Maximal aerobic power in patients with chronic low back pain: a comparison with healthy subjects

The objective of the study was to compare the maximal aerobic capacity of patients with chronic low back pain with healthy asymptomatic controls matched for age, gender and level of physical activity at work and during sports activities. Reported data in the literature with respect to aerobic capacity in patients with chronic low back pain are not conclusive. Nevertheless, based on the assumption that chronic low back pain leads to deconditioning, physical training programs are widely used as a treatment. A total of 70 patients with chronic low back pain and 70 healthy asymptomatic subjects completed questionnaires regarding demographics and performed a graded maximal exercise test until exhaustion on a cycle ergometer. The maximal aerobic power was measured by indirect calorimetry. Heart rate, respiratory exchange ratio and blood lactate levels were also measured. The test was considered maximal when VO₂max achievement criteria were obtained. VO₂max values were compared among groups. The absolute and normalized for weight values of VO₂max measured in patients with chronic low back pain were significantly lower than that of the control group. Independent comparison between men and women showed that absolute values of VO₂max are also significantly lower in men and women with chronic low back pain. Women reached absolute and normalized for weight VO₂max values significantly lower than those of men, both in chronic low back pain and control group. In conclusion, chronic low back pain patients, especially women, seem to have a reduced aerobic capacity compared to healthy asymptomatic subjects.     

Interventions for reducing hospital-associated deconditioning: A systematic review and meta-analysis

PurposeTo determine the effectiveness of hospital-based interventions designed to reduce Hospital-Associated Deconditioning (HAD) for people in inpatient hospital settings.Materials & methodsSystematic literature search of published and unpublished databases was conducted from (inception to 01 June 2020). Randomised and non-randomised controlled trials investigating the effectiveness of enhanced inpatient programmes aimed to reduce HAD in adults admitted to a hospital ward were included. Evidence was appraised using the Cochrane Risk of Bias tool and outcomes evaluated against the GRADE criteria. Where appropriate, data were pooled in meta-analyses and presented as risk difference (RD) or standardised mean difference with 95 % confidence intervals (CI).ResultsSeven studies recruiting 12,597 participants (7864 enhanced programmes; 4349 usual care) were included. There was low-quality evidence for reduced risk of decline in physical performance for those in the enhanced programmes compared to usual care (RD: −0.04; 95 % CI: −0.08 to −0.01; N = 2085). There was low- or very-low quality evidence reporting no benefit of enhanced programmes for mobility on discharge, length of hospital stay, hospital readmission, and mortality within the first three-months post-admission (p > 0.05). There was low-quality evidence that nursing home placement and mortality at 12-months was superior through enhanced inpatient programmes compared to usual care.ConclusionEnhanced inpatient programmes targeted at HAD may offer benefit over usual care for some outcomes. There remain uncertainty in relation to how applicable the findings are to non-North American countries, which elements of an enhanced programme are most important to reduce HAD, and longer-term sequelae.     

Insights from an early-stage development mixed methods study on arts-based interventions for older adults following hospitalisation

BackgroundA period of hospitalisation can have negative consequences on physical function and autonomy for older adults, including functional decline, dependency and reduced quality of life. Older adults favour activity that focuses on social connectedness, fun and achievable skills.ObjectiveThe primary aim of this early-stage development mixed methods study was to determine the feasibility and acceptability of a randomised crossover trial design and two arts-based interventions tailored for older adults recently discharged from hospital.Materials and methodsCommunity-dwelling adults, aged 65 years and older, who reported reduced mobility and less than six weeks post discharge from hospital were invited to participate in the study. Two sites were randomised to either a four-week dance or music therapy intervention, followed by a four-week washout and subsequently to the alternate intervention. Participants and stakeholders were interviewed to share their views and perspectives of the study design and interventions developed.ResultsThe arts-based interventions were acceptable and safe for participants. Randomisation was completed per protocol and no implementation issues were identified. The outcome measures used were acceptable and feasible for this group of patients and did not lead to fatigue or excessive assessment time. Participants were positive about their experience of the programme.ConclusionsThis early development study provides a precursor and several imperative learning points to guide and inform future research in the area. Difficulties in recruitment and attrition were in part due to the barriers encountered when recruiting an incident cohort of vulnerable individuals post hospitalisation.     

Exercise thermoregulation after 6 h of chair rest, 6° head-down bed-rest,and water immersion deconditioning in men

The purpose was to investigate the mechanism for the excessive exercise hyperthermia following deconditioning (reduction of physical fitness). Rectal (T _re) and mean skin ( ) temperatures and thermoregulatory responses were measured in six men [mean (SD) age, 32 (6) years; mass, 78.26 (5.80) kg; surface area, 1.95 (0.11)m²; maximum oxygen uptake ( ), 48 (6) ml·min^–1·kg^–1; whilst supine in air at dry bulb temperature 23.2 (0.6)°C, relative humidity 31.1 (11.1)% and air speed 5.6 (0.1) m·min^–1] during 70 min of leg cycle exercise [51 (4)% ] in ambulatory control (AC), or following 6 h of chair rest (CR), 6° head-down bed rest (BR), and 20° (WI20) and 80° (WI80) foot-down water immersion [water temperature, 35.0 (0.1)°C]. Compared with the AC exercise T _re [mean (SD) 0.77 (0.13)°C], T _re after CR was 0.83 (0.08)°C (NS), after BR 0.92 (0.13)°C (^*P<0.05), after WI80 0.96 (0.13)°C^*, and after WI20 1.03 (0.09)°C^*. All responded similarly to exercise: they decreased (NS) by 0.5–0.7°C in minutes 4–8 and equilibrated at +0.1 to +0.5°C at 60–70. Skin heat conductance was not different among the five conditions (range = 147–159 kJ·m^–2·h^–1·°C^–1). Results from an intercorrelation matrix suggested that total body sweat rate was more closely related toT _re at 70 min (T _re70) than limb sweat rate or blood flow. Only 36% of the variability inT _re70 could be accounted for by total sweating, and less than 10% from total body dehydration. It would appear that multiple factors are involved which may include change in sensitivity of thermo- and osmoreceptors.     

The weighty issue of obesity in paediatric respiratory medicine

Some have observed that developed world is fat and getting fatter. This is even extending into the developing world, and it is important to appreciate that the consequences of childhood obesity last into adulthood and are associated with premature death. From the paediatric respiratory perspective, the deposition of excess adipose tissue in the thoraco-abdominal region begins early in life and is believed to alter diaphragm mobility and chest wall expansion, reduce lung compliance, and result in a rapid shallow breathing pattern with an increased work of breathing and reduction in maximum ventilatory capacity. This results in respiratory symptoms of exertional dyspnoea related to deconditioning which may present as exercise limitation, leading to confusion with common lung diseases such as asthma. The manifestations of the increasingly prevalent problems of overweight and obesity in young people and their interaction with common conditions of asthma and obstructive sleep apnoea will be discussed.     

Ventilatory threshold may be a more specific measure of aerobic capacity than peak oxygen consumption rate in persons with stroke

Background: After stroke, aerobic deconditioning can have a profound impact on daily activities. This is usually measured by the peak oxygen consumption rate achieved during exercise testing (VO2-peak). However, VO2-peak may be distorted by motor function. The oxygen uptake efficiency slope (OUES) and VO2 at the ventilatory threshold (VO2-VT) could more specifically assess aerobic capacity after stroke, but this has not been tested.

Objectives: To assess the differential influence of motor function on three measures of aerobic capacity (VO2-peak, OUES, and VO2-VT) and to evaluate the inter-rater reliability of VO2-VT determination post-stroke.

Methods: Among 59 persons with chronic stroke, cross-sectional correlations with motor function (comfortable gait speed [CGS] and lower extremity Fugl-Meyer [LEFM]) were compared between the different aerobic capacity measures, after adjustment for covariates, in order to isolate any distorting effect of motor function. Reliability of VO2-VT determination between three raters was assessed with intra-class correlation (ICC).

Results: CGS was moderately correlated with VO2-peak (r = 0.52, p < 0.0001) and weakly correlated with OUES (r = 0.41, p = 0.002) and VO2-VT (r = 0.37, p = 0.01). LEFM was weakly correlated with VO2-peak (r = 0.26, p = 0.055) and very weakly correlated with OUES (r = 0.19, p = 0.17) and VO2-VT (r = 0.14, p = 0.31). Compared to VO2-peak, VO2-VT was significantly less correlated with CGS (r difference = ?0.16, p = 0.02). Inter-rater reliability of VO2-VT determination was high (ICC: 0.93, 95% CI: 0.89–0.96).

Conclusions: Motor dysfunction appears to artificially lower measured aerobic capacity. VO2-VT seemed to be less distorted than VO2-peak and had good inter-rater reliability, so it may provide more specific assessment of aerobic capacity post-stroke.     

Lumbar surgery in work-related chronic low back pain: can a continuum of care enhance outcomes?

Background contextSystematic reviews of lumbar fusion outcomes in purely workers' compensation (WC) patient populations have indicated mixed results for efficacy. Recent studies on lumbar fusions in the WC setting have reported return-to-work rates of 26% to 36%, reoperation rates of 22% to 27%, and high rates of persistent opioid use 2 years after surgery. Other types of lumbar surgery in WC populations are also acknowledged to have poorer outcomes than in non-WC. The possibility of improving outcomes by employing a biopsychosocial model with a continuum of care, including postoperative functional restoration in this “at risk” population, has been suggested as a possible solution.PurposeTo compare objective socioeconomic and patient-reported outcomes for WC patients with different lumbar surgeries followed by functional restoration, relative to matched comparison patients without surgery.Study design/settingA prospective cohort study of chronic disabling occupational lumbar disorder (CDOLD) patients with WC claims treated in an interdisciplinary functional restoration program.Patient sampleA consecutive cohort of 564 patients with prerehabilitation surgery completed a functional restoration and was divided into groups based on surgery type: lumbar fusion (F group, N=331) and nonfusion lumbar spine surgery (NF group, N=233). An unoperated comparison group was matched for length of disability (U group, N=349).Outcome measuresValidated patient-reported measures of pain, disability, and depression were administered pre- and postrehabilitation. Socioeconomic outcomes were collected via a structured 1-year “after” interview.MethodsAll patients completed an intensive, medically supervised functional restoration program combining quantitatively directed exercise progression with a multimodal disability management approach. The writing of this article was supported in part by National Institutes of Health Grant 1K05-MH-71892; no conflicts of interest are noted among the authors.ResultsThe F group had a longer length of disability compared with the NF and U groups (M=31.6, 21.7, and 25.9 months, respectively, p<.001). There were relatively few statistically significant differences for any socioeconomically relevant outcome among groups, with virtually identical postrehabilitation return-to-work (F=81%, NF=84%, U=85%, p=.409). The groups differed significantly after surgery on diagnosis of major depressive disorder and opioid dependence disorder as well as patient-reported depressive symptoms and pain intensity prerehabilitation. However, no significant differences in patient-reported outcomes were found postrehabilitation. Prerehabilitation opioid dependence disorder significantly predicted lower rates of work return and work retention as well as higher rates of treatment-seeking behavior. Higher levels of prerehabilitation perceived disability and depressive symptoms were significant risk factors for poorer work return and retention outcomes.ConclusionsLumbar surgery in the WC system (particularly lumbar fusion) have the potential achieve positive outcomes that are comparable to CDOLD patients treated nonoperatively. This study suggests that surgeons have the opportunity to improve lumbar surgery outcomes in the WC system, even for complex fusion CDOLD patients with multiple prior operations, if they control postoperative opioid dependence and prevent an excessive length of disability. Through early referral of patients (who fail to respond to usual postoperative care) to interdisciplinary rehabilitation, the surgeon determining this continuum of care may accelerate recovery and achieve socioeconomic outcomes of relevance to the patient and WC jurisdiction through the combination of surgery and postoperative rehabilitation.