Effectiveness of the Coordinated Return to Work model after orthopaedic surgery for lumbar discectomy and hip and knee arthroplasty: a register-based study.

OBJECTIVES: This study examined the effectiveness of an individualised Coordinated Return to Work (CRtW) model on the length of the return to work (RTW) period compared with a standard prescription of 2-3 months RTW during recovery after lumbar discectomy and hip and knee arthroplasty among Finnish working-age population. METHODS: Cohorts on patients aged 18-65 years old with lumbar discectomy or hip or knee arthroplasty were extracted from the electronic health records of eight Finnish hospital districts in 2015-2021 and compiled with retirement and sickness benefits. The overall effect of the CRtW model on the average RTW period was calculated as a weighted average of area-specific mean differences in RTW periods between 1 year before and 1 year after the implementation. Longer-term effects of the model were examined with an interrupted time series design estimated with a segmented regression model. RESULTS: During the first year of the CRtW model, the average RTW period shortened by 9.1 days (95% CI 4.1 to 14.1) for hip arthroplasty and 14.4 days (95% CI 7.5 to 21.3) for knee arthroplasty. The observed differences were sustained over longer follow-up times. For lumbar discectomy, the first-year decrease was not statistically significant, but the average RTW had shortened by 36.2 days (95% CI 33.8 to 38.5) after 4.5 years. CONCLUSIONS: The CRtW model shortened average RTW periods among working-age people during the recovery period. Further research with larger samples and longer follow-up times is needed to ensure the effectiveness of the model as a part of the Finnish healthcare system.

Resting heart rate predicts cardiac autonomic modulation during passive head-up tilt in subjects without cardiovascular diseases.

Background Resting heart rate (HR) and its variability (HRV) reflects the cardiac sympathovagal balance that is stimulated by head-up tilting. HRV is influenced by the level of HR, but how much HRV offers additional information about cardiac autonomic tone than HR alone remains unresolved. We examined the relation of resting HR with HRV during head-up tilt. Methods. Hemodynamics of 569 subjects without known cardiovascular diseases and medications with direct cardiovascular effects were recorded using whole-body impedance cardiography, radial pulse wave analysis, and electrocardiography-based HRV analysis during passive head-up tilt. Results. Higher low frequency to the high-frequency ratio (LF/HF) of HRV (reflecting sympathovagal balance) was associated with higher HR in supine (p < .05, both linear regression analysis and variance analysis comparing HR tertiles) and upright postures (p < .001, linear regression analysis). The association of HR with HRV during tilt-testing remained significant when the HR dependence of HRV was mathematically weakened by dividing the HRV power spectra with the fourth power of the average RR-interval. Conclusion. Higher resting HR is related to higher LF/HF both supine and upright, reflecting elevated sympathetic influence on cardiac autonomic modulation. Lower resting HR is associated with lower resting LF/HF, while the differences in LF/HF between the HR tertiles were minor during head-up tilt, suggesting a greater change in cardiac sympathovagal balance in response to upright posture in those with lowest resting HR. Altogether, resting HR well predicts HRV levels during head-up tilt.Trial registration: Clinicaltrialsregister.eu 2006-002065-39, first registered 5 May 2006. ClinicalTrials.gov NCT01742702, first registered 5 December 2012.

Changes in hemodynamics associated with metabolic syndrome are more pronounced in women than in men.

The increase in cardiovascular risk associated with metabolic syndrome (MS) seems higher in women than in men. We examined hemodynamics during head-up tilt in 252 men and 250 women without atherosclerosis, diabetes, or antihypertensive medication, mean age 48 years, using whole-body impedance cardiography and radial pulse wave analysis. MS was defined according to Alberti et al. 2009. Men and women with MS presented with corresponding elevations of systolic and diastolic blood pressure (10-14%, p ≤ 0.001) versus controls. Supine pulse wave velocity (16-17%, p < 0.001) and systemic vascular resistance (7-9%, p ≤ 0.026), and upright cardiac output (6-11%, p ≤ 0.008) were higher in both MS groups than controls. Elevation of supine aortic characteristic impedance was higher in women than in men with MS (16% vs. 8%, p = 0.026), and in contrast to men, no upright impedance reduction was observed in women. When upright, women but not men with MS showed faster return of reflected pressure wave (p = 0.036), and smaller decrease in left cardiac work (p = 0.035) versus controls. The faster upright return of reflected pressure, lower upright decrease in left cardiac work, and higher elevation of aortic characteristic impedance may contribute to the greater increase in MS-related cardiovascular risk in women than in men.

Metabolic syndrome is associated with decreased heart rate variability in a sex-dependent manner: a comparison between 252 men and 249 women.

Impaired heart rate variability (HRV) is associated with increased risk of cardiovascular disease, but evidence regarding alterations of HRV in metabolic syndrome (MetS) remains elusive. In order to examine HRV in MetS, we subjected 501 volunteers without atherosclerosis, diabetes or antihypertensive medication, mean age 48 years, to passive head-up tilt. The subjects were divided to control men (n = 131), men with MetS (n = 121), control women (n = 191) and women with MetS (n = 58) according to the criteria by Alberti et al. (Circulation, 2009, 120, 1640). In unadjusted analyses (i) men and women with MetS had lower total power and high-frequency (HF) power of HRV than controls whether supine or upright (P<0·05 for all). (ii) Supine low-frequency (LF) power of HRV was lower in men (P = 0·012) but not in women (P = 0·064) with MetS than in controls, while men and women with MetS had lower upright LF power of HRV than controls (P <0·01 for both). (iii) The LF:HF ratio did not differ between subjects with and without MetS. After adjustment for age, smoking habits, alcohol intake, height, heart rate and breathing frequency, only the differences in upright total power and HF power of HRV between women with MetS and control women remained significant (P<0·05). In conclusion, reduced total and HF power of HRV in the upright position may partially explain why the relative increase in cardiovascular risk associated with MetS is greater in women than in men. Additionally, the present results emphasize that the confounding factors must be carefully taken into consideration when evaluating HRV.

Salbutamol-induced Decrease in Augmentation Index is Related to the Parallel Increase in Heart Rate.

The change in augmentation index following salbutamol inhalation has been applied to evaluate endothelial function. We examined the contribution of salbutamol-induced increase in heart rate to the observed decrease in augmentation index. Haemodynamics were recorded using whole-body impedance cardiography and continuous pulse wave analysis from tonometric radial blood pressure. All subjects (n = 335, mean age 46, body mass index 26, 48% men) were without medications with cardiovascular influences. The effects of salbutamol inhalation (0.4 mg) versus the endothelium-independent agent nitroglycerin resoriblet (0.25 mg) were examined during passive head-up tilt, as the haemodynamic influences of these compounds depend on body position. Salbutamol decreased augmentation index by ~3-4% units in supine and upright positions. Although salbutamol moderately increased cardiac index (+4.5%) and decreased systemic vascular resistance (-8.5%), the significant haemodynamic explanatory factors for decreased augmentation index in multivariate analysis were increased supine heart rate, and increased upright heart rate and decreased ejection duration (p < 0.001 for all, r2  = 0.36-0.37). Sublingual nitroglycerin decreased supine and upright augmentation index by ~15% units and ~23% units, respectively. The haemodynamic explanatory factors for these changes in multivariate analysis were increased heart rate, reduced ejection duration and reduced systemic vascular resistance (p ≤ 0.021 for all, r2  = 0.22-0.34). In conclusion, the lowering influence of salbutamol on augmentation index may be largely explained by increased heart rate, suggesting that this effect may not predominantly reflect endothelial function.

Increased Cardiac Workload in the Upright Posture in Men: Noninvasive Hemodynamics in Men Versus Women.

BACKGROUND: Men and women differ in the risk of cardiovascular disease, but the underlying mechanisms are not completely understood. We examined possible sex-related differences in supine and upright cardiovascular regulation. METHODS AND RESULTS: Hemodynamics were recorded from 167 men and 167 women of matching age (≈45 years) and body mass index (≈26.5) during passive head-up tilt. None had diabetes mellitus or cardiovascular disease other than hypertension or used antihypertensive medication. Whole-body impedance cardiography, tonometric radial blood pressure, and heart rate variability were analyzed. Results were adjusted for height, smoking, alcohol intake, mean arterial pressure, plasma lipids, and glucose. Supine hemodynamic differences were minor: Men had lower heart rate (-4%) and higher stroke index (+7.5%) than women (P<0.05 for both). Upright systemic vascular resistance was lower (-10%), but stroke index (+15%), cardiac index (+16%), and left cardiac work were clearly higher (+20%) in men than in women (P<0.001 for all). Corresponding results were observed in a subgroup of men and postmenopausal women (n=76, aged >55 years). Heart rate variability analyses showed higher low:high frequency ratios in supine (P<0.001) and upright (P=0.003) positions in men. CONCLUSIONS: The foremost difference in cardiovascular regulation between sexes was higher upright hemodynamic workload for the heart in men, a finding not explained by known cardiovascular risk factors or hormonal differences before menopause. Heart rate variability analyses indicated higher sympathovagal balance in men regardless of body position. The deviations in upright hemodynamics could play a role in the differences in cardiovascular risk between men and women. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01742702.

Metabolic syndrome may be associated with increased arterial stiffness even in the absence of hypertension: a study in 84 cases and 82 controls.

OBJECTIVE: To evaluate the hemodynamic characteristics of metabolic syndrome (MetS) in the absence and presence of hypertension. MATERIALS/METHODS: Altogether 166 subjects without previously diagnosed cardiovascular disease, diabetes, or antihypertensive medication, were allocated to four groups: control, hypertension only, MetS without hypertension, and MetS with hypertension (mean age 44-46 years). Cut-point for hypertension was blood pressure ≥140/90 mmHg. Other criteria of MetS were as defined by Alberti et al. 2009. Hemodynamic variables were measured using whole-body impedance cardiography and pulse wave analysis. RESULTS: Pulse wave velocity was higher in hypertensive and normotensive subjects with MetS than controls (p<0.05), and in the hypertensive MetS group than subjects with hypertension only (p<0.05). Aortic pulse pressure was higher in the two hypertensive groups than the two normotensive groups (p<0.05). Systemic vascular resistance index was higher in the hypertensive than normotensive MetS group (p<0.05), and in the group with hypertension alone than in controls (p<0.05). Heart rate was higher in the hypertensive Mets group than in controls and subjects with hypertension only (p<0.05). Cardiac index did not differ, while stroke index was lower in both groups with MetS than groups without MetS. Augmentation pressure was higher in the hypertensive MetS group than in controls and normotensive MetS group (p<0.05). CONCLUSIONS: Pulse wave velocity, an acknowledged marker of arterial stiffness, was associated with MetS even in the absence of hypertension. This emphasizes the importance of the prevention and treatment of MetS.