Sunday, January 31, 2010

Thursday, January 21, 2010

Experts: Sitting too much could be deadly

LONDON – Here's a new warning from health experts: Sitting is deadly.

Scientists are increasingly warning that sitting for prolonged periods — even if you also exercise regularly — could be bad for your health. And it doesn't matter where the sitting takes place — at the office, at school, in the car or before a computer or TV — just the overall number of hours it occurs.

Research is preliminary, but several studies suggest people who spend most of their days sitting are more likely to be fat, have a heart attack or even die.

In an editorial published this week in the British Journal of Sports Medicine, Elin Ekblom-Bak of the Swedish School of Sport and Health Sciences suggested that authorities rethink how they define physical activity to highlight the dangers of sitting.

While health officials have issued guidelines recommending minimum amounts of physical activity, they haven't suggested people try to limit how much time they spend in a seated position.

"After four hours of sitting, the body starts to send harmful signals," Ekblom-Bak said. She explained that genes regulating the amount of glucose and fat in the body start to shut down.

Even for people who exercise, spending long stretches of time sitting at a desk is still harmful. Tim Armstrong, a physical activity expert at the World Health Organization, said people who exercise every day — but still spend a lot of time sitting — might get more benefit if that exercise were spread across the day, rather than in a single bout.

That wasn't welcome news for Aytekin Can, 31, who works at a London financial company, and spends most of his days sitting in front of a computer. Several evenings a week, Can also teaches jiu jitsu, a Japanese martial art involving wrestling, and also does Thai boxing.

"I'm sure there are some detrimental effects of staying still for too long, but I hope that being active when I can helps," he said. "I wouldn't want to think the sitting could be that dangerous."

Still, in a study published last year that tracked more than 17,000 Canadians for about a dozen years, researchers found people who sat more had a higher death risk, independently of whether or not they exercised.

"We don't have enough evidence yet to say how much sitting is bad," said Peter Katzmarzyk of the Pennington Biomedical Research Center in Baton Rouge, who led the Canadian study. "But it seems the more you can get up and interrupt this sedentary behavior, the better."

Figures from a U.S. survey in 2003-2004 found Americans spend more than half their time sitting, from working at their desks to sitting in cars.

Experts said more research is needed to figure out just how much sitting is dangerous, and what might be possible to offset those effects.

"People should keep exercising because that has a lot of benefits," Ekblom-Bak said. "But when they're in the office, they should try to interrupt sitting as often as possible," she said. "Don't just send your colleague an e-mail. Walk over and talk to him. Standing up."

Tuesday, January 12, 2010

Monday, January 11, 2010

Renal and cardio-protective effects of direct renin inhibition: a systematic literature review

Journal of Hypertension
Issue: Volume 27(12), December 2009, p 2321–2331
Copyright: © 2009 Lippincott Williams & Wilkins, Inc.
Publication Type: [Meta-analyses]

aDepartment of Clinical Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
bGeorge Institute for International Health, University of Sydney, Sydney, Australia

Results: Fifty-two articles were included. Blood pressure reductions were generally insufficient using early generation DRIs. However, recent DRIs have greater blood pressure-lowering effects. Preclinical and clinical studies showed profound effects of DRIs on markers of renal function, including clear increases in renal plasma flow and reductions in albuminuria. These effects were observed either alone or in combination with other RAAS inhibitors and suggest potential large renal protective benefit. DRIs improved hemodynamic cardiovascular parameters, such as total peripheral resistance, arterial pressure and left ventricular mass index, to a similar extent as those observed with other RAAS inhibitors. Furthermore, addition of DRIs to optimal heart failure treatment resulted in further reductions in B-type natriuretic peptide.


Conclusions: Evidence from preclinical and clinical studies suggests that DRIs may have renal and cardiovascular effects beyond their ability to lower blood pressure. Results of ongoing hard outcome trials are awaited to definitively assess the renal and cardio-protective effects of these agents.

Do COX-2 inhibitors raise blood pressure more than nonselective NSAIDs and placebo? An updated meta-analysis. Chan, Clara, Reid, Christopher, Aw, Tai-

Journal of Hypertension
Volume 27(12) December 2009
(C) 2009 Lippincott Williams & Wilkins, Inc.

Conclusion: On the basis of this updated meta-analysis, coxibs appear to produce greater hypertension than either ns-NSAIDs or placebo. However, this response was heterogeneous, with markedly raised BP associated with rofecoxib and etoricoxib, whereas celecoxib, valdecoxib and lumiracoxib appeared to have little BP effect. The relationship of this increased risk of hypertension to subsequent adverse CV outcomes requires further investigation and prospective RCTs.