Effects and feasibility of hyperthermic baths in comparison to exercise as add-on treatment to usual care in depression: a randomised, controlled pilot study

The impact of exercise interventions on sleep in adult populations with depression, anxiety, or posttraumatic stress: review of the current evidence and future directions

Consistent evidence suggests that exercise leads to improvements in subjective sleep quality and also objective sleep metrics in non-psychiatric adult populations. However, the degree to which exercise provides sleep benefits for adults with psychiatric disorders is less known, despite the potential benefits given that sleep disturbance is prevalent in these populations. In this narrative review, we synthesize results of randomized controlled trials examining the influence of aerobic and/or resistance exercise interventions on sleep outcomes in adult psychiatric populations. We specifically focus on populations with elevated symptoms or diagnoses of depression, anxiety, or posttraumatic stress disorder. A systematic search through June 2024 yielded 26 relevant trials. Overall, most trials reported improvement of subjective sleep quality after aerobic and/or resistance exercise programs in samples with depression. Similar effects were observed for posttraumatic stress; however, larger trials are needed. Further research is needed to examine the impact of exercise on sleep in anxiety populations as only one trial with mixed results was identified. Results were more equivocal for the subpopulation of adult women with perinatal or postpartum depression, demonstrating the importance of understanding exercise effects on sleep in specific subpopulations. Few studies examined objective sleep outcomes, impact of acute exercise on next day sleep, or the interplay between exercise, sleep, and psychiatric symptom changes, all important areas of future research. Other implications and future directions are discussed, including potential moderators and mechanisms of action that warrant further study to better understand how exercise interventions may optimally target sleep in psychiatric populations.

Greater severity of depressive symptoms is associated with changes to perceived sweating, preferred ambient temperature, and warmth-seeking behavior

The thermosensory system is relevant to both the conceptualization and treatment of depression. There is evidence that depression is associated with changes in thermoregulatory functioning, and that thermosensory pathways can be recruited to influence affect and reduce depressive symptoms. In this study, we investigated the relationship between severity of depressive symptoms and changes to measures of subjective experiences associated with thermoregulatory processes as well as the relationship between severity of depressive symptoms and affective responses to warm stimuli, specifically frequency of warmth-seeking behavior. Participants (N = 529) completed measures of depressive symptoms, subjective experiences associated with thermoregulatory processes (i.e., perceived sweating and preferred ambient temperature) and frequency of warmth-seeking behavior (e.g., long hot baths, saunas, etc.). We demonstrate that, controlling for age and gender, greater severity of depressive symptoms is associated with greater perceived sweating and lower preferred ambient temperature. Furthermore, we demonstrate that greater severity of depressive symptoms is associated with more frequent warmth-seeking behavior, and that something other than thermal preference (i.e., stated preference for warmer temperature) is driving this behavior. These data highlight the importance of incorporating the thermoregulatory system in our conceptualization of the pathophysiology of depression and support the potential to recruit thermosensory pathways to target depressive symptoms.

A computationally informed distinction of interoception and exteroception

While interoception is of major neuroscientific interest, its precise definition and delineation from exteroception continue to be debated. Here, we propose a functional distinction between interoception and exteroception based on computational concepts of sensor-effector loops. Under this view, the classification of sensory inputs as serving interoception or exteroception depends on the sensor-effector loop they feed into, for the control of either bodily (physiological and biochemical) or environmental states. We explain the utility of this perspective by examining the perception of skin temperature, one of the most challenging cases for distinguishing between interoception and exteroception. Specifically, we propose conceptualising thermoception as inference about the thermal state of the body (including the skin), which is directly coupled to thermoregulatory processes. This functional view emphasises the coupling to regulation (control) as a defining property of perception (inference) and connects the definition of interoception to contemporary computational theories of brain-body interactions.

Severity of depressive symptoms moderates the sympathoinhibitory effect of local skin warming following exposure to a social stressor

Depression is the leading cause of disease burden globally. Existing antidepressant treatments that target the central nervous system have limited efficacy and come at the cost of significant side effects. Thus, there is growing interest in novel therapeutic interventions for the prevention and treatment of depression, including interventions that target interoceptive signaling. The thermosensory system may hold particular promise, given evidence that depression is associated with impairments in thermosensory functioning, and that whole-body hyperthermia produces an antidepressant effect in patients with major depressive disorder. In this study, we investigated whether the severity of depressive symptoms in a non-clinical population moderated the effect of local skin warming on subjective and physiological stress responses following exposure to an acute social stressor. Following exposure to the stressor, participants (N = 90) rested their arm on a heat blanket that was either turned on (local skin warming condition) or left off (control condition). We demonstrate that local skin warming increased fingertip temperature, a marker of reduced sympathetic nervous system activity, but only for participants with high levels of depressive symptoms. While local skin warming also inhibited salivary alpha amylase, severity of depressive symptoms did not moderate this effect, and no effect was found for electrodermal activity. These data highlight the importance of incorporating peripheral physiology in our conceptualization of the pathophysiology of depression and show that changes in sympathetic nervous system activity may underpin the antidepressant effect of warm stimuli.

The novel design of an intelligent anti-depression transdermal drug delivery system

Depression is a type of mental disorder with a significant and persistent low mood as the main clinical feature. It is often accompanied by symptoms such as slow thinking, decreased will, loss of appetite, and weight loss. The current treatment methods for depression are mainly medical treatment, psychotherapy, and physical therapy. These treatments are dependent on the patient's autonomy and the patients may suspend treatment due to forgetting or refusing. Therefore, an anti-depressant intelligent drug release system was designed, which can achieve autonomously controlled doses for the treatment of depression by transdermal drug delivery system. The work of this study is as follows: (1) The first module: the electrothermal material heating layer. Several preparation methods were screened, and multiple sets of graphene (GE) electric thermogenic layers were successfully prepared. After increasing the actual energization area to 1 cm × 1 cm, the GE electric thermogenic layer is used as the heating layer of the electrothermal material of the system, and can reach a uniform surface temperature of (45 ± 0.5) °C within 15 s at a voltage of 6 V keeping the temperature fluctuation range not exceeding ±0.03 °C, and the resistance fluctuation range not exceeding ±20 Ω, which plays a role in controlling the temperature and heat treatment of the drug loaded gel layer. (2) The second module: the drug-loaded gel layer. Based on the L16 (45) orthogonal test, the best formulation and process of N-Isopropyl acrylamide-Acrylamide copolymer (P(NIPAAm-co-AAm)) hydrogel was determined. Then, the percutaneous permeability of Selegiline liposome was studied in vitro. (3) A rat model of depression was established using chronic unpredictable mild stress (CUMS) combined with separation. From the aspects of behavior (body weight, sucrose preference test, forced swimming test, open field test) and biochemical indexes (serum proinflammatory cytokines (IL-1β, TNF-α), hippocampus HE staining observation), the therapeutic effect of hyperthermia, Selegiline oral administration and transdermal administration was discussed.

Feasibility and pilot study of passive heat therapy on cardiovascular performance and laboratory values in older adults

BACKGROUND

Chronic heat therapy may have beneficial effects on cardiovascular function. These effects may be more pronounced in older adults. We performed a pilot feasibility study of repeated heat therapy sessions in a hot tub (40.5 °C) in older adults while wearing a noninvasive hemodynamic monitor. As part of the protocol, the volunteers underwent cardiovascular performance testing pre- and post-intervention.

METHODS

Fifteen volunteers > 50 years old underwent 8-10 separate 45-min hot tub session over 14 days in this exploratory and mixed methods trial. The participants had maximal oxygen consumption (VO₂ max) and other cardiovascular data measured via exercise treadmill testing prior to and after all hot tub sessions. The participants also wore noninvasive fingertip volume clamp monitors while immerged in hot water that calculated systemic vascular resistance, heart rate, blood pressure, and cardiac output in order to ascertain the feasibility and utility of this data. Other laboratory studies were obtained pre- and post-intervention. The protocol was determined feasible if the heat therapy and cardiovascular testing was completed by at least 90% (14/15 subjects). Feasibility of the noninvasive monitor was determined by the fidelity of the results. Secondary exploratory outcomes were analyzed for differences to identify if they are acceptable to include in an efficacy trial.

RESULTS

All participants completed the study protocol identifying the feasibility of the protocol. The noninvasive hemodynamic monitors successfully recorded cardiac output, systemic vascular resistance, heart rate, and blood pressure with fidelity based on the analysis of recordings. In the secondary analyses, we found no difference in the pre- to post-intervention measurement of VO₂ max but did find increased exercise duration following hot tub therapy compared with prior to the therapy (571 s versus 551 s).

CONCLUSIONS

The current pilot study protocol is feasible for the purpose of analyzing the effects of heat therapy and cardiovascular performance in older adults while wearing a noninvasive hemodynamic monitor and undergoing treadmill stress testing. Secondary analyses found increased exercise tolerance but no differences in VO₂ max following heat sessions.

Association of plasma cytokines and antidepressant response following mild-intensity whole-body hyperthermia in major depressive disorder

Whole-body hyperthermia (WBH) shows promise for the treatment of major depressive disorder (MDD). Because MDD is associated with increased inflammation, and anti-inflammatory agents show some promise as antidepressants, the current study sought to identify the acute and longer-term immune effects of WBH in participants with MDD and to explore whether these effects associate with the procedure's antidepressant properties. Thirty participants who met DSM-IV-TR criteria for MDD were randomized to receive a single session of WBH (n = 16) or sham treatment (n = 14). Hamilton Depression Rating Scale (HDRS) scores were assessed at baseline and 1, 2, 4, and 6 weeks post-treatment (WBH vs. sham), and plasma cytokine concentrations were assessed at baseline, immediately post-treatment, and 1 and 4 weeks post-treatment. As previously reported, WBH produced a rapid and sustained antidepressant effect. When compared to sham, WBH increased plasma interleukin (IL)-6 immediately post-treatment (time by treatment: χ²_{(3, N=108)} = 47.33, p < 0.001), while having no effect on other cytokines acutely and no impact on IL-6, or any other cytokine, at 1 or 4 weeks post treatment. In the study sample as a whole, increased IL-6 post-treatment was associated with reduced HDRS depression scores over the 6 weeks of follow-up (F_{(1, 102.3)} = 6.74, p = 0.01). These results suggest a hitherto unrecognized relationship between hyperthermia, the immune system, and depression, and may point to WBH as a novel modality for exploring behavioral effects of IL-6 when the cytokine is activated in isolation from the inflammatory mediators with which it frequently travels.

Association between habitual hot spring bathing and depression in Japanese older adults: A retrospective study in Beppu

OBJECTIVES

Thermal therapy is used to manage various psychological diseases, such as depression. We investigated the relationship between hot spring bathing and depression in older adults using questionnaire responses.

DESIGN AND SETTING

We comprehensively evaluated the preventive effects of long-term hot spring bathing in 10429 adults aged ≥ 65 years in Beppu, Japan, by conducting a questionnaire study on the prevalence of depression (n = 219).

MAIN OUTCOME MEASURES

Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a multivariable logistic regression model for history of depression.

RESULTS

A separate multivariable logistic regression model for inference showed that female sex (OR, 1.56; 95 % CI, 1.17-2.08; p = 0.002), arrhythmia (OR, 1.73; 95 % CI, 1.18-2.52; p = 0.004), hyperlipidemia (OR, 1.63; 95 % CI, 1.14-2.32; p = 0.006), renal disease (OR, 2.26; 95 % CI, 1.36-3.75; p = 0.001), collagen disease (OR, 2.72; 95 % CI, 1.48-5.02; p = 0.001), allergy (OR, 1.97; 95 % CI, 1.27-3.04; p = 0.002), and habitual daily hot spring bathing (OR, 0.63; 95 % CI, 0.41-0.94; p = 0.027) were independently significantly associated with a history of depression.

CONCLUSIONS

We found an inverse relationship between habitual daily hot spring bathing and history of depression. Prospective randomized controlled trials on habitual daily hot spring bathing as a treatment for depression are warranted to investigate whether the use of hot springs can provide relief to those with psychiatric and mental health disorders.

The effects of immersion in 42℃ radon, natrium, calcium, bicarbonate content thermal-mineral water on chronic low back pain. Controlled, follow-up study

In our minimized follow-up trial with 137 participants with chronic low back pain, one group of participants received regular outpatient care, and the other group received balneotherapy by immersion in 42℃ thermal-mineral water in addition to regular outpatient care on 15 occasions for 3 weeks. Pain on movement and at rest on the 0-100 mm visual analogue scale (VAS), Oswestry index, the number of participants evaluating the symptoms clinically acceptable (Patient Acceptable Symptom State, PASS) and the EuroQol-5D-5L (EQ-5D-5L) quality of life questionnaire were assessed at basal time (at week 0) and after balneotherapy (at weeks 3 and 12). The VAS pain scores, the Oswestry index, the EQ-5D-5L index and the EQ-VAS significantly improved in the balneotherapy group after treatment at week 3 (p < 0.001) and week 12 (p < 0.001) compared to baseline, with a significant between group difference at week 3 (p < 0.001) and week 12 (p < 0.001). The pain VAS score on movement was 66.82 ± 11.48, 26.69 ± 21.49, and 20.09 ± 23.29 in the balneotherapy group, and 63.67 ± 14.77, 67.35 ± 15.44, and 70.23 ± 18.26 in the control group at the consecutive visits. The PASS increased in both groups at week 3 and week 12 compared to the baseline, with a significant between-group difference at week 3 and week 12 for the balneotherapy group. Our results suggest the therapeutic efficacy of immersion in 42℃ thermal mineral water on chronic low back pain.ClinicalTrials.gov Identifier: NCT05342051.

Sleep and spa therapies: What is the role of balneotherapy associated with exercise? A systematic review

Balneotherapy and exercise are potential factors influencing sleep through several physiological pathways and relaxing effects. This review aims to assess whether balneotherapy can improve sleep quality in concomitance or not with exercise. The research was conducted on Medline, Scopus, PubMed, Web of Science, and Cochrane Library databases. The current review followed PRISMA reporting guidelines and involves twenty-one articles grouped into four sections based on the characteristics of the balneotherapy protocol: 1.a Balneotherapy-thermal water immersion alone (five studies); 1.b Balneotherapy-thermal water immersion with other spa treatments (six studies); 2.a Balneotherapy and physical exercise-balneotherapy and out-of-the-pool physical exercise (eight studies); 2.b Balneotherapy and physical exercise-balneotherapy and in-pool physical exercise (three studies). Apart from healthy or sub-healthy subjects, patients recruited in the studies were affected by fibromyalgia, ankylosing spondylitis, osteoarthritis, musculoskeletal pain, subacute supraspinatus tendinopathy, and mental disorders. Duration, number of sessions, and study protocols are very different from each other. Only one study objectively evaluated sleep, whereas the others used subjective sleep assessment methods. Eight studies considered sleep as a primary outcome and ten as secondary. Sixteen out of twenty-one studies described improvements in self-perceived sleep quality. Thus, balneotherapy associated with other spa treatments and physical exercise seems to be effective in improving self-perceived sleep quality. However, the miscellany of treatments makes it difficult to discern the isolated effects of balneotherapy and physical exercise. Future studies should consider using an objective sleep assessment method and describing the pathways and physiological mechanisms that could provoke sleep changes during balneotherapy treatments.

Massage and touch-based therapy : Clinical evidence, neurobiology and applications in older patients with psychiatric symptoms

Background

Massage and touch-based treatment are popular despite limited evidence from high quality clinical trials. This article reviews the rationale and evidence of treating older patients with psychiatric symptoms by touch-based therapy.

Methods

Narrative literature review, based on Medline search with the following key words: massage, social touch, affective touch, clinical trial, meta-analysis. Citations of identified articles were searched for additional relevant studies.

Results

Evidence from clinical trials in adult patients with mainly chronic disorders of the musculoskeletal system suggests that massage therapy results in significant short-term improvement of symptoms; however, treatment effects appear not to be sustained. In addition, conclusions are difficult to draw owing to very heterogeneous study interventions, difficulties with definition of control conditions and treatment outcomes. There appears to be better evidence for improvement of psychological variables and subjective symptoms, such as pain and quality of life. A neuronal system of affective and social touch has been identified with specific afferents from C‑fibre coupled low threshold mechanoreceptors projecting into the insular cortex and the limbic system. This system may also mediate effects of massage in adult patients. Positive clinical trials for depressive symptoms of dementia and for behavioral symptoms of advanced dementia are available with encouraging results.

Conclusion

The neuronal system of social and affective touch suggests a potential mechanism of action of touch-based interventions in geriatric psychiatry. In addition, it provides a rationale for applying and designing novel touch-based treatment strategies as adjunctive treatment for psychiatric disorders of old age.

Italian and Japanese public attention toward balneotherapy in the COVID-19 era

Italian and Japanese public widely use balneotherapy. The population interest in balneotherapy in coronavirus disease-2019 (COVID-19) era should be investigated. Therefore, we aimed to exploit Google Trends analysis, as a measure of peoples' interest in balneotherapy, in two countries, Italy and Japan. In this infodemiology study, Google Trends was queried for the lay terms widely used by the Italian population to refer to the balneotherapy setting (terme + termale) and by the Japanese to refer to the bathing place and balneotherapy facilities ( + スパ). The internet searches in 2020 were compared to overlapping time spans in 2016-2019 and were correlated with new confirmed cases/deaths. This study demonstrated that from February 23 to June 20, 2020, and from October 4 to December 26, 2020, the internet searches of the Italian words corresponding to balneotherapy were statistically significantly decreased; however, the internet searches were not significantly different in June 21 to October 3, 2020, compared to overlapping time spans in 2016-2019 in Italy. The study also showed that from March 15 to September 5, 2020, and from November 29 to December 26, 2020, the internet searches of the Japanese words corresponding to balneotherapy were statistically significantly decreased; however, the internet searches were significantly increased in September 13 to November 7, 2020, and were not significantly different in November 8 to 28, 2020, compared to overlapping time spans in 2016-2019 in Japan. There were significant negative correlations between the relative search volume and number of new cases (rho=-0.634; p<0.001)/deaths (rho=-0.856; p<0.001) in Italy and the number of new deaths (rho=-0.348; p=0.012) in Japan. Population interest in balneotherapy has changed in the COVID-19 era both in Italy and Japan. During the early stage of pandemic (March to June), the interest was lower. After this early stage, the interest showed a recovery in both countries. In Italy, the population interest reached to its prior levels in late June through early October, with a peak in August. In Japan, the recovery exceeded the prior 4-year levels in mid-September through early November. Then, both countries demonstrated a decline in interest: began in early October in Italy and late November in Japan. This information would allow us to understand/address the population response in the pandemic in respect of the balneotherapy and would guide the preparedness of healthcare providers and planners both in this pandemic and future similar situations.