Event-Related Potential Changes Following 12-week Yoga Practice in T2DM Patients: A Randomized Controlled Trial.

Introduction. Type 2 diabetes patients are more likely to experience cognitive decline (1.5%) and dementia (1.6%) than healthy individuals. Although cognitive impairment adversely affects Type 2 diabetes mellitus (T2DM) patients, it is the least addressed complication of T2DM patients. Objective. The present study attempts to examine the changes in cognitive performance of T2DM patients and the probable factors contributing to the changes following 12-week yoga practice. Methods. The current study is a parallel group randomized controlled trial that compared the outcomes of the participants randomized to a yoga group (YG) (n = 25) and to a wait-list control group (n = 29). The study assessed N200 and N450 event-related potential (ERP) components following the Stroop task, heart rate variability (HRV) and HbA1c before and after the intervention. Results. The mean amplitude of the N200 ERP component showed a significant group difference after the intervention, demonstrating an improved neural efficiency in the process of conflict monitoring and response inhibition. No differences were present for the N450 component. T2DM patients showed reduced heart rate and increased mean RR following yoga practice without any corresponding changes in other HRV parameters, demonstrating an overall improvement in cardiac activity. Along with that yoga practice also reduced HbA1c levels in T2DM patients, indicating improved glycemic control. Moreover, HbA1c levels were negatively correlated with reaction time after the intervention, indicating an impact of glycemic control on cognitive performance. Conclusion. The 12-week yoga practice improved cognitive performance by enhancing the processes of conflict monitoring and response inhibition. Further, improved cognitive performance postintervention was facilitated by improved glycemic control.

Cerebral Haemodynamic Changes in Type 2 Diabetes Mellitus Following a Three-Month Yoga Intervention: A Randomized Controlled Trial.

Background and purpose Cerebral haemodynamics and cognitive performance may be adversely affected in type 2 diabetes mellitus (T2DM). Previous studies reported reduced cerebral blood flow (CBF) and altered cerebrovascular reactivity (CVR) in T2DM. Yoga, an ancient holistic health approach, is known to be beneficial for T2DM. We hypothesized that yoga practice may alter CBF and the flow resistance in the middle cerebral artery (MCA) and improve cognition in T2DM. Our secondary objective was to explore the relationship between changes in cerebral haemodynamics and cognition in T2DM. Materials and methods Participants were randomly allotted into the yoga and control groups based on the eligibility criteria. One hour of yoga intervention specific to type 2 diabetes was provided to the yoga group for three months, while conventional treatment was provided to the control group. A transcranial Doppler was used to evaluate longitudinal changes in cerebral haemodynamics in MCA. A Corsi block tapping test was used to assess visio-spatial working memory. Results There were 75 participants recruited, of whom 38 participated in yoga and 37 participated in a control group. Both intention to treat and per protocol analysis showed significant results. At day 90, intention-to-treat analysis showed significant changes in CBF velocities (mean difference -10.85%, 95% CI (-13.26, -6.15), p<0.001), cerebral vasodilatory reserve (mean difference -0.23%, 95% CI (-0.43, -0.03), p=0.02) and cognition (mean difference -12.13%, 95% CI (-17.48, -6.78), p≤0.001). There was no between-group effect. Also, the correlation between the CBF and cognition did not show any significant results. Conclusion The three-month yoga intervention was associated with an improvement in cerebral hemodynamics. The study also revealed an improvement in visio-spatial working memory among patients with T2DM. The study did not show any correlation between the improvement in cerebral haemodynamics and working memory. We recommend larger and longer studies on yoga intervention for T2DM patients to evaluate whether such benefits are sustained and improve their quality of life.

Prefrontal oxygenation and working memory in patients with type 2 diabetes mellitus following integrated yoga: a randomized controlled trial.

AIMS: Type 2 diabetes mellitus (T2DM) alters brain functional and structural connectivity leading to cognitive dysfunction. This study examined the effect of a 12-week yoga intervention on prefrontal cortex (PFC) oxygenation and working memory in patients with T2DM. METHODS: Fifty participants were randomized into yoga and waitlist control groups. The yoga protocol specific to T2DM was followed. The pre- (day 1), mid- (6 weeks) and post-intervention (12 weeks) assessments included measurement of PFC oxygenation while performing working memory tasks (n-back) using functional near-infrared spectroscopy. RESULTS: Following a 12-week intervention, the yoga group showed improved performance in working memory [accuracy (geometric mean difference of 3.15%, 95% CI [2.33,3.96], p = 0.001) and reaction time (mean difference of 100.8 milliseconds,95% CI [- 166.6, - 35.1], p = 0.002] in the high task load (2-back) associated with higher oxygenation in dorsolateral PFC (ß coefficient mean difference of 95.6, 95% CI [0.23,191], p = 0.049) and ventrolateral PFC (ß coefficient mean difference of 53.4, 95% CI [7.8,98.9], p = 0.018) regions. Higher oxygenation in dorsolateral PFC during 2-back task was positively correlated with accuracy (r(23) = 0.65, p < 0.001) and negatively correlated with reaction time (r(23) = - 0.47,p = 0.017). CONCLUSION: Integrated yoga practice may improve working memory performance associated with higher PFC oxygenation in patients with T2DM. As 12 weeks of yoga intervention improved working memory performance, the regular practice of yoga may have the potential to prevent decline of cognitive functions in clinical conditions.

Transcranial Doppler studies in Type 2 diabetes mellitus: A systematic review.

BACKGROUND: Type II Diabetes mellitus (T2DM) patients are at the risk of developing cerebrovascular diseases, often contributed by altered cerebral haemodynamics. We present a systematic review of studies on cerebral haemodynamics assessment using transcranial Doppler (TCD) in T2DM. REVIEW METHOD: A systematic review of the published articles in the English language between 1991 to 2021. DATA SOURCES: Articles were retrieved via Pubmed and Cochrane library. We included Cross-sectional, prospective, retrospective, randomized controlled, and cross-over studies for this review. RESULTS: A total of 25 articles met the inclusion criteria, which provided data for 3212 patients. CONCLUSION: Cerebral autoregulation is often impaired among patients with T2DM. The risk increased with the duration of T2DM, related complications and presence of comorbidities.