Vascular Responses following Light Therapy: A Pilot Study with Healthy Volunteers

(1) Background: Studies have reported the effectiveness of light therapy in various medical conditions. Our pilot study aimed to assess the effect of Maharishi light therapy (MLT) on physiological parameters, such as the heart rate (HR), HR variability (HRV), blood pressure (BP), BP variability (BPV), and the retinal microvasculature of healthy participants; (2) Methodology: Thirty (14 males and 16 females) healthy, non-smoking participants between 23 and 71 years old (46 ± 18 years) were included in this randomized crossover study. Each participant was tested with a placebo (using LED light) and gem lights, 24 h apart. Hemodynamic parameters were recorded during the session, and 24 h heart rate and BP levels were assessed via mobile devices. Retinal vascular responses were captured with fundus images and the subsequent analysis of retinal vessel widths. A linear model, using repeated measures ANOVA, was used to compare the responses across the sexes and to assess the effect of the MLT; (3) Results: Changes in the central retinal artery equivalent (CRAE) (p < 0.001) and central retinal vein equivalent (CRVE) (p = 0.002) parameters were observed. CRAE and CRVE decreased under MLT and increased under the placebo condition from before to after. However, the baseline values of the participants already differed significantly before the application of any therapy, and the variation in the retinal vessel diameters was already large in the baseline measurements. This suggests that the observed effect results may only reflect naturally occurring fluctuations in the microcirculation and not the effect of MLT. Furthermore, no significant effects were observed in any other investigated parameters; (4) Conclusion: Our study with healthy participants finds significant changes in retinal parameters, but the biological variation in the baseline measurements was large to begin with. This suggests that the observed effect results only reflect naturally occurring fluctuations in the microcirculation and not the effect of MLT. However, in the future, larger studies in which MLT is applied for longer periods and/or in patients with different diseases could discover the physiological impacts of this type of therapy.publishedVersio

Relationship between High Blood Pressure and Microalbuminuria in Children Aged 6–9 Years in a South African Population

Though the association between high blood pressure and microalbuminuria is well established in adults, there is a paucity of information on microalbuminuria in children. This study investigated the relationship between high blood pressure and microalbuminuria in 6&ndash;9-year-old children. A cross-sectional study, which included 306 primary school children of age 6&ndash;9 years old from urban areas (n = 154) and rural areas (n = 152) of the Eastern Cape Province of South Africa, was conducted. Participants&rsquo; anthropometric data were determined and systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured and converted to BP percentiles for age, sex and height. Creatinine and albumin concentrations were assayed in early morning midstream urine and the albumin to creatinine ratio (ACR) was calculated. There was a 42.8% prevalence of elevated blood pressure/high blood pressure (E-BP/H-BP) and a 10.1% prevalence of microalbuminuria. Among the 131 children with E-BP/H-BP, 17 had elevated ACR with a prevalence of 13.95%. SBP and HR increased with increasing range of ACR and, furthermore, SBP was significantly (p &lt; 0.05) higher in children with moderately and severely increased ACR. SBP was associated with ACR and increased SBP predicted microalbuminuria (R2 = 0.42, adj R2 = 0.039, B: 0.120, p = &lt; 0.05). In conclusion, microalbuminuria was present in 6&ndash;9-year-old South African children of African Ancestry and a weak association was observed with SBP in children