Sarcopenia increases the risk for mortality in patients who undergo amputation for diabetic foot

Transcriptome sequencing and bioinformatics analysis of gastrocnemius muscle in type 2 diabetes mellitus rats

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is one of the high risk factors for sarcopenia. However, the pathogenesis of diabetic sarcopenia has not been fully elucidated. This study obtained transcriptome profiles of gastrocnemius muscle in normal and T2DM rats based on high-throughput sequencing technology, which may provide new ideas for exploring the pathogenesis of diabetic sarcopenia.

METHODS

Twelve adult male Sprague-Dawley rats were randomly divided into Control group and T2DM group, and gastrocnemius muscle tissue was retained for transcriptome sequencing and real-time quantitative polymerase chain reaction (qRT-PCR) 6 months later. Screening differentially expressed genes (DEGs), Cluster analysis, gene ontology (GO) functional annotation analysis and Kyoto Encyclopedia of Genes and Gnomes (KEGG) functional annotation and enrichment analysis were performed for DEGs. Six DEGs related to apoptosis were selected for qTR-PCR verification.

RESULTS

Transcriptomic analysis showed that there were 1016 DEGs between the gastrocnemius muscle of T2DM and normal rats, among which 665 DEGs were up-regulated and 351 DEGs were down-regulated. GO analysis showed that the extracellular matrix organization was the most enriched in biological processes, with 26 DEGs. The extracellular matrix with 35 DEGs was the most abundant cellular component. The extracellular matrix structural constituent, with 26 DEGs, was the most enriched in molecular functions. The highest number of DEGs enriched in biological processes, cellular components and molecular functions were positive regulation of transcription by RNA polymerase II, nucleus and metal ion binding, respectively. There were 78, 230 and 89 DEGs respectively. KEGG pathway enrichment analysis showed that ECM-receptor interaction, PI3K-Akt signaling pathway and TGF-β signaling pathway(p < 0.001) had higher enrichment degree and number of DEGs. qRT-PCR results showed that the fold change of Map3k14, Atf4, Pik3r1, Il3ra, Gadd45b and Bid were 1.95, 3.25, 2.97, 2.38, 0.43 and 3.6, respectively. The fold change of transcriptome sequencing were 3.45, 2.21, 2.59, 5.39, 0.49 and 2.78, respectively. The transcriptional trends obtained by qRT-PCR were consistent with those obtained by transcriptome sequencing.

CONCLUSIONS

Transcriptomic analysis was used to obtain the "gene profiles" of gastrocnemius muscle of T2DM and normal rats. qRT-PCR verification showed that the genes related to apoptosis were differentially expressed. These DEGs and enrichment pathways may provide new ideas for exploring the pathogenesis of diabetic sarcopenia.

Barriers and Facilitators to Cardiovascular Rehabilitation Programmes for People with Lower Limb Amputation: A Survey of Clinical Practice in Canada

Purpose

This study determines barriers and facilitators to including people with lower limb amputation (LLA) in cardiovascular rehabilitation programmes (CRPs).

Method

Canadian CRP managers and exercise therapists were invited to complete a questionnaire.

Results

There were 87 respondents. Of the 32 CRP managers, 65.6% reported that people with LLA were eligible for referral, but of these, 61.9% only accepted people with LLA and cardiac disease, and 38.1% only accepted them with ≥ 1 cardiovascular risk factor. CRP eligibility progressively decreased as mobility severity increased, with 94% of programmes accepting those with mild mobility deficits but only 48% accepting those with severe deficits. Among therapists in CRPs that accepted LLAs, 54.3% reported not having an LLA participant within the past three years. Among all responding therapists and managers who were also therapists (n = 58), 43% lacked confidence in managing safety concerns, and 45%, 16%, and 7% lacked confidence in prescribing aerobic exercise to LLA with severe, moderate, and no mobility deficits respectively. There was a similar finding with prescribing resistance training. LLA-specific education had not been provided to any respondent within the past three years. The top barriers were lack of referrals (52.6%; 30) and lack of knowledge of the contraindications to exercise specific for LLA (43.1%; 31). Facilitators included the provision of a resistance-training tool kit (63.4%; 45), education on exercise safety (63.4%; 45), and indications for physician intervention/inspection (63.6%; 42).

Conclusion

Most of the CRPs surveyed only accept people with LLA if they have co-existing cardiac disease or cardiovascular risk factors. Few people with LLA participate. Education on CRP delivery for LLAs is needed to improve therapists' confidence and exercise safety.

Initial handgrip strength as a predictive factor for amputation risk in diabetic foot patients

BACKGROUND

We aimed to analyze the prognostic significance of handgrip strength as predictor of lower extremity amputation at 1 year follow up in patients with type 2 diabetes.

METHODS

We evaluated 526 patients with type 2 diabetes between August 2020, and, June 2022. We collected from the electronic medical records demographic variables, laboratory data and history of amputation. The handgrip strength was assessed using a handheld Smedley digital dynamometer following the NHANES Muscle Strenght/Grip Test Procedure. Low handgrip strength was defined for women as less than 16 kg and for men less than 27 kg. Outcome variable was major or minor lower extremity amputation.

RESULTS

A total of 205 patients with complete data entered the study. Patients mean age was 59 years old, 37% were women and the mean diabetes disease duration was 14 years. Seventy-seven (37%) patients suffered from lower extremity mputations (26 major and 51 minor amputations). After controlling for age, gender, presence of peripheral artery disease, body mass index and white cell counts as confounder variables, patients with low handgrip had an increased risk for amputations (Odds Ratio 2.17; 95% confidence Interval: 1.09-4.32; <0.001).

CONCLUSION

Low handgrip stregth is an independent prognostic marker for lower limb amputation at one year in patients with diabetes.

A scoping review on nutritional intake and nutritional status in people with a major dysvascular lower limb amputation

PURPOSE

To systematically review literature on nutritional intake, nutritional status and nutritional interventions, and to study their association with short- and long-term clinical outcomes in people with a major dysvascular lower limb amputation.

METHODS

PubMed, Ovid, CINAHL, and The Cochrane Library were searched. Studies were included if nutritional intake, nutritional status, or nutritional interventions in people with a major dysvascular lower limb amputation were analyzed.

RESULTS

Of the 3038 unique papers identified, 30 studies were included. Methodological quality was moderate (1 study) or weak (29 studies). Limited information was available on nutritional intake (2 studies) and nutritional interventions (1 study). Nutritional intake and nutritional status were assessed by diverse methods. The percentage of people with a poor nutritional status ranged from 1% to 100%. In some studies, measures of poor nutritional status were associated with adverse short- and long-term clinical outcomes.

CONCLUSIONS

The percentage of people with a poor nutritional status is inconclusive in the major dysvascular lower limb amputation population, because of the heterogeneity of the assessment methods used. Some included studies reported a negative association between poor nutritional status and clinical outcomes. However, these results should be interpreted with caution, because of the limited quality of the studies available. Studies high in methodological quality and high in hierarchy of evidence are needed.IMPLICATIONS FOR REHABILITATIONThe proportion of people with a poor nutritional status in the major dysvascular lower limb amputation population is inconclusive.Poor nutritional status seems to affect clinical outcomes negatively.More uniformity in assessment of malnutrition in the major dysvascular lower limb amputation population is needed.

Analysis of the Relationship Between Lower leg Muscle Mass and Preservation of Lower Extremity in Patients with Diabetic Foot Ulcer

This study aimed to determine how the muscle mass of the lower leg affects the preservation of the lower extremities in patients with diabetic foot ulcer. This study analyzed patients with diabetic foot ulcer between January 2014 and June 2018 with a follow-up of at least 2 years. Of these 181 patients whose ulcer is located distal to the metatarsophalangeal joint, which was categorized as grade ≤2 by the Wagner classification were classified into 4 grades: grade 0 (treated without amputation), grade 1 (amputation distal to the metatarsophalangeal joint), grade 2 (Ray, transmetatarsal, Lisfranc, and Chopart amputation), and grade 3 (Syme, below-knee, and above-knee amputation) according to the final amputation degree. The muscles of the lower leg were classified into 4 compartments: anterior, lateral, deep posterior, and superficial posterior. The cross-sectional area and attenuation to estimate the muscle volume and density were measured at the axial image of computed tomography (CT) angiography. No significant differences were observed in the sex ratio and mean age among the grades (P = .966 and .962). The cross-sectional area of the anterior, lateral, and posterior compartments demonstrated no significant differences, but that of the superficial posterior compartment exhibited significant differences among the grades (P < .001). Moreover, the attenuation of the anterior, lateral, and deep posterior compartments showed no significant differences, but that of the posterior compartment showed significant differences among the grades (P = .003). The muscle mass of the superficial posterior compartment of the lower leg could be a good indicator of the preservation of the lower extremity in patients with diabetic foot ulcer. Therefore, a strengthening exercise for the triceps surae and plantaris muscles in the early stage could help preserve as much of the lower extremities as possible.

Indications of musculoskeletal health in deceased male individuals with lower-limb amputations: comparison to non-amputee and diabetic controls

Individuals with lower-limb amputations, many of whom have type 2 diabetes, experience impaired musculoskeletal health. This study: (1) compared residual and intact limbs of diabetic and non-diabetic post-mortem individuals with amputation to identify structures vulnerable to injury, and (2) compared findings to diabetic and healthy control groups to differentiate influences of amputation and diabetes on musculoskeletal health. Postmortem CT scans of three groups, ten individuals each, were included: (1) individuals with transtibial or transfemoral amputations, half with diabetes (2) diabetic controls, and (3) healthy controls. Hip and knee joint spaces, cross-sectional thigh muscle and fat areas, and cross-sectional bone properties (e.g. area, thickness, geometry) were measured. Wilcoxon Signed-Rank and Kruskal-Wallis tests assessed statistical significance. Asymmetry percentages between limbs assessed clinical significance. Residual limbs of individuals with amputation, particularly those with diabetes, had significantly less thigh muscle area and thinner distal femoral cortical bone compared to intact limbs. Compared to control groups, individuals with amputation had significantly narrower joint spaces, less thigh muscle area bilaterally, and thinner proximal femoral cortical bone in the residual limb. Diabetic individuals with amputation had the most clinically significant asymmetry. Findings tended to align with those of living individuals. However, lack of available medical information and small sample sizes reduced the anticipated clinical utility. Larger sample sizes of living individuals are needed to assess generalizability of findings. Quantifying musculoskeletal properties and differentiating influences of amputation and diabetes could eventually help direct rehabilitation techniques.

Sarcopenia is an independent risk factor for all-cause mortality rate in patients with diabetic foot ulcers

Objective

This study aimed to determine whether sarcopenia affects the all-cause mortality rate of patients with diabetic foot ulcers (DFUs).

Research design and methods

The clinic-based observational study included 217 patients treated at the Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University during a 4-year period. All subjects underwent dual-energy X-ray absorptiometry to determine their body composition during hospitalization. Diagnosis of sarcopenia was based on the Baumgartner diagnostic criteria. Patients were followed up regularly by phone calls until April 1, 2019, and their survival status was recorded.Univariate and multivariate Cox risk ratio regression models were used to analyze factors influencing the all-cause mortality rate of patients with DFUs.

Results

Of the 217 patients, 158 people survived (82.7%), 33 died (17.3%), and 26 were lost to follow-up. The median follow-up time was 23 (Range 11-34) months. The majority of patients were male (68.6%), with a mean age of 67.29 ± 11.14 years. The 5-year survival rate was 68.3% and 45.9% for all study patients (n = 217) and sarcopenia patients (n = 81), respectively. Multivariate Cox risk regression model showed that age (HR 1.042[95%CI:1.006, 1.078], P = 0.021), sarcopenia (HR 5.051[95%CI:1.968, 12.961], P = 0.001), and serum creatinine (HR 1.007[95%CI: 1.003, 1.010], P < 0.001) were independent risk factors for all-cause mortality rate of patients with DFUs. Kaplan-Meier survival curve indicated that the survival rate of patients with sarcopenia was significantly lower than non-sarcopenia patients (P < 0.001).

Conclusions

Sarcopenia is an independent risk factor for all-cause mortality of patients with DFUs and hence an important prognostic factor for patients with DFUs. Active prevention and improvement of sarcopenia can potentially improve the survival outcomes of this patient population.

Sarcopenia, Frailty and Diabetic Foot: A Mini Narrative Review

The aim of this narrative mini review was to investigate the potential association of the diabetic foot (DF) with sarcopenia and frailty. Data is still limited, but it appears that DF patients may be more prone to frailty. In addition, patients with DF and sarcopenia exhibit more frequently foot ulcers and amputations, as well as increased mortality rates post-operatively. Further studies are now needed to see how these realizations may be used in clinical practice, aiming to improve DF outcomes.

Foot Ulcer and Risk of Lower Limb Amputation or Death in People With Diabetes: A National Population-Based Retrospective Cohort Study

OBJECTIVE

To describe incidence of foot ulceration and amputation-free survival associated with foot ulceration status in a national population-based cohort study of people with diabetes.

RESEARCH DESIGN AND METHODS

The study population included 233,459 people with diabetes who were alive in Scotland on 1 January 2012 identified from the national population-based register (national prevalence 4.9%). Characteristics of patients identified from linked hospital and mortality records during follow-up to the end of November 2017 were compared by outcome. Cox regression was used to assess the association between history of foot ulcer and amputation-free survival.

RESULTS

The population included 23,395 people with type 1 diabetes and 210,064 people with type 2 diabetes. In total there were 13,093 (5.6%) people who had a previous foot ulceration, 9,023 people who developed a first ulcer, 48,995 who died, and 2,866 who underwent minor or major amputation during follow-up. Overall incidence of first-time foot ulcers was 7.8 per 1,000 person-years (95% CI7.6-7.9) and 11.2 (11.0-11.4) for any ulcer. Risk factors for reduced amputation-free survival included social deprivation, mental illness, and being underweight in addition to conventional cardiovascular risk factors. Adjusted hazard ratios (95% CI) were 2.09 (1.89-2.31) for type 1 diabetes and 1.65 (1.60-1.70) for type 2 diabetes.

CONCLUSIONS

The overall incidence of foot ulceration in a population-based study of people with diabetes was 11.2 per 1,000 person-years. Foot ulceration is associated with lower amputation-free survival rate, a potential measure of effectiveness of care among people with diabetes. Mental illness and social deprivation are also highlighted as risk factors.

Re-amputation in patients with diabetes-related minor amputations who underwent physical therapy during their hospitalization

Background

Diabetes-related foot lesions are a major cause of non-traumatic lower limb amputations and are associated with a high re-amputation rate. Lesions can cause hindrance in activities of daily living, reduce physical function, and lower a patient’s quality of life. Physical therapy is necessary to prevent these limitations. Thus far, there has been limited investigation into the re-amputation rate in patients who have undergone physical therapy. This study aimed to elucidate modifiable risk factors for re-amputation in patients with minor amputations who were treated with physical therapy during their hospitalization.

Methods

This was a retrospective cohort study of 245 consecutive hospitalized patients who presented to our Wound Care Center between January 2015 and February 2018 and received physical therapy after a minor amputation. Participants were identified from admission records to surgical and physical therapy units stored in the electronic medical records. We examined re-amputations that occurred in the ipsilateral lower extremity during the 1-year post-discharge outpatient period. The maximum follow-up period was set at 1 year. We used Cox proportional hazards analysis to examine factors affecting the risk of re-amputation.

Results

Of the 129 patients enrolled, 42 patients (32.5%) underwent re-amputations during an average observation period of 6.2 months (range, 2.1 to 10.9 months). The factors associated with re-amputation were a requirement for hemodialysis, ankle dorsiflexion angle, and the Functional Independence Measure (FIM) ambulation score.

Conclusions

In diabetes patients with minor amputations, a requirement for hemodialysis, ankle dorsiflexion angle, and the FIM ambulation score were shown to be modifiable risk factors for re-amputation. This emphasizes that maintaining vascular endothelial function through lower limb muscle exercises for hemodialysis, improving ankle mobility, and relieving plantar pressure during walking are necessary to reduce the risk of re-amputation. Patients with these risk factors should be encouraged to participate in physical therapy.

A Narrative Review on Sarcopenia in Type 2 Diabetes Mellitus: Prevalence and Associated Factors

Type 2 diabetes mellitus (T2DM) represents a major health burden for the elderly population, affecting approximately 25% of people over the age of 65 years. This percentage is expected to increase dramatically in the next decades in relation to the increased longevity of the population observed in recent years. Beyond microvascular and macrovascular complications, sarcopenia has been described as a new diabetes complication in the elderly population. Increasing attention has been paid by researchers and clinicians to this age-related condition—characterized by loss of skeletal muscle mass together with the loss of muscle power and function—in individuals with T2DM; this is due to the heavy impact that sarcopenia may have on physical and psychosocial health of diabetic patients, thus affecting their quality of life. The aim of this narrative review is to provide an update on: (1) the risk of sarcopenia in individuals with T2DM, and (2) its association with relevant features of patients with T2DM such as age, gender, body mass index, disease duration, glycemic control, presence of microvascular or macrovascular complications, nutritional status, and glucose-lowering drugs. From a clinical point of view, it is necessary to improve the ability of physicians and dietitians to recognize early sarcopenia and its risk factors in patients with T2DM in order to make appropriate therapeutic approaches able to prevent and treat this condition.

Relationship of Sarcopenia with Microcirculation Measured by Skin Perfusion Pressure in Patients with Type 2 Diabetes

BACKGROUND

Few studies have examined the relationship of sarcopenia with the microcirculation. The current study investigated the relationship of sarcopenia with microcirculatory function, as assessed by skin perfusion pressure (SPP), in type 2 diabetes mellitus (T2DM) patients.

METHODS

In total, 102 T2DM patients who underwent SPP measurements and bioelectrical impedance analysis (BIA) were enrolled in this cross-sectional study. SPP was assessed using the laser Doppler technique. Sarcopenia was defined as low height-adjusted appendicular muscle mass (men, &lt;7 kg/m2; women, &lt;5.7 kg/m2) using BIA. We divided the participants into two groups based on SPP (≤50 and &gt;50 mm Hg), and an SPP below 50 mm Hg was considered to reflect impaired microcirculation.

RESULTS

Fourteen patients (13.7%) were diagnosed with impaired microcirculatory function of the lower limb based on SPP. The prevalence of sarcopenia in all subjects was 11.8%, but the percentage of patients with an SPP ≤50 mm Hg who had sarcopenia was more than triple that of patients with an SPP &gt;50 mm Hg (28.6% vs. 9.1%, P=0.036). A significant positive correlation was found between SPP and appendicular muscle mass adjusted for height (P=0.041 for right-sided SPP). Multiple logistic regression analysis showed that patients with sarcopenia had an odds ratio of 4.1 (95% confidence interval, 1.01 to 24.9) for having an SPP ≤50 mm Hg even after adjustment for confounding factors.

CONCLUSION

These results suggest that sarcopenia may be significantly associated with impaired microcirculation in patients with T2DM. Nonetheless, the small number of patients and wide CI require cautious interpretation of the results.

Prevalence and temporal trends of presarcopenia metrics and related body composition measurements from the 1999 to 2006 NHANES

OBJECTIVE

To evaluate the prevalence and temporal trends of presarcopenia and related body composition measurements.

DESIGN

Cross-sectional study.

SETTING

National Health and Nutrition Examination Survey (NHANES) 1999-2006.

METHODS

Presarcopenia was defined according to the guidelines from the European Working Group on Sarcopenia. Logistic or linear regression models were used to evaluate the linear trend of the prevalence of presarcopenia, obesity and related body composition measurements.

PARTICIPANTS

A total of 29 947 participants aged 18-90 years from five waves of the NHANES were included in the analysis.

OUTCOME MEASURES

Presarcopenia was sex-specifically defined as having a skeletal mass index ≤7.26 kg/m² in men and ≤5.5 kg/m² in women. Body composition measurements, including total body fat percentage, total body fat mass, total lean body mass, appendicular skeletal muscle mass and bone mineral density, were obtained by dual-energy X-ray absorptiometry.

RESULTS

The overall prevalence of presarcopenia ranged from 16.4% in 1999-2000 to 14.8% in 2005-2006 (p for trend=0.78). Presarcopenia was stable in both males (p for trend=0.36) and females (p for trend=0.20). The presarcopenia prevalence was significantly elevated among the age group of 18-39 years old (from 11.3% to 14.1%, p for trend=0.04) and among non-Hispanic blacks (p for trend <0.001). Adults aged ≥80 years old had the highest prevalence.

CONCLUSIONS

The prevalence of presarcopenia increased among young individuals over time. Non-Hispanic blacks also demonstrated an increasing trend in the prevalence over time.

Five year mortality and direct costs of care for people with diabetic foot complications are comparable to cancer

BACKGROUND

In 2007, we reported a summary of data comparing diabetic foot complications to cancer. The purpose of this brief report was to refresh this with the best available data as they currently exist. Since that time, more reports have emerged both on cancer mortality and mortality associated with diabetic foot ulcer (DFU), Charcot arthropathy, and diabetes-associated lower extremity amputation.

METHODS

We collected data reporting 5-year mortality from studies published following 2007 and calculated a pooled mean. We evaluated data from DFU, Charcot arthropathy and lower extremity amputation. We dichotomized high and low amputation as proximal and distal to the ankle, respectively. This was compared with cancer mortality as reported by the American Cancer Society and the National Cancer Institute.

RESULTS

Five year mortality for Charcot, DFU, minor and major amputations were 29.0, 30.5, 46.2 and 56.6%, respectively. This is compared to 9.0% for breast cancer and 80.0% for lung cancer. 5 year pooled mortality for all reported cancer was 31.0%. Direct costs of care for diabetes in general was $237 billion in 2017. This is compared to $80 billion for cancer in 2015. As up to one-third of the direct costs of care for diabetes may be attributed to the lower extremity, these are also readily comparable.

CONCLUSION

Diabetic lower extremity complications remain enormously burdensome. Most notably, DFU and LEA appear to be more than just a marker of poor health. They are independent risk factors associated with premature death. While advances continue to improve outcomes of care for people with DFU and amputation, efforts should be directed at primary prevention as well as those for patients in diabetic foot ulcer remission to maximize ulcer-free, hospital-free and activity-rich days.

Transmetatarsal amputation: A 12 year retrospective case review of outcomes

BACKGROUND

Diabetic foot pathology has rapidly increased, presenting a vast economic burden with severe implications for patients. Establishing effective limb salvage techniques such as transmetatarsal amputation is essential to offer viable alternatives to major limb amputation in severe foot infection, where outcomes are variable and mortality rates high.

METHODS

A retrospective review of outcomes was performed on patients who underwent TMA at a single United Kingdom hospital between 2005-2017. Healing rate and time to healing, mortality, duration of hospital admission and incidence of revision surgery was evaluated. Forty-seven patients had 54 TMA's by the Podiatric Surgery team. Data was assessed for Mean (SD) and Median. The impact of co-morbidities was considered and the perioperative and surgical management reviewed to identify techniques which may improve outcomes.

RESULTS

A 78% healing rate was achieved. Six patients (11%) died before healing. The aremaining 11% did not heal and resulted in major limb amputation. No further surgery to the same foot was required after the TMA healed. A Median healing time of 83 days was identified and the Median duration of hospital admission was 24 days. Adjunctive wound care products may to have a positive impact on these factors. Five-year mortality was 43%, and demonstrated an association with renal and/or vascular pathology. All patients had diabetes, with many also having Peripheral Vascular Disease (PVD). Almost all TMA's failing to heal had PVD. The presence and severity of renal disease also seemed to have a negative impact on wound healing.

CONCLUSION

Positive healing and mortality rates with low need for revision surgery support TMA to be an effective alternative to major limb amputation. Adjunctive agents may have a positive impact on wound healing and length of hospital admission. Skilled surgical technique and Multidisciplinary work is essential for positive long-term outcomes and cost-effective care.