Cost effectiveness of sodium zirconium cyclosilicate for the treatment of hyperkalaemia in patients with CKD in Norway and Sweden.

Background: Hyperkalaemia is common in patients with chronic kidney disease (CKD) and is associated with a range of adverse outcomes. Historically, options for management of chronic hyperkalaemia in the outpatient setting have been limited. Novel oral potassium binders provide a safe, effective therapy for maintenance of normokalaemia in patients with CKD, but despite being approved for reimbursement in many countries, prescription data indicate uptake has been slower than anticipated.

Influence of multiple UV exposures on serum cobalamin and vitamin D levels in healthy females.

Aims: Ultraviolet (UV) radiation is a major source for vitamin D production. Furthermore, UV destroys cobalamins (also called vitamin B12) in solution. However, data from humans are scarce.

Vitamin D levels and dietary intake among patients with benign soft tissue tumors and sarcomas.

Background: Calcitriol [1,25(OH)2D] is hypothesized to lower the risk of cancer via binding to the vitamin D receptor (VDR). VDRs are also found in benign and malignant cells of mesenchymal origin. To our knowledge, vitamin D levels and dietary intake have not been previously evaluated in patients newly diagnosed with benign and malignant mesenchymal tumors.

Increase in serum 25-hydroxyvitamin-D3 in humans after sunbed exposures compared to previtamin D3 synthesis in vitro.

Ultraviolet (UV) radiation is liable to cause skin cancer but it is the main source of vitamin D. Vitamin D photosynthesis takes place in skin at sub-erythemogenic UV doses, while larger exposures destroy vitamin D and increase DNA damage. Proper UV dosimetry is needed to obtain an optimal vitamin D status when skin cancer risk is minimal.

Vitamin D status in healthy Romanian caregivers and risk of respiratory infections.

Objectives: To investigate the vitamin D status during winter of a healthy population of hospital employees and to assess the correlation between vitamin D status and risk of infections in the upper respiratory tract.

Design: One hundred and ten healthy volunteers answered a questionnaire on their solar exposure habits and vitamin D intake and delivered one blood sample for quantification of vitamin D level (serum 25-hydroxyvitamin D (25(OH)D) concentration) during December 2007-January 2008. At the end of the winter we screened for the occurrence of respiratory infections and sought associations with vitamin D status.

Seasonal variations of cancer incidence and prognosis.

The overall death rates are highest in the winter season in many countries at high latitudes. In some but not all countries, this is also true for more specific diseases such as cancer, cardiovascular diseases and influenza. For internal cancers we find no consistent, significant seasonal variation, neither of incidence nor of death rates.

Vitamin D status in Norwegian children and adolescents with excess body weight.

Objectives: The prevalence of childhood and adolescent obesity has increased during the past decades. A high body mass index (BMI) is associated with a low vitamin D status. The purpose of this study was to determine the prevalence of vitamin D deficiency and insufficiency in Norwegian children and adolescents with excess body weight.

Serum 25-hydroxyvitamin D is a predictor of serum 1,25-dihydroxyvitamin D in overweight and obese patients.

Recent research suggests that 1,25-dihydroxyvitamin D [1,25(OH)(2)D], a steroid hormone that regulates calcium homeostasis, may also play a role in the development and progression of cancer, multiple sclerosis, cardiovascular, and other diseases. Decreased serum 1,25(OH)(2)D concentrations are often observed in overweight and obese patients. However, little is known about the factors that may influence 1,25(OH)(2)D renal synthesis, because it is generally accepted that serum 1,25(OH)(2)D concentration is strictly regulated by parathyroid hormone and serum concentrations of calcium and phosphorus.

The seasonality of pandemic and non-pandemic influenzas: the roles of solar radiation and vitamin D.

Objectives: Seasonal variations in ultraviolet B (UVB) radiation cause seasonal variations in vitamin D status. This may influence immune responses and play a role in the seasonality of influenza.

Methods: Pandemic and non-pandemic influenzas in Sweden, Norway, the USA, Singapore, and Japan were studied.

Obesity and increased risk of cancer: does decrease of serum 25-hydroxyvitamin D level with increasing body mass index explain some of the association?

Low levels of vitamin D and excess body weight are both factors associated with increased risk of cancer. The increased risk seems to be proportional to the increase in BMI, and to decrease in serum 25-hydroxyvitamin D (25(OH)D) level. Our earlier investigations suggest that serum 25(OH)D levels decrease with increasing BMI.

Sunbeds as vitamin D sources.

The objectives of this work were: (1) To determine whether repeated exposures to small doses from a commercial sun bed (Wolff Solarium Super Plus 100 W) over 5 weeks gave less vitamin D than repeated exposures to twice as large, but still nonerythemogenic, doses. (2) To investigate whether the contribution to the vitamin D status from such sessions of exposures was dependent on the baseline status before the start of the sessions. (3) To determine the decay rate of the induced increment of vitamin D.

The dependency of vitamin D status on body mass index, gender, age and season.

Background: Obesity is a rapidly growing health problem in most developed countries. Excess body weight is a risk factor for many somatic and even psychological disorders, including cardiovascular disease, type 2 diabetes mellitus, osteoarthritis and several cancer types. Recently, overweight and obesity have been shown to be related to low vitamin D status.

Solar radiation, vitamin D and cancer incidence and mortality in Norway.

Solar radiation is of fundamental importance for human development and health: On the one hand, too much of it can lead to skin ageing and skin cancer, whilst on the other, too little of it can result in vitamin D deficiency, and, thereby lead to high incidence and poor prognosis of internal cancer as well as a number of other diseases. The following data, mostly from Norway, will be reviewed: Variation of ambient solar ultraviolet radiation (UV) and vitamin D status with season and latitude, variation of incidence rates and prognosis of skin cancer and variation of prognosis of internal cancer with latitude and season. In short, the following issues are discussed: 1) Vitamin D level varies with season, but probably not with latitude in Norway, because of an increased intake of vitamin D in the north; 2) Skin cancer incidence rates increase from north to south, as do annual fluence rates of UV radiation, while there seems to be a slight improvement in prognosis from north to south; 3) Prognosis of internal cancer is best for cases diagnosed in the seasons with the best vitamin D status, i.

Sun and sun beds: inducers of vitamin D and skin cancer.

Solar radiation is both the main cause of all types of skin cancer, including cutaneous malignant melanoma (CMM), and the main source of vitamin D accompanied by its beneficial effects. The dilemma lies in that increased sun exposure could lead to an increase in skin cancers and yet is necessary for the better prognosis of internal cancers. Solar radiation varies in intensity and spectral composition with geographic location and time.

The vitamin D status among Tibetans.

UVB from the sun and intake from food are the only human sources of vitamin D. Tibet is a unique region for comparisons of these sources: (1) it lies at a low latitude and at a high altitude and has very large annual fluences of UVB; (2) the traditional Tibetan food is poor in vitamin D. Blood samples were taken from 63 persons of different age, with different occupations and staying at different places.

Seasonal variation of 1,25-dihydroxyvitamin D and its association with body mass index and age.

Under most normal conditions the serum level of 1,25-dihydroxyvitamin D is constant throughout the year, due to tight biochemical regulation. In contrast to this, the level of 25-hydroxyvitamin D is variable through the year, being largest in late summer, due to photosynthesis in the skin. The vitamin D status is usually assessed by measuring the level of the latter vitamin D derivative, rather than that of the presumably most active derivative 1,25(OH)2 vitamin D.

Colon cancer: prognosis for different latitudes, age groups and seasons in Norway.

The survival of colon cancer patients in Norway, as determined three years after diagnosis, is dependent on the season of diagnosis. This has been attributed to seasonal variations of the vitamin D status. Since solar radiation and food are the human sources of vitamin D, we divided Norway in three regions: The southeast region with a high annual dose of ultraviolet (UV) to the population, as evidenced by a high incidence rate of squamous cell carcinoma of the skin (SCC), the midwest region and the north region with low annual UV doses.

Prostate cancer survival is dependent on season of diagnosis.

Background: We have earlier found that the prognosis for several cancers is dependent on season of diagnosis. More recently, both prostate cancer incidence and mortality have been shown to increase with increasing latitude, which probably relates to photosynthesis of vitamin D.

Methods: The 3 year survival of prostate cancer patients has been analyzed with the Cox regression method for two age groups at different latitudes in Norway.

Changes in risk of death from breast cancer with season and latitude: sun exposure and breast cancer survival in Norway.

The Norwegian counties can conveniently be divided in three groups with different annual UV exposures and different incidence rates of squamous cell carcinoma (SCC) of the skin. In view of the hypothesis that latitude and season of diagnosis may play a role for breast cancer progression, the prognosis of breast cancer as determined for summer and winter diagnosis, were evaluated in the three residential regions. Two age groups were analysed separately (stratification at 50 years).