The synergistic effect of vitamin D supplement and mindfulness training on pain severity, pain-related disability and neuropathy-specific quality of life dimensions in painful diabetic neuropathy: a randomized clinical trial with placebo-controlled

Psychologically based interventions for adults with chronic neuropathic pain: a scoping review

OBJECTIVE

As psychologically based interventions have been shown to have clinical utility for adults with chronic pain generally, a similar benefit might be expected in the management of chronic neuropathic pain (NeuP). However, to date, this has not been established, with existing systematic reviews on this topic being hampered by the scarcity of randomized controlled trials (RCTs). This review aimed to identify the type of psychologically based interventions studied for adults with chronic NeuP. It also aimed to assess whether there are enough RCTs to justify undertaking an updated systematic review.

METHODS

Seven databases and 2 clinical trial registries were searched for NeuP and psychologically based interventions from database inception to December 2021, and the search was updated in February 2023. The search was broadened by reviewing the reference list of included studies and contacting field experts. Predetermined study characteristics were extracted.

RESULTS

Of 4682 records screened, 33 articles (less than 1%) met the eligibility criteria. Four broad intervention approaches were observed, including cognitive-behavioral approaches (n = 16), mindfulness/meditation (n = 10), trauma-focused therapy (n = 4), and hypnosis (n = 3). Thirteen RCTs were identified, and of these, 9 retained 20 participants in each arm after treatment.

CONCLUSIONS

Cognitive-behavioral therapy was the most common therapeutic approach identified, whereas mindfulness/meditation was the most frequently used technique. Almost half to two-thirds of the studies reported significant improvements in pain, disability, or distress, which suggests that psychologically based interventions are potentially beneficial for adults with chronic NeuP. An updated systematic review seems warranted.

STUDY REGISTRATION

Open Science Framework (https://osf.io) (December 6, 2021; DOI: 10.17605/OSF.IO/WNSTM).

Meditation for the primary and secondary prevention of cardiovascular disease

BACKGROUND

Interventions incorporating meditation to address stress, anxiety, and depression, and improve self-management, are becoming popular for many health conditions. Stress is a risk factor for cardiovascular disease (CVD) and clusters with other modifiable behavioural risk factors, such as smoking. Meditation may therefore be a useful CVD prevention strategy.

OBJECTIVES

To determine the effectiveness of meditation, primarily mindfulness-based interventions (MBIs) and transcendental meditation (TM), for the primary and secondary prevention of CVD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases, and two trials registers on 14 November 2021, together with reference checking, citation searching, and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of 12 weeks or more in adults at high risk of CVD and those with established CVD. We explored four comparisons: MBIs versus active comparators (alternative interventions); MBIs versus non-active comparators (no intervention, wait list, usual care); TM versus active comparators; TM versus non-active comparators.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were CVD clinical events (e.g. cardiovascular mortality), blood pressure, measures of psychological distress and well-being, and adverse events. Secondary outcomes included other CVD risk factors (e.g. blood lipid levels), quality of life, and coping abilities. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 81 RCTs (6971 participants), with most studies at unclear risk of bias. MBIs versus active comparators (29 RCTs, 2883 participants) Systolic (SBP) and diastolic (DBP) blood pressure were reported in six trials (388 participants) where heterogeneity was considerable (SBP: MD -6.08 mmHg, 95% CI -12.79 to 0.63, I2 = 88%; DBP: MD -5.18 mmHg, 95% CI -10.65 to 0.29, I2 = 91%; both outcomes based on low-certainty evidence). There was little or no effect of MBIs on anxiety (SMD -0.06 units, 95% CI -0.25 to 0.13; I2 = 0%; 9 trials, 438 participants; moderate-certainty evidence), or depression (SMD 0.08 units, 95% CI -0.08 to 0.24; I2 = 0%; 11 trials, 595 participants; moderate-certainty evidence). Perceived stress was reduced with MBIs (SMD -0.24 units, 95% CI -0.45 to -0.03; I2 = 0%; P = 0.03; 6 trials, 357 participants; moderate-certainty evidence). There was little to no effect on well-being (SMD -0.18 units, 95% CI -0.67 to 0.32; 1 trial, 63 participants; low-certainty evidence). There was little to no effect on smoking cessation (RR 1.45, 95% CI 0.78 to 2.68; I2 = 79%; 6 trials, 1087 participants; low-certainty evidence). None of the trials reported CVD clinical events or adverse events. MBIs versus non-active comparators (38 RCTs, 2905 participants) Clinical events were reported in one trial (110 participants), providing very low-certainty evidence (RR 0.94, 95% CI 0.37 to 2.42). SBP and DBP were reduced in nine trials (379 participants) but heterogeneity was substantial (SBP: MD -6.62 mmHg, 95% CI -13.15 to -0.1, I2 = 87%; DBP: MD -3.35 mmHg, 95% CI -5.86 to -0.85, I2 = 61%; both outcomes based on low-certainty evidence). There was low-certainty evidence of reductions in anxiety (SMD -0.78 units, 95% CI -1.09 to -0.41; I2 = 61%; 9 trials, 533 participants; low-certainty evidence), depression (SMD -0.66 units, 95% CI -0.91 to -0.41; I2 = 67%; 15 trials, 912 participants; low-certainty evidence) and perceived stress (SMD -0.59 units, 95% CI -0.89 to -0.29; I2 = 70%; 11 trials, 708 participants; low-certainty evidence) but heterogeneity was substantial. Well-being increased (SMD 0.5 units, 95% CI 0.09 to 0.91; I2 = 47%; 2 trials, 198 participants; moderate-certainty evidence). There was little to no effect on smoking cessation (RR 1.36, 95% CI 0.86 to 2.13; I2 = 0%; 2 trials, 453 participants; low-certainty evidence). One small study (18 participants) reported two adverse events in the MBI group, which were not regarded as serious by the study investigators (RR 5.0, 95% CI 0.27 to 91.52; low-certainty evidence). No subgroup effects were seen for SBP, DBP, anxiety, depression, or perceived stress by primary and secondary prevention. TM versus active comparators (8 RCTs, 830 participants) Clinical events were reported in one trial (201 participants) based on low-certainty evidence (RR 0.91, 95% CI 0.56 to 1.49). SBP was reduced (MD -2.33 mmHg, 95% CI -3.99 to -0.68; I2 = 2%; 8 trials, 774 participants; moderate-certainty evidence), with an uncertain effect on DBP (MD -1.15 mmHg, 95% CI -2.85 to 0.55; I2 = 53%; low-certainty evidence). There was little or no effect on anxiety (SMD 0.06 units, 95% CI -0.22 to 0.33; I2 = 0%; 3 trials, 200 participants; low-certainty evidence), depression (SMD -0.12 units, 95% CI -0.31 to 0.07; I2 = 0%; 5 trials, 421 participants; moderate-certainty evidence), or perceived stress (SMD 0.04 units, 95% CI -0.49 to 0.57; I2 = 70%; 3 trials, 194 participants; very low-certainty evidence). None of the trials reported adverse events or smoking rates. No subgroup effects were seen for SBP or DBP by primary and secondary prevention. TM versus non-active comparators (2 RCTs, 186 participants) Two trials (139 participants) reported blood pressure, where reductions were seen in SBP (MD -6.34 mmHg, 95% CI -9.86 to -2.81; I2 = 0%; low-certainty evidence) and DBP (MD -5.13 mmHg, 95% CI -9.07 to -1.19; I2 = 18%; very low-certainty evidence). One trial (112 participants) reported anxiety and depression and found reductions in both (anxiety SMD -0.71 units, 95% CI -1.09 to -0.32; depression SMD -0.48 units, 95% CI -0.86 to -0.11; low-certainty evidence). None of the trials reported CVD clinical events, adverse events, or smoking rates.

AUTHORS' CONCLUSIONS

Despite the large number of studies included in the review, heterogeneity was substantial for many of the outcomes, which reduced the certainty of our findings. We attempted to address this by presenting four main comparisons of MBIs or TM versus active or inactive comparators, and by subgroup analyses according to primary or secondary prevention, where there were sufficient studies. The majority of studies were small and there was unclear risk of bias for most domains. Overall, we found very little information on the effects of meditation on CVD clinical endpoints, and limited information on blood pressure and psychological outcomes, for people at risk of or with established CVD. This is a very active area of research as shown by the large number of ongoing studies, with some having been completed at the time of writing this review. The status of all ongoing studies will be formally assessed and incorporated in further updates.

Dietary and Nutritional Supplementation for Painful Diabetic Neuropathy: A Narrative Review

Painful diabetic neuropathy (PDN) is a serious and very common complication of diabetes mellitus (DM). It negatively affects the quality of life, increases morbidity and poses a financial burden on the health care system. Currently, treatment of PDN focuses on glycaemic control, while pathogenesis-oriented therapy has not yielded satisfactory results. The need to improve therapy remains. There is accumulating evidence on the potential benefit of nutritional interventions. This narrative review aims to examine the potential benefit of dietary and nutritional supplementation for PDN management. According to the preliminary research, supplementation with vitamin E, B-complex, omega-3 fatty acids, CoQ10 or N-acetylcysteine seems to be associated with promising results in improving PDN symptoms.

Structural equation modeling to estimate treatment adherence based on the light triad of personality and sense of coherence in patients with type-2 diabetes: examining the mediating role of psychological well-being

Background

The current study investigated the relationship between the light triad of personality and self-coherence with treatment adherence in patients with Type 2 Diabetes Mellitus (T2DM) using Structural Equation Modeling (SEM). Psychological well-being was considered a mediator variable in this SEM assessment.

Method

A cross-sectional study by convenience sampling was conducted, and 368 patients with T2DM were recruited from 10 private practice and general hospitals from May to November 2021 in Gilan province, Iran. The Reef's Psychological Well-being Questionnaire, the Light Triad Rating Scale, and Antonovsky's Sense of Coherence Scale were used for data collection. Structural equation modeling was used to examine the model fitness and identify direct/indirect relationships among variables. Data were analyzed by the SPSS (Version 26) and AMOS software (Version 24).

Results

The average score of light triads, sense of coherence, psychological well-being, and treatment adherence were 70.36 ± 25.55, 108.25 ± 37.68, 57.03 ± 23.84, and 106.81 ± 39.61, respectively. Model fit statistics suggest that the measurement model fits the data well: χ2 (146, N = 368) = 314.011 (p < 0.001). The SEM results showed that the light triad of personality (β = 0.12) and self-coherence (β = 0.14) were positively associated with treatment adherence. Anxiety, the light triad of personality (β = 0.12), and self-coherence (β = 0.14) affect treatment adherence indirectly through psychological well-being.

Conclusion

The analysis of the SEM revealed that the suggested model had a suitable goodness of fit. So, using self-coherence and psychological well-being structures in designing interventional programs is recommended to optimize treatment adherence in patients with T2DM.

Adverse effect propensity: A new feature of Gulf War illness predicted by environmental exposures

A third of 1990-1 Gulf-deployed personnel developed drug/chemical-induced multisymptom illness, "Gulf War illness" (GWI). Veterans with GWI (VGWI) report increased drug/exposure adverse effects (AEs). Using previously collected data from a case-control study, we evaluated whether the fraction of exposures that engendered AEs ("AE Propensity") is increased in VGWI (it was); whether AE Propensity is related to self-rated "chemical sensitivity" (it did); and whether specific exposures "predicted" AE Propensity (they did). Pesticides and radiation exposure were significant predictors, with copper significantly "protective"-in the total sample (adjusted for GWI-status) and separately in VGWI and controls, on multivariable regression. Mitochondrial impairment and oxidative stress (OS) underlie AEs from many exposures irrespective of nominal specific mechanism. We hypothesize that mitochondrial toxicity and interrelated OS from pesticides and radiation position people on the steep part of the curve of mitochondrial impairment and OS versus symptom/biological disruption, amplifying impact of new exposures. Copper, meanwhile, is involved in critical OS detoxification processes.

Effect of Cognitive-Behavioral Therapy or Mindfulness Therapy on Pain and Quality of Life in Patients with Diabetic Neuropathy: A Systematic Review and Meta-Analysis

OBJECTIVES

This study aimed to evaluate the effectiveness of cognitive behavioral therapy (CBT) and mindfulness therapy (MT) for pain relief and quality of life (QOL) in patients with diabetic neuropathy.

REVIEW/ANALYSIS METHODS

Four databases were systematically searched from their respective inception dates to 29 June 2021. Relevant randomized controlled trials (RCTs) were screened and assessed for risk of bias. Eight RCTs evaluating CBT or MT were included. Statistical analysis was performed using Review Manager 5.4.

RESULTS

Eight RCTs involving 384 patients with painful diabetic neuropathy (PDN) tested psychological interventions, including three CBT and five MT studies. The results showed that patients' pain severity (standardized mean difference [SMD] = -0.60, 95% confidence interval [CI; -0.93 to -0.27], P = .0003) and QOL (SMD = -0.43, 95% CI [-0.83 to -0.04], p = .03) were improved immediately after treatment. Besides, the pain intensity (SMD = -0.67, 95% CI [-1.37 to 0.03], p = .06), pain interference (SMD = -0.75, 95% CI [-1.20 to -0.30], p = .001) and depressive symptoms (SMD = -0.62, 95% CI [-0.96 to -0.28], p = .0003) were superior to the control group after follow up. The subgroup analysis results of different intervention type showed that the CBT group could immediately improve pain (SMD = -0.44, 95% CI [-0.78 to -0.10], p = .01) after treatment. However, there was no statistically significant difference in the CBT group after follow-up (SMD = -0.15, 95% CI [-0.52 to 0.22], p = .42).

CONCLUSIONS

Cognitive behavioral therapy or MT is effective for treating pain in patients with diabetic peripheral neuropathy, improving the QOL, and reducing depressive symptoms. However, large-scale, multi-centre, rigorously designed RCTs are needed to further verify the long-term effects.

Pharmacotherapy of Painful Diabetic Neuropathy: A Clinical Update

The rising prevalence of diabetes mellitus (DM) leads on to an increase in chronic diabetic complications. Diabetic peripheral neuropathies (DPNs) are common chronic complications of diabetes. Distal symmetric polyneuropathy is the most prevalent form. Most patients with DPN will remain pain-free; however, painful DPN (PDPN) occurs in 6-34% of all DM patients and is associated with reduced health-related-quality-of-life and substantial economic burden. Symptomatic treatment of PDPN and diabetic autonomic neuropathy is the key treatment goals. Using certain patient related characteristics, subjects with PDPN can be stratified and assigned targeted therapies to produce better pain outcomes. The aim of this review is to discuss the various pathogenetic mechanisms of DPN with special reference to the mechanisms leading to PDPN and the various pharmacological and non-pharmacological therapies available for its management. Recommended pharmacological therapies include anticonvulsants, antidepressants, opioid analgesics, and topical medications.

Influence of Vitamin D Supplementation on Mental Health in Diabetic Patients: A Systematic Review

Diabetes is associated with a number of mental health consequences, including enhanced risk of depression and anxiety, as well as decreased quality of life, and vitamin D deficiency is considered to be one of the factors that influence these outcomes in diabetic patients. The aim of the present study was to conduct a systematic review of the literature presenting the data regarding the influence of vitamin D supplementation on mental health in diabetic adults. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (Registration number CRD42020155779). A systematic search of the PubMed and Web of Science databases was performed, and the intervention studies published until September 2021 were included in the review. The human studies were included if an adult sample of diabetic individuals received vitamin D supplementation during the intervention and its effect on any mental health aspect was assessed, but studies presenting the influence of combined supplementation of multiple nutrients were excluded. After removing duplicate records, a total of 8514 publications were screened and assessed independently by two researchers, based on their title, abstract, and full text. Finally, six studies were included in the current systematic review, and the risk of bias was evaluated using the Newcastle–Ottawa Scale (NOS). The included studies analyzed the influence of a specific dose of vitamin D, or different doses of vitamin D, or compared the results of supplementation with a specific dose of vitamin D against the placebo group. The supplementation was performed for at least 12 weeks. The mental health outcomes analyzed in these studies included health-related quality of life, depression, anxiety, stress, and general mental health status of adult diabetic patients. The results of the majority of the studies confirmed the positive influence of vitamin D supplementation on the mental health of diabetic individuals. Those studies that analyzed the influence of vitamin D supplementation on depression and anxiety established the beneficial effect of the vitamin. In some studies, the influence of vitamin D supplementation on the health-related quality of life was not considered unless combined with mindfulness training. However, it must be emphasized that different dosage regimens and intervention periods were followed in the reviewed studies, and only a small number of studies were randomized against placebo, which should be considered as a limitation of the present study. The findings of the conducted systematic review demonstrated the positive influence of vitamin D supplementation on the mental health of diabetic patients, which was proved for anxiety and depression, but in the case of health-related quality of life, the positive effect was observed only when the intervention included mindfulness training. These outcomes suggest that supplementation should be recommended to improve the vitamin D status and the mental health of patients in this group.

Predicting the quality of life based on pain dimensions and psychiatric symptoms in patients with Painful diabetic neuropathy: a cross-sectional prevalence study in Iranian patients

Background

This study aimed to predict the quality of life (QOL) in patients with Painful Diabetic Neuropathy (PDN) based on pain severity, pain catastrophizing, pain acceptance, depression, anxiety, and sleep disturbance. Also, this study was aimed to assess the prevalence of psychiatric symptoms in Iranian patients with PDN.

Method

1120 patients (mean age, 53.6 ± 12.6 years) participated in the research. Data were collected by the Quality of life questionnaire (NeuroQoL); Beck Depression Inventory, Beck Anxiety Inventory, the visual analog scale for pain severity, Pain Catastrophizing Scale (PCS), Chronic Pain Acceptance Questionnaire (CPAQ) and Pittsburgh Sleep Quality Index (PSQI). Finally, the data were analyzed using SPSS-26 by multiple regression analysis.

Results

The results showed the regression models’ significance, and the dependent variables predicted 42% of total changes in the QOL. The most significant predicting factors were depression, pain catastrophizing, pain acceptance, pain severity, sleep disturbance, and anxiety in order. In patients with PDN, the prevalence of sleep disturbances, depression, and anxiety were 85.5%, 68.2%, and 62.1%, respectively. Also, comorbid depression and anxiety were found in 47% of patients.

Conclusion

Results demonstrated a significant relationship between pain-related and psychiatric dimensions with QOL. Thus, it is suggested to design more specific psychological-based rehabilitation interventions in which these variables are considered. They should focus on more significant variables (such as depression and pain catastrophizing) to reach better treatment outcomes. Furthermore, this research shows a high level of anxiety, depression, and sleep disturbance in Iranian patients with PDN. Thus, experts and clinicians are suggested to focus on reducing these psychiatric symptoms.