顯示具有 longer 標籤的文章。 顯示所有文章
顯示具有 longer 標籤的文章。 顯示所有文章

2011年8月20日 星期六

Black men survive longer in prison than out: study

By Genevra Pittman

NEW YORK | Thu Jul 14, 2011 5:42pm EDT

NEW YORK (Reuters Health) - Black men are half as likely to die at any given time if they're in prison than if they aren't, suggests a new study of North Carolina inmates.

The black prisoners seemed to be especially protected against alcohol- and drug-related deaths, as well as lethal accidents and certain chronic diseases.

But that pattern didn't hold for white men, who on the whole were slightly more likely to die in prison than outside, according to findings published in Annals of Epidemiology.

Researchers say it's not the first time a study has found lower death rates among certain groups of inmates -- particularly disadvantaged people, who might get protection against violent injuries and murder.

"Ironically, prisons are often the only provider of medical care accessible by these underserved and vulnerable Americans," said Hung-En Sung of the John Jay College of Criminal Justice in New York.

"Typically, prison-based care is more comprehensive than what inmates have received prior to their admission," Sung, who wasn't involved in the new study, told Reuters Health by email.

The new study involved about 100,000 men between age 20 and 79 who were held in North Carolina prisons at some point between 1995 and 2005. Sixty percent of those men were black.

Researchers linked prison and state health records to determine which of the inmates died, and of what causes, during their prison stay. Then they compared those figures with expected deaths in men of the same age and race in the general population.

Less than one percent of men died during incarceration, and there was no difference between black and white inmates. But outside prison walls, blacks have a higher rate of death at any given age than whites.

"What's very sad about this is that if we are able to all of a sudden equalize or diminish these health inequalities that you see by race inside a place like prison, it should also be that in places like a poor neighborhood we should be able to diminish these sort of inequities," said Evelyn Patterson, who studies correctional facilities at Vanderbilt University in Nashville, Tennessee.

"If it can be done (in prison), then certainly it can happen outside of prison," Patterson, who wasn't linked to the new work, told Reuters Health.

As in the general population, cancer and heart and blood vessel diseases were the most common cause of death among inmates -- accounting for more than half of deaths.

White prisoners died of cardiovascular diseases as often as expected and died of cancer slightly more often than non-prisoners.

Black inmates, by contrast, were between 30 and 40 percent less likely to die of those causes than those who weren't incarcerated. They were also less likely to die of diabetes, alcohol- and drug-related causes, airway diseases, accidents, suicide and murder than black men not in prison.

All told, their risk of death at any age was only half that of men living in the community.

For white men, the overall death rate was slightly higher -- by about 12 percent -- than in the general population, with some of that attributed to higher rates of death from infection, including HIV and hepatitis. When the researchers broke prisoners up by age, death rates were only higher for white prisoners age 50 and older.

"For some populations, being in prison likely provides benefits in regards to access to healthcare and life expectancy," said study author Dr. David Rosen, from the University of North Carolina at Chapel Hill.

But, he added in an email, "it's important to remember that there are many possible negative consequences of imprisonment -- for example, broken relationships, loss of employment opportunities, and greater entrenchment in criminal activity -- that are not reflected in our study findings but nevertheless have an important influence on prisoners' lives and their overall health."

For Rosen, one of the main messages from the study is the need to make the world outside of prison walls safer, and to make sure people living there have adequate access to healthcare.

SOURCE: bit.ly/o7a7st Annals of Epidemiology, online July 7, 2011.

2011年8月8日 星期一

Older women who take vitamin D3 may live longer

A woman checks a list of places to vote in Sao Paulo October 5, 2008. REUTERS/Rodrigo Paiva

A woman checks a list of places to vote in Sao Paulo October 5, 2008.

Credit: Reuters/Rodrigo Paiva

By Amy Norton

NEW YORK | Thu Jul 7, 2011 11:39am EDT

NEW YORK (Reuters Health) - Elderly women who take vitamin D3 supplements may have a small survival advantage over those who don't, a new research review concludes, although they also raise their risk of kidney stones.

The review of 50 clinical trials involving more than 94,000 elderly adults found that those randomly assigned to take vitamin D3 were six percent less likely to die during study periods averaging two years than participants given inactive pills or no treatment.

That reduced risk of death, researchers say, translates into 200 elderly adults having to take vitamin D3 for about two years in order to save one additional life.

Many questions remain, however. For one, the trials included mostly women, so it's not clear if men would stand to gain the same benefit.

Moreover, it's not clear why women given vitamin D3 had better survival odds -- or what form or dose of the vitamin might be best.

Many of the studies focused on elderly adults living in nursing homes, who are likely to be deficient in vitamin D, frail and at risk of falls.

Vitamin D is needed for healthy bones, and a number of studies have suggested that supplements may lower elderly adults' risk of falls and fractures -- which can prove fatal.

"These preventive effects could likely explain some or all of the mortality reduction we observed," Dr. Christian Gluud, the senior researcher on the new study, told Reuters Health in an email.

However, he said, more research is needed to understand why women who took vitamin D3 had a lower death rate.

Although Gluud's team looked at studies involving four different forms of vitamin D, they found that better survival was specifically linked to vitamin D3 (cholecalciferol), which is more potent and readily absorbed than vitamin D2 (ergocalciferol), the form often found in multivitamins.

But it's not clear whether that's because only vitamin D3 is effective, or because too few trials have tested D2 or other forms of the vitamin, according to Gluud, who works with the Cochrane Collaboration, an international research organization that evaluates medical evidence and published the current findings.

As for the optimal dose of vitamin D for elderly people's health, that too remains to be seen, Gluud said.

In their review, he and his colleagues saw a reduced risk of death with vitamin D3 doses of 800 international units (IU) or less. But, Gluud noted, few trials have tested higher doses.

The benefit his team found is, however, in line with current recommendations.

Last year, the Institute of Medicine (IOM), a scientific advisory panel to the U.S. government, said that most people need 600 IU of vitamin D per day, while adults older than 70 should strive for 800 IU.

Older people are at increased risk of vitamin D deficiency because their bodies are less efficient at producing the vitamin after exposure to the sun, and because their kidneys are less able to convert vitamin D to its active form.

But in its recommendations, the IOM also sought to temper some of the enthusiasm over vitamin D in recent years.

A flurry of studies has linked higher vitamin D intake to lower risks of everything from diabetes, to severe asthma, heart disease, certain cancers and depression.

The problem with those studies is that they were observational -- which means that researchers looked at people's vitamin D intake, or their blood levels of the vitamin, and whether they developed a given health condition. Those studies cannot prove cause-and-effect.

And the IOM said that, other than benefits for bone health, there is insufficient evidence that vitamin D thwarts any specific health condition.

So what should older adults do about vitamin D? They can follow the IOM recommendations on intake levels, and choose food sources of the vitamin -- including fatty fish like salmon and mackerel, and fortified dairy products and cereals.

As for vitamin pills, Gluud said that older adults can talk with their own doctors about whether that's a good idea.

He added that vitamin supplements should be seen as medications that could potentially affect your life expectancy in a positive or negative way.

"Always discuss any medication with your physician," Gluud advised.

The IOM set an upper limit for vitamin D intake, at 4,000 IU per day. Taking too much can lead to vitamin D toxicity, which causes symptoms like nausea, vomiting, constipation and poor appetite. It can also lead to kidney stones and, by raising calcium levels in the blood, heart rhythm disturbances.

In this study, Gluud's team found that vitamin D3 taken along with calcium raised elderly adults' risk of kidney stones by 17 percent.

Gluud said that more clinical trials are needed to compare the effects of different doses of vitamin D, and to study the health effects in elderly men and younger people.

There's also little known about whether the cost of widespread vitamin D use would be worth the benefit. But the vitamin is cheap -- at about $10 for a two-month supply.

SOURCE: bit.ly/qDuorP Cochrane Library, July 2011.