William B. Grant

An Estimate of Premature Cancer Mortality in the U.S. Due to Inadequate Doses of Solar Ultraviolet-B Radiation

There are large geographic gradients in mortality rates for a number of cancers in the U.S. (e.g., rates are approximately twice as high in the northeast compared with the southwest). Risk factors such as diet fail to explain this variation. Previous studies have demonstrated that the geographic distributions for five types of cancer are related inversely to solar radiation. The purpose of the current study was to determine how many types of cancer are affected by solar radiation and how many premature deaths from cancer occur due to insufficient ultraviolet (UV)‐B radiation.

Vitamin D effects on musculoskeletal health, immunity, autoimmunity, cardiovascular disease, cancer, fertility, pregnancy, dementia and mortality—A review of recent evidence

BACKGROUND Optimal vitamin D intake and its status are important not only for bone and calcium-phosphate metabolism, but also for overall health and well-being. Vitamin D deficiency and insufficiency as a global health problem are likely to be a risk for wide spectrum of acute and chronic illnesses. METHODS A review of randomized controlled trials, meta-analyses, and other evidence of vitamin D action on various health outcomes. RESULTS Adequate vitamin D status seems to be protective against musculoskeletal disorders (muscle weakness, falls, fractures), infectious diseases, autoimmune diseases, cardiovascular disease, type 1 and type 2 diabetes mellitus, several types of cancer, neurocognitive dysfunction and mental illness, and other diseases, as well as infertility and adverse pregnancy and birth outcomes. Vitamin D deficiency/insufficiency is associated with all-cause mortality. CONCLUSIONS Adequate vitamin D supplementation and sensible sunlight exposure to reach optimal vitamin D status are among the front line factors of prophylaxis for the spectrum of disorders. Supplementation guidance and population strategies for the eradication of vitamin D deficiency must be included in the priorities of physicians, medical professionals and healthcare policy-makers.

Vitamin D and prevention of breast cancer: pooled analysis.

BACKGROUND Inadequate photosynthesis or oral intake of Vitamin D are associated with high incidence and mortality rates of breast cancer in ecological and observational studies, but the dose-response relationship in individuals has not been adequately studied. METHODS A literature search for all studies that reported risk by of breast cancer by quantiles of 25(OH)D identified two studies with 1760 individuals. Data were pooled to assess the dose-response association between serum 25(OH)D and risk of breast cancer. RESULTS The medians of the pooled quintiles of serum 25(OH)D were 6, 18, 29, 37 and 48 ng/ml. Pooled odds ratios for breast cancer from lowest to highest quintile, were 1.00, 0.90, 0.70, 0.70 and 0.50 (p trend<0.001). According to the pooled analysis, individuals with serum 25(OH)D of approximately 52 ng/ml had 50% lower risk of breast cancer than those with serum <13 ng/ml. This serum level corresponds to intake of 4000 IU/day. This exceeds the National Academy of Sciences upper limit of 2000 IU/day. A 25(OH)D level of 52 ng/ml could be maintained by intake of 2000 IU/day and, when appropriate, about 12 min/day in the sun, equivalent to oral intake of 3000 IU of Vitamin D(3). CONCLUSIONS Intake of 2000 IU/day of Vitamin D(3), and, when possible, very moderate exposure to sunlight, could raise serum 25(OH)D to 52 ng/ml, a level associated with reduction by 50% in incidence of breast cancer, according to observational studies.

Validation of the Saharan Dust Plume Conceptual Model Using Lidar, Meteosat, and ECMWF Data

Abstract Lidar observations collected during the Lidar In-space Technology Experiment experiment in conjunction with the Meteosat and European Centre for Medium-Range Weather Forecasts data have been used not only to validate the Saharan dust plume conceptual model constructed from the GARP (Global Atmospheric Research Programme) Atlantic Tropical Experiment data, but also to examine the vicissitudes of the Saharan aerosol including their optical depths across the west Africa and east Atlantic regions. Optical depths were evaluated from both the Meteosat and lidar data. Back trajectory calculations were also made along selected lidar orbits to verify the characteristic anticyclonic rotation of the dust plume over the eastern Atlantic as well as to trace the origin of a dust outbreak over West Africa. A detailed synoptic analysis including the satellite-derived optical depths, vertical lidar backscattering cross section profiles, and back trajectories of the 16–19 September 1994 Saharan dust outbreak over ...

Vitamin D and prevention of colorectal cancer.

BACKGROUND Inadequate photosynthesis or oral intake of Vitamin D are associated with high incidence rates of colorectal cancer, but the dose-response relationship has not been adequately studied. METHODS Dose-response gradients from observational studies of Vitamin D intake and serum 25-hydroxyvitamin D were plotted as trend lines. The point on each linear trend line corresponding to an odds ratio of 0.50 provided the prediagnostic Vitamin D intake or 25-hydroxyvitamin D concentration associated with 50% lower risk compared to <100IU/day Vitamin D or <13ng/ml serum 25-hydroxyvitamin D. Medians of these values were determined. RESULTS Overall, individuals with >or=1000IU/day oral Vitamin D (p<0.0001) or >or=33ng/ml (82nmol/l) serum 25-hydroxyvitamin D (p<0.01) had 50% lower incidence of colorectal cancer compared to reference values. CONCLUSIONS Intake of 1000IU/day of Vitamin D, half the safe upper intake established by the National Academy of Sciences, was associated with 50% lower risk. Serum 25-hydroxyvitamin D of 33ng/ml, which is known to be safe, also was associated with 50% lower risk. Prompt public health action is needed to increase intake of Vitamin D(3) to 1000IU/day, and to raise 25-hydroxyvitamin D by encouraging a modest duration of sunlight exposure.

A prospective study of psychological predictors of lumbar surgery outcome.

Study Design. Prospective design in which 102 patients were evaluated with a battery of psychological assessment tests 1–2 weeks before surgery, and outcome was assessed 6 months and 1 year after surgery. Objectives. The study examined whether three aspects of psychological distress (depression, anxiety, and hostility) predict several surgical outcomes (employment status, subjective pain change ratings, and changes in functional abilities). Summary of Background Data. Surgery for back pain has been shown to yield poor results in 15–45% of patients. Tools are needed to identify those “at risk” for poor outcome. Aspects of emotional distress, including anxiety, depression, and hostility, have been found to be relevant to various illness outcomes (e.g., cancer, heart disease), but their influence has not been prospectively evaluated for back pain surgical outcome. Methods. Study patients completed measures of distress before surgery, including the Spielberger Trait Anxiety Inventory, Zung Depression Scale, Modified Somatic Perception Questionnaire, and Cook–Medley Hostility Scale. At 1-year follow-up, patients completed pain change ratings, functional abilities measure (Dallas Pain Questionnaire), and questions about employment status. Results. Multivariate regression analyses, controlling for significant demographic variables, found that failure to return to work was predicted by presurgical anxiety (P < 0.001) and depression (P < 0.01); failure to report improvement in pain was predicted by presurgical somatic anxiety (P < 0.01) and depression (P < 0.058); and failure to report improved functional abilities was predicted by presurgical somatic anxiety (P < 0.01) and depression (P < 0.05). Hostility did not predict any outcome. Regression analyses found a strong predictor to be a combination of the Zung Depression Scale and Modified Somatic Perception Questionnaire, known as the Distress and Risk Assessment Method (DRAM). Conclusions. These results indicate that screening for presurgical distress is likely to identify those patients at risk for poor outcome. Studies to evaluate whether presurgical psychological treatment improves outcome are warranted.

An ecologic study of dietary and solar ultraviolet-B links to breast carcinoma mortality rates

The role of diet in the etiology of breast carcinoma has been debated for decades. The ecologic approach generally finds that dietary fat is highly associated with breast carcinoma mortality, with fish intake and solar ultraviolet‐B (UV‐B) radiation, a source of vitamin D, inversely associated. Case–control and cohort studies generally find a variety of chemical, nonfat dietary, environmental, genetic, lifestyle, and reproductive factors to be important.

Vitamin D Status and Mortality Risk in CKD: A Meta-analysis of Prospective Studies

BACKGROUND Vitamin D deficiency, assessed as low 25-hydroxyvitamin D (25[OH]D) level, is highly prevalent in patients with chronic kidney disease (CKD) and is associated with various adverse health outcomes. Whether low 25(OH)D levels in patients with CKD are an independent risk factor for mortality remains to be studied in detail, and this was the objective of our work. STUDY DESIGN A systematic review and meta-analysis of prospective observational studies. SETTING & POPULATION Patients with CKD. CKD was diagnosed mainly as decreased estimated glomerular filtration rate. SELECTION CRITERIA FOR STUDIES We performed a systematic literature search in MEDLINE, ISI, and EMBASE to identify prospective studies reporting on 25(OH)D levels and mortality. PREDICTOR 25(OH)D serum concentrations. OUTCOME All-cause mortality. RESULTS 10 studies with an overall sample of 6,853 patients with CKD were included. Relative risk of mortality per 10-ng/mL (25-nmol/L) increase in 25(OH)D level was 0.86 (95% CI, 0.82-0.91), with no indication of publication bias or significant heterogeneity (I(2) =15%; P = 0.3). Summary estimates for CKD cohorts with and without dialysis treatment showed homogeneous results (P = 0.9). LIMITATIONS Results may be limited by heterogeneity, unconsidered confounders, and the observational design of the studies. Furthermore, publication bias by unpublished null findings on the association of 25(OH)D level and mortality cannot be ruled out and ascertainment of CKD was based largely on estimated glomerular filtration rate. CONCLUSIONS Higher 25(OH)D levels are associated with significantly improved survival in patients with CKD. Whether treatment of low 25(OH)D level using natural vitamin D supplementation improves survival in patients with CKD remains to be elucidated in randomized controlled trials.

Vitamin D, cardiovascular disease and mortality

A poor vitamin D status, i.e. low serum levels of 25‐hydroxyvitamin D [25(OH)D], is common in the general population. This finding is of concern not only because of the classic vitamin D effects on musculoskeletal outcomes, but also because expression of the vitamin D receptor (VDR) and vitamin D metabolizing enzymes in the heart and blood vessels suggests a role of vitamin D in the cardiovascular system. VDR‐knockout mice suffer from cardiovascular disease (CVD), and various experimental studies suggest cardiovascular protection by vitamin D, including antiatherosclerotic, anti‐inflammatory and direct cardio‐protective actions, beneficial effects on classic cardiovascular risk factors as well as suppression of parathyroid hormone (PTH) levels. In epidemiological studies, low levels of 25(OH)D are associated with increased risk of CVD and mortality. Data from randomized controlled trials (RCTs) are sparse and have partially, but not consistently, shown some beneficial effects of vitamin D supplementation on cardiovascular risk factors (e.g. arterial hypertension). We have insufficient data on vitamin D effects on cardiovascular events, but meta‐analyses of RCTs indicate that vitamin D may modestly reduce all‐cause mortality. Despite accumulating data suggesting that a sufficient vitamin D status may protect against CVD, we still must wait for results of large‐scale RCTs before raising general recommendations for vitamin D in the prevention and treatment of CVD. In current clinical practice, the overall risks and costs of vitamin D supplementation should be weighed against the potential adverse consequences of untreated vitamin D deficiency.

Aerosols from biomass burning over the tropical South Atlantic region: Distributions and impacts

The NASA Global Tropospheric Experiment (GTE) Transport and Atmospheric Chemistry Near the Equator-Atlantic (TRACE A) expedition was conducted September 21 through October 26, 1992, to investigate factors responsible for creating the seasonal South Atlantic tropospheric ozone maximum. During these flights, fine aerosol (0.1–3.0 μm) number densities were observed to be enhanced roughly tenfold over remote regions of the tropical South Atlantic and greater over adjacent continental areas, relative to northern hemisphere observations and to measurements recorded in the same area during the wet season. Chemical and meteorological analyses as well as visual observations indicate that the primary source of these enhancements was biomass burning occurring within grassland regions of north central Brazil and southeastern Africa. These fires exhibited fine aerosol (N) emission ratios relative to CO (dN/dCO) of 22.5 ± 9.7 and 23.6 ± 15.1 cm−3 parts per billion by volume (ppbv)−1 over Brazil and Africa, respectively. Convection coupled with counterclockwise flow around the South Atlantic subtropical anticyclone subsequently distributed these aerosols throughout the remote South Atlantic troposphere. We calculate that dilute smoke from biomass burning produced an average tenfold enhancement in optical depth over the continental regions as well as a 50% increase in this parameter over the middle South Atlantic Ocean; these changes correspond to an estimated net cooling of up to 25 W m−2 and 2.4 W m−2 during clear-sky conditions over savannas and ocean respectively. Over the ocean our analyses suggest that modification of CCN concentrations within the persistent eastern Atlantic marine stratocumulus clouds by entrainment of subsiding haze layers could significantly increase cloud albedo resulting in an additional surface radiative cooling potentially greater in magnitude than that caused by direct extinction of solar radiation by the aerosol particles themselves.