Influences of advanced age in rheumatoid arthritis: A multicentre ultrasonography cohort study.

OBJECTIVES: We aimed to evaluate the effects of age on clinical characteristics and outcomes in biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD)-naïve patients with rheumatoid arthritis (RA). METHODS: We analysed the cases of 234 Japanese b/tsDMARD-naïve RA patients who underwent b/tsDMARD treatment in a multicentre ultrasound prospective observational cohort. We compared the clinical characteristics at baseline and outcomes at 12 months between those aged ≥60 years and those <60 years. RESULTS: Compared to the <60-year-old group (n = 78), the ≥60-year-old group (n = 156) had higher inflammatory marker values and ultrasound combined scores, especially wrist joints, at baseline. Age at baseline positively correlated significantly with the ultrasound scores at baseline; however, age was not a significant variable by the multiple regression analysis. The patients treated with different MOAs in the ≥60-year-old group had comparable outcomes and multiple regression analysis revealed that mechanism of action (MOA) was not a significant contributor to the Clinical Disease Activity Index at 12 months. CONCLUSIONS: RA patients with advanced age demonstrated distinctive clinical characteristics. The MOAs were not associated with clinical outcomes and ultrasound outcomes in RA patients with advanced age.

Association between atherosclerosis and height loss among older individuals.

Atherosclerosis and height loss are each reportedly associated with cardiovascular disease. However, no studies have found an association between atherosclerosis and height loss. A retrospective study of 2435 individuals aged 60-89 years who underwent annual health check-ups was conducted. Atherosclerosis was defined as carotid intima-media thickness (CIMT) ≥ 1.1 mm. Height loss was defined as being in the highest quintile of height decrease per year, as in our previous studies. Among study participants, 555 were diagnosed as having atherosclerosis. Independent of known cardiovascular risk factors, atherosclerosis was positively associated with height loss. The adjusted odds ratio (OR) was 1.46 (95% confidence interval, 1.15, 1.83). Essentially the same associations were observed for men and women. The adjusted OR (95% CI) was 1.43 (1.01, 2.04) for men and 1.46 (1.07, 1.99) for women. Among older individuals, atherosclerosis is associated with height loss. This result can help clarify the mechanism underlying the association between height loss and cardiovascular disease.

The impact of glucocorticoid use on the outcomes of rheumatoid arthritis in a multicenter ultrasound cohort study.

OBJECTIVE: Glucocorticoids are effective in treating rheumatoid arthritis (RA) when used appropriately considering the balance of the risks and benefits, especially at low doses. We aimed to evaluate the response of biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in patients having already been treated with glucocorticoids. METHODS: We reviewed RA patients treated with b/tsDMARDs in a prospective multicenter ultrasound cohort study. We compared the differences in the clinical characteristics at baseline and outcomes at 12 months between the two groups having been treated with and without glucocorticoids at baseline. The differences in the clinical characteristics and the treatments were balanced by the inverse probability weighting (IPW) with the propensity score. RESULTS: Of 307 patients with RA, 160 patients were treated with glucocorticoids at baseline. The median dose of glucocorticoids was equivalent to 5.0 mg/day of prednisolone. Significant differences were in age and concomitant methotrexate use, composite measures for the disease activity, and the ultrasound grayscale score at baseline. Patients treated with glucocorticoids had less frequent remissions defined by composite measures and ultrasound findings than those treated without glucocorticoids. These significant differences in the achievement of remissions remained robust even after adjusting differences in the clinical characteristics and the treatments between the two groups by IPW. CONCLUSION: RA patients treated with glucocorticoids had a higher disease activity at baseline and a poorer response to treatments with b/tsDMARDs than those without glucocorticoids. The states of patients requiring glucocorticoids might be associated with the poor response to the b/tsDMARDs.

Risk factor of non-tuberculous Mycobacterium infection in patients with rheumatoid arthritis and other autoimmune diseases receiving biologic agents: A multicenter retrospective study.

BACKGROUND: Evidence regarding the association of the usage of biologic agents (Etanercept, Tocilizumab, adalimumab and so on), such as anti-tumor necrosis factor α, with the incidence and risk factors of non-tuberculous Mycobacteria (NTM) infection is limited. Therefore, this study aimed to investigate the incidence and risk factors of NTM and their associations with biologic agents' usage, and also investigated the potential of Mycobacterium avium complex (MAC) antibodies as a predictor of NTM infection development. METHODS: This retrospective study included 672 patients with autoimmune diseases from four hospitals in Nagasaki, Japan, from January 1, 2011, to June 30, 2019, who fulfilled the inclusion criteria. RESULTS: Of the 672 patients, 9 (1.3%) developed complicated NTM infection, including two with disseminated infection, after the introduction of biologic agents. Of the nine patients, two died due to NTM infection but none tested positive for MAC antibodies prior to initiation of biologic agents. The mortality rate was higher in patients complicated with NTM than without NTM (22.2% vs 2.6%, P = 0.024). The corticosteroids dosage at the time of initiating the biologic agents was significantly higher in the NTM group than in the non-NTM group (median, 17 mg vs 3 mg, P = 0.0038). CONCLUSION: In the patients undergoing therapy with biologic agents, although NTM complication was rare, it could be fatal. In particular, for patients on a relatively high dose corticosteroids, careful observation is essential for identifying NTM complication, even if the MAC antibody test is negative.

Evaluating the safety profile of calcineurin inhibitors: cancer risk in patients with systemic lupus erythematosus from the LUNA registry-a historical cohort study.

BACKGROUND: Previous studies have shown conflicting evidence regarding the incidence of cancer in patients with systemic lupus erythematosus (SLE) compared with that in healthy individuals. Calcineurin inhibitors (CNIs) such as cyclosporine and tacrolimus have been widely used to treat SLE; however, their effects on cancer risk remain unclear. We aimed to investigate the incidence of cancer in patients with SLE and determine the potential association between CNI use and cancer risk. METHODS: The standardized incidence ratio (SIR) of cancer among patients with lupus in the Lupus Registry of Nationwide Institutions (LUNA) was calculated based on the age-standardized incidence rate of cancer reported by Japan's Ministry of Health, Labour and Welfare. We also examined the association between CNI exposure and cancer risk, while considering potential confounding factors. The analysis accounted for confounding variables such as age, sex, smoking history, maximum glucocorticoid dose, treatment history with cyclophosphamide, ongoing hydroxychloroquine, Systemic Lupus International Collaboration Clinics/American College of Rheumatology Damage Index (SDI) value (excluding cancer occurrence), comorbidity of diabetes mellitus, and smoking history. RESULTS: The study included 704 patients with SLE (625 females; 88.8%) with a median age of 44 years [interquartile range (IQR) = 34-55] years. The median past maximum glucocorticoid dose was 40 mg/day [IQR = 30-60 mg/day], and the SDI at registration was 1 [IQR = 0-2]. Among the patients, 246 (35.1%) had smoking histories, and 38 (5.4%) experienced cancer complications. Gynecological malignancies accounted for 63.2% of all cancers. The SIR of cancer in the LUNA cohort was 1.08 (95% confidence interval [CI] = 0.74-1.43). No statistically significant risks of cancer were found in relation to CNI treatment history; the odds ratio using multiple logistic regression was 1.12 (95% CI = 0.42-3.00), the risk ratio using standardization was 1.18 (95% CI = 0.47-2.16), and the risk ratio using inverse probability weighting was 1.8 (95% CI = 0.41-4.66). CONCLUSIONS: The incidence of cancer in patients with SLE in the LUNA cohort did not significantly differ from that in the general population. These findings suggest that CNI treatment in this cohort did not pose a risk factor for cancer development.

The double shared epitope: Its impact on clinical features and ultrasound findings in rheumatoid arthritis.

OBJECTIVES: The link between the HLA-DRB1 locus and the risk of rheumatoid arthritis (RA) shown in genome-wide association studies strengthens the shared epitope (SE) hypothesis. We aimed to assess the impact of the double dose of the SE (double SE) on RA and explore its clinical associations, including the response to abatacept. METHODS: We evaluated RA patients treated with csDMARDs or abatacept for HLA-DRB1 typing, clinical characteristics at baseline, and disease activity and ultrasound findings over 12 months. RESULTS: Patients with the double SE (n = 12) had significantly higher anti-citrullinated protein antibody (ACPA) titers, higher total grayscale (GS) score, and power Doppler (PD) score at baseline than patients without the double SE. Patients with the double SE exhibited reduced rates of SDAI remission and pronounced improvements in multiple disease activity between baseline and 12 months, including SDAI, CDAI, total GS score, and total PD score. When focusing on abatacept-treated patients, the decreases in SDAI, CDAI, and total PD score between baseline and 12 months were significantly larger in patients with the double SE. CONCLUSIONS: Patients with the double SE exhibited distinct characteristics, increased disease activity, and improved response to abatacept treatment.

Association between anti-thyroid peroxidase antibody and thyroid stimulating hormone: a cross-sectional study.

To maintain normal level of thyroid hormone, especially for free thyroxine (FT4), individuals with latent thyroid gland damage might have required higher thyroid stimulating hormone (TSH) than those without latent thyroid gland damage. Anti-thyroid peroxidase antibody (TPO-Ab) is a main cause of auto-immune thyroiditis, and therefore euthyroid individuals positive for TPO-Ab might have latent damage to the thyroid gland. Therefore, the association between TSH values and TPO-Ab positivity may be useful to determine the influence of latent thyroid gland damage on requirement of TSH. Furthermore, because latent damage of thyroid might elevate TSH level but not FT4 level, those associations should be observed independent from FT4. This cross-sectional study analyzed 1431 Japanese with normal ranges of free triiodothyronine (FT3) and FT4. Since TPO-Ab is associated with atherosclerosis in euthyroid individuals, cardiovascular risk factors might underlie the association between TPO-Ab and TSH values. After adjusting for FT4 and known cardiovascular risk factors, the adjusted odds ratio (95% confidence interval) of TPO-Ab positivity for logarithmic value of TSH was 1.53 (1.20, 1.95). Essentially the same association was observed when the analysis was restricted to individuals without subclinical hypothyroidism (1.54 [1.15, 2.13]). Euthyroid individuals with latent thyroid gland damage might have increased the requirement of TSH.

Profile of Nagasaki Islands Study (NaIS): A Population-Based Prospective Cohort Study on Multi-disease.

In an aging society, it is important to visualize the conditions of people living with diseases or disabilities, such as frailty and sarcopenia, and determine the environmental and genetic factors underlying such conditions. Atherosclerosis and arterial stiffness are key conditions between these factors and noncommunicable diseases. In 2014, we launched a population-based prospective open-cohort study, the Nagasaki Islands Study (NaIS), which was conducted in Goto City, located in the remote islands of Nagasaki Prefecture, Japan, mostly involving middle-aged and older residents. We conducted our own health checkups along with the annual standardized checkups organized by the municipality; recruited study participants; and started to follow-up with them for vital status (death), migration, and occurrence of diseases such as myocardial infarction, stroke, fracture, and human T-cell leukemia virus type 1 (HTLV-1) -associated uveitis. Our checkups were conducted as baseline surveys in different areas of Goto City during the fiscal years 2014-2016, secondary surveys during 2017-2019, and tertiary surveys since 2021, consisting of medical interviews, physical examinations, blood and urine tests, body composition measurements, osteoporosis screening, arterial stiffness measurements, carotid ultrasonography, and dental examination. A total of 4,957 residents participated in either the baseline or secondary surveys and were followed-up; and 3,594 and 3,364 residents (aged 27-96 and 28-98 years) participated in the baseline and secondary surveys, respectively. In conclusion, the NaIS has been undertaken to reveal the influence of aging and risk factors of noncommunicable diseases and disabilities, with an aim to contribute towards better healthcare in the future.

Serum Concentration of Growth Differentiation Factor 15 and Atherosclerosis among General Older Japanese Individuals with Normal Weight.

Growth differentiation factor 15 (GDF-15), which modulates cellular energy balance, is reported to be positively associated with cardiovascular disease. However, there have been no reports about the association between serum GDF-15 concentration and atherosclerosis as evaluated by carotid intima-media thickness (CIMT) among the general population. A cross-sectional study of 536 Japanese individuals aged 60 to 69 years was conducted. To avoid the influence of abnormal cellular energy balance, this study only included participants who had a normal body mass index (BMI) and normal thyroid hormone (free thyroxine and free triiodothyronine) levels. A significant positive association between serum GDF-15 concentration and atherosclerosis was observed. In the sex- and age-adjusted model (Model 1), the odds ratio (OR) (95% confidence interval (CI)) for the logarithmic value of GDF-15 and atherosclerosis was 2.62 (1.67, 5.87). This association remained after adjusting for thyroid function and renal function (Model 2) and further adjusting for known cardiovascular risk factors (Model 3). The corresponding values were 2.61 (1.15, 5.93) for Model 2 and 2.49 (1.08, 5.71) for Model 3, respectively. Serum GDF-15 concentrations could help us to estimate the risk of atherosclerosis by indicating the status of cellular energy balance, which is related to mitochondrial activity among comparative healthy older individuals.

Efficacy and safety of selective JAK 1 inhibitor filgotinib in active rheumatoid arthritis patients with inadequate response to methotrexate: comparative study with filgotinib and tocilizumab examined by clinical index as well as musculoskeletal ultrasound assessment (TRANSFORM study): study protocol for a randomized, open-label, parallel-group, multicenter, and non-inferiority clinical trial.

BACKGROUND: Administration of Janus kinase (JAK) inhibitors and biological disease-modifying antirheumatic drugs has dramatically improved even the clinical outcomes in patients with rheumatoid arthritis (RA) and an inadequate response to methotrexate (MTX). Dysregulation of JAK-STAT pathways via overproduction of cytokines, such as interleukin-6, is involved in the pathogenesis of RA. Filgotinib is a selective JAK1 inhibitor pending approval for use in RA. By inhibition of the JAK-STAT pathway, filgotinib is effective in suppressing disease activity and preventing the progression of joint destruction. Similarly, interleukin-6 inhibitors such as tocilizumab also inhibit the JAK-STAT pathways by inhibition of interleukin-6 signaling. We present the protocol for a study that will evaluate whether the effectiveness of filgotinib monotherapy is non-inferior to that of tocilizumab monotherapy in RA patients with an inadequate response to MTX. METHODS: This study is an interventional, multicenter, randomized, open-label, parallel-group, and non-inferiority clinical trial with a 52-week follow-up. Study participants will be 400 RA patients with at least moderate disease activity during treatment with MTX. Participants will be randomized in a 1:1 ratio to administer filgotinib monotherapy or subcutaneous tocilizumab monotherapy switched from MTX. We will evaluate disease activity by measuring clinical disease activity indices and by using musculoskeletal ultrasound (MSUS). The primary endpoint is the proportion of patients who achieve an American College of Rheumatology 50 response at week 12. Secondary endpoints are changes from baseline in the MSUS scores. We will also comprehensively analyze serum levels of multiple biomarkers, such as cytokines and chemokines. DISCUSSION: The study results are expected to show the non-inferiority of the effectiveness of filgotinib monotherapy to that of tocilizumab monotherapy in RA patients with inadequate response to MTX. The strength of this study is its prospective evaluation of therapeutic efficacy using not only clinical disease activity indices, but also MSUS, which accurately and objectively evaluates disease activity at the joint level among patients drawn from multiple centers with a standardized evaluation by MSUS. We will evaluate the effectiveness of both drugs by integrating multilateral assessments-clinical disease activity indices, MSUS findings, and serum biomarkers. TRIAL REGISTRATION: Japan Registry of Clinical Trials ( https://jrct.niph.go.jp ) jRCTs071200107. Registered on March 3, 2021. CLINICALTRIALS: gov NCT05090410. Registered on October 22, 2021.

Identification of risk factors for elevated serum IgG4 levels in subjects in a large-scale health checkup cohort study.

Introduction: To allow the identification of IgG4-related disease (IgG4-RD) from a subclinical phase as it is important to understand the risk of elevated serum IgG4 levels. We planned to evaluate serum IgG4 levels in the participants of the Nagasaki Islands Study (NaIS), a large-scale health checkup cohort study. Methods: This study included 3,240 individuals who participated in the NaIS between 2016 and 2018 and consented to participate in the study. Serum IgG4, IgG, and IgE levels and human leukocyte antigen (HLA) genotyping results of the NaIS subjects as well as lifestyle habits and peripheral blood test results were analyzed. The magnetic bead panel assay (MBA) and the standard nephelometry immunoassay (NIA) were used to measure serum IgG4 levels. The data were evaluated using multivariate analysis to identify lifestyle and genetic factors associated with elevated serum IgG4 levels. Results: Serum IgG4 levels measured with the NIA and MBA showed a tight positive correlation between the two groups (correlation coefficient 0.942). The median age of the participants in the NaIS was 69 years [63-77]. The median serum IgG4 level was 30.2 mg/dL [IQR 12.5-59.8]. Overall, 1019 (32.1%) patients had a history of smoking. When the subjects were stratified into three groups based on the smoking intensity (pack-year), the serum IgG4 level was significantly higher among those with a higher smoking intensity. Accordingly, the multivariate analysis identified a significant relationship between smoking status and serum IgG4 elevation. Conclusion: In this study, smoking was identified as a lifestyle factor correlating positively with elevated serum IgG4 levels.

Prediction of radiographic progression during a treat-to-target strategy by the sequential application of MRI-proven bone marrow oedema and power-Doppler grade ≥2 articular synovitis in rheumatoid arthritis: Retrospective observational study.

OBJECTIVES: To investigate the appropriate timing, useful findings and combination of magnetic resonance imaging (MRI) and ultrasound (US) for predicting the radiographic progression in early rheumatoid arthritis (RA). METHODS: Forty-four active RA patients, who examined by both of MRI and US in the symptomatic wrist and finger joints, were recruited in Nagasaki University Hospital from 2010 to 2017 and treated by the treat-to-target therapeutic strategy for 1 year. MRI was evaluated by RA MRI scoring and US by Outcomes Measures in Rheumatology Clinical Trial, respectively. Plain radiographs were assessed by the Genant-modified Sharp score for the symptomatic side in the same manner as MRI and US. Radiographic progression was defined as an annual increase ≥0.75 at 1 year. Factors associated with radiographic progression were analysed. Also, the optimal combination of MRI and US at each timepoint was considered. RESULTS: Logistic regression model revealed that MRI-proven bone marrow oedema at baseline and 6 months and joint counts of power-Doppler grade ≥2 articular synovitis at 3 or 6 months were significantly associated with radiographic progression at 1 year. CONCLUSION: This study may suggest the favourable timing and combination of MRI and US at each point to predict radiographic progression in patients with early-stage RA.

Immunoglobulin G4-related Disease with Marked Eosinophilia: A Case Report and Literature Review.

We encountered a 78-year-old Japanese man with IgG4-related sialoadenitis complicated with marked eosinophilia. We diagnosed him with IgG4-RD (related disease) with a submandibular gland tumor, serum IgG4 elevation, IgG4-positive plasma cell infiltration, and storiform fibrosis. During follow-up after total incision of the submandibular gland, the peripheral eosinophil count was markedly elevated to 29,480/µL. The differential diagnosis of severe eosinophilia without IgG4-RD was excluded. The patient exhibited a prompt response to corticosteroid therapy. His peripheral blood eosinophil count was the highest ever reported among similar cases. We also review previous cases of IgG4-RD with severe eosinophilia.

Height and Active Arterial Wall Thickening in Relation to Thyroid Cysts Status among Elderly Japanese: A Prospective Study.

Height is inversely associated with inflammation that stimulates endothelial repair. In our previous study involving elderly men aged 60-69 years, we found that active arterial wall thickening, which is known as the process of endothelial repair, requires CD34-positive cells. As thyroid hormone regulates CD34-positive cell production and as the absence of thyroid cysts might indicate latent damage in the thyroid, the status of thyroid cysts possibly influences the association between height and active arterial wall thickening. We conducted a 2-year follow-up study of Japanese aged 60-69 years. For participants with thyroid cysts, height was significantly inversely associated with active arterial wall thickening (thyroid function and baseline CIMT adjusted odds ratio of active arterial wall thickening for one increment of standard deviation of height (5.7 cm for men and 4.8 cm for women), 0.66 [0.49, 0.89]), while for those without thyroid cysts, a positive tendency between the two parameters was observed (1.19 [0.96, 1.50]). An inverse association between height and active arterial wall thickening was observed only for elderly participants with thyroid cysts possibly because of a supportive role of thyroid hormone, as the absence of thyroid cysts might indicate latent damage in the thyroid.

Inhibition of bone erosion, determined by high-resolution peripheral quantitative computed tomography (HR-pQCT), in rheumatoid arthritis patients receiving a conventional synthetic disease-modifying anti-rheumatic drug (csDMARD) plus denosumab vs csDMARD therapy alone: an open-label, randomized, parallel-group study.

BACKGROUND: This exploratory study compared the inhibition of bone erosion progression in rheumatoid arthritis (RA) patients treated with a conventional synthetic disease-modifying anti-rheumatic drug (csDMARD) plus denosumab versus csDMARD therapy alone and investigated the effects of denosumab on bone micro-architecture and other bone-related parameters using high-resolution peripheral quantitative computed tomography (HR-pQCT). METHODS: In this open-label, randomized, parallel-group study, patients with RA undergoing treatment with a csDMARD were randomly assigned (1:1) to continue csDMARD therapy alone or to continue csDMARDs with denosumab (60-mg subcutaneous injection once every 6 months) for 12 months. The primary endpoint was the change from baseline in the depth of bone erosion, measured by HR-pQCT, in the second and third metacarpal heads at 6 months after starting treatment. Exploratory endpoints were also evaluated, and adverse events (AEs) were monitored for safety. RESULTS: In total, 46 patients were enrolled, and 43 were included in the full analysis set (csDMARDs plus denosumab, N = 21; csDMARD therapy alone, N = 22). Most patients were female (88.4%), and the mean age was 65.3 years. The adjusted mean (95% confidence interval) change from baseline in the depth of bone erosion, measured by HR-pQCT, in the 2-3 metacarpal heads at 6 months was - 0.57 mm (- 1.52, 0.39 mm) in the csDMARDs plus denosumab group vs - 0.22 mm (- 0.97, 0.53 mm) in the csDMARD therapy alone group (between-group difference: - 0.35 mm [- 1.00, 0.31]; P = 0.2716). Similar results were shown for the adjusted mean between-group difference in the width and volume of bone erosion of the 2-3 metacarpal heads. Significant improvements in bone micro-architecture parameters were shown. The incidence of AEs and serious AEs was similar between the csDMARDs plus denosumab and the csDMARD therapy alone groups (AEs: 52.2% vs 56.5%; serious AEs: 4.3% vs 8.7%). CONCLUSIONS: Although the addition of denosumab to csDMARDs did not find statistically significant improvements in bone erosion after 6 months of treatment, numerical improvements in these parameters suggest that the addition of denosumab to csDMARDs may be effective in inhibiting the progression of bone erosion and improving bone micro-architecture. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry, UMIN000030575. Japan Registry for Clinical Trials, jRCTs071180018.

Association between Epstein-Barr virus serological reactivation and psychological distress: a cross-sectional study of Japanese community-dwelling older adults.

Reactivation of Epstein-Barr virus (EBV) is associated with the etiopathogenesis of a broad spectrum of diseases. This study aimed to investigate the association between psychological distress and EBV serological reactivation among community-dwelling older people and assess the role of sex differences in this association. This population-based cross-sectional survey was conducted among individuals who underwent annual health checkups (N = 2,821; median age 72.4 years). EBV serological reactivation was defined as elevation of EBV early antigen immunoglobulin G titers, and psychological distress was defined as Kessler 6 scores ≥5. Multivariable logistic regression analysis was performed to calculate odds ratios (OR) and 95% confidence intervals (CI) for EBV serological reactivation and psychological distress. EBV serological reactivation and psychological distress were detected in 16.4% and 8.7% of participants, respectively. Women accounted for 71% (328/463) of those with EBV serological reactivation. Multivariable logistic regression analysis showed psychological distress was not significantly associated with EBV serological reactivation among all participants (OR 1.31, 95% CI: 0.95, 1.82; P = 0.102). A sex-stratified multivariable analysis showed a positive association among women (OR 1.45, 95% CI: 1.01, 2.08; P = 0.043), but no association among men. EBV serological reactivation was independently associated with psychological distress in community-dwelling older women. The sex difference in our results warrants further investigation to clarify the physiological mechanisms underlying the association.

Association between circulating CD34-positive cell count and height loss among older men.

Height loss starting in middle age is reportedly significantly associated with death due to cardiovascular disease. Impaired blood flow is the main pathology in cardiovascular disease. Hematopoietic stem cells such as CD34-positive cells play an important role in maintaining the microcirculation and preventing impaired blood flow by activating endothelial repair and angiogenesis. Therefore, circulating CD34-positive cell count could be associated with height loss. To clarify the association between circulating CD34-positive cell count and height loss, we conducted a follow-up study of 363 Japanese men aged 60-69 years over 2 years. Height loss was defined as being in the highest quartile of height decrease per year. Independent of known cardiovascular risk factors, circulating CD34-positive cell count was significantly inversely associated with height loss. The fully adjusted odds ratio (OR) and 95% confidence interval (CI) of height loss for circulating CD34-positive cell count (logarithmic values) was 0.49 (0.32, 0.74). This study suggests that a lower capacity to maintain the microcirculation due to a fewer CD34-positive cells might affect height loss.