Reliability and clinical correlates of the Astrand–Rhyming sub-maximal exercise test in patients with schizophrenia or schizoaffective disorder

Abstract

Reliability and clinical correlates of the Astrand-Rhyming sub-maximal exercise test in patients with schizophrenia or schizoaffective disorder, Psychiatry Research, http://dx.doi.org/10.1016/j.psychres. 2014.08.049 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractCardiovascular fitness is reduced in people with schizophrenia and is related to an increased morbidity and mortality. There is mounting interest in the accurate measurement of cardiovascular fitness in schizophrenia, yet existing measures used in the general population have not been tested on validity and reliability in this high-risk group. Therefore, we examined the reproducibility and feasibility of the Astrand-Rhyming sub-maximal exercise test in patients with schizophrenia or schizoaffective disorder. Secondary aims were to assess minimal detectable changes, practice effects and the presence of clinical symptoms that are associated with cardio-respiratory fitness (expressed as estimated oxygen uptake). From 47 patients with schizophrenia or schizoaffective disorder two trials of the Astrand-Rhyming test, administered within three days, were analysed. The intraclass correlation coefficient for the estimated oxygen uptake between the two tests was 0.92 (95% confidence interval: 0.85 to 0.95). The minimal detectable change was 6.5mlO 2 /min/kg. No practice effect could be detected. A backward regression analysis demonstrated that illness duration, negative symptoms and level of physical activity explained 63.0% of the variance in estimated oxygen uptake. The current study demonstrates that the Astrand-Rhyming test can be recommended for evaluating the aerobic fitness in patients with schizophrenia or schizoaffective disorder.

Twelve-week physical exercise does not have a long-lasting effect on kynurenines in plasma of depressed patients

“…These changes indicate an important improvement in metabolic and cardiovascular health of the patients and are in line with other studies published on 12-week intervention programs 19,20. Although it has not been tested in depressed patients before, data on patients with schizophrenia indicate that familiarization effects are minimal 21. The increase in fitness, however, was not correlated in any way to changes in kynurenine ( r =−0.11, P =0.32), KYNA ( r =−0.01, P =0.89) or the KYNA/kynurenine ratio ( r =0.11, P =0.44; Figure 1E).…”

Metabolic syndrome and aerobic fitness in patients with first-episode schizophrenia, including a 1-year follow-up

“…Based on HR at a specific workload (Watt) the oxygen uptake (VO 2 max) was estimated using the Astrand-Rhyming sex-and age-sensitive nomogram. A recent study has proved The AastrandRhyming test as valid and applicable for patients with schizophrenia (Vancampfort et al, 2014).…”

Associations Between Metabolic and Aerobic Fitness Parameters in Patients With Schizophrenia

“…The Astrand-Rhyming protocol is a single-stage cycle ergometer test designed to elicit a steady-state HR for a 6-minute period. Recent research (Vancampfort et al, 2014a) has demonstrated that the Astrand-Rhyming test is a reliable and safe test to measure aerobic capacity of people with schizophrenia. The initial workload was selected from the Astrand test loading wattage table, pedaling speed remained constant (60 revolutions/minute), and HR was recorded at every minute interval.…”