Inflammation, vitamin D and dendritic cell precursors in chronic kidney disease.

Decreased blood dendritic cell precursors (DCP) count is linked with atherosclerotic disease, while reduction of circulating DCP is also seen in patients with chronic kidney disease (CKD). As poor vitamin D status could be linked to a compromised innate immune response, we hypothesized that vitamin D status might be involved in the decrease in circulating DCP in CKD. Moreover, the potential role of inflammation was considered. Circulating myeloid (mDCP), plasmacytoid (pDCP) and total DCP (tDCP) were analysed using flow cytometry in 287 patients with CKD stage 3. Serum 25(OH)D and 1,25(OH)2D levels were measured using enzyme-linked immunosorbent assays (ELISA), interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α using cytometric bead array, C-reactive protein (CRP) using a high-sensitivity (hs) ELISA. Contrary to our hypothesis, there was no association between vitamin D levels and DCP, although their number was decreased significantly in CKD (P < 0·001). Instead, mDCP (r = -0·211) and tDCP (r = -0·188,) were associated slightly negatively with hsCRP but positively with the estimated glomerular filtration rate (eGFR, r = 0·314 for tDCP). According to multivariate linear regression, only higher hsCRP concentration and the presence of diabetes mellitus had a significant negative influence on DCP count (P < 0·03, respectively) but not vitamin D, age and eGFR. A significant impact of vitamin D on the reduction of circulating DCP in CKD 3 patients can be neglected. Instead, inflammation as a common phenomenon in CKD and diabetes mellitus had the main influence on the decrease in DCP. Thus, a potential role for DCP as a sensitive marker of inflammation and cardiovascular risk should be elucidated in future studies.

Health benefits of cycling: a systematic review.

The purpose of this study was to update the evidence on the health benefits of cycling. A systematic review of the literature resulted in 16 cycling-specific studies. Cross-sectional and longitudinal studies showed a clear positive relationship between cycling and cardiorespiratory fitness in youths. Prospective observational studies demonstrated a strong inverse relationship between commuter cycling and all-cause mortality, cancer mortality, and cancer morbidity among middle-aged to elderly subjects. Intervention studies among working-age adults indicated consistent improvements in cardiovascular fitness and some improvements in cardiovascular risk factors due to commuting cycling. Six studies showed a consistent positive dose-response gradient between the amount of cycling and the health benefits. Systematic assessment of the quality of the studies showed most of them to be of moderate to high quality. According to standard criteria used primarily for the assessment of clinical studies, the strength of this evidence was strong for fitness benefits, moderate for benefits in cardiovascular risk factors, and inconclusive for all-cause mortality, coronary heart disease morbidity and mortality, cancer risk, and overweight and obesity. While more intervention research is needed to build a solid knowledge base of the health benefits of cycling, the existing evidence reinforces the current efforts to promote cycling as an important contributor for better population health.

[Individually adapted counseling about physical activity in medical practice]. / Individuell adaptierte Bewegungsberatung in der Arztpraxis.

The risk to health posed by a sedentary lifestyle is a problem of our times. In contrast to the previous assumption that only fairly high-intensity sporting exercise undertaken over a minimum period of 20 min produces health-related benefits, recent studies have shown that even everyday activities (climbing stairs, brisk walking and cycling) can have a benedicial effects on health, particularly in those who take little exercise. So now the recommendation is: exercise of moderate intensity lasting 30 min at least 5 times a week, corresponding to an energy consumption of about 150 kacl/day or 1000 kcal/week. The results of experimental studies on sport and arthritis and sport and osteoporosis point to the advisability of taking up or maintaining an active sporting lifestyle. For one thing, it can be assumed that a moderate amount of movement does not increase the risk of developing arthritis: for another, sporting activity during early and late childhood produces a high maximum bone mass, therby delaying the development of osteoporosis in later life. The new guidelines on the extent and intensity of health-giving exercise make it easier to advocate exercise and sport for disease prevention and health promotion because they appear to implement. More difficult, however, is deciding on a suitable method for motivating inactive individuals to increase their level of physical activity. A model that has proved effective in smoking cessation programmes, and one that can also be applied to exercise counselling (transtheoretical model), can help in the selection of an appropriate counselling strategy. Depending on whether an individual is inactive, or sporadically or regularly active, each one employs his or her own strategies primarily to maintain this lifestyle. Assuming that the counselling is adapted to the level of activity, the patient's attitude and behaviour can be influenced both more effectively and more economically.