Margus Lember

Prof. Dr. Margus Lember

Department of Internal Medicine, University of Tartu and Tartu University Hospital, Puusepa str 8, Tartu 1014, Estonia

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 November 2019 in Medicina
Verified
Journal Article
Open access
PDF file
RMRaili Müller
Raili Müller
MKMart Kull
Mart Kull
KPKaja Põlluste
Kaja Põlluste
AVAnnika Valner
Annika Valner
Margus LemberMargus Lember
Margus Lember
RKRiina Kallikorm
Riina Kallikorm
Background and Objectives: The aim of the study was to evaluate body composition (BC) of rheumatoid arthritis (RA) patients at disease onset compared to population controls focusing on the associations between low lean mass and disease specific parameters, nutritional factors and physical activity. Materials and Methods: 91 patients with early rheumatoid arthritis (ERA) (72% female) and 328 control subjects (54% female) were studied. BC-lean and fat mass parameters were measured with a Lunar Prodigy Dual Energy X-Ray Absorptiometry (DXA) machine. The prevalence, age and gender adjusted odds ratios of having low lean mass and overfat, associations between nutrition, physical activity, and ERA disease specific parameters and the presence of low lean mass were evaluated. Results: We found that the BC of patients with recent onset RA differs from control subjects—ERA patients had a higher mean body fat percentage (BFP) and lower appendicular lean mass (ALM). 41.8% of the ERA patients and 19.8% of the controls were classified as having low lean mass adjusted OR 3.3 (95% C.I. 1.9–5.5, p < 0.001). 68.1% of the ERA subjects and 47.3% of the controls were overfat (adjusted OR 1.9 (95% C.I. 1.1–3.3, p = 0.02)) and the adjusted odds of having both low lean mass and overfat were 4.4 times higher (26.4% vs. 7.0% 95% C.I. 2.3–8.4, p < 0.001) among the ERA group. Higher ESR (OR 1.03, C.I. 1.002–1.051, p = 0.03), CRP (OR 1.03, C.I. 1.002–1.061, p = 0.04), lower protein intake (OR 0.98 C.I. 0.96–0.99, p = 0.04), corticosteroid usage (OR 3.71 C.I. 1.4–9.9, p < 0.01) and lower quality of life (higher HAQ score OR 2.41 C.I. 1.24–4.65, p < 0.01) were associated with having low lean mass in the ERA group (adjusted to age and gender). Conclusions: Patients with early RA have lower appendicular lean mass and higher body fat percentage compared to healthy controls. Loss of lean mass in early RA is associated with elevated inflammatory markers inducing catabolism, lower protein intake and also with GCS treatment.

18 July 2023 in Medicina
Verified
Journal Article
Open access
PDF file
KKKati Kärberg
Kati Kärberg
AFAlastair Forbes
Alastair Forbes
Margus LemberMargus Lember
Margus Lember
Background and Objectives: The role of adipokines in the development of atherosclerosis in type 2 diabetes (T2DM) has not yet been fully elucidated. The effects of drugs on adipokine concentrations have only been evaluated in very few studies, although they may be of clinical importance. This study aimed to assess whether the concentrations of circulating adipokines could predict subclinical atherosclerosis in patients with T2DM, as well as their interactions with commonly used cardiovascular drugs. Materials and Methods: Our population-based cross-sectional multicentric study included 216 participants with T2DM but without previously diagnosed atherosclerosis. The carotid artery intima–media thickness (IMT), plaque and ankle–brachial index (ABI) metrics were measured. Resistin, visfatin, retinol-binding protein 4, high molecular weight adiponectin and leptin levels were evaluated using Luminex’s xMAP technology. Results: Visfatin and resistin concentrations correlated positively with IMT (p = 0.002 and p = 0.009, respectively). The correlation of visfatin to IMT ≥ 1.0 mm was significant in males (p < 0.001). Visfatin had a positive correlation with IMT ≥ 1.0 mm or plaque (p = 0.008) but resistin only correlated with plaque (p = 0.049). Visfatin predicted IMT ≥ 1.0 mm or plaque in patients on β-blocker monotherapy (p = 0.031). Visfatin lost its ability to predict subclinical atherosclerosis in patients taking angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium channel blockers or statins. After adjustments for risk factors for atherosclerosis and cardiovascular drugs, visfatin maintained an independent association with mean IMT (p = 0.003), IMT ≥ 1.0 mm or plaque (p = 0.005) and ABI ≤ 0.9 (p = 0.029). Conclusions: Visfatin could be used as a marker of subclinical atherosclerosis in patients with T2DM, especially in males. The assessment of visfatin concentration could aid in identifying individuals who could benefit from implementing preventive measures against atherosclerosis.

26 May 2022 in Clinical Nutrition ESPEN
Verified
Journal Article
Closed access
KKKati Kärberg
Kati Kärberg
AFAlastair Forbes
Alastair Forbes
Margus LemberMargus Lember
Margus Lember

28 May 2025 in Medicina
Verified
Journal Article
Open access
PDF file
AKAnne Kallaste
Anne Kallaste
KKKalle Kisand
Kalle Kisand
AAAgnes Aart
Agnes Aart
ASAhto Salumets
Ahto Salumets
KKKalle Kisand
Kalle Kisand
Margus LemberMargus Lember
Margus Lember
Background: SARS-CoV-2 infection can lead to persistent or newly emerging symptoms lasting for months, a condition known as long COVID (LC). The pathophysiology of LC remains poorly understood, with cytokine dysregulation proposed as a key mechanism, although findings across the studies have been inconsistent. Patients and methods: We conducted a longitudinal study using the Olink® Target 96 Inflammation Panel to assess cytokines in COVID-19 (COV) patients at three months and six months post-infection. These profiles were compared with those of individuals recovering from other upper respiratory tract infections (non-COV). Additionally, we analyzed differences between individuals with LC and those who recovered from COVID-19. Predictive models for LC at three months and sixth months post-infection were developed using inflammatory markers and relevant clinical cofactors, including gender, age, BMI, hemogram, Β2-microglobulin, D-dimers, LDH, AST, ALT, Ferritin, vitamin D, CRP, and the severity of acute COVID-19 infection as classified by WHO criteria. Results: We observed a general decline in inflammatory biomarkers in post-COVID-19 patients over time, with only a few cytokines elevated (CCL4 at month 3 and CST5 at month 6) compared to non-COV controls. In LC patients, an early phase of low-grade inflammation transitioned into significant reduction in proinflammatory biomarkers compared to recovered individuals. Rather than indicating immune normalization, this pattern suggests a possible suppression or exhaustion of the immune response in the months following acute infection. Importantly, our predictive modeling demonstrated that this specific cytokine signature, in combination with acute disease severity and clinical cofactors, described well the presence of LC. Conclusions: Our findings suggest that inflammation-related biomarker dysregulation following acute SARS-CoV-2 infection evolves dynamically over a six-month period. By the sixth month, compared to the third month, the presence of LC is more accurately predicted by a combination of persistent biomarker alteration and the severity of the initial infection, as defined by WHO criteria. This represents a novel insight, as previous studies have primarily associated LC with elevated proinflammatory markers, whereas our results suggest that immune suppression or exhaustion may play a more prominent role in the later stages.

6 March 2024 in Medicina
Verified
Journal Article
Open access
PDF file
KKKati Kärberg
Kati Kärberg
AFAlastair Forbes
Alastair Forbes
Margus LemberMargus Lember
Margus Lember
Background and Objectives. Optimal nutrition for type 2 diabetes (T2DM) aims to improve glycemic control by promoting weight loss and reducing adipose tissue, consequently improving cardiovascular health. Dietary alterations can influence adipose tissue metabolism and potentially impact adipocytokines like visfatin, thereby affecting atherosclerosis development. This study aimed to investigate dietary habits and adherence to recommendations among individuals with T2DM and to examine how dietary adherence influences the association between visfatin and subclinical atherosclerosis. Materials and Methods: This cross-sectional multicenter study involved 216 adults (30–70 years) with T2DM, assessing dietary habits, adherence to recommendations (carbohydrates, fats, protein, fiber, saturated fatty acid, polyunsaturated and monounsaturated fatty acid (PUFA and MUFA) and salt), and the association between visfatin and subclinical atherosclerosis. Participants completed 24 h dietary recalls; dietary misreporting was assessed using the Goldberg cut-off method. Carotid intima–media thickness (IMT) and plaque occurrence were evaluated with ultrasound, while visfatin levels were measured using Luminex’s xMAP technology. Results: Three of the eight recommendations were followed in 31% of subjects, two in 26%, and four in 20%, with the highest adherence to MUFA and protein intake. Significant correlations between IMT and visfatin were observed in individuals with specific dietary patterns. The association between IMT and visfatin persisted when PUFA and MUFA intake aligned with recommendations. PUFA intake ≤ 10% and MUFA ≤ 20% of total energy significantly correlated with carotid artery IMT (p = 0.010 and p = 0.006, respectively). Visfatin’s associations with IMT remained significant (p = 0.006) after adjusting for common risk factors, medication use, and dietary nonadherence. No association was observed with carotid artery plaque. Conclusions: Dietary compliance was limited, as only 31% adhered even to three of eight recommendations. A common dietary pattern characterized by low carbohydrate and fiber but high fat, total fat, saturated fat, and salt intake was identified. This pattern amplifies the statistical association between visfatin and subclinical atherosclerosis.

28 March 2021 in Medicina
Verified
Journal Article
Open access
PDF file
AVAnnika Valner
Annika Valner
ÜKÜlle Kirsimägi
Ülle Kirsimägi
RMRaili Müller
Raili Müller
MKMart Kull
Mart Kull
KPKaja Põlluste
Kaja Põlluste
RKRiina Kallikorm
Riina Kallikorm
Background and Objectives: The aim of this study was to assess if there are structural and functional changes of hands and legs already in early rheumatoid arthritis (ERA), compared with the population-based control group. Additionally, we aimed to identify if the changes are symmetrical in hands and legs and if there are factors that are associated with these changes. The study was conducted, and, thus far, the results have been controversial. Materials and Methods: The study group consisted of 83 consecutive patients with ERA and 321 control subjects. Dual-Energy X-Ray Absorptiometry (DXA) machine was used to measure bone, lean and fat mass. Inflammation and bone markers, smoking and nutritional habits were assessed, to evaluate the effects of different factors. The 30-Second Chair Stand Test (30-CST) and the Handgrip Strength Test (HST) were used to estimate muscle strength. Results: The presence of ERA was associated with lower arm, leg lean mass and higher fat mass of arm, compared with control subjects. ERA was also associated with lower mean handgrip in HST and worse muscle strength of legs in the 30-CST. Bone mass changes were not so evident both in arms and legs. Smoking habits did not seem to have relevant effect on bone mass, muscle structural and functional changes, both on hands and legs. In ERA, lean mass of arm and leg was negatively associated with C-reactive protein (CRP). The intake of proteins in ERA was not associated with lean mass changes both in hands and legs. Conclusions: Structural and functional changes of hands and legs are different in ERA. ERA patients had higher fat mass of arm, lower lean mass of arm and leg and, accordingly, decreased muscle function. The lowering of lean mass of arm and leg in ERA was associated with the elevation of CRP.