Don't blame job stress for high blood pressure

By Anne Harding

NEW YORK (Reuters Health) – The notion that being stressed out on the job causes high blood pressure doesn't hold up, according to a new analysis of studies involving more than 100,000 people.

"There's no doubt that in the moment stress raises blood pressure," the study's author, Dr. Samuel J. Mann of Weill Cornell Medical College in New York, told Reuters Health. But there's virtually no evidence, he said, that such stress leads to chronic high blood pressure, or hypertension. "They've been trying to prove that for 40 years."

While job stress can certainly affect health in some ways, he added, blood pressure isn't one of them. "There's a robust relationship between job stress and things like tension headaches, anxiety, depression," Mann said. "If somebody is having all that and having headaches every day, can't sleep and is anxious, then that's a person who should change his job."

Mann conducted his review after the 2003 publication of a well-designed study by French researchers that found no link between job stress and hypertension.

In the current analysis, he looked at 48 studies claiming to support such an association. Many, Mann found, had serious flaws – for example, only basing the findings on diastolic pressure (the lower number in a blood pressure reading) rather than systolic pressure.

Others only found a stress-hypertension association in a small subgroup of individuals studied, and such subgroups varied from study to study. Still others looked at several variables measuring stress and found only one of them was linked, weakly, with hypertension, and played up this finding rather than the negative ones. "After decades of research," Mann concludes in his report in Current Hypertension Reviews, "the evidence for a relationship between job stress and blood pressure is weak."

Studies have tied stress to heart disease, Mann noted, but hypertension is not likely to be the contributing link. Instead, he added, stress might boost high blood pressure risk by leading people to overeat, gain weight and abuse alcohol.

While Mann says he's not categorically denying that job stress could cause hypertension in some people, its role is likely small. About 40 percent of hypertension is due to genetics, and another 40 percent to overweight, poor diet, salt intake and lack of exercise – leaving about 20 percent available for other causes, he explained.

"If somebody has hypertension and they don't like their job, medically there's no reason to tell them to quit their job because it adversely affects their blood pressure."

SOURCE: Current Hypertension Reviews, May, 2006

Reuters 2006. All Rights Reserved

Britain’s population tops 60 million for first time

By Maxine Fritch, Social Affairs Correspondent

The population of the United Kingdom has passed 60 million for the first time, with the fastest growth rate in more than 40 years.

Migration was the single biggest factor behind the rise in the number of people living in Britain, according to official figures released by the Office for National Statistics (ONS). But far from creating economic problems, experts said the increase in immigrants was propping up the birth rate and could allay concerns that the ageing population was leading to a demographic time bomb.

The ONS figures showed that, in July last year, the population of the UK stood at 60.2 million, with 375,000 more people than the previous year. The increase represented the biggest rise in numbers since 1962 and indicated a growth rate of 0.6 per cent, compared with an average rate of 0.3 per cent between 1989 and 1999.

Analysts said the main reason behind the record growth in numbers was the increase in international migration. For the purposes of the population estimates, only people leaving or coming into the UK for more than a year are counted, making the figures different from those released by the Home Office earlier this week.

In the year to July 2005, the number of migrants coming into the UK rose by 11 per cent compared with the previous 12 months, with an extra 59,000 foreign nationals entering the country. Migration from the UK to other countries fell by 2 per cent, with 8,000 fewer British people leaving for a new life abroad.

The net increase in migration – the difference between those leaving Britain and those coming in – rose from 167,000 in 2003 – 2004 to 235,000 last year; the highest change since records were first produced on the current basis in 1991. An influx of migrants from countries that joined the European Union in 2004, such as Poland, Lithuania and the Czech Republic, accounted for the bulk of the rise. In the year before they acceded to the EU, 10,000 people from the eight new eastern European member states entered the UK. In the first 12 months of their member- ship, 74,000 entered the UK with the intention of staying at least a year, making up a third of all net migration into Britain.

The influx of a new generation of mainly younger migrants has also helped to increase the difference between the number of births and deaths, known as natural change. According to the ONS statistics, there were 10,000 more births and 12,000 fewer deaths in the year to mid-2005 com­pared with the previous 12 months. Peter Goidblatt of the ONS said: "Had there been no migration whatever, the population would have had fewer births. The numbers of births would not have gone up."

The number of people of working age in the population also rose by 0.8 per cent, from 37.1 million to 37.4 million within the same period. But the population is continuing to age, with the number of people over 85 up by 6 per cent last year to a record of 1,176,000.

The proportion of younger people is declining, with the under-16 pop­ulation making up 19.3 per cent of the UK compared to 20.7 per cent 10 years ago.

The Independent

Friday, 25 August, 2006