A 16-Week Aerobic Exercise Intervention Does Not Affect Hippocampal Volume and Cortical Thickness in Mild to Moderate Alzheimer's Disease

Introduction: Brain imaging studies in healthy elderly subjects suggest a positive effect of aerobic exercise on both brain structure and function, while the effects of aerobic exercise in Alzheimer's Disease (AD) has been scarcely investigated. Methods: In a single-blinded randomized MRI study, we assessed the effects of an aerobic exercise intervention on brain volume as measured by magnetic resonance imaging (MRI) and its correlation to cognitive functioning in patients with AD. The study was a sub-study of a larger randomized controlled trial (ADEX study). Forty-one patients were assigned to a control or exercise group. The exercise group performed 60-min of aerobic exercise three times per week for 16 weeks. All participants underwent whole-brain MRI at 3 Tesla and cognitive assessment at baseline and after 16 weeks. Attendance and intensity were monitored providing a total exercise load. Changes in regional brain volumes and cortical thickness were analyzed using Freesurfer software. Results: There was no effect of the type of intervention on MRI-derived brain volumes. In the entire group with and without training, Exercise load showed a positive correlation with changes in volume in the hippocampus, as well as frontal cortical thickness. Volume changes in frontal cortical thickness correlated with changes in measures of mental speed and attention and exercise load in the exercise group. Conclusion: We did not find evidence to support an effect of 16 weeks of aerobic exercise on brain volume changes in patients with AD. Longer intervention periods may be needed to affect brain structure as measured with volumetric MRI. Clinical Trial registration: ClinicalTrials.gov Identifier: NCT01681602, registered September 10th, 2012 (Retrospectively registered).</p

A 16-Week Aerobic Exercise Intervention Does Not Affect Hippocampal Volume and Cortical Thickness in Mild to Moderate Alzheimer’s Disease

Introduction: Brain imaging studies in healthy elderly subjects suggest a positive effect of aerobic exercise on both brain structure and function, while the effects of aerobic exercise in Alzheimer’s Disease (AD) has been scarcely investigated.Methods: In a single-blinded randomized MRI study, we assessed the effects of an aerobic exercise intervention on brain volume as measured by magnetic resonance imaging (MRI) and its correlation to cognitive functioning in patients with AD. The study was a sub-study of a larger randomized controlled trial (ADEX study). Forty-one patients were assigned to a control or exercise group. The exercise group performed 60-min of aerobic exercise three times per week for 16 weeks. All participants underwent whole-brain MRI at 3 Tesla and cognitive assessment at baseline and after 16 weeks. Attendance and intensity were monitored providing a total exercise load. Changes in regional brain volumes and cortical thickness were analyzed using Freesurfer software.Results: There was no effect of the type of intervention on MRI-derived brain volumes. In the entire group with and without training, Exercise load showed a positive correlation with changes in volume in the hippocampus, as well as frontal cortical thickness. Volume changes in frontal cortical thickness correlated with changes in measures of mental speed and attention and exercise load in the exercise group.Conclusion: We did not find evidence to support an effect of 16 weeks of aerobic exercise on brain volume changes in patients with AD. Longer intervention periods may be needed to affect brain structure as measured with volumetric MRI.Clinical Trial registration:ClinicalTrials.gov Identifier: NCT01681602, registered September 10th, 2012 (Retrospectively registered)

Is There Migration-Related Inequity in Access to or in the Utilisation of Health Care in Germany?

This paper analyses immigrants' access to health care and utilisation of health care services in Germany. Thereby, it is investigated if there is inequity in access to or in the utilisation of health care services due to a lack of language skills or due to a lack of information about the health care system (approximated by years since migration)among first- and secondgeneration immigrants. The data used are drawn from eleven waves of the SOEP (1995-2006). With regard to the probability to contacta physician (as a proxy for access), German language skills are found to have no significant influence for all groups of immigrants. The hypothesis of inequity in access to health care due to access barriers caused by a lack of German language skills is therefore not supported by the data. However, mother tongue language skillsseem to be important for the contact probability of the first- and secondgeneration: Having only good or poor mother tongue language skills reduces the probability of a doctor contact. The effect is found to be significant for first- and second-generation men. For the frequency of doctor visits (utilisation), poor German language skills are found to exert a significant influence: Those reporting poor language skills have a lower expected number of doctor visits. The effect is found to be significant for first-generation men and for secondgeneration men and women. Hence, there seems to be inequity in health care utilisation due to a lack of German language skills. With the exception of first-generation men - where it is found that poor mother tongue language skills reduce the expected number of doctor visits significantly, no significant effect is found for mother tongue language skills. With regard to the duration of residence, the results indicate that years since migration have an impact on the contact decision of first-generation immigrant women, whereby a significant positive influence is found. Hence, missing knowledge about the health care system could create additional access barriers and yield inequity in access to health care in the group of firstgeneration women. The duration of residence seems to have no influence on the frequency decision