Seasonal variations of U.S. mortality rates: Roles of solar ultraviolet-B doses, vitamin D, gene exp ression, and infections

Vitamin D: Evidence-Based Health Benefits and Recommendations for Population Guidelines

Vitamin D offers numerous under-recognized health benefits beyond its well-known role in musculoskeletal health. It is vital for extra-renal tissues, prenatal health, brain function, immunity, pregnancy, cancer prevention, and cardiovascular health. Existing guidelines issued by governmental and health organizations are bone-centric and largely overlook the abovementioned extra-skeletal benefits and optimal thresholds for vitamin D. In addition, they rely on randomized controlled trials (RCTs), which seldom show benefits due to high baseline 25-hydroxyvitamin D [25(OH)D] concentrations, moderate supplementation doses, and flawed study designs. This review emphasizes the findings from prospective cohort studies showing that higher 25(OH)D concentrations reduce the risks of major diseases and mortality, including pregnancy and birth outcomes. Serum concentrations > 30 ng/mL (75 nmol/L) significantly lower disease and mortality risks compared to <20 ng/mL. With 25% of the U.S. population and 60% of Central Europeans having levels <20 ng/mL, concentrations should be raised above 30 ng/mL. This is achievable through daily supplementation with 2000 IU/day (50 mcg/day) of vitamin D3, which prevent diseases and deaths. Furthermore, a daily dose between 4000 and 6000 IU of vitamin D3 to achieve serum 25(OH)D levels between 40 and 70 ng/mL would provide greater protection against many adverse health outcomes. Future guidelines and recommendations should integrate the findings from observational prospective cohort studies and well-designed RCTs to improve public health and personalized care.

Assessment of Vitamin D Status in the Drâa-Tafilalet Population (Morocco) Based on Sociodemographic, Health, and Nutritional Factors

The purpose of this study was to evaluate the vitamin D status and determine the factors influencing it in the Drâa-Tafilalet community (southeastern Morocco). Sociodemographic factors, health, cognitive status, sun exposure, and nutritional conditions were examined to help us understand their association with vitamin D status. Vitamin D data were gathered through laboratory testing, while demographic and health information was collected through interviews with participants in 2023. The study involved 100 participants aged 60 and above, most of whom were women (85%) rather than men (15%). The majority of participants were Arabs (90%), with a minority being Amazigh (10%). The average vitamin D level was 31.83 ± 10.55 ng/mL, varying based on participants' age, education, and gender. Sun-exposed individuals exhibited significantly higher mean vitamin D levels (33.56 ± 11.99 ng/mL) compared to those with limited sun exposure (28.97 ± 9.28 ng/mL). Moreover, the time spent outdoors, seasonal changes, and the duration of sun exposure affected the levels of vitamin D. These findings depict the vitamin D status of the elderly population of Drâa-Tafilalet, recognized as one of Morocco's poorest regions, shedding light on the significant influencers. Nonetheless, additional research is necessary to explore the correlation between dietary habits, sunlight exposure, and vitamin D levels in both young and elderly populations.

Low vitamin D levels are linked with increased cardiovascular disease risk in young adults: a sub-study and secondary analyses from the ACTIBATE randomized controlled trial

PURPOSE

Vitamin D deficiency is related to metabolic disturbances. Indeed, a poor vitamin D status has been usually detected in patients with cardiovascular disease (CVD). However, the relationship between vitamin D and CVD risk factors in young adults remains controversial at present. This study aimed to examine the association between circulating 25-hydroxivitamin D (25(OH)D) and CVD risk factors in young adults.

METHODS

The present cross-sectional study included a cohort of 177 young adults aged 18-25 years old (65% women). 25(OH)D serum concentrations were assessed using a competitive chemiluminescence immunoassay. Fasting CVD risk factors (i.e., body composition, blood pressure, glucose metabolism, lipid profile, liver, and inflammatory markers) were determined by routine methods. A panel of 63 oxylipins and endocannabinoids (eCBs) was also analyzed by targeted metabolomics.

RESULTS

Circulating 25(OH)D concentrations were inversely associated with a wide range of CVD risk factors including anthropometrical (all P ≤ 0.005), body composition (all P ≤ 0.038), glucose metabolism (all P ≤ 0.029), lipid profile (all P < 0.035), liver (all P ≤ 0.011), and pro-inflammatory biomarkers (all P ≤ 0.030). No associations of serum 25(OH)D concentrations were found with pro-inflammatory markers (all P ≥ 0.104), omega-6 and omega-3 oxylipins, nor eCBs concentrations or their analogs (all P ≥ 0.05).

CONCLUSION

The present findings support the idea that 25(OH)D could be a useful predictor of CVD risk in young individuals.

The Power of Vitamin D: Is the Future in Precision Nutrition through Personalized Supplementation Plans?

In the last few decades, vitamin D has undeniably been one of the most studied nutrients. Despite our ability to produce vitamin D through sunlight exposure, its presence in several natural food sources and fortified foods, and its widespread availability as a dietary supplement, vitamin D deficiency is a serious public health problem, affecting nearly 50% of the global population. Low serum levels of vitamin D are being associated with increased susceptibility to numerous health conditions, including respiratory infections, mental health, autoimmune diseases, and different cancer types. Although the association between vitamin D status and health is well-established, the exact beneficial effects of vitamin D are still inconclusive and indefinite, especially when considering the prevention and treatment of different health conditions and the determination of an appropriate dosage to exert those beneficial effects in various population groups. Therefore, further research is needed. With constant improvements in our understanding of individual variations in vitamin D metabolism and requirements, in the future, precision nutrition and personalized supplementation plans could prove beneficial.

Association Between Nutrients and Cardiovascular Diseases

Cardiovascular diseases (CVD) constitute a leading cause of global mortality. Inflammation and oxidative stress are key molecular underpinnings of CVD pathogenesis. This comprehensive review explores the multifaceted role of nutrients in cardiovascular health beyond their impact on cardiac events. The manuscript examines the influence of macronutrients such as fats and carbohydrates, as well as micronutrients including vitamins and folate, on CVD. Additionally, the interplay between dietary supplements and CVD risk reduction is investigated. The purpose of this manuscript is to provide a comprehensive overview of the diverse mechanisms through which nutrients contribute to cardiovascular well-being, addressing both cardioprotective effects and their broader implications. Through an analysis of pertinent studies, we illuminate the complex relationship between nutrition, lifestyle, and cardiovascular health, underscoring the significance of a holistic approach to CVD prevention and management.

Periodontal Disease and Other Adverse Health Outcomes Share Risk Factors, including Dietary Factors and Vitamin D Status

For nearly a century, researchers have associated periodontal disease (PD) with risks of other adverse health outcomes such as cardiovascular disease, diabetes mellitus, and respiratory diseases, as well as adverse pregnancy outcomes. Those findings have led to the hypothesis that PD causes those adverse health outcomes either by increasing systemic inflammation or by the action of periodontopathic bacteria. However, experiments largely failed to support that hypothesis. Instead, the association is casual, not causal, and is due to shared underlying modifiable risk factors, including smoking, diet, obesity, low levels of physical activity, and low vitamin D status. Diabetes mellitus is also considered a risk factor for PD, whereas red and processed meat are the most important dietary risk factors for diabetes. Because PD generally develops before other adverse health outcomes, a diagnosis of PD can alert patients that they could reduce the risk of adverse health outcomes with lifestyle changes. In addition, type 2 diabetes mellitus can often be reversed rapidly by adopting an anti-inflammatory, nonhyperinsulinemic diet that emphasizes healthful, whole plant-based foods. This review describes the evidence that proinflammatory and prohyperinsulinemia diets and low vitamin D status are important risk factors for PD and other adverse health outcomes. We also make recommendations regarding dietary patterns, food groups, and serum 25-hydroxyvitamin D concentrations. Oral health professionals should routinely inform patients with PD that they could reduce their risk of severe PD as well as the risks of many other adverse health outcomes by making appropriate lifestyle changes.

Guidelines for Preventing and Treating Vitamin D Deficiency: A 2023 Update in Poland

Introduction: All epidemiological studies suggest that vitamin D deficiency is prevalent among the Polish general population. Since vitamin D deficiency was shown to be among the risk factors for many diseases and for all-cause mortality, concern about this problem led us to update the previous Polish recommendations. Methods: After reviewing the epidemiological evidence, case-control studies and randomized control trials (RCTs), a Polish multidisciplinary group formulated questions on the recommendations for prophylaxis and treatment of vitamin D deficiency both for the general population and for the risk groups of patients. The scientific evidence of pleiotropic effects of vitamin D as well as the results of panelists' voting were reviewed and discussed. Thirty-four authors representing different areas of expertise prepared position statements. The consensus group, representing eight Polish/international medical societies and eight national specialist consultants, prepared the final Polish recommendations. Results: Based on networking discussions, the ranges of total serum 25-hydroxyvitamin D concentration indicating vitamin D deficiency [<20 ng/mL (<50 nmol/L)], suboptimal status [20-30 ng/mL (50-75 nmol/L)], and optimal concentration [30-50 ng/mL (75-125 nmol/L)] were confirmed. Practical guidelines for cholecalciferol (vitamin D3) as the first choice for prophylaxis and treatment of vitamin D deficiency were developed. Calcifediol dosing as the second choice for preventing and treating vitamin D deficiency was introduced. Conclusions: Improving the vitamin D status of the general population and treatment of risk groups of patients must be again announced as healthcare policy to reduce a risk of spectrum of diseases. This paper offers consensus statements on prophylaxis and treatment strategies for vitamin D deficiency in Poland.

Confounding Effect of Undergraduate Semester-Driven "Academic" Internet Searches on the Ability to Detect True Disease Seasonality in Google Trends Data: Fourier Filter Method Development and Demonstration

Background

Internet search volume for medical information, as tracked by Google Trends, has been used to demonstrate unexpected seasonality in the symptom burden of a variety of medical conditions. However, when more technical medical language is used (eg, diagnoses), we believe that this technique is confounded by the cyclic, school year-driven internet search patterns of health care students.

Objective

This study aimed to (1) demonstrate that artificial "academic cycling" of Google Trends' search volume is present in many health care terms, (2) demonstrate how signal processing techniques can be used to filter academic cycling out of Google Trends data, and (3) apply this filtering technique to some clinically relevant examples.

Methods

We obtained the Google Trends search volume data for a variety of academic terms demonstrating strong academic cycling and used a Fourier analysis technique to (1) identify the frequency domain fingerprint of this modulating pattern in one particularly strong example, and (2) filter that pattern out of the original data. After this illustrative example, we then applied the same filtering technique to internet searches for information on 3 medical conditions believed to have true seasonal modulation (myocardial infarction, hypertension, and depression), and all bacterial genus terms within a common medical microbiology textbook.

Results

Academic cycling explains much of the seasonal variation in internet search volume for many technically oriented search terms, including the bacterial genus term ["Staphylococcus"], for which academic cycling explained 73.8% of the variability in search volume (using the squared Spearman rank correlation coefficient, P<.001). Of the 56 bacterial genus terms examined, 6 displayed sufficiently strong seasonality to warrant further examination post filtering. This included (1) ["Aeromonas" + "Plesiomonas"] (nosocomial infections that were searched for more frequently during the summer), (2) ["Ehrlichia"] (a tick-borne pathogen that was searched for more frequently during late spring), (3) ["Moraxella"] and ["Haemophilus"] (respiratory infections that were searched for more frequently during late winter), (4) ["Legionella"] (searched for more frequently during midsummer), and (5) ["Vibrio"] (which spiked for 2 months during midsummer). The terms ["myocardial infarction"] and ["hypertension"] lacked any obvious seasonal cycling after filtering, whereas ["depression"] maintained an annual cycling pattern.

Conclusions

Although it is reasonable to search for seasonal modulation of medical conditions using Google Trends' internet search volume and lay-appropriate search terms, the variation in more technical search terms may be driven by health care students whose search frequency varies with the academic school year. When this is the case, using Fourier analysis to filter out academic cycling is a potential means to establish whether additional seasonality is present.

An Exploration of How Solar Radiation Affects the Seasonal Variation of Human Mortality Rates and the Seasonal Variation in Some Other Common Disorders

Many diseases have large seasonal variations in which winter overall mortality rates are about 25% higher than in summer in mid-latitude countries, with cardiovascular diseases and respiratory infections and conditions accounting for most of the variation. Cancers, by contrast, do not usually have pronounced seasonal variations in incidence or mortality rates. This narrative review examines the epidemiological evidence for seasonal variations in blood pressure, cardiovascular disease rates and respiratory viral infections in relation to atmospheric temperature and humidity, and solar UV exposure through vitamin D production and increased blood concentrations of nitric oxide. However, additional mechanisms most likely exist by which solar radiation reduces the risk of seasonally varying diseases. Some studies have been reported with respect to temperature without considering solar UV doses, although studies regarding solar UV doses, such as for respiratory infections, often consider whether temperature can affect the findings. More research is indicated to evaluate the relative effects of temperature and sun exposure on the seasonality of mortality rates for several diseases. Since solar ultraviolet-B (UVB) doses decrease to vanishingly small values at higher latitudes in winter, the use of safe UVB lamps for indoor use in winter may warrant consideration.

Unraveling racial disparities in asthma emergency department visits using electronic healthcare records and machine learning

OBJECTIVE

Hospital emergency department (ED) visits by asthmatics differ based on race and season. The objectives of this study were to investigate season- and race-specific disparities for asthma risk, and to identify environmental exposure variables associated with ED visits among more than 42,000 individuals of African American (AA) and European American (EA) descent identified through electronic health records (EHRs).

METHODS

We examined data from 42,375 individuals (AAs = 14,491, EAs = 27,884) identified in EHRs. We considered associated demographic (race, age, gender, insurance), clinical (smoking status, ED visits, FEV1%), and environmental exposures data (mold, pollen, and pollutants). Machine learning techniques, including random forest (RF), extreme gradient boosting (XGB), and decision tree (DT) were used to build and identify race- and -season-specific predictive models for asthma ED visits.

RESULTS

Significant differences in ED visits and FEV1% among AAs and EAs were identified. ED visits by AAs was 32.0% higher than EAs and AAs had 6.4% lower FEV1% value than EAs. XGB model was used to accurately classify asthma patients visiting ED into AAs and EAs. Pollen factor and pollution (PM2.5, PM10) were the key variables for asthma in AAs and EAs, respectively. Age and cigarette smoking increase asthma risk independent of seasons.

CONCLUSIONS

In this study, we observed racial and season-specific disparities between AAs and EAs asthmatics for ED visit and FEV1% severity, suggesting the need to address asthma disparities through key predictors including socio-economic status, particulate matter, and mold.

Burden of disease induced by public overexposure to solar ultraviolet radiation (SUVR) at the national and subnational levels in Iran, 2005-2019

Estimating the burden of diseases induced by overexposure to solar ultraviolet radiation (SUVR) can help to prioritize environmental health interventions. The age-sex specific and cause-specific mortality and disability-adjusted life years (DALYs) attributable to overexposure to SUVR at the national and subnational levels in Iran, 2005-2019 were estimated. The burden of disease induced by overexposure to SUVR was quantified in four steps as follows: (1) estimating exposure to SUVR, (2) estimating total incidences and deaths of target causes, (3) assessing population attributable fractions of the target causes for the SUVR, and (4) calculating the attributable burden of disease. The attributable DALYs, deaths, age-standardized DALY rate, and age-standardized death rate at the national level were determined to be respectively 21896, 252, 42.59, and 0.56 in 2005 and were respectively changed to 28665, 377, 38.76, and 0.53 in 2019. The contributions of causes in the attributable DALYs at the national level were different by year and sex and for both sexes in 2019 were as follows: 46.15% for cataract, 20.36% for malignant skin melanoma, 16.07% for sunburn, 12.41% for squamous-cell carcinoma, and 5.01% for the other five causes. The contributions of population growth, population ageing, risk exposure, and risk-deleted DALY rate in the temporal variations of the attributable burden of disease in the country were +20.73%, +20.68%, +2.01%, and -12.51%. The highest and lowest provincial attributable age-standardized DALY rates in 2019 were observed in Fars (46.8) and Ardebil (32.7), respectively. The burden of disease induced by exposure to SUVR caused relatively low geographical inequality in health status in Iran. Due to increasing trends of the SUVR as well as the attributable burden of disease, the preventive interventions against the SUVR overexposure should be considered in the public health action plan all across the country.

National and subnational burden of disease attributable to occupational exposure to solar ultraviolet radiation (SUVR) in Iran, 2005-2019

Overexposure to solar ultraviolet radiation (SUVR) can cause skin and eye adverse effects for outdoor workers. In this study, the burden of disease induced by occupational exposure to SUVR and its spatiotemporal trend at national and sub-national levels in Iran, 2005-2019 were assessed. The attributable burden of disease was assessed using the following five datasets: (1) distribution of occupational exposure to SUVR, (2) total incidences and deaths of health outcomes of SUVR exposure, (3) population attributable fractions of the health outcomes of SUVR exposure, (4) age-gender distribution of outdoor workers, and (5) disability-adjusted life year (DALY) calculation constants. During 2005-2019, the attributable DALYs increased from 2442 to 2907 and the attributable DALY rate (per 100,000 workers) slightly decreased from 11.94 to 11.91. The share of YLL in the attributable burden of disease was in the range of 43%-46%. Out of nine causes, about 90% of the attributable burden of disease in 2019 was related to cataracts (29.9%), malignant skin melanoma (27.4%), squamous-cell carcinoma (18.6%), and sunburn (17.2%). During the study period, the attributable DALY rate in women increased by 60.95% (from 5.04 to 8.11) and in men decreased by 2.06% (from 13.03 to 12.76). The total attributable DALYs and DALY rate rose by age during 2005-2019. The contributions of population growth, risk-deleted DALY rates, exposure risk, and population age structure in temporal changes of the attributable burden of disease were 19.27%, 9.13%, -1.35%, and -14.8%, respectively. The three highest attributable DALY rates in 2019 were observed in South Khorasan (21.28), Chahar Mahal and Bakhtiari (17.42), and Kordestan (17.26), respectively. The preventive interventions against SUVR overexposure, regular screenings, and early treatments with an emphasis on occupations with continuous sun exposure and provinces with increasing attributable DALY rates should be considered in the occupational health action plan in the country.

Spatiotemporal analysis of solar ultraviolet radiation based on Ozone Monitoring Instrument dataset in Iran, 2005-2019

The solar ultraviolet radiation (UVR) at national, provincial and county levels in Iran during 2005-2019 were determined based on Ozone Monitoring Instrument (OMI) dataset. The temporal (annual and monthly) trends and spatial distributions of the UVR in terms of erythemally weighted daily dose (EDD), erythemally weighted irradiance at local solar noon time (EDR), and UV index and the major factors influencing the spatiotemporal trends were analyzed. The population-weighted average values of EDD, EDR, and UV index in Iran were respectively 3631 J/m², 176.3 mW/m², 7.1 in 2005 and rose by 0.22% per year to 3744 J/m², 181.7 mW/m², and 7.3, respectively in 2019, but the annual trend was not statistically significant. The EDD in Iran during the study period exhibited the highest monthly average value in June (6339 J/m²) and the lowest one in December (1263 J/m²). The solar UVA/UVB ratios at the national level during 2005-2019 were considerably lower in summer. The EDD provincial average values in the study period were in the range of 2717 (Gilan) to 4424 J/m² (Fars). The spatiotemporal variations of the solar UVR parameters were well described by the linear models as a function of cloud optical thickness (COT), ozone column amount, surface albedo, latitude, and altitude (R² > 0.961, p value < 0.001) and the temporal changes of the solar UVR parameters were mainly caused by the COT. The results indicated that non-burning exposure to solar UVR in summer can be more efficient for vitamin D synthesis due to higher contribution of UVB in the solar UVR. The spatial distributions and temporal trends should be considered to determine the optimal duration, time and condition of exposure to the solar UVR for the public and occupational training and public health measures.

Vitamin D Status and Physical Activity during Wintertime in Forensic Inpatients-A Randomized Clinical Trial

This study aimed to gain deeper knowledge about the relationship between vitamin D and physical activity in a sample of forensic inpatients. Sixty-seven male forensic inpatients participated. Participants were randomly assigned into an Intervention group (vitamin D) or a Control group (placebo). The Physical Activity–Rating (PA-R) questionnaire was used to measure physical activity from January to May. Vitamin D status was measured as 25-hydroxy vitamin D (25-OHD) pre- and post-intervention. The results revealed that vitamin D status at post-test was positively correlated with physical activity, but there was no effect of vitamin D supplementation looking at the two randomized groups. However, controlling for body mass index (BMI), the results showed an effect of BMI and a main effect of groups with a higher level of physical activity in the Intervention group. No interaction effects were found. Participants were also assigned into High and Low vitamin D groups based on the vitamin D status at post-test; i.e., the upper (75.1 nmol/L) and lower quartile (46.7 nmol/L). T-tests revealed that participants with a vitamin D status above 75 nmol/L showed significantly higher levels of physical activity than participants with a vitamin D status below 46.7 nmol/L. Thus, a vitamin D status above 75 nmol/L seems to be an optimal level.

The Impact of Vitamin D on Skin Aging

The active metabolites of vitamin D₃ (D₃) and lumisterol (L₃) exert a variety of antiaging and photoprotective effects on the skin. These are achieved through immunomodulation and include anti-inflammatory actions, regulation of keratinocytes proliferation, and differentiation programs to build the epidermal barrier necessary for maintaining skin homeostasis. In addition, they induce antioxidative responses, inhibit DNA damage and induce DNA repair mechanisms to attenuate premature skin aging and cancerogenesis. The mechanism of action would involve interaction with multiple nuclear receptors including VDR, AhR, LXR, reverse agonism on RORα and -γ, and nongenomic actions through 1,25D₃-MARRS receptor and interaction with the nongenomic binding site of the VDR. Therefore, active forms of vitamin D₃ including its canonical (1,25(OH)₂D₃) and noncanonical (CYP11A1-intitated) D₃ derivatives as well as L₃ derivatives are promising agents for the prevention, attenuation, or treatment of premature skin aging. They could be administrated orally and/or topically. Other forms of parenteral application of vitamin D₃ precursor should be considered to avoid its predominant metabolism to 25(OH)D₃ that is not recognized by CYP11A1 enzyme. The efficacy of topically applied vitamin D₃ and L₃ derivatives needs further clinical evaluation in future trials.

Association Between Vitamin D Deficiency and COVID-19 Incidence, Complications, and Mortality in 46 Countries: An Ecological Study

Each patient's immune defenses play a major role in mitigating the impact (ie, morbidity and mortality) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19). Vitamin D is an important modulator of the immune system. Although serum 25-hydroxyvitamin D levels can be raised through diet or supplements, most vitamin D in the body is the result of dermal synthesis from ultraviolet radiation. The production of vitamin D in the skin, however, can be limited by latitude, skin-covering clothes, the use of sunblock, and skin pigmentation. Vitamin D deficiency affects a high percentage of the world population. Serum 25-hydroxyvitamin D levels are suboptimal, not only in specific risk groups but also in adults from many countries. Low vitamin D levels, therefore, represent a risk factor for several different pathologies, including SAR-CoV-2. This study used an ecological design to assess the association between vitamin D deficiency and COVID-19 incidence, complications, and mortality across 46 countries. All data were obtained from published sources. The results of the study suggest an association at the population level between the prevalence of vitamin D deficiency and the risk of being infected with COVID-19, severity of the disease, and risk of dying from it.

Intensified impacts on mortality due to compound winter extremes in the Czech Republic

Although impacts of extremely cold temperatures on human health have been widely studied, adverse effects of other extreme weather phenomena have so far received much less attention. We employed a high-quality long-term mortality time series (1982-2017) to evaluate impacts of extreme winter weather in the Czech Republic. We aimed to clarify whether compound events of extreme weather cause larger impacts on mortality than do each type of extreme if evaluated individually. Using daily data from the E-OBS and ERA5 datasets, we analyzed 9 types of extreme events: extreme wind gust, precipitation, snowfall, and sudden temperature and pressure changes. Relative mortality deviations from the adjusted baseline were used to estimate the immediate effect of the selected extreme events on excess mortality. The impact was adjusted for the effect of extreme cold. Extreme events associated with sudden rise of minimum temperature and pressure drops had generally significant impact on excess mortality (3.7% and 1.4% increase). The impacts were even more pronounced if these events occurred simultaneously or were compounded with other types of extremes, such as heavy precipitation, snowfall, maximum temperature rise, and their combinations (increase as great as 14.4%). Effects of some compound events were significant even for combinations of extremes having no significant impact on mortality when evaluated separately. On the other hand, a "protective" effect of pressure increases reduced the risk for its compound events. Meteorological patterns during extreme events linked to excess mortality indicate passage of a low-pressure system northerly from the study domain. We identified extreme winter weather events other than cold temperatures with significant impact on excess mortality. Our results suggest that occurrence of compound extreme events strengthen the impacts on mortality and therefore analysis of multiple meteorological parameters is a useful approach in defining adverse weather conditions.

Deep longitudinal multiomics profiling reveals two biological seasonal patterns in California

The influence of seasons on biological processes is poorly understood. In order to identify biological seasonal patterns based on diverse molecular data, rather than calendar dates, we performed a deep longitudinal multiomics profiling of 105 individuals over 4 years. Here, we report more than 1000 seasonal variations in omics analytes and clinical measures. The different molecules group into two major seasonal patterns which correlate with peaks in late spring and late fall/early winter in California. The two patterns are enriched for molecules involved in human biological processes such as inflammation, immunity, cardiovascular health, as well as neurological and psychiatric conditions. Lastly, we identify molecules and microbes that demonstrate different seasonal patterns in insulin sensitive and insulin resistant individuals. The results of our study have important implications in healthcare and highlight the value of considering seasonality when assessing population wide health risk and management.

Plasma 25-Hydroxyvitamin D Levels and VDR Gene Expression in Peripheral Blood Mononuclear Cells of Leukemia Patients and Healthy Subjects in Central Kazakhstan

Low blood levels of the vitamin D metabolite 25-hydroxyvitamin D [25(OH)D] have been associated with an increased risk and poorer outcomes of various cancers, including hematological malignancies. The Central Kazakhstan area has a relatively high incidence rate of leukemia. However, the relationship between vitamin D status and leukemia or other types of cancer in Kazakhstan has not yet been addressed. Therefore, in this first pilot single-center study conducted in Central Kazakhstan, we compared plasma levels of 25(OH)D and the vitamin D receptor (VDR) gene expression levels in peripheral blood mononuclear cells of patients with leukemia and demographically matching healthy volunteers. The levels of 25(OH)D in patients were found to be significantly lower (10.8 ± 7.0 ng/mL; n = 31) than in healthy subjects (21.6 ± 7.8 ng/mL; n = 34; p < 0.0001). A similar difference was observed in both younger (<60 years old) and older (>60 years old) participants, though there was no association between 25(OH)D concentration and age within the patient group. In female patients, 25(OH)D levels were significantly lower than in male patients (p = 0.04). No significant seasonal variations of 25(OH)D were observed in either the patient or the control group. VDR gene expression levels appeared to be similar in leukemia patients and healthy subjects, and no correlation between the cellular VDR expression and plasma 25(OH)D concentrations was observed in either group of participants. We did not observe a significant association of 25(OH)D or VDR levels and overall survival of leukemia patients. This observational study conducted for the first time in Kazakhstan supports previous findings demonstrating reduced blood 25(OH)D levels in cancer (leukemia) patients. Larger studies are required to determine whether low 25(OH)D plasma concentrations represent a risk factor for leukemia development and/or progression.

The effects of diet on levels of physical activity during winter in forensic inpatients - A randomized controlled trial

Background

Fish consumption has been shown to have beneficial effects on biological and subjective measures of health and well-being. However, little is known about the effects of fish consumption at the behavioral level.

Objective

The primary aim of this study was to investigate the influence of diet on behavior such as physical activity during winter in forensic inpatients. The secondary aim was to investigate the relationship between vitamin D status and physical activity.

Design

Eighty-one male forensic inpatients participated in this study. Participants were randomized into two different diet groups: a Fish group receiving fatty fish three times per week and a Control group receiving an alternative meal (e.g. chicken, pork, and beef); while the Fish group received their fish, the Control group received an alternate meal, but with the same nutritional value as their habitual diet. The duration of the food intervention was 6 months.

Results

The results revealed that the Fish group had a regular pattern of physical activity throughout the intervention period. The participants in the Control group showed a more irregular pattern of physical activity in addition to a significant reduction in physical activity over time.

Conclusion

Behavior such as physical activity during winter seemed to be influenced by the diet.

Targeted 25-hydroxyvitamin D concentration measurements and vitamin D3 supplementation can have important patient and public health benefits

Over the past two decades, many studies reported the benefits of higher 25-hydroxyvitamin D [25(OH)D] concentrations for nonskeletal effects. Researchers found significant benefits in reducing risk of acute respiratory tract infections, many types of cancer, type 2 diabetes mellitus, premature death, and adverse pregnancy and birth outcomes. In addition, 25(OH)D concentrations are low for various reasons in several categories of people, including the obese, those with dark skin living at higher latitudes, the elderly, and those who do not eat much eggs, fish, meat, or vitamin D fortified milk. Measuring 25(OH)D concentrations is one way to both increase the awareness of vitamin D's importance in maintaining good health and to encourage vitamin D supplementation or increased solar ultraviolet-B exposure to sustain well-being throughout life by reducing disease incidence. Although 20 ng/ml seems adequate to reduce risk of skeletal problems and acute respiratory tract infections, concentrations above 30 ng/ml have been associated with reduced risk of cancer, type 2 diabetes mellitus, and adverse pregnancy and birth outcomes. Thus, judicious testing of 25(OH)D concentrations could reduce disease incidence and make treatment expenditures more cost-effective.

The Role of Classical and Novel Forms of Vitamin D in the Pathogenesis and Progression of Nonmelanoma Skin Cancers

Nonmelanoma skin cancers including basal and squamous cell carcinomas (SCC and BCC) represent a significant clinical problem due to their relatively high incidence, imposing an economic burden to healthcare systems around the world. It is accepted that ultraviolet radiation (UVR: λ = 290-400 nm) plays a crucial role in the initiation and promotion of BCC and SCC with UVB (λ = 290-320 nm) having a central role in this process. On the other hand, UVB is required for vitamin D3 (D3) production in the skin, which supplies >90% of the body's requirement for this prohormone. Prolonged exposure to UVB can also generate tachysterol and lumisterol. Vitamin D3 itself and its canonical (1,25(OH)2D3) and noncanonical (CYP11A1-intitated) D3 hydroxyderivatives show photoprotective functions in the skin. These include regulation of keratinocyte proliferation and differentiation, induction of anti-oxidative responses, inhibition of DNA damage and induction of DNA repair mechanisms, and anti-inflammatory activities. Studies in animals have demonstrated that D3 hydroxyderivatives can attenuate UVB or chemically induced epidermal cancerogenesis and inhibit growth of SCC and BCC. Genomic and non-genomic mechanisms of action have been suggested. In addition, vitamin D3 itself inhibits hedgehog signaling pathways which have been implicated in many cancers. Silencing of the vitamin D receptor leads to increased propensity to develop UVB or chemically induced epidermal cancers. Other targets for vitamin D compounds include 1,25D3-MARRS, retinoic orphan receptors α and γ, aryl hydrocarbon receptor, and Wnt signaling. Most recently, photoprotective effects of lumisterol hydroxyderivatives have been identified. Clinical trials demonstrated a beneficial role of vitamin D compounds in the treatment of actinic keratosis. In summary, recent advances in vitamin D biology and pharmacology open new exciting opportunities in chemoprevention and treatment of skin cancers.

Linking the metabolic syndrome and obesity with vitamin D status: risks and opportunities for improving cardiometabolic health and well-being

The global death toll from noncommunicable diseases is exceptionally high, reported to cause 71% of global deaths worldwide. Metabolic syndrome risk factors, especially excessive adiposity and obesity, are at the heart of the problem resulting in increased co-morbidities such as cardiometabolic diseases and cancer, increased health costs, poorer quality of life, and shortened survival. Vitamin D3 can positively reverse many of these adverse effects and outcomes through blocking signaling mechanisms that predispose to cardiometabolic and metastatic disease. As an affordable natural agent, vitamin D3 can be used to counteract obesity-induced inflammation, block early adipogenesis, enhance glucose uptake, counteract hyperleptinemia, ameliorate insulin resistance, and reduce hypertension. This is supported by data from in vitro, in vivo and epidemiological studies and clinical trials. We propose that everyone in general and obese patients in particular consider raising 25-hydroxyvitamin D levels through UVB exposure and/or supplemental vitamin D3 intake to reduce cardiometabolic and metastatic disease and increase longevity.

Short-term exposure to ambient air pollution and daily atherosclerotic heart disease mortality in a cool climate

The associations between exposure to short-term ambient air pollution and daily atherosclerotic heart disease (ASHD) mortality in cool climate have not been established. We performed a time-series analysis in Shenyang, the largest city of Northeastern China. We identified 7659 ASHD deaths and obtained deaths, ambient air pollution levels, and meteorological data for Shenyang during 2014-2017. The impact of ambient air pollution on daily ASHD deaths was analyzed using generalized additive models (GAMs). Cumulative lag effects were investigated using distributed lag non-linear models (DLNM). We found ASHD deaths significantly increased during days with higher air pollution. Particulate matter with diameter < 2.5 μm (PM_2.5), PM₁₀, and sulfur dioxide (SO₂) were positively associated with ASHD deaths among the total population. Both single- and multi-pollutants models indicated that PM_2.5, PM₁₀, and sulfur dioxide (SO₂) were positively associated with the deaths of women with AHSD, whereas only SO₂ was significant in men. This suggests significant gender-based differences in the fatal effects of ambient air pollution. Up to 28 days of single-day lag effects were observed for PM_2.5 and PM₁₀ in women. The cumulative lag effects of PM_2.5 and PM₁₀ showed increasing trends in both men and women; however, exposure to higher pollutant concentrations did not necessarily translate to greater risks. The ERRs differences between women and men were larger in cold days than in hot days, suggesting that lower temperature may exacerbate the adverse effects of air pollution on vulnerable women.

Weather fluctuations: predictive factors in the prevalence of acute coronary syndrome

Background: Meteorological parameters and seasonal changes can play an important role in the occurrence of acute coronary syndrome (ACS). However, there is almost no evidence on a national level to suggest the associations between these variables and ACS in Iran. We aim to identify the meteorological parameters and seasonal changes in relationship to ACS.

Methods: This retrospective cross-sectional study was conducted between 03/19/2015 to 03/18/2016 and used documents and records of patients with ACS in Mazandaran ProvinceHeart Center, Iran. The following definitive diagnostic criteria for ACS were used: (1) existence of cardiac enzymes (CK or CK-MB) above the normal range; (2) Greater than 1 mm ST-segment elevation or depression; (3) abnormal Q waves; and (4) manifestation of troponin enzyme in the blood. Data were collected daily, such as temperature (Celsius) changes, wind speed and its direction, rainfall, daily evaporation rate; number of sunny days, and relative humidity were provided by the Meteorological Organization of Iran.

Results: A sample of 2,054 patients with ACS were recruited. The results indicated the highest ACS events from March to May. Generally, wind speed (18 PM) [IRR = 1.051 (95% CI: 1.019 to1.083), P=0.001], daily evaporation [IRR = 1.039 (95% CI: 1.003 to 1.077), P=0.032], daily maximum (P<0.001) and minimum (P=0.003) relative humidity was positively correlated withACS events. Also, negatively correlated variables were daily relative humidity (18 PM) [IRR =0.985 (95% CI: 0.978 to 0.992), P<0.001], and daily minimum temperature [IRR = 0.942 (95%CI: 0.927 to 0.958), P<0.001].

Conclusion: Climate changes were found to be significantly associated with ACS; especially from cold weather to hot weather in March, April and May. Further research is needed to fully understand the specific conditions and cold exposures.

The Prevalence of Vitamin D Deficiency and the Determinants of 25(OH)D Concentration in Older Irish Adults: Data From The Irish Longitudinal Study on Ageing (TILDA)

Background

Few data are available examining the determinants of vitamin D status exclusively in older adults. We aimed to investigate the prevalence and determinants of vitamin D deficiency in a representative sample of the older Irish population (aged 50-98 years).

Methods

The concentration of 25-hydroxyvitamin D (25(OH)D) was measured in 5,356 community-dwelling older Irish adults from The Irish Longitudinal Study on Ageing (TILDA). Detailed demographic, geographic, lifestyle, and socioeconomic factors were assessed by questionnaire. Proportions of deficiency prevalence were generated by season sampled. Linear regression was used to investigate the association between 25(OH)D concentration and reported risk factors.

Results

The prevalence of deficiency (25(OH)D < 30 nmol/L) was 13.1% (95% CI: 12.1-14.2). Deficiency status was more prevalent in nonsupplement users, in winter, in smokers, in obese adults, the physically inactive, those living alone, and in the oldest old (>80 years). The main predictors (p < .05) of 25(OH)D concentration were supplement use (coefficient nmol/L: 27.2 [95% CI: 15.3-39.2]), smoking (-8.9 [-12.6--5.2]), summer season (5.9 [2.7-9.1]), and obesity (-4.0 [-6.3--1.7]).

Conclusion

Vitamin D deficiency is common among older Irish adults. These data indicate the need for targeted strategies within sections of the older population to improve vitamin D status.

Seasonal variation in mortality secondary to acute myocardial infarction in England and Wales: a secondary data analysis

BACKGROUND

Acute myocardial infarction (AMI) is a leading cause of death globally. Increase in AMI mortality during winter has also been identified in existing literature. This has been associated with low outdoor and indoor temperatures and increasing age. The relationship between AMI and other factors such as gender and socioeconomic factors varies from study to study. Influenza epidemics have also been identified as a contributory factor.

OBJECTIVE

This paper aims to illustrate the seasonal trend in mortality due to AMI in England and Wales with emphasis on excess winter mortality (EWM).

METHODS

Monthly mortality rates per 10 000 population were calculated from data provided by the UK Office for National Statistics (ONS) for 1997-2005. To quantify the seasonal variation in winter, the EWM estimates (EWM, EWM ratio, Excess Winter Mortality Index) for each year were calculated. Negative binomial regression model was used to estimate the relationship between increasing age and EWM.

RESULTS

The decline in mortality rate for AMI was 6.8% yearly between August 1997 and July 2005. Significant trend for reduction in AMI-associated mortality was observed over the period (p<0.001). This decline was not seen with EWM (p<0.001). 17% excess deaths were observed during winter. This amounted to about 20 000 deaths over the 8-year period. Increasing winter mortality was seen with increasing age for AMI.

CONCLUSION

EWM secondary to AMI does occur in England and Wales. Excess winter deaths due to AMI have remained high despite decline in overall mortality. More research is needed to identify the relationship of sex, temperature, acclimatisation, vitamin D and excess winter deaths due to AMI.

Maternal Vitamin D Status and the Relationship with Neonatal Anthropometric and Childhood Neurodevelopmental Outcomes: Results from the Seychelles Child Development Nutrition Study

Vitamin D has an important role in early life; however, the optimal vitamin D status during pregnancy is currently unclear. There have been recent calls for pregnant women to maintain circulating 25-hydroxyvitamin D (25(OH)D) concentrations >100 nmol/L for health, yet little is known about the long-term potential benefits or safety of achieving such high maternal 25(OH)D concentrations for infant or child health outcomes. We examined maternal vitamin D status and its associations with infant anthropometric and later childhood neurocognitive outcomes in a mother-child cohort in a sun-rich country near the equator (4.6° S). This study was conducted in pregnant mothers originally recruited to the Seychelles Child Development Nutrition Study. Blood samples (n = 202) taken at delivery were analysed for serum 25-hydroxyvitamin D (25(OH)D) concentrations. Multiple linear regression models assessed associations between maternal 25(OH)D and birth weight, infant head circumference, and neurocognitive outcomes in the children at age 5 years. Mothers were, on average, 27 years of age, and the children’s average gestational age was 39 weeks. None of the women reported any intake of vitamin D supplements. Maternal 25(OH)D concentrations had a mean of 101 (range 34–218 nmol/L) and none were deficient (<30 nmol/L). Maternal 25(OH)D concentrations were not associated with child anthropometric or neurodevelopmental outcomes. These findings appear to indicate that a higher vitamin D status is not a limiting factor for neonatal growth or neurocognitive development in the first 5 years of life. Larger studies with greater variability in vitamin D status are needed to further explore optimal cut-offs or non-linear associations (including for maternal health) that might exist among populations with sub-optimal exposure.

Season and vitamin D status are independently associated with glucose homeostasis in pregnancy

BACKGROUND

Vitamin D status and season are intrinsically linked, and both have been proposed to be associated with glucose homeostasis in pregnancy, with conflicting results. We aimed to determine if exposure to winter and low maternal 25 hydroxyvitamin D (25OHD) in early pregnancy were associated with maternal glucose metabolism.

METHODS

This is a secondary data analysis of 334 pregnant women enrolled in the ROLO study, Dublin. Serum 25OHD, fasting glucose, insulin and insulin resistance (HOMA-IR) were measured in early (12 weeks' gestation) and late pregnancy (28 weeks' gestation). Season of first antenatal visit was categorised as extended winter (November-April) or extended summer (May-October). Multiple linear regression models, adjusted for confounders, were used for analysis.

RESULTS

Those who attended their first antenatal visit in extended winter had lower 25OHD compared to extended summer (32.9 nmol/L vs. 44.1 nmol/L, P < 0.001). Compared to those who attended their first antenatal visit during extended summer, extended winter was associated with increased HOMA-IR in early-pregnancy (46.7%) and late pregnancy (53.7%), independent of 25OHD <30 nmol/L and confounders. Early pregnancy 25OHD <30 nmol/L and extended winter were independently associated with significantly higher fasting glucose in late pregnancy (B = 0.15 and 0.13, respectively).

CONCLUSIONS

Women who attended their first antenatal visit during the months of extended winter were more likely to have raised insulin resistance in early pregnancy, which had a lasting association to 28 weeks, and was independent of 25OHD. Our novel findings imply that seasonal variation in insulin resistance may not be fully explained by differences in vitamin D status. This could reflect circannual rhythm or seasonal lifestyle behaviours, and requires further exploration.

TRIAL REGISTRATION

ISRCTN registry, ISRCTN54392969, date of registration: 22/04/2009, retrospectively registered.