Transcranial direct current stimulation combined with physical or cognitive training in people with Parkinson's disease: a systematic review

BACKGROUND

Pharmacologic therapy is the primary treatment used to manage Parkinson's disease (PD) symptoms. However, it becomes less effective with time and some symptoms do not respond to medication. Complementary interventions are therefore required for PD. Recent studies have implemented transcranial direct current stimulation (tDCS) in combination with other modalities of interventions, such as physical and cognitive training. Although the combination of tDCS with physical and cognitive training seems promising, the existing studies present mixed results. Therefore, a systematic review of the literature is necessary.

AIMS

This systematic review aims to (i) assess the clinical effects of tDCS when applied in combination with physical or cognitive therapies in people with PD and; (ii) analyze how specific details of the intervention protocols may relate to findings.

METHODS

The search strategy detailed the technique of stimulation, population and combined interventions (i.e. cognitive and/or physical training). Only controlled studies were included.

RESULTS

Seventeen of an initial yield of 408 studies satisfied the criteria. Studies involved small sample sizes. tDCS protocols and characteristics of combined interventions varied. The reviewed studies suggest that synergistic effects may be obtained for cognition, upper limb function, gait/mobility and posture when tDCS is combined with cognitive and/or motor interventions in PD.

CONCLUSION

The reported results encourage further research to better understand the therapeutic utility of tDCS and to inform optimal clinical use in PD. Future studies in this field should focus on determining optimal stimulation parameters and intervention characteristics for maximal benefits in people with PD.

Acute Sildenafil Use Reduces 24-Hour Blood Pressure Levels in Patients With Resistant Hypertension: A Placebo-Controlled, Crossover Trial

The authors previously demonstrated that acute administration of sildenafil-a phosphodiesterase 5 (PDE5) inhibitor-improves hemodynamic parameters in patients with resistant hypertensive (RH), but its effect on ambulatory blood pressure monitoring (ABPM) is unknown. This interventional, nonrandomized, single-blinded, placebo-controlled, crossover trial included 26 patients with RH. A dose of sildenafil (187.5mg) was given, and after a washout period of 14 days the patients received a single oral dose of placebo and the protocol was repeated. The patients underwent 24-hour ABPM recordings the day before and immediately after the protocols. The reduction of systolic (-8.8±1.4 vs 1.3±1.2 mm Hg, P=.02), diastolic (-5.3±3.3 vs 1.8±1.1 mm Hg, P=.03), and mean (-7.9±3.6 vs 0.8±0.9 mm Hg, P=.01) 24-hour BP were found after the use of sildenafil compared with placebo. Improvement in daytime BP levels was also observed (systolic -6.0±4.7 vs 4.4±1.5 mm Hg [P=.02] and mean -4.8±3.9 vs 3.5±1.4 mm Hg [P=.02] for sildenafil vs placebo, respectively). Considering its antihypertensive effect, sildenafil may represent a therapeutic option for RH treatment.

Mental health resilience in offspring of depressed parents: a systematic literature review protocol

BACKGROUND

Parental depression is associated with a range of mental health conditions and other difficulties in the offspring. Nevertheless, some offspring exposed to parental depression do not develop mental health problems, indicating the presence of protective factors that may buffer parental depression-related risk effects. However, evidence of protective factors that might explain good sustained mental health in offspring of depressed parents is limited and systematic synthesis of these factors is still needed. Therefore, as far as we are aware, this will be the first systematic review that will identify parent, family, child, social, and lifestyle factors associated with mental health resilience in offspring of depressed parents, examine evidence for sex-, developmental stage-, and outcome-specific factors and define mental health resilience in the parental depression context.

METHODS

This protocol has been developed according to the PRISMA-P guidelines. Electronic searches will be performed for articles published up to 2022 in PsycINFO, Embase, MEDLINE, Web of Science Core Collection, and Cochrane Library. Two reviewers will independently screen titles/abstracts and full-texts against eligibility criteria, extract the data, and assess the overall quality of evidence. Both observational and RCT studies will be eligible for inclusion if they report offspring mental health resilience/outcome and depressive symptoms or depressive disorder in at least one of the parents/caregivers. Risk of bias will be assessed using The Joanna Briggs Institute (JBI) critical appraisal checklists and The Revised Cochrane risk of bias tool for randomised trials (RoB 2). It is expected that studies will be heterogeneous; therefore, meta-analysis will not be attempted. Studies will be systematically retrieved and collated using numerical, graphical, tabular, and narrative summaries and grouped by their design, scope, or overall quality. Further sub-group analyses will be performed to examine sex-, developmental stage-, and outcome-specific protective factors.

DISCUSSION

The proposed systematic review will be the first to summarise and critically assess quality and strength of evidence of protective factors associated with mental health resilience in offspring of depressed parents. Directions and effect sizes of the protective factors will be discussed as well as differences between the studies, their limitations, and research gaps and future directions. Strengths and limitations of the proposed systematic review will be also discussed. The proposed systematic review findings are expected to help better understand mental health resilience and identify targets for evidence-based prevention and intervention strategies for those in need.

SYSTEMATIC REVIEW REGISTRATION

A previous version of this systematic review protocol has been registered in the International Prospective Register of Systematic Reviews (PROSPERO) database ( www.crd.york.ac.uk/PROSPERO , CRD42021229955).