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Background: Vitamin D has been identified as a potential protective factor in the development of colorectal cancer (CRC). We expect to see a stronger association of ultraviolet B (UVB) exposure and CRC crude rates with increasing age since chronic vitamin D deficiency leads to sustained molecular changes that increase cancer risk. The DINOMIT (disjunction, initiation, natural selection, overgrowth, metastasis, involution, and transition) model postulates various stages of cancer development due to vitamin D deficiency and the associated latency period. The purpose of this study is to examine this age-dependent inverse relationship globally.Methods: In this ecological study, a series of linear and polynomial regression tests were performed between country-specific UVB estimates adjusted for cloud cover and crude incidence rates of CRC for different age groups. Multiple linear regression was used to investigate the association between crude incidence rates of colorectal cancer and UVB estimate adjusting for urbanization, skin pigmentation, smoking, animal consumption, per capita GDP, and life expectancy. Statistical analysis was followed by geospatial visualization by producing choropleth maps.Results: The inverse relationship between UVB exposure and CRC crude rates was stronger in older age groups at the country level. Quadratic curve fitting was preferred, and these models were statistically significant for all age groups. The inverse association between crude incidence rates of CRC and UVB exposure was statistically significant for age groups above 45 years, after controlling for covariates.Conclusion: The age-dependent inverse association between UVB exposure and incidence of colorectal cancer exhibits a greater effect size among older age groups in global analyses. Studying the effect of chronic vitamin D deficiency on colorectal cancer etiology will help in understanding the necessity for population-wide screening programs for vitamin D deficiency, especially in regions with inadequate UVB exposure. Further studies are required to assess the need for adequate public health programs such as selective supplementation and food fortification. [ABSTRACT FROM AUTHOR]

Background: While numerous epidemiologic studies have found an association between higher serum 25-hydroxyvitamin D [25(OH)D] concentrations and lower breast cancer risk, few have assessed this association for concentrations >40 ng/ml. Objective: To investigate the relationship between 25(OH)D concentration and breast cancer risk across a broad range of 25(OH)D concentrations among women aged 55 years and older. Methods: Analyses used pooled data from two randomized clinical trials (N = 1129, N = 2196) and a prospective cohort (N = 1713) to examine a broad range of 25(OH)D concentrations. The outcome was diagnosis of breast cancer during the observation periods (median: 4.0 years). Three analyses were conducted: 1) Incidence rates were compared according to 25(OH)D concentration from <20 to ≥60 ng/ml (<50 to ≥150 nmol/L), 2) Kaplan-Meier plots were developed and 3) multivariate Cox regression was used to examine the association between 25(OH)D and breast cancer risk using multiple 25(OH)D measurements. Results: Within the pooled cohort (N = 5038), 77 women were diagnosed with breast cancer (age-adjusted incidence: 512 cases per 100,000 person-years). Results were similar for the three analyses. First, comparing incidence rates, there was an 82% lower incidence rate of breast cancer for women with 25(OH)D concentrations ≥60 vs <20 ng/ml (Rate Ratio = 0.18, P = 0.006). Second, Kaplan-Meier curves for concentrations of <20, 20–39, 40–59 and ≥60 ng/ml were significantly different (P = 0.02), with the highest proportion breast cancer-free in the ≥60 ng/ml group (99.3%) and the lowest proportion breast cancer-free in the <20 ng/ml group (96.8%). The proportion with breast cancer was 78% lower for ≥60 vs <20 ng/ml (P = 0.02). Third, multivariate Cox regression revealed that women with 25(OH)D concentrations ≥60 ng/ml had an 80% lower risk of breast cancer than women with concentrations <20 ng/ml (HR = 0.20, P = 0.03), adjusting for age, BMI, smoking status, calcium supplement intake, and study of origin. Conclusions: Higher 25(OH)D concentrations were associated with a dose-response decrease in breast cancer risk with concentrations ≥60 ng/ml being most protective. [ABSTRACT FROM AUTHOR]

Background: It has been reported that higher plasma 25-hydroxyvitamin D is associated with lower risk of type 2 diabetes. However the results to date have been mixed and no adequate data based on a cohort are available for the high end of the normal range, above approximately 32 ng/ml or 80 nmol/L. Methods: We performed a cohort study of 903 adults who were known to be free of diabetes or pre-diabetes during a 1997–1999 visit to a NIH Lipid Research Centers clinic. Plasma 25(OH)D was measured at Visit 8 in 1977–1979. The mean age was 74 years. The visit also included fasting plasma glucose and oral glucose tolerance testing. Follow-up continued through 2009. Results: There were 47 cases of diabetes and 337 cases of pre-diabetes. Higher 25(OH)D concentrations (> 30 ng/ml) were associated with lower hazard ratios (HR) for diabetes: 30–39 ng/ml or 75–98 nmol/L: HR = 0.31, 95% CI = 0.14–0.70; for 40–49 ng/ml or 100–122 nmol/L: HR = 0.29, CI = 0.12–0.68; for > 50 ng/ml or 125 nmol/L: HR = 0.19, CI = 0.06–0.56. All HRs are compared to < 30 ng/ml or 75 nmol/L. There was an inverse dose-response gradient between 25(OH)D concentration and risk of diabetes with a p for trend of 0.005. Each 10 ng/mL or 25 nmol/L higher 25(OH)D concentration was associated with a HR of 0.64, CI = 0.48–0.86. 25(OH)D concentrations were more weakly inversely associated with pre-diabetes risk, and the trend was not significant. Conclusion: Further research is needed on whether high 25(OH)D might prevent type 2 diabetes or transition of prediabetes to diabetes. [ABSTRACT FROM AUTHOR]

Introduction: Sex hormones have been implicated in the etiology of a number of diseases. To better understand disease etiology and the mechanisms of disease-risk factor associations, this analysis aimed to investigate the associations of anthropometric, sociodemographic and behavioural factors with a range of circulating sex hormones and sex hormone-binding globulin. Methods: Statistical analyses of individual participant data from 12,330 male controls aged 25–85 years from 25 studies involved in the Endogenous Hormones Nutritional Biomarkers and Prostate Cancer Collaborative Group. Analysis of variance was used to estimate geometric means adjusted for study and relevant covariates. Results: Older age was associated with higher concentrations of sex hormone-binding globulin and dihydrotestosterone and lower concentrations of dehydroepiandrosterone sulfate, free testosterone, androstenedione, androstanediol glucuronide and free estradiol. Higher body mass index was associated with higher concentrations of free estradiol, androstanediol glucuronide, estradiol and estrone and lower concentrations of dihydrotestosterone, testosterone, sex hormone-binding globulin, free testosterone, androstenedione and dehydroepiandrosterone sulfate. Taller height was associated with lower concentrations of androstenedione, testosterone, free testosterone and sex hormone-binding globulin and higher concentrations of androstanediol glucuronide. Current smoking was associated with higher concentrations of androstenedione, sex hormone-binding globulin and testosterone. Alcohol consumption was associated with higher concentrations of dehydroepiandrosterone sulfate, androstenedione and androstanediol glucuronide. East Asians had lower concentrations of androstanediol glucuronide and African Americans had higher concentrations of estrogens. Education and marital status were modestly associated with a small number of hormones. Conclusion: Circulating sex hormones in men are strongly associated with age and body mass index, and to a lesser extent with smoking status and alcohol consumption. [ABSTRACT FROM AUTHOR]

Background: Higher serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with a lower risk of multiple cancer types across a range of 25(OH)D concentrations. Objectives: To investigate whether the previously reported inverse association between 25(OH)D and cancer risk could be replicated, and if a 25(OH)D response region could be identified among women aged 55 years and older across a broad range of 25(OH)D concentrations. Methods: Data from two cohorts representing different median 25(OH)D concentrations were pooled to afford a broader range of 25(OH)D concentrations than either cohort alone: the Lappe cohort (N = 1,169), a randomized clinical trial cohort (median 25(OH)D = 30 ng/ml) and the GrassrootsHealth cohort (N = 1,135), a prospective cohort (median 25(OH)D = 48 ng/ml). Cancer incidence over a multi-year period (median: 3.9 years) was compared according to 25(OH)D concentration. Kaplan-Meier plots were developed and the association between 25(OH)D and cancer risk was examined with multivariate Cox regression using multiple 25(OH)D measurements and spline functions. The study included all invasive cancers excluding skin cancer. Results: Age-adjusted cancer incidence across the combined cohort (N = 2,304) was 840 cases per 100,000 person-years (1,020 per 100,000 person-years in the Lappe cohort and 722 per 100,000 person-years in the GrassrootsHealth cohort). Incidence was lower at higher concentrations of 25(OH)D. Women with 25(OH)D concentrations ≥40 ng/ml had a 67% lower risk of cancer than women with concentrations <20 ng/ml (HR = 0.33, 95% CI = 0.12–0.90). Conclusions: 25(OH)D concentrations ≥40 ng/ml were associated with substantial reduction in risk of all invasive cancers combined. [ABSTRACT FROM AUTHOR]

There are 52,380 cases of leukemia and 24,090 deaths from it in the US annually. Its causes are unknown and no preventive strategies have been implemented. We hypothesized that leukemia is due mainly to vitamin D deficiency, which is due mainly to low solar ultraviolet B (UVB) irradiance. To test this hypothesis, we estimated age-standardized cloud-cover-adjusted winter UVB irradiance using cloud cover data from the International Satellite Cloud Climatology Project, latitudes of population centroids, and standard astronomical calculations. Incidence rates for 172 countries, available from the International Agency for Cancer Research, were plotted according to cloud-adjusted UVB irradiance. We used multiple regression to account for national differences in elevation and average life expectancy. Leukemia incidence rates were inversely associated with cloud-adjusted UVB irradiance in males (p ≤ 0.01) and females (p ≤ 0.01) in both hemispheres. There were few departures from the trend line, which was parabolic when plotted with the equator at the center of the display, northern hemisphere countries on the right side and southern hemisphere countries on the left. The bivariate association displayed by the polynomial trend line indicated that populations at higher latitudes had at least two times the risk of leukemia compared to equatorial populations. The association persisted in males (p ≤ 0.05) and females (p ≤ 0.01) after controlling for elevation and life expectancy. Incidence rates of leukemia were inversely associated with solar UVB irradiance. It is plausible that the association is due to vitamin D deficiency. This would be consistent with laboratory studies and a previous epidemiological study. Consideration should be given to prudent use of vitamin D for prevention of leukemia. [ABSTRACT FROM AUTHOR]

The authors remind that the full solar spectrum is essential to optimal public health and well-being as they caution that the current policy of sun avoidance is creating probable harm for the general population. They discuss heliotheraphy, the use of the healing power of the sun in medical treatment, as well as the elevation of vitamin status as the best recognized response to sun exposure. They also examine the impact of sunlight and vitamin D on cancer, pregnancy and Type I diabetes.

Objectives. Increasing 25-hydroxyvitamin D serum levels can prevent a wide range of diseases. There is a concern about increasing kidney stone risk with vitamin D supplementation. We used GrassrootsHealth data to examine the relationship between vitamin D status and kidney stone incidence. Methods. The study included 2012 participants followed prospectively for a median of 19 months. Thirteen individuals self-reported kidney stones during the study period. Multivariate logistic regression was applied to assess the association between vitamin D status and kidney stones. Results. We found no statistically significant association between serum 25-hydroxyvitamin D and kidney stones (P=.42). Body mass index was significantly associated with kidney stone risk (odds ratio = 3.5; 95% confidence interval = 1.1, 11.3). Conclusions. We concluded that a serum 25-hydroxyvitamin D level of 20 to 100 nanograms per milliliter has no significant association with kidney stone incidence. [ABSTRACT FROM AUTHOR]

We examined the relationship between serum 25- hydroxyvitaminD(25[OH]D) and all-cause mortality. We searched biomedical databases for articles that assessed 2 ormore categories of 25(OH)D from January 1, 1966, to January 15, 2013. We identified 32 studies and pooled the data. The hazard ratio for allcause mortality comparing the lowest (0–9 nanograms per milliliter [ng/mL]) to the highest (> 30 ng/mL) category of 25(OH)D was 1.9 (95% confidence interval = 1.6, 2.2; P < .001). Serum 25 (OH)D concentrations less than or equal to 30 ng/mL were associated with higher all-causemortality than concentrations greater than 30 ng/mL (P < .01). Our findings agree with a National Academy of Sciences report, except the cutoff point for all-cause mortality reduction in this analysis was greater than 30 ng/mL rather than greater than 20 ng/mL. [ABSTRACT FROM AUTHOR]

Background: Most previous research that has examined mental health among Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF) combatants has relied on self-report measures to assess mental health outcomes; few studies have examined predictors of actual mental health diagnoses. The objective of this longitudinal investigation was to identify predictors of psychiatric disorders among Marines who deployed to combat in Iraq and Afghanistan. Methods: The study sample consisted of 1113 Marines who had deployed to Iraq or Afghanistan. Demographic and psychosocial predictor variables from a survey that all Marines in the sample had completed were studied in relation to subsequent psychiatric diagnoses. Univariate and multivariate logistic regression were used to determine the influence of the predictors on the occurrence of psychiatric disorders. Results: In a sample of Marines with no previous psychiatric disorder diagnoses, 18% were diagnosed with a new-onset psychiatric disorder. Adjusting for other variables, the strongest predictors of overall psychiatric disorders were female gender, mild traumatic brain injury symptoms, and satisfaction with leadership. Service members who expressed greater satisfaction with leadership were about half as likely to develop a mental disorder as those who were not satisfied. Unique predictors of specific types of mental disorders were also identified. Conclusions: Overall, the study's most relevant result was that two potentially modifiable factors, low satisfaction with leadership and low organizational commitment, predicted mental disorder diagnoses in a military sample. Additional research should aim to clarify the nature and impact of these factors on combatant mental health. [ABSTRACT FROM AUTHOR]

A wide range of epidemiologic and laboratory studies combined provide compelling evidence of a protective role of vitamin D on risk of breast cancer. This review evaluates the scientific evidence for such a role in the context of the A.B. Hill criteria for causality, in order to assess the presence of a causal, inverse relationship, between vitamin D status and breast cancer risk. After evaluation of this evidence in the context of Hill's criteria, it was found that the criteria for a causal relationship were largely satisfied. Studies in human populations and the laboratory have consistently demonstrated that vitamin D plays an important role in the prevention of breast cancer. Vitamin D supplementation is an urgently needed, low cost, effective, and safe intervention strategy for breast cancer prevention that should be implemented without delay. In the meantime, randomized controlled trials of high doses of vitamin D3 for prevention of breast cancer should be undertaken to provide the necessary evidence to guide national health policy. [ABSTRACT FROM AUTHOR]

Low serum 25-hydroxyvitamin D [25(OH)D] concentrations are associated with hip fractures, but the dose-response relationship of serum 25(OH)D with risk of stress fractures in young women is unknown. This nested case-control study in a cohort of female Navy recruits was designed to determine whether those with low prediagnostic serum 25(OH)D concentrations had greater risk of stress fracture. Sera were drawn in 2002-2009 from 600 women who were diagnosed subsequently with stress fracture of the tibia or fibula and 600 matched controls who did not experience a stress fracture. The 25(OH)D concentration was measured using the DiaSorin radioimmunoassay method. Controls were individually matched to cases on race (white, black, or other), length of service (±30 days), and day blood was drawn (±2 days). There was approximately half the risk of stress fracture in the top compared with the bottom quintile of serum 25(OH)D concentration (odds ratio [OR] = 0.51, 95% CI 0.34-0.76, p ≤ 0.01). The range of serum 25(OH)D in the lowest quintile was 1.5 to 19.7 (mean 13.9) ng/mL, whereas in the highest it was 39.9 to 112 (mean 49.7) ng/mL. It is concluded that there was a monotonic inverse dose-response gradient between serum 25(OH)D and risk of stress fracture. There was double the risk of stress fractures of the tibia and fibula in women with serum 25(OH)D concentrations of less than 20 ng/mL compared to those with concentrations of 40 ng/mL or greater. A target for prevention of stress fractures would be a serum 25(OH)D concentration of 40 ng/mL or greater, achievable with 4000 IU/d of vitamin D3 supplementation. © 2011 American Society for Bone and Mineral Research [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to determine whether an inverse association exists between latitude, solar ultraviolet B (UVB) irradiance, modeled 25-hydroxyvitamin D [25(OH)D] levels and incidence rates of cancer of the brain. Methods: Associations of latitude and UVB irradiance with age-standardized incidence rates of cancer of the brain were analyzed for 175 countries while controlling for proportion of population overweight, energy from animal sources, fish consumption, cigarette and alcohol consumption and per capita health expenditures, using multiple regression. Serum 25(OH)D levels were modeled for each country, and their association with brain cancer also was determined. Results: The incidence rates of brain cancer were higher at higher latitudes (R2 for males = 0.45, p ≤ 0.0001; R2 for females = 0.35, p < 0.0001). After adjustment for potential confounders, UVB irradiance (p ≤ 0.0001) and modeled serum 25(OH)D were inversely associated with incidence rates. Conclusions: Countries with low solar UVB irradiance and estimated mean serum 25(OH)D levels generally had higher age-standardized incidence rates of brain cancer. Since this was an ecological study, further research would be worthwhile on the association of prediagnostic serum 25(OH)D with incidence rate in studies of cohorts of individuals. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The objective of this study was to identify factors associated with antisocial behavior in 1,543 Marines who deployed to combat zones in support of conflicts in Iraq and Afghanistan during 2002–2007. Five factors were associated with antisocial behavior in multivariate analyses: post-traumatic stress disorder (PTSD) symptoms, deployment-related stressors, combat exposure, younger age, and being divorced. PTSD symptoms had a stronger association with antisocial behavior than any other variable. A unique and important finding of this study was the association between deployment-related stressors and a higher incidence of antisocial behavior. Because deployment-related stressors are potentially modifiable, the military may be able to address them in concrete ways such as by shortening deployments and improving communication with home. Aggr. Behav. 36:330–337, 2010. Published 2010 by Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The effect of combat and operational stress on the mental health of military personnel is a major concern. The objective of this study was to identify factors associated with possible posttraumatic stress disorder (PTSD). A questionnaire was completed by 1,569 Marines who deployed in support of conflicts in Iraq and Afghanistan (2002–2007). Using the PTSD Checklist with a cutoff score of 44, 17.1% of the sample screened positive for possible PTSD. Of 9 demographic and psychosocial factors examined in relation to PTSD, 4 were significant in a multivariate analysis: deployment-related stressors, combat exposure, marital status, and education. Deployment-related stressors had a stronger association with PTSD than any other variable. This is an important finding because deployment-related stressors are potentially modifiable. [ABSTRACT FROM AUTHOR]

Background: Research on Vietnam veterans suggests an association between psychological problems, including posttraumatic stress disorder (PTSD), and misconduct; however, this has rarely been studied in veterans of Operation Iraqi Freedom or Operation Enduring Freedom. The objective of this study was to investigate whether psychological problems were associated with three types of misconduct outcomes (demotions, drug-related discharges, and punitive discharges.) Methods: A population-based study was conducted on all U.S. Marines who entered the military between October 1, 2001, and September 30, 2006, and deployed outside of the United States before the end of the study period, September 30, 2007. Demographic, psychiatric, deployment, and personnel information was collected from military records. Cox proportional hazards regression analysis was conducted to investigate associations between the independent variables and the three types of misconduct in war-deployed (n = 77 998) and non-war-deployed (n = 13 944) Marines. Results: Marines in both the war-deployed and non-war-deployed cohorts with a non-PTSD psychiatric diagnosis had an elevated risk for all three misconduct outcomes (hazard ratios ranged from 3.93 to 5.65). PTSD was a significant predictor of drug-related discharges in both the war-deployed and non-war-deployed cohorts. In the war-deployed cohort only, a specific diagnosis of PTSD was associated with an increased risk for both demotions (hazard ratio, 8.60; 95% confidence interval, 6.95 to 10.64) and punitive discharges (HR, 11.06; 95% CI, 8.06 to 15.16). Conclusions: These results provide evidence of an association between PTSD and behavior problems in Marines deployed to war. Moreover, because misconduct can lead to disqualification for some Veterans Administration benefits, personnel with the most serious manifestations of PTSD may face additional barriers to care. [ABSTRACT FROM AUTHOR]

Epidemiological data show an inverse relationship between vitamin D levels and breast cancer incidence. This study investigates the relationship of modeled and measured serum 25-hydroxyvitamin D [25(OH)D] levels with age-standardized incidence rates of breast cancer in 107 countries. The hypothesis being tested is that breast cancer incidence is inversely related to geographically-dependent cutaneous sunlight exposure. A multiple regression approach was used to examine the contributions of ultraviolet B (UVB) irradiance to age-standardized incidence rates of breast cancer in the 107 countries with data on these covariates—total column ozone thickness, per capita intake of alcohol and energy from animal and vegetable sources, cigarettes, proportion of female population overweight, and total fertility. Age-standardized incidence rates were substantially higher at latitudes distant from the equator ( R 2 = 0.43, p < 0.0001). The dose–response gradient between modeled serum 25(OH)D levels and incidence rates of breast cancer followed a standard inverse dose–response curve. Increasing increments in serum 25(OH)D in the range above 22 ng/mL were associated with incrementally lower incidence rates of breast cancer. According to multiple regression, UVB irradiance adjusted for cloud cover was inversely associated with incidence rates (p = 0.04) after controlling for covariates. Intake of energy from animal sources was also positively associated with incidence rates (p < 0.01). The overall coefficient of determination, R2, was 0.81 (p < 0.0001). There was a protective effect of UVB irradiance on risk of breast cancer that was independent of fertility rate, proportion of the population overweight, alcohol intake, animal energy intake, and other covariates. [ABSTRACT FROM AUTHOR]

The epidemiology of influenza swarms with incongruities, incongruities exhaustively detailed by the late British epidemiologist, Edgar Hope-Simpson. He was the first to propose a parsimonious theory explaining why influenza is, as Gregg said, "seemingly unmindful of traditional infectious disease behavioral patterns." Recent discoveries indicate vitamin D upregulates the endogenous antibiotics of innate immunity and suggest that the incongruities explored by Hope-Simpson may be secondary to the epidemiology of vitamin D deficiency. We identify -- and attempt to explain -- nine influenza conundrums: (1) Why is influenza both seasonal and ubiquitous and where is the virus between epidemics? (2) Why are the epidemics so explosive? (3) Why do they end so abruptly? (4) What explains the frequent coincidental timing of epidemics in countries of similar latitude? (5) Why is the serial interval obscure? (6) Why is the secondary attack rate so low? (7) Why did epidemics in previous ages spread so rapidly, despite the lack of modern transport? (8) Why does experimental inoculation of seronegative humans fail to cause illness in all the volunteers? (9) Why has influenza mortality of the aged not declined as their vaccination rates increased? We review recent discoveries about vitamin D's effects on innate immunity, human studies attempting sick-to-well transmission, naturalistic reports of human transmission, studies of serial interval, secondary attack rates, and relevant animal studies. We hypothesize that two factors explain the nine conundrums: vitamin D's seasonal and population effects on innate immunity, and the presence of a subpopulation of "good infectors." If true, our revision of Edgar Hope-Simpson's theory has profound implications for the prevention of influenza. [ABSTRACT FROM AUTHOR]

The article looks at nutrition research which examined the relationship between vitamin D and the risk of various cancers, such as ovary, colon, and breast cancer. According to the article, a dose-response gradient is a crucial component for determining whether or not the association between cancer risk and vitamin D is causal. The article discusses sunlight exposure, intercelluar junctions, E-cadherin, decoupling, vascular endothelial growth factors, and the ways in which vitamin D prevents cancer, which include tumor angiogenesis prevention.

Incidence rates of kidney cancer are thought to be highest in places situated at high latitudes and in populations with high intake of energy from animal sources. This suggests that low 25-hydroxyvitamin D status, due to lower levels of UVB irradiance, and energy from animal sources might be involved in etiology. The association of latitude with age-adjusted incidence rates was determined for all 175 countries in a UN cancer database, GLOBOCAN. The independent association of UVB irradiance, cloud cover and intake of calories from animal sources with age-adjusted incidence rates was assessed using multiple regression in 139 countries that provided dietary data. Renal cancer incidence rates were highest in countries situated at the highest latitudes, in men ( R [ABSTRACT FROM AUTHOR]

Vitamin D status differs by latitude and race, with residents of the northeastern United States and individuals with more skin pigmentation being at increased risk of deficiency. A PubMed database search yielded 63 observational studies of vitamin D status in relation to cancer risk, including 30 of colon, 13 of breast, 26 of prostate, and 7 of ovarian cancer, and several that assessed the association of vitamin D receptor genotype with cancer risk. The majority of studies found a protective relationship between sufficient vitamin D status and lower risk of cancer. The evidence suggests that efforts to improve vitamin D status, for example by vitamin D supplementation, could reduce cancer Incidence and mortality at low cost, with few or no adverse effects. [ABSTRACT FROM AUTHOR]

Study objectives: This study examines long-term trends in incidence rates of hospitalized pulmonary sarcoidosis in a large cohort of Navy personnel, and evaluates the possible relationship of sarcoidosis with occupation. Design: Incidence rates of first hospitalizations were determined for black and white male Navy enlisted personnel on active duty from 1975 to 2001. Setting: Navy service includes a potential for exposure to a variety of substances, including nonskid coatings used on ship decks that may be aerosolized during removal. Particulate matter containing aluminum, titanium, and silicates has been identified in nonskid samples. Specific occupational groups may have had greater exposure potential than others. Patients or participants: Hospitalized cases included sarcoidosis (n = 674), asthma (n = 3,536), emphysema and chronic bronchitis (n = 1,103), respiratory conditions due to fumes and vapors (n = 61), and pneumoconiosis (n = 51) observed in 9,953,607 person-years of active-duty service. Interventions: None. However, improvements were made in personal protective gear and other countermeasures to prevent or limit respiratory exposures during service. Measurements and results: Annual overall hospitalized sarcoidosis incidence rates per 100,000 were 24.9 for black men and 3.5 for white men (black/white ratio of 7.1, p < 0.0001). Annual incidence rates in blacks declined markedly, particularly since 1989, but the black/white ratio remained high through 1999. Occupational associations were present in blacks and whites. Black ship's servicemen (23 cases) and aviation structural mechanics specializing in structures (12 cases) had more than twice the expected incidence rate compared to all blacks, and white mess management specialists (15 cases) had twice the overall white incidence rate. Conclusions: There was a steep decline in incidence of hospitalized sarcoidosis in blacks in the Navy. Occupational associations suggest the possibility that a dust or moisture-related lung disease may have been erroneously classified as sarcoidosis, or, alternatively, that sarcoidosis had a previously unrecognized occupational component. [ABSTRACT FROM AUTHOR]

Vitamin D intake has been hypothesized to reduce the risk of several types of cancer. Vitamin D and its analogues have demonstrated anticancer activity in vitro and in animal models. However, the risk of colorectal cancer in relation to dietary vitamin D remains controversial. A literature search was performed for articles on epidemiologic studies of vitamin D and colorectal cancer and the mechanisms involved. Studies that combine multiple sources of vitamin D or examine serum 25(OH)D3 usually find that above-average vitamin D intake and serum metabolite concentrations are associated with significantly reduced incidence of colorectal cancer. A number of mechanisms have been identified through which vitamin D may reduce the risk of colorectal and several other types of cancer. Although studies that include vitamin D from all sources or serum 25(OH)D3 usually show significantly reduced incidence of colorectal cancer in association with vitamin D, analyses limited to dietary vitamin D tend to have mixed results. The likely reason that dietary vitamin D is not a significant risk reduction factor for colorectal cancer in many studies is that dietary sources provide only a portion of total vitamin D, with supplements and synthesis of vitamin D in the skin in association with solar UV-B radiation providing the balance. There is strong evidence from several different lines of investigation supporting the hypothesis that vitamin D may reduce the risk of colorectal cancer. Further study is required to elucidate the mechanisms and develop guidelines for optimal vitamin D sources and serum levels of vitamin D metabolites. [ABSTRACT FROM AUTHOR]

Comments on several articles published in the 'American Family Physician.' Algorithm for assessing bone mineral density in women; Role of vitamin D as a risk reduction factor for colorectal cancer; Guidelines for proper use of child safety seats.

Characterizes the incidence of illnesses and injuries from 1979 to 1993 in former naval aviator prisoners of war (POW) from the Vietnam War and a comparison group of naval aviators from the same war. POWs' higher rates of disorders of the peripheral nervous system, joints and back and peptic ulcer; Torture resulting in ischemia and subsequent neuropathies.

Background: In general, ovarian cancer incidence and mortality is higher in northern than southern latitudes. This ecologic study tests the hypothesis that vitamin D produced in the skin from sunlight exposure may be associated with a protective action in ovarian cancer mortality.Methods: The association between average annual sunlight energy and age-specific ovarian cancer mortality rates in counties containing the 100 largest US cities was evaluated for 1979-1988. Simple linear regression was performed by decade using sunlight and ozone as independent variables and ovarian cancer rates as the dependent variable. Multiple regression was used to adjust for ozone and sulphur dioxide, since these atmospheric components may absorb ultraviolet light.Results: Fatal ovarian cancer in these areas was inversely proportional to mean annual intensity of local sunlight in a univariate analysis (P = 0.0001), and in a regression adjusted for air pollution (P = 0.04). The association was also seen when restricted to 27 major urban areas of the US; however, probably due to a small sample size, this statistic did not reach significance.Conclusions: This ecologic study supports the hypothesis that sunlight may be a protective factor for ovarian cancer mortality. [ABSTRACT FROM AUTHOR]

Epidemiological and laboratory evidence suggest that vitamin D may play a role in reducing risk of breast cancer. Lack of exposure to ultraviolet sunlight can increase the prevalence of vitamin D deficiency, and may place some populations at higher risk of breast cancer. The association between total average annual sunlight energy striking the ground and age-adjusted breast cancer incidence rates in the USSR was evaluated. Breast cancer had a threefold range of incidence. Sunlight levels varied from 210 to 400 calories per cm per day. A statistically significant negative association was found between breast cancer incidence rates and total sunlight levels (R = −0.75, p = 0.001). The slope of the regression line corresponded to two additional cases per 100 000 per year for each reduction of 35 calories per cm of sunlight. The pattern of increased breast cancer incidence in regions of low solar radiation in the USSR is consistent with the geographical pattern seen for breast cancer mortality in the US and worldwide. A positive relationship between socioeconomic status and breast cancer incidence was also present in the Soviet Union, based on an approximate socioeconomic measure, the number of doctors per 1000 population (R = +0.89, p = 0.0001). The possibility that correlates of socioeconomic status, such as dietary, ethnic, or behavioural factors, could account for the association is discussed. [ABSTRACT FROM PUBLISHER]

Hodgkin's disease incidence has an early peak in young adulthood. The US Navy maintains computerized career history and hospitalization information for one of the largest defined populations of young adults available for prospective studies. There were approximately 2.3 million person-years at risk in white male enlisted personnel involved in more than 80 occupations in the Navy from 1974–79. During this period 88 incident cases were identified. Navy age-adjusted incidence rates of Hodgkin's disease did not differ significantly from US population rates. There was a slight, but not significant, increased incidence with increasing length of Navy service. One occupation, machinists' mate, had about double the risk of Hodgkin's disease as the entire Navy (SIR=2.3, p=0.004) and the US population (SIR = 1.8, ns). Probable exposures of machinists' mates include: volatile solvents, metal dusts and, possibly, ionizing radiation. Further studies are needed, however, to clarify this association. [ABSTRACT FROM PUBLISHER]

Garland CF (Department of Epidemiology, The Johns Hopkins University, School of Hygiene and Public Health, 615N Wolfe Street, Baltimore, Maryland 21205, USA) and Garland FC. Do sunlight and vitamin D reduce the likelihood of colon cancer. 1980, 9: 227–231. It is proposed that vitamin D is a protective factor against colon cancer. This hypothesis arose from inspection of the geographic distribution of colon cancer deaths in the U.S., which revealed that colon cancer mortality rates were highest in places where populations were exposed to the least amounts of natural light - major cities, and rural areas in high latitudes. The hypothesis is supported by a comparison of colon cancer mortality rates in areas that vary in mean daily solar radiation penetrating the atmosphere. A mechanism involving cholecalciferol (vitamin D) is suggested. The possibility that an ecological fallacy or other indirect association explains the findings is explored. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented in response to the article "Vitamin D and Risk of Cause Specific Death: Systematic Review and Meta-analysis of Observational Cohort and Randomised Intervention Studies," by R. Chowdhury and colleagues in the April 1, 2014 issue.

Several reports describe U-shaped 25-hydroxyvitamin D [25(OH)D] concentration–health outcomes, including musculo-skeletal disorders such as falls and fractures, several cancers, cardiovascular disease (CVD), cognitive function, all-cause mortality rates, birth outcomes, allergic reactions, frailty, and some other disorders. This paper reviews reports of U-shaped outcome associations with vitamin D status for evidence of underlying pathophysiological processes, or of confounding, finding that some U-shaped associations appear to be biologically meaningful, but that many could well reflect confounding by factors such as lifestyle, or hypovitaminosis D-related disease onset being masked by self-supplementation that was begun too late to correct developing health problems but before baseline vitamin D status assessment. However, the various U-shaped associations for allergic reactions may be due to vitamin D modulation of the phenotype of the immune response, shifting the Th1-Th2 balance toward Th2 formation. For prostate cancer, there seems to be little effect of 25(OH)D concentration on incidence; however, there is an inverse correlation between 25(OH)D concentration and mortality rates. Future observational studies, and randomized controlled trial data analyses, should include adjustment for data collected on prior long-term vitamin D supplementation and solar UVB exposure, as well as other potential confounders. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented in response to a study by D.M. Freedman and colleagues on the link between vitamin D and breast cancer mortality in the U.S.