Both cardiovascular and cerebrovascular events are decreased following long-term narrowband ultraviolet B phototherapy in patients with vitiligo: a propensity score matching analysis

Phototherapy for vitiligo: A narrative review on the clinical and molecular aspects, and recent literature

BACKGROUND

Vitiligo is characterized by depigmented patches resulting from loss of melanocytes. Phototherapy has emerged as a prominent treatment option for vitiligo, utilizing various light modalities to induce disease stability and repigmentation.

AIMS AND METHODS

This narrative review aims to explore the clinical applications and molecular mechanisms of phototherapy in vitiligo.

RESULTS AND DISCUSSION

The review evaluates existing literature on phototherapy for vitiligo, analyzing studies on hospital-based and home-based phototherapy, as well as outcomes related to stabilization and repigmentation. Narrowband ultra-violet B, that is, NBUVB remains the most commonly employed, studied and effective phototherapy modality for vitiligo. Special attention is given to assessing different types of lamps, dosimetry, published guidelines, and the utilization of targeted phototherapy modalities. Additionally, the integration of phototherapy with other treatment modalities, including its use as a depigmenting therapy in generalized/universal vitiligo, is discussed. Screening for anti-nuclear antibodies and tailoring approaches for non-photo-adapters are also examined.

CONCLUSION

In conclusion, this review provides a comprehensive overview of phototherapy for vitiligo treatment. It underscores the evolving landscape of phototherapy and offers insights into optimizing therapeutic outcomes and addressing the challenges ahead. By integrating clinical evidence with molecular understanding, phototherapy emerges as a valuable therapeutic option for managing vitiligo, with potential for further advancements in the field.

Photo-neuro-immuno-endocrinology: How the ultraviolet radiation regulates the body, brain, and immune system

Ultraviolet radiation (UVR) is primarily recognized for its detrimental effects such as cancerogenesis, skin aging, eye damage, and autoimmune disorders. With exception of ultraviolet B (UVB) requirement in the production of vitamin D3, the positive role of UVR in modulation of homeostasis is underappreciated. Skin exposure to UVR triggers local responses secondary to the induction of chemical, hormonal, immune, and neural signals that are defined by the chromophores and extent of UVR penetration into skin compartments. These responses are not random and are coordinated by the cutaneous neuro-immuno-endocrine system, which counteracts the action of external stressors and accommodates local homeostasis to the changing environment. The UVR induces electrical, chemical, and biological signals to be sent to the brain, endocrine and immune systems, as well as other central organs, which in concert regulate body homeostasis. To achieve its central homeostatic goal, the UVR-induced signals are precisely computed locally with transmission through nerves or humoral signals release into the circulation to activate and/or modulate coordinating central centers or organs. Such modulatory effects will be dependent on UVA and UVB wavelengths. This leads to immunosuppression, the activation of brain and endocrine coordinating centers, and the modification of different organ functions. Therefore, it is imperative to understand the underlying mechanisms of UVR electromagnetic energy penetration deep into the body, with its impact on the brain and internal organs. Photo-neuro-immuno-endocrinology can offer novel therapeutic approaches in addiction and mood disorders; autoimmune, neurodegenerative, and chronic pain-generating disorders; or pathologies involving endocrine, cardiovascular, gastrointestinal, or reproductive systems.

Impact of ultraviolet radiation on cardiovascular and metabolic disorders: The role of nitric oxide and vitamin D

BACKGROUND/PURPOSE

Ultraviolet (UV) radiation has both harmful and beneficial effects on human skin and health. It causes skin damage, aging, and cancer; however, it is also a primary source of vitamin D. Additionally, UV radiation can impact energy metabolism and has protective effects on several cardiovascular and metabolic disorders in mice and humans. However, the mechanisms of UV protection against these diseases have not been clearly identified.

METHODS

This review summarizes the systemic effects of UV radiation on hypertension and several metabolic diseases such as obesity, diabetes, and nonalcoholic fatty liver disease (NAFLD) in mice, and we also consider the mechanisms of action of the related regulators nitric oxide (NO) and vitamin D.

RESULTS

UV exposure can lower blood pressure and prevent the development of cardiovascular diseases and metabolic disorders, such as metabolic syndrome, obesity, and type 2 diabetes, primarily through mechanisms that depend on UV-induced NO. UV radiation may also effectively delay the onset of type 1 diabetes through mechanisms that rely on UV-induced vitamin D. UV-induced NO and vitamin D play roles in preventing and slowing the progression of NAFLD.

CONCLUSION

UV exposure is a promising nonpharmacological intervention for cardiovascular and metabolic disorders. NO and vitamin D may play a crucial role in mediating these effects. However, further investigations are required to elucidate the exact mechanisms and determine the optimal dosage and exposure duration of UV radiation.

Association between cardio-cerebrovascular disease and systemic antipsoriatic therapy in psoriasis patients using population-based data: A nested case-control study

The effect of antipsoriatic therapy on cardio-cerebrovascular disease (CCVD) is not well described. Thus, we performed a population-based nested case-control study to investigate the effect of systemic antipsoriatic therapy on CCVD in psoriasis patients. Using nationwide cohort data from the Korean National Health Insurance Claims database, newly diagnosed psoriasis patients were identified. Among the enrolled participants, postenrollment development of CCVD events (ischemic heart disease, myocardial infarction, cerebral infarction, and cerebral hemorrhage) was investigated. To evaluate the effect of systemic antipsoriatic therapy on CCVD risk, we calculated the proportion of the treatment period with systemic antipsoriatic therapy during the study period (PTP [%]: the sum of all systemic antipsoriatic therapy durations divided by total observation period). Among 251 813 participants, 6262 experienced CCVD events during the study period (CCVD group). Controls included 245 551 patients without CCVD history during the study period (non-CCVD group). The non-CCVD group had greater PTP than the CCVD group (CCVD 2.12 ± 7.92, non-CCVD 2.64 ± 9.64; P < 0.001). In multiple logistic regression analysis, PTP was inversely associated with the CCVD risk after adjusting for age, sex, diabetes, hypertension, and dyslipidemia. A 10% increase in PTP reduced CCVD risk by 0.96 (95% confidence interval 0.93 to 0.99). Reduced CCVD risk was robust for both conventional antipsoriatic therapy and biologics. Our study found that systemic antipsoriatic therapy use was inversely associated with CCVD risk in psoriasis patients. These findings suggested that systemic antipsoriatic therapy could reduce CCVD development in patients with psoriasis.

Automated Mass Screening for Comorbidities of Vitiligo Using the National Health Insurance Database

Although the study design for identifying specific disease associations using a health insurance database has been well-established, few studies explore unknown comorbidities. We conducted a series of automated case-control studies for all International Classification of Disease, Tenth Revision, Clinical Modification diagnostic codes (A01-Z99) using the Korean National Health Insurance database from 2007 to 2017 to reveal undiscovered disease associations of vitiligo. A total of 90,297 patients with vitiligo and 90,297 age- and sex-matched controls without vitiligo were included, and disease associations for 1,265 relevant diagnostic codes were screened. A meta-analysis of the individual ORs for each International Classification of Disease, Tenth Revision code was performed to identify the possibility of selection bias. Finally, the association with vitiligo was significantly increased in 45 diseases and decreased in 6 diseases. We not only reaffirmed the positive correlation between vitiligo and other autoimmune diseases but also observed associations with obsessive-compulsive disorder and melanoma. In contrast, femur fracture showed a negative correlation. In this study, we attempted an automated mass screening and suggested a possible selection bias. In the era of large-scale databases, a systematic and comprehensive approach might be needed.

The effect of daily UVA phototherapy for 2 weeks on clinic and 24-h blood pressure in individuals with mild hypertension

Latitude and season determine exposure to ultraviolet radiation and correlate with population blood pressure. Evidence for Vitamin D causing this relationship is inconsistent, and temperature changes are only partly responsible for BP variation. In healthy individuals, a single irradiation with 20 J/cm² UVA mobilises NO from cutaneous stores to the circulation, causes arterial vasodilatation, and elicits a transient fall in BP. We, therefore, tested whether low-dose daily UVA phototherapy might be an effective treatment for mild hypertension. 13 patients with untreated high-normal or stage 1 hypertension (BP 130-159/85-99 mm Hg), confirmed by 24-h ambulatory blood pressure (ABP), were recruited. Using home phototherapy lamps they were either exposed to 5 J/cm² full body UVA (320-410 nm) radiation each day for 14 days, or sham-irradiated with lamps filtered to exclude wavelengths <500 nm. After a washout period of 3 ± 1 week, the alternate irradiation was delivered. 24-h ABP was measured on day 0 before either irradiation sequence and on day 14. Clinic BP was recorded on day 0, and within 90 min of irradiation on day 14. There was no effect on 24-h ABP following UVA irradiation. Clinic BP shortly after irradiation fell with UVA (-8.0 ± 2.9/-3.8 ± 1.1 mm Hg p = 0.034/0.029) but not sham irradiation (1.1 ± 3.0/0.9 ± 1.5 mm Hg). Once daily low-dose UVA does not control mildly elevated BP although it produces a transient fall shortly after irradiation. More frequent exposure to UVA might be effective. Alternatively, UVB, which photo-releases more NO from skin, could be tried.

Association of sunshine duration with acute myocardial infarction hospital admissions in Beijing, China: A time-series analysis within-summer

BACKGROUND

Over the years, various epidemiological studies found that acute myocardial infarction (AMI) often shows seasonal rhythm patterning, which is usually influenced by the variations of environmental factors, such as air pollution, ambient temperature, solar activity, relative humidity. However, there are few studies on the impact of sunlight-induced AMI especially in developing countries, and they had inconsistent results. This study aimed to examine within-summer variations in the temporal association between sun exposure and AMI.

METHODS

We obtained hospitalization data for AMI of Beijing during 2013-2019. We used a distributed lag non-linear model (DLNM) combined with a quasi-Poisson regression model to estimate the non-linear lag effects of sunshine duration on AMI incidences. We evaluated the overall effect of AMI admissions with exposure to sunshine duration in the lag 0-21 days.

RESULTS

A total of 45,301 AMI cases were enrolled in our study during summer (June-September). The minimum of the morbidity was during days with a sunshine duration of 3.9 h. We found significant and U-shaped associations between sunshine duration and AMI, and the overall estimated relative risk was 1.29 (95% CI: 1.02,1.62) and 1.69 (95% CI: 1.28,2.24) for short (1st percentile) and long (99th percentile) sunshine duration, respectively. The males and younger people (<65 years) were most susceptible to these effects.

CONCLUSION

Our results suggest that both short and long sunshine duration could increase the risk of AMI admissions, especially for males and younger people. We suggest that public health policymakers should fully consider the balance of the pros and cons of solar exposure, and provide appropriate public health recommendations accordingly to gain the greatest benefits from sunlight.

Vitiligo and Metabolic Syndrome: Systematic Review and Meta-Analysis

BACKGROUND

Metabolic syndrome (MetS) has been associated with various skin conditions including vitiligo. However, the association between these 2 conditions has yet to be determined by quantitative meta-analysis.

OBJECTIVE

The aim of this paper was to determine the association between vitiligo and metabolic syndrome via systematic review and meta-analysis.

METHODS

A systematic literature search of Pubmed, Embase, Cochrane, and Web of Science was performed for all published literature prior to August 16, 2020. Case control and prospective cross-sectional studies analyzing the association between vitiligo and MetS were included in this review. The primary outcome measures include the type of vitiligo, diagnostic criteria for MetS, components of MetS (waist circumference, blood pressure, triglycerides, fasting glycemic index, and high-density lipoprotein cholesterol), low-density lipoprotein cholesterol levels, and BMI. A meta-analysis was performed to evaluate the prevalence and association of MetS in patients with vitiligo.

RESULTS

A total of 6 studies (n=734 participants) meeting eligibility criteria were included for systematic review and meta-analysis. The pooled prevalence of MetS in patients with vitiligo was (0.296, 95% CI 0.206, 0.386; P<.001). Patients with vitiligo were no more likely to develop MetS compared to control patients (odds ratio 1.66, 95% CI 0.83, 3.33; P=.01). A leave-one-out sensitivity analysis showed a significant association between MetS and vitiligo (P<.001). Significant elevations in fasting glycemic index (mean difference 5.35, 95% CI 2.77, 7.93; P<.001) and diastolic blood pressure (mean difference 1.97, 95% CI 0.02, 3.92; P=.05) were observed in patients with vitiligo compared to control patients.

CONCLUSIONS

The association between vitiligo and metabolic syndrome carries important clinical implications. Dermatologists and other multidisciplinary team members should remain vigilant when treating this patient population in order to prevent serious cardiovascular complications that may arise as a result of metabolic disease.

Cardiovascular Disease-Associated Skin Conditions

According to data from the American Heart Association and the World Health Organization, cardiovascular disease (CVD) is the most frequent cause of premature death. Several inflammatory and non-inflammatory skin diseases have been associated with metabolic syndrome and cardiovascular risk (CVR). Here, we classified these conditions into traditionally CVR-associated and those that have been linked to a lesser degree. Psoriasis and hidradenitis suppurativa are commonly associated with CVD, sharing common inflammatory pathways and a higher prevalence of traditional cardiovascular risk factors. Many other diseases could be associated indirectly – with no common pathogenic features with the atheromatous disease – but share a higher prevalence of standard cardiovascular risk and chronic inflammatory state. This review aims to highlight the associated cardiovascular risk that exists for some dermatologic diseases and sensitize cardiologists, dermatologists, and first care providers to implement risk factor control promptly.

Investigating the Potential for Ultraviolet Light to Modulate Morbidity and Mortality From COVID-19: A Narrative Review and Update

During the COVID-19 (coronavirus disease of 2019) pandemic, researchers have been seeking low-cost and accessible means of providing protection from its harms, particularly for at-risk individuals such as those with cardiovascular disease, diabetes and obesity. One possible way is via safe sun exposure, and/or dietary supplementation with induced beneficial mediators (e.g., vitamin D). In this narrative review, we provide rationale and updated evidence on the potential benefits and harms of sun exposure and ultraviolet (UV) light that may impact COVID-19. We review recent studies that provide new evidence for any benefits (or otherwise) of UV light, sun exposure, and the induced mediators, vitamin D and nitric oxide, and their potential to modulate morbidity and mortality induced by infection with SARS-CoV-2 (severe acute respiratory disease coronavirus-2). We identified substantial interest in this research area, with many commentaries and reviews already published; however, most of these have focused on vitamin D, with less consideration of UV light (or sun exposure) or other mediators such as nitric oxide. Data collected to-date suggest that ambient levels of both UVA and UVB may be beneficial for reducing severity or mortality due to COVID-19, with some inconsistent findings. Currently unresolved are the nature of the associations between blood 25-hydroxyvitamin D and COVID-19 measures, with more prospective data needed that better consider lifestyle factors, such as physical activity and personal sun exposure levels. Another short-coming has been a lack of measurement of sun exposure, and its potential to influence COVID-19 outcomes. We also discuss possible mechanisms by which sun exposure, UV light and induced mediators could affect COVID-19 morbidity and mortality, by focusing on likely effects on viral pathogenesis, immunity and inflammation, and potential cardiometabolic protective mechanisms. Finally, we explore potential issues including the impacts of exposure to high dose UV radiation on COVID-19 and vaccination, and effective and safe doses for vitamin D supplementation.