Physical fitness in depressive patients and impact of illness course and disability

BACKGROUND

There is a large and increasing body of evidence that physical exercise, such as endurance training, exerts antidepressant effects in psychiatric disorders. However, compliance rates are rather low due to reduced energy and lack of motivation. Another important reason may be low baseline fitness leading to overstrain when participating in a training program. The aim of the study was to evaluate the physical fitness of depressive patients compared to healthy controls by a standardized assessment.

METHODS

51 hospitalized depressive patients were investigated by a standardized physical fitness assessment on a bicycle ergometer including measurement of maximum workload (pmax), heart rate, lactate concentration, workload at first lactate elevation (pLT), individual anaerobic threshold (IAT) and workload at IAT (pIAT). They were compared to 51 healthy controls matched for age, sex and body mass index.

RESULTS

p(max), p(LT) and p(IAT) were markedly reduced in depressive patients compared to healthy controls (p<0.001). Lactate increase was faster and steeper in depressed patients, albeit differences never reached significant levels. There was a significant negative correlation between the length of disability and poor performance parameters but no significant correlation with other illness variables.

LIMITATIONS

The study was not prospective and no study protocol was applied.

CONCLUSION

This study demonstrates a marked reduction of physical fitness in depressive patients which cannot be explained by differences of body mass index or age. When designing therapeutic exercise programs for depressive patients evaluation of baseline training level is recommendable because many patients might overstrain themselves because of strongly reduced baseline fitness.

Frontostriatal activation in patients with obsessive-compulsive disorder before and after cognitive behavioral therapy

BACKGROUND

Cognitive behavioral therapy (CBT) with exposure and response prevention (ERP) is the psychotherapeutic treatment of choice for obsessive-compulsive disorder (OCD). However, little is known about the impact of CBT on frontostriatal dysfunctioning, known to be the neuronal correlate of OCD.

METHOD

A probabilistic reversal learning (RL) task probing adaptive strategy switching capabilities was used in 10 unmedicated patients with OCD and 10 healthy controls during an event-related functional magnetic resonance imaging (fMRI) experiment. Patients were scanned before and after intensive CBT, controls twice at comparable intervals.

RESULTS

Strategy change within the RL task involved activity in a broad frontal network in patients and controls. No significant differences between the groups or in group by time interactions were detected in a whole-brain analysis corrected for multiple comparisons. However, a reanalysis with a more lenient threshold revealed decreased responsiveness of the orbitofrontal cortex and right putamen during strategy change before treatment in patients compared with healthy subjects. A group by time effect was found in the caudate nucleus, demonstrating increased activity for patients over the course of time. Patients with greater clinical improvement, reflected by greater reductions in Yale-Brown Obsessive Compulsive Scale (YBOCS) scores, showed more stable activation in the pallidum.

CONCLUSIONS

Although these findings are preliminary and need to be replicated in larger samples, they indicate a possible influence of psychotherapy on brain activity in core regions that have been shown to be directly involved both in acquisition of behavioral rules and stereotypes and in the pathophysiology of OCD, the caudate nucleus and the pallidum.