Metabolic syndrome in type 1 diabetes and its association with diabetes complications.

AIM: To assess the prevalence of metabolic syndrome in type 1 diabetes, and its age-related association with diabetes complications. METHODS: Australian National Diabetes Information Audit and Benchmarking (ANDIAB) was a well-established quality audit programme. It provided cross-sectional data on people attending specialist diabetes services across Australia. We determined the prevalence of metabolic syndrome (WHO criteria) in adults with type 1 diabetes and its associations with diabetes complications across age groups. RESULTS: Metabolic syndrome prevalence was 30% in 2120 adults with type 1 diabetes. Prevalence increased with age: 21% in those aged <40 years, 35% in those aged 40-60 years, and 44% in those aged >60 years (P<0.001), which was driven by an increase in hypertension rate. Metabolic syndrome was associated with a higher prevalence of microvascular, macrovascular and foot complications, with the greatest impact at a younger age. The odds ratio for macrovascular complications with metabolic syndrome, compared with without, was 5.9 (95% CI 2.1-16.4) in people aged <40 years, 2.7 (95% CI 1.7-4.2) in those aged 40-60 years, and 1.7 (95% CI 1.1-2.7) in those aged >60 years (all P < 0.05). Metformin use was higher in those with metabolic syndrome (16% vs 4%; P<0.001). CONCLUSIONS: In this large Australian cohort, metabolic syndrome was common in type 1 diabetes and identified people at increased risk of the spectrum of diabetes complications, particularly in young to middle-aged adults. Potential clinical implications are that therapies targeting insulin resistance in this high-risk group may reduce diabetes complications and should be explored.

Malnutrition in the nursing home.

PURPOSE OF REVIEW: Malnutrition in the nursing home is increasingly recognized as a major international research priority, given the expanding geriatric populations, serious consequences, and challenges conducting research in nursing homes. This review examines the recent literature and suggests implications for research and practice. RECENT FINDINGS: Across the recent studies, approximately 20% of nursing home residents had some form of malnutrition. However, malnutrition definitions were variable and prevalence ranged from 1.5 to 66.5%. Depression, cognitive impairment, functional impairment, and swallowing difficulty were consistently associated with malnutrition. Mortality was the major consequence of malnutrition among nursing home residents, whereas higher BMIs had lower risks of mortality. Beneficial interventions to reduce malnutrition in the nursing home included dietary supplements, greater resident role in food choice, and staff training programs. SUMMARY: To truly tackle the issue of malnutrition in the nursing home setting, a consistent definition is needed. We strongly recommend that an expert consensus panel identify a standard set of measures to more accurately compare the prevalence across countries. Given the mortality consequences of malnutrition and the paucity of intervention studies, research on interventions for malnutrition in the nursing home needs to be a higher priority for facilities, researchers, and funding agencies.

The effects of osteopathic manipulative treatment on pain and disability in patients with chronic low back pain: a single-blinded randomized controlled trial.

CONTEXT: The evidence for the efficacy of osteopathic manipulative treatment (OMT) in the management of low back pain (LBP) is considered weak by systematic reviews, because it is generally based on low-quality studies. Consequently, there is a need for more randomized controlled trials (RCTs) with a low risk of bias. OBJECTIVES: The objective of this study is to evaluate the efficacy of an OMT intervention for reducing pain and disability in patients with chronic LBP. METHODS: A single-blinded, crossover, RCT was conducted at a university-based health system. Participants were adults, 21-65 years old, with nonspecific LBP. Eligible participants (n=80) were randomized to two trial arms: an immediate OMT intervention group and a delayed OMT (waiting period) group. The intervention consisted of three to four OMT sessions over 4-6 weeks, after which the participants switched (crossed-over) groups. The primary clinical outcomes were average pain, current pain, Patient-Reported Outcomes Measurement Information System (PROMIS) 29 v1.0 pain interference and physical function, and modified Oswestry Disability Index (ODI). Secondary outcomes included the remaining PROMIS health domains and the Fear Avoidance Beliefs Questionnaire (FABQ). These measures were taken at baseline (T0), after one OMT session (T1), at the crossover point (T2), and at the end of the trial (T3). Due to the carryover effects of OMT intervention, only the outcomes obtained prior to T2 were evaluated utilizing mixed-effects models and after adjusting for baseline values. RESULTS: Totals of 35 and 36 participants with chronic LBP were available for the analysis at T1 in the immediate OMT and waiting period groups, respectively, whereas 31 and 33 participants were available for the analysis at T2 in the immediate OMT and waiting period groups, respectively. After one session of OMT (T1), the analysis showed a significant reduction in the secondary outcomes of sleep disturbance and anxiety compared to the waiting period group. Following the entire intervention period (T2), the immediate OMT group demonstrated a significantly better average pain outcome. The effect size was a 0.8 standard deviation (SD), rendering the reduction in pain clinically significant. Further, the improvement in anxiety remained statistically significant. No study-related serious adverse events (AEs) were reported. CONCLUSIONS: OMT intervention is safe and effective in reducing pain along with improving sleep and anxiety profiles in patients with chronic LBP.

Patient-reported outcomes of neurologic and neuropsychiatric symptoms in mild COVID-19: a prospective cohort study.

BACKGROUND: Various neurologic manifestations have been reported in patients with COVID-19, mostly in retrospective studies of patients admitted to hospital, but there are few data on patients with mild COVID-19. We examined the frequency and persistence of neurologic/neuropsychiatric symptoms in patients with mild COVID-19 in a 1-year prospective cohort study, as well as assessment of use of health care services and patient-reported outcomes. METHODS: Participants in the Alberta HOPE COVID-19 trial (hydroxychloroquine v. placebo for 5 d), managed as outpatients, were prospectively assessed 3 months and 1 year after their positive test result. They completed detailed neurologic/neuropsychiatric symptom questionnaires, the telephone version of the Montreal Cognitive Assessment (T-MoCA), the Kessler Psychological Distress Scale (K10) and the EuroQol EQ-5D-3L (measure of quality of life). Close informants completed the Mild Behavioural Impairment Checklist (MBI-C) and the Informant Questionnaire on Cognitive Decline in the Elderly. We also tracked use of health care services and neurologic investigations. RESULTS: The cohort consisted of 198 participants (87 female [43.9%] median age 45 yr, interquartile range 37-54 yr). Of the 179 participants with symptom assessments, 139 (77.6%) reported at least 1 neurologic symptom, the most common being anosmia/dysgeusia (99 [55.3%]), myalgia (76 [42.5%]) and headache (75 [41.9%]). Forty patients (22.3%) reported persistent symptoms at 1 year, including confusion (20 [50.0%]), headache (21 [52.5%]), insomnia (16 [40.0%]) and depression (14 [35.0%]); 27/179 (15.1%) reported no improvement. Body mass index (BMI), a history of asthma and lack of full-time employment were associated with the presence and persistence of neurologic/neuropsychiatric symptoms; female sex was independently associated with both (presence: odds ratio [OR] adjusted for age, race, BMI, history of asthma and neuropsychiatric history 5.04, 95% confidence interval [CI] 1.58 to 16.10). Compared to participants without persistent symptoms, those with persistent symptoms had more hospital admissions and family physician visits, and worse MBI-C scores and less frequent independence for instrumental activities at 1 year (83.8% v. 97.8%, p = 0.005). Patients with any or persistent neurologic symptoms had worse psychologic distress (K10 score ≥ 20: adjusted OR 12.1, 95% CI 1.4 to 97.2) and quality of life (median EQ-5D-3L visual analogue scale rating 75 v. 90, p < 0.001); 42/84 (50.0%) had a T-MoCA score less than 18 at 3 months, as did 36 (42.9%) at 1 year. Participants who reported memory loss were more likely than those who did not report such symptoms to have informant-reported cognitive-behavioural decline (1-yr MBI-C score ≥ 6.5: adjusted OR 15.0, 95% CI 2.42 to 92.60). INTERPRETATION: Neurologic/neuropsychiatric symptoms were commonly reported in survivors of mild COVID-19, and they persisted in 1 in 5 patients 1 year later. Symptoms were associated with worse participant- and informant-reported outcomes. Trial registration: ClinicalTrials.gov, no. NCT04329611.

How Individuals With Low Back Pain Conceptualize Their Condition: A Collaborative Modeling Approach.

Low back pain (LBP) is complex. This study aimed to use collaborative modeling to evaluate conceptual models that individuals with LBP have of their condition, and to compare these models with those of researchers/clinicians. Twenty-eight individuals with LBP were facilitated to generate mental models, using "fuzzy cognitive maps," that represented conceptualization of their own LBP and LBP "in general." "Components" (ie, causes, outcomes and treatments) related to pain, disability and quality of life were proposed, along with the weighted "Connections" between Components. Components were classified into thematic categories. Weighting of Connections were summed for each Component to judge relative importance. Individual models were aggregated into a metamodel. When considering their own condition, participants' models included 19(SD = 6) Components and 43(18) Connections with greatest weight on "Biomechanical" components. When considering LBP in general, models changed slightly. Patient models contrasted the more complex models of researchers/clinicians (25(7) Components; 77(42) Connections), with most weight on "Psychological" components. This study provides unique insight into how individuals with LBP consider their condition, which is largely biomedical and narrower than clinician/researcher perspectives. Findings highlight challenges for changing public perception of LBP, and provide a method with potential utility to understand how individuals conceptualize their condition. PERSPECTIVE: Collaborative modeling was used to understand how individuals with low back pain conceptualize their own condition, the condition in general, and compare this with models of expert researchers/clinicians. Data revealed issues in how individuals with back pain conceptualize their condition, and the method's potential utility for clinical evaluation of patients.

The effects of osteopathic manipulative treatment on pain and disability in patients with chronic neck pain: A single-blinded randomized controlled trial.

BACKGROUND: Neck pain (NP) affects up to 70% of individuals at some point in their lives. Systematic reviews indicate that manual treatments can be moderately effective in the management of chronic, nonspecific NP. However, there is a paucity of studies specifically evaluating the efficacy of osteopathic manipulative treatment (OMT). OBJECTIVE: To evaluate the efficacy of OMT in reducing pain and disability in patients with chronic NP. DESIGN: Single-blinded, cross-over, randomized-controlled trial. SETTING: University-based, osteopathic manipulative medicine outpatient clinic. PARTICIPANTS: Ninety-seven participants, 21 to 65 years of age, with chronic, nonspecific NP. INTERVENTIONS: Participants were randomized to two trial arms: immediate OMT intervention or waiting period first. The intervention consisted of three to four OMT sessions over 4 to 6 weeks, after which the participants switched groups. MAIN OUTCOME MEASURES: Primary outcome measures were pain intensity (average and current) on the numerical rating scale and Neck Disability Index. Secondary outcomes included Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29) health domains and Fear Avoidance Beliefs Questionnaire. Outcomes obtained prior to the cross-over allocation were evaluated using general linear models and after adjusting for baseline values. RESULTS: A total of 38 and 37 participants were available for the analysis in the OMT and waiting period groups, respectively. The results showed significantly better primary outcomes in the immediate OMT group for reductions in average pain (-1.02, 95% confidence interval [CI] -1.72, -0.32; p = .005), current pain (-1.02, 95% CI -1.75, -0.30; p = .006), disability (-5.30%, 95% CI -9.2%, -1.3%; p = .010) and improved secondary outcomes (PROMIS) related to sleep (-3.25, 95% CI -6.95, -1.54; p = .003), fatigue (-3.26, 95% CI -6.04, -0.48; p = .022), and depression (-2.59, 95% CI -4.73, -0.45; p = .018). The effect sizes were in the clinically meaningful range between 0.5 and 1 standard deviation. No study-related serious adverse events were reported. CONCLUSIONS: OMT is relatively safe and effective in reducing pain and disability along with improving sleep, fatigue, and depression in patients with chronic NP immediately following treatment delivered over approximately 4 to 6 weeks.

The effect of acute aerobic exercise on central arterial stiffness, wave reflections, and hemodynamics in adults with diabetes: A randomized cross-over design.

BACKGROUND: Individuals with diabetes have greater central arterial stiffness, wave reflections, and hemodynamics, all of which promote the accelerated cardiovascular pathology seen in this population. Acute aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness, wave reflections, and hemodynamics in healthy individuals; however, the effects of acute aerobic exercise in reducing these outcomes is not well established in people with diabetes. Recently, implementation of high-intensity interval exercise (HIIE) has shown superior improvements in cardiovascular health outcomes when compared to traditional aerobic exercise. Yet, the effect of HIIE on the aforementioned outcomes in people with diabetes is not known. The purpose of this study was to (i) describe the central arterial stiffness, wave reflections, and hemodynamic responses to a bout of HIIE and moderate-intensity continuous exercise (MICE) in adults with diabetes; and (ii) compare the effects of HIIE and MICE on the aforementioned outcomes. METHODS: A total of 24 adult men and women (aged 29-59 years old) with type 1 (n = 12) and type 2 (n = 12) diabetes participated in a randomized cross-over study. All participants completed the following protocols: (i) HIIE: cycling for 4 × 4 min at 85%-95% of heart rate peak (HRpeak), interspersed with 3 min of active recovery at 60%-70%HRpeak; (ii) MICE: 33 min of continuous cycling at 60%-70%HRpeak; and (iii) control (CON): lying quietly in a supine position for 30 min. RESULTS: A significant group × time effect was found for changes in central systolic blood pressure (F = 3.20, p = 0.01) with a transient reduction for the HIIE group but not for the MICE or CON groups. There was a significant group × time effect for changes in augmentation index at a heart rate of 75 beats/min (F = 2.32, p = 0.04) with a decrease following for HIIE and MICE but not for CON. For all other measures of central arterial stiffness and hemodynamics, no significant changes were observed (p > 0.05). CONCLUSION: A bout of HIIE appears to lead to a greater transient reduction in central systolic blood pressure than the reduction observed following MICE; however, both HIIE and MICE improved augmentation index at a heart rate of 75 beats/min in people with diabetes. There was no significant difference in response to HIIE and MICE in all outcomes. This provides preliminary evidence on the role of HIIE on such outcomes in people with diabetes.

Comparison of trunk proprioception between patients with low back pain and healthy controls.

OBJECTIVE: To determine whether proprioceptive impairments exist in patients with low back pain (LBP). We hypothesized that patients with LBP would exhibit larger trunk proprioception errors than healthy controls. DESIGN: Case-control study. SETTING: University laboratory. PARTICIPANTS: 24 patients with nonspecific LBP and 24 age-matched healthy controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We measured trunk proprioception in all 3 anatomical planes using motion perception threshold, active repositioning, and passive repositioning tests. RESULTS: LBP patients had significantly greater motion perception threshold than controls (P<.001) (1.3+/-0.9 degrees vs 0.8+/-0.6 degrees ). Furthermore, all subjects had the largest motion perception threshold in the transverse plane (P<.001) (1.2+/-0.7 degrees vs 1.0+/-0.8 degrees for all other planes averaged). There was no significant difference between LBP and healthy control groups in the repositioning tasks. Errors in the active repositioning test were significantly smaller than in the passive repositioning test (P=.032) (1.9+/-1.2 degrees vs 2.3+/-1.4 degrees ). CONCLUSIONS: These findings suggest that impairments in proprioception may be detected in patients with LBP when assessed with a motion perception threshold measure.

The effects of a three-week use of lumbosacral orthoses on trunk muscle activity and on the muscular response to trunk perturbations.

BACKGROUND: The effects of lumbosacral orthoses (LSOs) on neuromuscular control of the trunk are not known. There is a concern that wearing LSOs for a long period may adversely alter muscle control, making individuals more susceptible to injury if they discontinue wearing the LSOs. The purpose of this study was to document neuromuscular changes in healthy subjects during a 3-week period while they regularly wore a LSO. METHODS: Fourteen subjects wore LSOs 3 hrs a day for 3 weeks. Trunk muscle activity prior to and following a quick force release (trunk perturbation) was measured with EMG in 3 sessions on days 0, 7, and 21. A longitudinal, repeated-measures, factorial design was used. Muscle reflex response to trunk perturbations, spine compression force, as well as effective trunk stiffness and damping were dependent variables. The LSO, direction of perturbation, and testing session were the independent variables. RESULTS: The LSO significantly (P < 0.001) increased the effective trunk stiffness by 160 Nm/rad (27%) across all directions and testing sessions. The number of antagonist muscles that responded with an onset activity was significantly reduced after 7 days of wearing the LSO, but this difference disappeared on day 21 and is likely not clinically relevant. The average number of agonist muscles switching off following the quick force release was significantly greater with the LSO, compared to without the LSO (P = 0.003). CONCLUSIONS: The LSO increased trunk stiffness and resulted in a greater number of agonist muscles shutting-off in response to a quick force release. However, these effects did not result in detrimental changes to the neuromuscular function of trunk muscles after 3 weeks of wearing a LSO 3 hours a day by healthy subjects.

High-intensity interval exercise and hypoglycaemia minimisation in adults with type 1 diabetes: A randomised cross-over trial.

AIMS: We aimed to examine the feasibility and safety of undertaking high-intensity interval exercise (HIIE) with evening basal insulin dose reduction on exercise-related hypoglycaemia following an afternoon bout of HIIE, compared with moderate-intensity continuous exercise and a non-exercise control day in adults with type 1 diabetes in a free-living environment. METHODS: Twelve adults with type 1 diabetes participated in a randomised, crossover trial (9 female/3 male, mean age 40.4 ±â€¯9.9 years, duration 16.5 ±â€¯9.8 years, HbA1c 8.0 ±â€¯0.8%). Each participant undertook five conditions: a non-exercise day, and four exercise conditions on separate afternoons: a moderate-intensity continuous exercise bout; and three HIIE bouts with 10%, 20% and 30% evening basal insulin reduction. Post-exercise glucose response was measured for 24 h by continuous glucose monitoring and compared across conditions. RESULTS: HIIE with 10%, 20% and 30% evening basal insulin dose reduction was not associated with an increase in hypoglycaemia compared with moderate-intensity continuous exercise, or the non-exercise day. There was no difference in hyperglycaemia, time-in-range or glucose variability across all exercise regimens and the non-exercise day (p > .05). CONCLUSIONS: Exercise-related hypoglycaemia was not increased following afternoon HIIE when diabetes management strategies incorporating evening basal insulin dose reduction were utilised.

Effect of High-Intensity Interval Training on Glycemic Control in Adults With Type 1 Diabetes and Overweight or Obesity: A Randomized Controlled Trial With Partial Crossover.

OBJECTIVE: To study the effect of 12 weeks of high-intensity interval training (HIIT) on glycemic control in adults with type 1 diabetes and overweight or obesity. RESEARCH DESIGN AND METHODS: Thirty inactive adults with type 1 diabetes who had BMI ≥25 kg/m2 and HbA1c ≥7.5% were randomized to 12 weeks of either HIIT exercise intervention consisting of 4 × 4-min HIIT (85-95% peak heart rate) performed thrice weekly or usual care control. In a partial crossover design, the control group subsequently performed the 12-week HIIT intervention. The primary end point was the change in HbA1c from baseline to 12 weeks. Glycemic and cardiometabolic outcomes were measured at 0, 12, and 24 weeks. RESULTS: Participants were aged 44 ± 10 years with diabetes duration 19 ± 11 years and BMI 30.1 ± 3.1 kg/m2. HbA1c decreased from 8.63 ± 0.66% at baseline to 8.10 ± 1.04% at 12 weeks in the HIIT intervention group (P = 0.01); however, this change was not significantly different from the control group (HIIT -0.53 ± 0.61%, control -0.14 ± 0.48%, P = 0.08). In participants who undertook at least 50% of the prescribed HIIT intervention, the HbA1c reduction was significantly greater than control (HIIT -0.64 ± 0.64% [n = 9], control -0.14 ± 0.48% [n = 15], P = 0.04). There were no differences in insulin dose, hypoglycemia on continuous glucose monitoring, blood pressure, blood lipids, body weight, or body composition between groups. CONCLUSIONS: Overall, there was no significant reduction in HbA1c with a 12-week HIIT intervention in adults with type 1 diabetes. However, glycemic control may improve for people who undertake HIIT with greater adherence.

Development of a collaborative model of low back pain: report from the 2017 NASS consensus meeting.

BACKGROUND CONTEXT: Low back pain (LBP) is a multifactorial problem with complex interactions among many biological, psychological and social factors. It is difficult to fully appreciate this complexity because the knowledge necessary to do so is distributed over many areas of expertise that span the biopsychosocial domains. PURPOSE: This study describes the collaborative modeling process, undertaken among a group of participants with diverse expertise in LBP, to build a model to enhance understanding and communicate the complexity of the LBP problem. STUDY DESIGN: The study involved generating individual models that represented participants' understanding of the LBP problem using fuzzy cognitive mapping (FCM), and 4 subsequent phases of consultation and consensus with the participants to characterize and refine the interpretation of the FCMs. METHODS: The phases consisted of: proposal of Categories for clustering of model Components; preliminary evaluation of structure, composition and focal areas of participant's FCMs; refinement of Categories and Components with consensus meeting; generation of final structure and composition of individual participant's FCMs. Descriptive statistics were applied to the structural and composition metrics of individual FCMs to aid interpretation. RESULTS: From 38 invited contributors, 29 (76%) agreed to participate. They represented 9 disciplines and 8 countries. Participants' models included 729 Components, with an average of 25 (SD = 7) per model. After the final FCM refinement process (Components from separate FCMs that used similar terms were combined, and Components from an FCM that included multiple terms were separated), there were 147 Components allocated to ten Categories. Although individual models varied in their structure and composition, a common opinion emerged that psychological factors are particularly important in the presentation of LBP. Collectively, Components allocated to the "Psychology" Category were the most central in almost half (14/29) of the individual models. CONCLUSIONS: The collaborative modeling process outlined in this paper provides a foundation upon which to build a greater understanding and to communicate the complexity of the LBP problem. The next step is to aggregate individual FCMs into a metamodel and begin disentangling the interactions among its Components. This will lead to an improved understanding of the complexity of LBP, and hopefully to improved outcomes for those suffering from this condition.

Building a Collaborative Model of Sacroiliac Joint Dysfunction and Pelvic Girdle Pain to Understand the Diverse Perspectives of Experts.

BACKGROUND: Pelvic girdle pain (PGP) and sacroiliac joint (SIJ) dysfunction/pain are considered frequent contributors to low back pain (LBP). Like other persistent pain conditions, PGP is increasingly recognized as a multifactorial problem involving biological, psychological, and social factors. Perspectives differ between experts and a diversity of treatments (with variable degrees of evidence) have been utilized. OBJECTIVE: To develop a collaborative model of PGP that represents the collective view of a group of experts. Specific goals were to analyze structure and composition of conceptual models contributed by participants, to aggregate them into a metamodel, to analyze the metamodel's composition, and to consider predicted efficacy of treatments. DESIGN: To develop a collaborative model of PGP, models were generated by invited individuals to represent their understanding of PGP using fuzzy cognitive mapping (FCM). FCMs involved proposal of components related to causes, outcomes, and treatments for pain, disability, and quality of life, and their connections. Components were classified into thematic categories. Weighting of connections was summed for components to judge their relative importance. FCMs were aggregated into a metamodel for analysis of the collective opinion it represented and to evaluate expected efficacy of treatments. RESULTS: From 21 potential contributors, 14 (67%) agreed to participate (representing six disciplines and seven countries). Participants' models included a mean (SD) of 22 (5) components each. FCMs were refined to combine similar terms, leaving 89 components in 10 categories. Biomechanical factors were the most important in individual FCMs. The collective opinion from the metamodel predicted greatest efficacy for injection, exercise therapy, and surgery for pain relief. CONCLUSIONS: The collaborative model of PGP showed a bias toward biomechanical factors. Most efficacious treatments predicted by the model have modest to no evidence from clinical trials, suggesting a mismatch between opinion and evidence. The model enables integration and communication of the collection of opinions on PGP.

Trunk antagonist co-activation is associated with impaired neuromuscular performance.

The goal of this paper was to determine if trunk antagonist activation is associated with impaired neuromuscular performance. To test this theory, we used two methods to impair neuromuscular control: strenuous exertions and fatigue. Force variability (standard deviation of force signal) was assessed for graded isometric trunk exertions (10, 20, 40, 60, 80% of max) in flexion and extension, and at the start and end of a trunk extensor fatiguing trial. Normalized EMG signals for five trunk muscle pairs (RA rectus abdominis, EO external oblique, IO internal oblique, TE thoracic erector spinae, and LE lumbar erector spinae) were collected for each graded exertion, and at the start and end of a trunk extensor fatiguing trial. Force variability increased for more strenuous exertions in both flexion (P < 0.001) and extension (P < 0.001), and after extensor fatigue (P < 0.012). In the flexion direction, both antagonist muscles (TE and LE) increased activation for more strenuous exertions (P < 0.001). In the extension direction, all antagonist muscles except RA increased activation for more strenuous exertions (P < 0.05) and following fatigue (P < 0.01). These data demonstrate a strong relationship between force variability and antagonistic muscle activation, irrespective of where this variability comes from. Such antagonistic co-activation increases trunk stiffness with the possible objective of limiting kinematic disturbances due to greater force variability.

The effect of background muscle activity on computerized detection of sEMG onset and offset.

The performance of two computerized algorithms for the detection of muscle onset and offset was compared. The standard deviation (SD) method, a commonly used algorithm, and the approximated generalized likelihood ratio (AGLR) method, a more recently developed algorithm, were evaluated at different levels of background surface EMG (sEMG) activity. For this purpose, the amplitude ratio between the period of muscle inactivity and activity was varied from 0.125 to 1 in artificially assembled sEMG traces. In addition, 1230 real sEMG signals, obtained from various trunk muscles during quick release, were raised to a power of 3 to change their relative amplitude ratio. As the relative level of background activity increased, both the SD and AGLR methods produced longer latencies and detected fewer muscle responses, suggesting that a detection artifact can be introduced if the subject populations being compared have different levels of background muscle activity. Of the two methods, AGLR appears to be the least affected by background activity. However, above the ratio 0.8, results from AGLR are also unreliable, particularly in detecting offsets. Average latency artifacts near this ratio were 8 ms for AGLR and 46 ms for SD.

Degenerative Spondylolisthesis Is Related to Multiparity and Hysterectomies in Older Women.

STUDY DESIGN: A case-control study. OBJECTIVE: To determine whether parity and abdominal surgeries are associated with degenerative spondylolisthesis (DS). SUMMARY OF BACKGROUND DATA: DS is considered to be a major cause of low back pain (LBP) in the older population, with greater prevalence of DS among women. Because LBP and impaired abdominal muscle function are common during pregnancy and post-partum, parity-related abdominal muscle deficiency, resulting in poor spinal mechanics, could be a factor in the development of DS in women. Indeed a relationship between the number of pregnancies and DS was reported in one study. METHODS: A total of 322 women between the ages of 40 and 80 (149 with DS and 173 controls) filled out a questionnaire providing information about their demographics, the number of full-term pregnancies, the number and types of abdominal surgeries (including cesarean section and hysterectomies), and age at menopause among other items. A binary logistic regression was used as a multivariate model to identify the variables associated with DS. RESULTS: Along with age and body mass index as covariates, the number of full-term pregnancies and the hysterectomy were significant predictors of DS. Other abdominal surgeries, cesarean section, or the number of years postmenopause were not significant predictors of DS in this regression model after adjusting for all other significant variables. CONCLUSION: Each full-term pregnancy seems to be associated with the 22% increase in odds of developing DS. Hysterectomy nearly doubles the odds of DS as compared to women who did not have hysterectomy. LEVEL OF EVIDENCE: 4.

Effect of environmental exposure to hydrogen sulfide on central nervous system and respiratory function: a systematic review of human studies.

BACKGROUND: Assessment of the health effects of low-level exposure to hydrogen sulfide (H2S) on humans through experiments, industrial, and community studies has shown inconsistent results. OBJECTIVE: To critically appraise available studies investigating the effect of H2S on the central nervous system (CNS) and on respiratory function. METHODS: A search was conducted in 16 databases for articles published between January 1980 and July 2014. Two researchers independently evaluated potentially relevant papers based on a set of inclusion/exclusion criteria. RESULTS: Twenty-seven articles met the inclusion criteria: 6 experimental, 12 industry-based studies, and 10 community-based studies (one article included both experimental and industry-based studies). The results of the systematic review varied by study setting and quality. Several community-based studies reported associations between day-to-day variations in H2S levels and health outcomes among patients with chronic respiratory conditions. However, evidence from the largest and better-designed community-based studies did not support that chronic, ambient H2S exposure has health effects on the CNS or respiratory function. Results from industry-based studies varied, reflecting the diversity of settings and the broad range of H2S exposures. Most studies did not have individual measurements of H2S exposure. DISCUSSION: The results across studies were inconsistent, justifying the need for further research.

Hypoglycaemia and QT interval prolongation: Detection by simultaneous Holter and continuous glucose monitoring.

This study using simultaneous Holter and continuous glucose monitoring demonstrates that prolongation of QT interval can occur with hypoglycaemia in an ambulatory setting in people with type 1 and type 2 diabetes treated with insulin. This highlights the potential proarrhythmic harms associated with hypoglycaemia.

A mitotic cause of Whipple's triad: non-islet cell tumour hypoglycaemia in incurable low-grade malignancy.

A 74-year-old man with known metastatic haemangiopericytoma presented with neuroglycopaenic symptoms of confusion and light-headedness secondary to recurrent episodes of fasting hypoglycaemia, which resolved with oral carbohydrate intake. Investigations for hypoglycaemia revealed it to be non-insulin mediated, and subsequently due to a rare paraneoplastic phenomenon termed as non-islet cell tumour hypoglycaemia caused by tumoural overproduction of high molecular weight insulin-like growth factor-II. Despite his underlying malignancy being incurable, directed multimodality treatment involving regular oral carbohydrate intake, glucocorticoid therapy and recombinant human growth hormone was effective in relieving symptoms of hypoglycaemia. We discuss the importance of a systematic diagnostic approach to hypoglycaemia fulfilling Whipple's triad, as specific therapies can be invaluable to improving quality of life.