopia across all ages suggests high genetic predisposition of the extreme phenotype.

Advanced Glycation End Product Accumulation Is Associated With Low Skeletal Muscle Mass, Weak Muscle Strength, and Reduced Bone Density: The Nagahama Study

BACKGROUND

The accumulation of advanced glycation end product (AGE) might exert deleterious effects on musculoskeletal properties. Our study aims to clarify this possible association in a large general population.

METHODS

This study investigated a general population of 9,203 patients (mean age, 57.8 years). Skeletal muscle mass was measured by bioelectrical impedance analysis, whereas accumulation of AGEs was assessed by skin autofluorescence (SAF-AGE). The muscle strength of upper and lower limbs and usual gait speed were measured in a portion of older (≥60 years of age) participants (n = 1,934). The speed of sound (SOS) in the calcaneal bone was assessed via a quantitative ultrasound technique.

RESULTS

In the total population, the frequency of low skeletal muscle mass linearly increased with the SAF-AGE quartiles (Q1: 14.2%, Q2: 16.1%, Q3: 21.1%, Q4: 24.8%; p < .001), and this association was independent of covariates including glycemic traits (Q4: odds ratio [OR] = 1.48, p < .001). The association between the highest SAF-AGE quartile and low skeletal muscle mass remained significant in the older subpopulation (OR = 1.85, p = .002). A similar but weak association was observed for low SOS (Q1: 8.9%, Q2: 8.3%, Q3: 10.4%, Q4: 12.2%; p < .001). Similar inverse associations were also observed with grip strength (OR = 1.98, p = .003), hip flexion strength (OR = 1.50, p = .012), and hip abduction strength (OR = 1.78, p = .001), but not with usual gait speed.

CONCLUSION

Accumulation of AGEs might be a deleterious factor for musculoskeletal properties.

Identification of type 2 diabetes loci in 433,540 East Asian individuals

Meta-analyses of genome-wide association studies (GWAS) have identified more than 240 loci that are associated with type 2 diabetes (T2D)1,2; however, most of these loci have been identified in analyses of individuals with European ancestry. Here, to examine T2D risk in East Asian individuals, we carried out a meta-analysis of GWAS data from 77,418 individuals with T2D and 356,122 healthy control individuals. In the main analysis, we identified 301 distinct association signals at 183 loci, and across T2D association models with and without consideration of body mass index and sex, we identified 61 loci that are newly implicated in predisposition to T2D. Common variants associated with T2D in both East Asian and European populations exhibited strongly correlated effect sizes. Previously undescribed associations include signals in or near GDAP1, PTF1A, SIX3, ALDH2, a microRNA cluster, and genes that affect the differentiation of muscle and adipose cells3. At another locus, expression quantitative trait loci at two overlapping T2D signals affect two genes-NKX6-3 and ANK1-in different tissues4-6. Association studies in diverse populations identify additional loci and elucidate disease-associated genes, biology, and pathways.

Sleep disordered breathing and metabolic comorbidities across sex and menopausal status in East Asians: the Nagahama Study

It is well known that the prevalence of sleep disordered breathing (SDB) is increased in patients with obesity or metabolic comorbidities. However, the way in which the prevalence of SDB increases in relation to comorbidities according to the severity of obesity remains unclear.

This cross-sectional study evaluated 7713 community participants using nocturnal oximetry ≥2 nights. SDB was assessed by the 3% oxygen desaturation index corrected for sleep duration obtained by wrist actigraphy (acti-ODI3%). SDB severity was defined by acti-ODI3%. Obesity was defined as body mass index ≥25 kg·m−2.

The prevalence of SDB was 41.0% (95% CI 39.9–42.1%), 46.9% (45.8–48.0%), 10.1% (9.5–10.8%) and 2.0% (1.7–2.3%) in normal, mild, moderate and severe SDB, respectively, with notable sex differences evident (males>post-menopausal females>premenopausal females). Comorbidities such as hypertension, diabetes and metabolic syndrome were independently associated with the prevalence of moderate-to-severe SDB, and coincidence of any one of these with obesity was associated with a higher probability of moderate-to-severe SDB (hypertension OR 8.2, 95% CI 6.6–10.2; diabetes OR 7.8, 95% CI 5.6–10.9; metabolic syndrome OR 6.7, 95% CI 5.2–8.6). Dyslipidaemia in addition to obesity was not additively associated with the prevalence of moderate-to-severe SDB. The number of antihypertensive drugs was associated with SDB (p for trend <0.001). Proportion of a high cumulative percentage of sleep time with oxygen saturation measured by pulse oximetry <90% increased, even among moderate-to-severe SDB with increases in obesity.

Metabolic comorbidities contribute to SDB regardless of the degree of obesity. We should recognise the extremely high prevalence of moderate-to-severe SDB in patients with obesity and metabolic comorbidities.

Correlates of autonomic nervous system function in a general population with special reference to HbA1c: The Nagahama study

AIMS

As the glucose tolerance of patients with diabetes worsens, autonomic nervous system (ANS) function decreases. Only a few studies, using plasma glucose, have reported on this relationship in large general populations that include people with wide range of glycemia. This study aimed to examine correlates of ANS function with special reference to HbA_1c which is more stable than plasma glucose among community residents.

METHODS

Spectral analysis was performed to assess heart rate variability (HRV) using 1-minute electrocardiogram RR interval data recordings from 7690 residents aged 35-79 years in Nagahama City, Japan. HRV parameters were log-transformed. Multiple regression analysis was performed using potential correlates.

RESULTS

lnLF decreased with age (regression coefficient, -0.025; P < 0.001), BMI (-0.010; P = 0.035), and HbA_1c (-0.068; P = 0.036). lnHF decreased with age (-0.029; P < 0.001), BMI (-0.032; P < 0.001), and HbA_1c (-0.173; P < 0.001). lnLF/HF increased with age (0.003; P = 0.002), BMI (0.023; P < 0.001), and HbA_1c (0.105; P < 0.001). Women showed lower lnLF and lnLF/HF than men. Sleep quality assessed by the Pittsburgh Sleep Quality Index, smoking and drinking had almost no relation.

CONCLUSIONS

Although the associations were weak, age, BMI and HbA_1c were inversely correlated with parasympathetic activity, while positively correlated with sympathetic activity among general residents.

Relationship of low muscle mass and obesity with physical function in community dwelling older adults: Results from the Nagahama study

AIM

Relationships of low muscle mass and obesity with physical function were investigated in older adults.

METHODS

The participants were 1922 community dwelling persons aged 60 years or older (67.7 ± 5.2 years old, 643 men and 1279 women). One-leg standing time, knee extensor muscle strength, and maximum walking speed were assessed. Muscle mass was evaluated using the bioelectrical impedance analysis (BIA) method, and skeletal mass index (SMI) was determined. For the obesity index, waist circumference with a stronger association with visceral fat was used. Participants were classified into the following four groups based on standard values of waist circumference and SMI: non-obese low-SMI, obese low-SMI, non-obese normal-SMI, and obese normal-SMI.

RESULTS

By two-way analysis of variance (obesity × SMI), the main effects of waist circumference and muscle mass were noted in the one-leg standing time. The maximum walking speed was higher in the non-obese than the obese group, and in the normal than the low SMI group. In the muscle strength, a main effect was noted only in the muscle mass of women. An interaction was noted in men and significant differences were detected between all combinations except between the non-obese low SMI and obese low SMI groups.

CONCLUSION

Low muscle mass and obesity negatively influence balance and walking abilities. However, the influence of low muscle mass and obesity on muscle strength were different between the sexes. In men, the relationship between obesity and muscle strength would be different depending on whether muscle mass is retained.

A Geometry-Based Multiple Testing Correction for Contingency Tables by Truncated Normal Distribution

Inference procedure is a critical step of experimental researches to draw scientific conclusions especially in multiple testing. The false positive rate increases unless the unadjusted marginal p-values are corrected. Therefore, a multiple testing correction is necessary to adjust the p-values based on the number of tests to control type I error. We propose a multiple testing correction of MAX-test for a contingency table, where multiple χ2-tests are applied based on a truncated normal distribution (TND) estimation method by Botev. The table and tests are defined geometrically by contour hyperplanes in the degrees of freedom (df) dimensional space. A linear algebraic method called spherization transforms the shape of the space, defined by the contour hyperplanes of the distribution of tables sharing the same marginal counts. So, the stochastic distributions of these tables are transformed into a standard multivariate normal distribution in df-dimensional space. Geometrically, the p-value is defined by a convex polytope consisted of truncating hyperplanes of test’s contour lines in df-dimensional space. The TND approach of the Botev method was used to estimate the corrected p. Finally, the features of our approach were extracted using a real GWAS data.

Creatinine to Cystatin C Ratio as a Marker of Bone Property in Older Adults: The J-SHIPP Study

OBJECTIVES

To clarify whether serum creatinine to cystatin C ratio (CCR), a marker of muscle mass and muscle function may be used as a simple marker of bone property.

DESIGN

A cross-sectional analysis.

SETTING

A general population-based observation study.

PARTICIPANTS

1,606 middle-aged to elderly (≥50 years, mean age: 66.9 ± 7.5 years old) men (n = 642) and post-menopausal women (n = 964).

MEASUREMENT

Speed of sound (SOS) at the calcaneal bone was used as a surrogate marker of bone mineral density. The cross-sectional area of the muscle at the mid-thigh was measured using computed tomography.

RESULTS

There was significant linear correlation between the quartiles of CCR and SOS (Q1: 1,495 ± 25, Q2: 1,499 ± 24, Q3: 1,507 ± 26, Q4: 1,511 ± 25 m/sec; P < 0.001) even in a sex-separated analysis. This association was independent of major covariates (Q1: β = -0.126, P < 0.001; Q2: β = -0.096, P = 0.001; Q3: β = -0.022; P = 0.412, Q4: reference) and the mid-thigh muscle mass, while creatinine alone or eGFR did not show clear association with SOS.

CONCLUSION

The CCR may be used as a simple marker of bone property independently of muscle mass in a general population with preserved renal function.

Correlation between eosinophil count, its genetic background and body mass index: The Nagahama Study

BACKGROUND

Obesity affects the pathogenesis of various chronic diseases, including asthma. Research on correlations between obesity/BMI and eosinophilic inflammation in asthma has yielded contradictory results, which could be partly ascribed to the absence of epidemiological data on the correlations. We aimed to elucidate the correlations between blood eosinophil count, its genetic backgrounds, and BMI in the general population.

METHODS

This community-based Nagahama study in Japan enrolled 9789 inhabitants. We conducted self-reporting questionnaires, lung function tests, and blood tests in the baseline and 5-year follow-up studies. A genome-wide association study (GWAS) was performed in 4650 subjects at the baseline and in 4206 of these at the follow-up to determine single-nucleotide polymorphisms for elevated blood eosinophil counts. We assessed the correlations between BMI and eosinophil counts using a multifaceted approach, including the cluster analysis.

RESULTS

Eosinophil counts positively correlated with BMI, observed upon the interchange of an explanatory variable, except for subjects with the highest quartile of eosinophils (≥200/μL), in whom BMI negatively correlated with eosinophil counts. GWAS and human leukocyte antigen (HLA) imputation identified rs4713354 variant (MDC1 on chromosome 6p21) for elevated eosinophil counts, independent of BMI and IgE. Rs4713354 was accumulated in a cluster characterized by elevated eosinophil counts (mean, 498 ± 178/μL) but normal BMI.

CONCLUSIONS

Epidemiologically, there may be a positive association between blood eosinophil counts and BMI in general, but there was a negative correlation in the population with high eosinophil counts. Factors other than BMI, particularly genetic backgrounds, may contribute to elevated eosinophil counts in such populations.

Longitudinal Analysis of Bidirectional Relationships between Nocturia and Depressive Symptoms: The Nagahama Study

PURPOSE

Although the association between nocturia and depressive symptoms has been demonstrated, the causal direction remains unclear. We investigated the directional association between nocturia and depressive symptoms using longitudinal data from the general population.

MATERIALS AND METHODS

This longitudinal analysis was conducted as part of the Nagahama Cohort Project, a population based cohort study, with baseline and 5-year followup investigations. Nocturnal voiding frequency and mental health were measured with self-report questionnaires, the International Prostate Symptom Score and the 5-item Mental Health Inventory. Logistic regression analyses and a cross-lagged panel analysis were performed to analyze the bidirectional association between nocturia and depressive symptoms.

RESULTS

With 9,764 participants at baseline, data from 8,285 were used in this analysis. Median age at baseline was 57.3 years and the proportion of men was 32.0%. New onset depressive symptoms and nocturia were observed among 369 and 793 participants, respectively. In adjusted logistic regression analyses we observed a clear dose-relationship between baseline nocturnal voiding frequency and new onset depressive symptoms (p for trend <0.001) and a weak association between baseline 5-item Mental Health Inventory and new onset nocturia (p for trend=0.0087). In a cross-lagged panel analysis the path coefficient from nocturnal voiding frequency to 5-item Mental Health Inventory (β=-0.06, p <0.001) was stronger than that from 5-item Mental Health Inventory to nocturnal voiding frequency (β=-0.02, p=0.047).

CONCLUSIONS

This longitudinal study demonstrated a bidirectional association between nocturia and depressive symptoms. The cross-lagged path coefficient suggested that nocturia could more likely be a cause than a result of depressive symptoms.