Showing papers by "Ralf Schwarzer published in 2023"

Enhancing physical activity and reducing symptoms of patients with osteoarthritis of the knee: a randomized controlled trial of the PrevOP-Psychological Adherence Program

Abstract: This primary analysis evaluated the "PREVenting the impairment of primary Osteoarthritis by high-impact long-term Physical exercise regimen-Psychological Adherence Program" (PrevOP-PAP), designed to support patients with osteoarthritis of the knee (OAK) to engage in regular moderate-to-vigorous physical activity (MVPA) to reduce OAK symptoms (WOMAC scores). Theory-based on the health action process approach (HAPA), the intervention targeted volitional precursors of MVPA change: action and coping planning, maintenance and recovery self-efficacy, action control, and social network formation. We hypothesized that compared to an active control condition, increases in MVPA at the end of the 12-month intervention would translate into lower WOMAC scores at 24 months in the intervention condition.Participants with radiographically verified moderate OAK (N = 241; 62.66% female; M(SD) = 65.60(7.61) years) were randomly assigned to the intervention (51%) or the active control condition. WOMAC scores (24 months) were the primary -, accelerometer-assessed MVPA (12 months) the key secondary outcomes. The PrevOP-PAP was a 12-month intervention with computer-assisted face-to-face and phone-based sessions designed to increase HAPA-proposed volitional precursors of MVPA change (up to 24 months; secondary outcomes). Intent-to-treat analyses included multiple regression and manifest path models.MVPA (12 months) did not mediate effects of the PrevOP-PAP on WOMAC scores (24 months). Compared to the active control condition, WOMAC scores (24 months) were lower in the intervention condition, but this effect did not remain stable in sensitivity analyses (b(SE) = -8.41(4.66), 95%-CI [-17.53; 0.71]). However, exploratory analyses revealed significantly stronger reductions in WOMAC-pain (24 months) in the intervention condition (b(SE) = -2.99(1.18), 95%-CI [-5.36; -0.63]). Groups did not differ in MVPA at 12 months (b(SE) = -3.78(3.42), 95%-CI [-10.80; 2.58]). Of the proposed precursors of MVPA change, action planning was higher in the intervention than in the control condition (24 months; b(SE) = 0.64(0.26), 95%-CI [0.14; 1.15]).Compared to an active control condition, the PrevOP-PAP did not produce reliable effects on WOMAC scores and none on preceding MVPA. Of the HAPA-proposed volitional precursors, only action planning was sustainably increased. Future interventions should use m-health applications to digitally support long-term changes in proposed volitional precursors of MVPA change.German Clinical Trials Register; https://drks.de/search/de/trial/DRKS00009677 ; also available at http://apps.who.int/trialsearch/ ; registration number: DRKS00009677; date of registration: 26/01/2016.

Eating healthy under work stress: A gene stress interaction model.

Abstract: OBJECTIVE Some employees tend to eat less healthy food when under work stress, while others tend to maintain a healthy diet. The factors underlying these different dietary choices are not yet clear. Individual differences in people's reactions to environmental stress may help explain this phenomenon. This study proposed a Gene × Stress interaction model of dietary choice, suggesting that different dietary choices under stress may be related to DRD2 genes, which moderate the reward circuitry and have been associated with habitual use of alcohol, obesity, and eating behaviors. METHOD 12,269 employees completed genotyping of their saliva samples and questionnaires on work stress, healthy dietary intentions, and healthy dietary behaviors. Nonlinear multiple regressions were used to test the hypothesized interaction of DRD2 genes and work stress on healthy dietary intentions and healthy dietary behaviors. RESULTS Individuals with higher work stress reported lower healthy dietary intentions, whereas healthy dietary behaviors exhibited an inverted U shape. DRD2 genes significantly moderated this relationship, and the above relationship was only detected among C allele carriers, whereas for the AA genotype, work stress was not associated with healthy dietary intentions or behaviors. CONCLUSIONS Healthy dietary intentions and healthy dietary behaviors showed different patterns of association with work stress. The DRD2 genes helped explain the individual differences in dietary choice under work stress. (PsycInfo Database Record (c) 2023 APA, all rights reserved).