No need to delay pregnancy after miscarriage

Women who have had a miscarriage do not need to wait before trying to get pregnant again, say doctors.

A study by the University of Aberdeen of 30,000 women found that conceiving within six months offered the best chance for a healthy pregnancy.

The findings, published in the British Medical Journal, counter international guidelines that women should wait at least six months before trying again.

Doctors said the study would help them reassure and advise patients.

The researchers looked at data between 1981 and 2000 relating to women who had a miscarriage in their first pregnancy before going on to becoming pregnant again.

Women who conceived within six months were less likely to have another miscarriage, termination or ectopic pregnancy, the figures showed.


AdvertisementReport author Dr Sohinee Bhattacharya: "There are no physiological reasons why you should delay"
Also, among those who went on to give birth, conceiving within six months was associated with reduced risk of Caesarean birth, a premature delivery or a low birthweight baby compared with those women who had conceived between six months and a year.

Around one in five pregnancies ends in miscarriage before 24 weeks, a risk that increases with age.

Fertility

Study leader Dr Sohinee Bhattacharya, a lecturer in obstetric epidemiology, said current World Health Organization guidelines recommend that women delay by at least six months.

The NHS Choices website advises waiting three months to give women time to come to terms with the loss and for their menstrual cycle to re-establish itself.

But Dr Bhattacharya said that for older women, who are more at risk of miscarriage, a delay may actually hamper their chances of a successful pregnancy.

"Women wanting to become pregnant soon after a miscarriage should not be discouraged.

"If you're already over 35, I would definitely advise to try again within six months as age is more of a risk than the interval between pregnancies."

The only reason women may need to delay is if they have had a complication such as infection, she advised.


AdvertisementNo need to delay pregnancy after miscarriage
It is not clear why waiting longer than six months may be associated with more risk.

One theory is that underlying fertility problems may get worse with time.

Another possibility is that women trying for another baby shortly after a miscarriage may be highly motivated to stick to a healthy lifestyle.

Dr Tony Falconer, president-elect of the Royal College of Obstetricians and Gynaecologists, said the study showed women did not have to worry about trying again once they are physically and emotionally ready.

"It may be worth taking this opportunity to talk to your GP about anything you can do to prepare for a pregnancy," he said.

Professor Steve Field, chairman of the Royal College of GPs, said: "Miscarriages are a very traumatic event for prospective mums-to-be, and this new evidence will help health professionals reassure patients and enable them to give some good news and hope to patients at a time when they are often very anxious and under great stress."

Mary Newburn, head of research and information at parenting charity NCT, said: "It will be very reassuring to many women planning a pregnancy in their 30s or 40s to know that if they miscarry they do not need to wait before conceiving again."

New throat surgery 'a success'

Pioneering surgery to rebuild an 11-year-old boy's windpipe using his own stem cells has been hailed a success as he prepares to leave hospital.

Ciaran Finn-Lynch became the first child in the world to undergo the pioneering trachea transplant in March.

Ciaran, who is originally from Castleblayney, County Monaghan, is now due to return to his home in London.

Ciaran was born with Long Segment Tracheal Stenosis, which leaves sufferers with a very narrow windpipe.

Doctors at Great Ormond Street Hospital in London took stem cells from his bone marrow and injected them into a donor windpipe.

They implanted the organ and allowed the stem cells to transform themselves in his own body.

By using his cells, doctors hoped to avoid the potential problem of Ciaran's immune system rejecting the organ.

Great Ormond Street revealed on Thursday that the transplant, carried out four weeks ago was considered a success after doctors proved the blood supply had returned to the trachea.

Ciaran's parents, Colleen and Paul, now hope to take him home for the first time since November.

They said the last few months had been a "rollercoaster" and paid tribute to the surgeons who saved their son.

Operation

He underwent major surgery to reconstruct his airways but, at the age of two-and-a-half, a metal stent used to hold his airway open eroded into his aorta, a major artery.


AdvertisementProfessor Martin Birchall: "It could replace transplantation"
He went through more surgery, including two attempts to rebuild his airway, and finally left hospital after eight months.

Ciaran lived a full and active life until November last year when a stent again started to erode, causing a "massive bleed".

As options for Ciaran ran out, his specialists turned to stem cell treatment.

The surgery had been tried in Spain in 2008 on mother-of-two Claudia Castillo - the first person to receive a transplant organ created from stem cells - but Ciaran was to be the first child.

Ciaran was operated on in March, just four weeks after a donor trachea was found in Italy, and now doctors have confirmed his new windpipe is working well.
We didn't have much choice when it came to the operation," his mother Colleen said.

"If Ciaran had one more bleed I don't think he would have made it."

She said they had "100% faith" in the transplant team, led by Great Ormond Street's Professor Martin Elliott.

She said Ciaran's recovery had been "up and down" but he kept his spirits up.

"Because it's so new, nobody knows what's ahead, or how long his full recovery is going to be, but we are on the right road now," she said.

Ciaran, who turned 11 last month, is looking forward to going home and is likely to return to school in September.

A keen drummer, he is most excited about being able to play in his band again, and even started practising with a lesson in the hospital's intensive care unit recently.

Prof Elliott said the transplant team was "delighted" Ciaran could go home.

"He is a wonderful boy who has become a great friend to us all, and he and his infinitely patient family have charmed us all," he said.

"His recovery has been complicated, as one might expect for a new procedure, and we have kept him under close surveillance, hence the length of time he has been here.

"It is wonderful to see him active, smiling and breathing normally. We are very proud of him."

He said Ciaran would need regular follow-ups to check on his progress and to learn what to expect for the next patient who may need the innovative therapy.

"The treatment offers hope to many whose major airways were previously considered untreatable or irreplaceable," Prof Elliott added.

Violent Dreams May Precede Brain Disease

Vivid, violent dreams can portend brain disorders by half a century, a new study finds. The result, reported in the August 10 Neurology, highlights how some neurological diseases may take hold decades before a person is diagnosed.

Spotting early warning signs of the disease may allow clinicians to monitor and treat patients long before the brain deteriorPeople with a mysterious sleep disturbance called REM sleep behavior disorder, or RBD, experience a sudden change in the nature of dreams. Dreams increasingly become more violent and frequently involve episodes in which an attacker must be fought off.

The normal muscle paralysis that accompanies dreams is gone, leaving the dreamer, who is most often male, to act out the dream's punches, twists and yells. In many cases, a person sharing the dreamer's bed can be injured.

Doctors used to think of RBD as an isolated disorder. But follow-up studies revealed that a striking number of these patients later develop neurodegenerative diseases, including Parkinson's disease and Lewy body dementia.


Many Patients With Sleep Behavior Disorder Later Develop Neurodegenerative Disorders
The exact figures vary, but some studies find that anywhere from 80 to 100 percent eventually get a neurodegenerative disorder.

"The consensus among all RBD researchers is that it's not a matter of if, but when," says sleep expert Carlos Schenck of the Minnesota Regional Sleep Disorders Center in Minneapolis, who was one of the first researchers to describe RBD. "Basically, the longer you follow these men, the more they will convert to a neurodegenerative disorder."

In the new study, neurologist Bradley Boeve of the Mayo Clinic in Rochester, Minnesota, and his colleagues wanted to know just how long the interval between RBD and a neurodegenerative disorder can be. "Everybody who sees patients with this knew it could go on for a long time," Boeve says, but nobody knew just how long.

Boeve and his team examined medical records of patients from the Mayo Clinic to identify people diagnosed first with RBD and then with a neurodegenerative disorder at least 15 years later.
ates. For Some Patients, Sleep Disorder First Noticed by Spouse
Of the 27 patients who fit the criteria (of which only three were women, reflecting the curious male predominance of RBD), the median interval between onset of the sleep disorder and of the neurological disorder was 25 years, the team found.

For six of these patients, Boeve says, the sleep disorder was first noticed by their spouse on their honeymoon or shortly afterward. In one case, RBD preceded Parkinson's disease by 50 years.

The researchers can't estimate how frequently this happens in the general population, because patients were selected to have a minimum interval of 15 years between the onset of RBD and diagnosis of neurodegenerative disease. But finding such long intervals between diseases was unexpected.

"In the neurodegenerative realm, we just don't know any other clinical manifestations that can start so far in advance," Boeve says. "There are so few other illnesses that can have a window of decades from one clinical manifestation to another."

The 50-year interval uncovered in the study is an "extraordinarily long and slow lag period," Schenck says. "That's the big news."

Such a long interval brings the hope that once a "mysterious and magical neuroprotective agent is identified," Schenck says, it could be used before the brain is damaged severely. Some researchers think that by the time dementia symptoms appear, it is already too late to undo the damage.

Key cholesterol genes finding 'may help treatment'

Ninety-five different genes which affect cholesterol levels in the blood have been identified by an international group of experts.

The research, published in the journal Nature, examined genetic information from over 100,000 people who took part in 46 previous studies.

It is known that high levels of harmful cholesterol in the blood can lead to heart disease.

Experts said the finding could help develop new treatments.

The genetic variants pinpointed by the studies - produced by experts from the US, Europe and Asia - include some linked to cholesterol metabolism and known targets of cholesterol-lowering drugs.

They appear relevant to European and non-European populations, the researchers said.

One of the studies used to do the research was the joint British Heart Foundation and Medical Research Council family heart study, which involved 2,000 UK families affected by premature heart disease.

Professor Peter Weissberg, medical director at the British Heart Foundation, said: "The findings in this study, that as many as 95 different genes seem to be involved in regulating cholesterol levels in the blood, illustrate just how complicated the biology is.

"A great deal more research is needed to understand precisely what these genes do and how they interact.

"Although this is just a first step down a long road, the good news is that the more we understand about cholesterol regulation, the more likely it is that new drugs will be developed to prevent heart disease," he said.

Sleep Clinic Helping PTSD Sufferers

Chemical link to testicular cancer probed

Scientists hope to prove whether common environmental chemicals, such as those used to make plastics, are to blame for rising testicular cancer rates.

Experts suspect that exposure while in the womb might explain why the rate of this cancer has doubled in 35 years.

The Edinburgh team told Human Reproduction such a study was only now possible because they had made a model to study the disease in development.

They will use mice harbouring human cells to test the theory.

Testicular cancer occurs in young men, but doctors have known for some years that the abnormal changes that lead to testicular cancer happen in the first few months that the foetus is growing
But because these changes occur during early pregnancy, when there is no means of studying the foetal testes, doctors do not know how and why these changes occur.

Researchers are fairly certain there must be an environmental cause because the rate of the cancer has increased so rapidly.

According to Professor Richard Sharpe, of the Medical Research Council's Human Reproductive Sciences Unit, one theory is that the changes are caused by pregnant women being exposed to environmental chemicals such as phthalates, which are used in many different household items, including plastic furniture and packaging.

But because the cancers only develop 20-40 years after the patient is born, it has been hard for doctors to discover what happened in foetal development to cause this to happen, especially when trying to establish if their mothers were exposed to phthalates or other environmental chemicals to establish a causal relationship.

Mouse model

Now the MRC researchers have developed a model in which early human foetal testis development can be studied and manipulated experimentally to establish once and for all if exposure to environmental chemicals is a likely culprit.

Prof Sharpe's team has grafted testis tissue from aborted foetuses under the skin of mice. The germ cells in the testes are at the critical stage when any faults in their development can result in changes which make them pre-cancerous.

The researchers will expose the mice to phthalates or other environmental chemicals to see if this induces changes in the foetal germ cells that would predispose them to develop into a cancer.

Prof Sharpe said: "We are choosing to study phthalates first for several reasons, because we know that in the test-tube they can affect foetal human germ cells. They are also the most ubiquitous of environmental chemicals. We are all exposed to them."

Phthalates are used to make plastic flexible, and so can be found in carpets, wall boards, car upholstery and fittings and certain cosmetics and pharmaceutical drugs.

However, Prof Sharpe said that there was uncertainty about whether phthalate effects on the foetus in animal models were relevant to humans.

He said: "This is one of the critical unresolved questions as to whether phthalates pose a risk to human health or not.

"It's a huge industry. These compounds are literally part of the fabric of our modern society so they cannot easily be banned or removed without having widespread effects on everyday life. We need to know for sure if these compounds are harmful or not. The hope is that our studies can resolve this one way or another."

The researchers say that if phthalates do cause effects on human foetal germ cells they could know within a year. If the chemicals are not responsible it could take much longer to conclusively disprove any link.

Fit heart can slow brain ageing, US researchers say

Keeping your heart fit and strong can slow down the ageing of your brain, US researchers say.

A Boston University team found healthy people with sluggish hearts that pumped out less blood had "older" brains on scans than others.

Out of the 1,500 people studied, the team observed that the brain shrinks as it ages.

A poor cardiac output aged the brain by nearly two years on average, Circulation journal says.

The link was seen in younger people in their 30s who did not have heart disease, as well as elderly people who did.

Lead researcher Dr Angela Jefferson said: "These participants are not sick people. A very small number have heart disease. The observation that nearly a third of the entire sample has low cardiac index and that lower cardiac index is related to smaller brain volume is concerning and requires further study."

The participants with smaller brain volumes on magnetic resonance imaging did not show obvious clinical signs of reduced brain function.

But the researchers say the shrinkage may be an early sign that something is wrong.

More severe shrinkage or atrophy occurs with dementia.

Dr Jefferson said there were several theories for why reduced cardiac index - how much blood the heart pumps out relative to body size - might affect brain health.

For example, a lower volume of blood pumping from the heart might reduce flow to the brain, providing less oxygen and fewer nutrients needed for brain cells.

"It is too early to dole out health advice based on this one finding but it does suggest that heart and brain health go hand in hand," she said.

Experts say a person's cardiac index is fairly static - meaning it would be difficult to change it if it were low, without doing pretty intensive exercise training.

Dr Clinton Wright, a brain and memory expert from the University of Miami, said: "Whether lower cardiac index leads to reduced brain volumes and accelerates neurodegeneration on an eventual path to dementia is not yet clear.

"To address the health needs of our ageing population, a better understanding of the links between cardiovascular disease and brain structure and function will be required."

The Boston School of Medicine team will now continue to study the individuals in the trial to see if and how the brain changes affect memory and cognitive abilities over time.

Two Die in Florida From Eastern Equine Encephalitis

TAMPA, Fla. (Reuters) Jul 30 - Two Florida residents have died from Eastern equine encephalitis, a mosquito-borne disease that is rare among humans but has infected a rising number of horses in the state, health officials said on Friday.

Both deaths were in the Tampa area, where a woman died on July 1 and an infant died on Wednesday, the Hillsborough County Health Department said. There is no vaccine for humans.

"It's a fairly rare disease," said Steve Huard, spokesman for the Hillsborough health department.

Only a few human cases a year are reported in the United States, mostly in Atlantic and Gulf coast areas, according to the U.S. Centers for Disease Control and Prevention. But the disease kills 33% of its victims and survivors often have significant brain damage, the CDC said.

Hillsborough County has issued a mosquito-borne illness alert and sent a plane to spray pesticides to kill mosquitoes that breed in standing water, Huard said.

Eastern equine encephalitis outbreaks are not uncommon among horses in Florida during the wet summer months when mosquitoes proliferate.

Sixty cases have been reported among Florida horses this summer in several dozen counties, Florida Agriculture and Consumer Services Commissioner Charles Bronson said.

Two cases of West Nile disease, another mosquito-borne viral disease, have also been reported among horses in Florida, though the CDC said the state has reported no human cases.

West Nile disease is usually mild in humans and most who contract it have no symptoms, although it killed 32 people in the United States last year.

Mosquitoes carry the viruses that cause both diseases and can transmit them to both horses and humans, but horses do not transmit the viruses to people.

Bronson urged horse owners to get their animals vaccinated against both.

"In the vast majority of cases we have seen this year, the horses either had no vaccinations at all or they were not current," Bronson said.

"We are seeing increases in mosquito populations and, since mosquitoes are the carriers of both these diseases, it's likely the situation is going to get worse before it gets better."

Eastern Equine Encephalitis kills 90% of infected horses, while West Nile virus has a mortality rate in horses of about 30%. Signs of the viruses include fever, listlessness, stumbling, circling and coma.

While the incidence of both diseases is down from levels seen earlier in the decade, the toll for 2010 continues to rise among horses, Bronson said.

Florida has also seen a resurgence of dengue fever, another viral disease transmitted by mosquitoes, in southern Florida after a 75-year absence from the state.

Dengue is common in Central America and the Caribbean and the hemorrhagic form of the disease can kill humans, although no recent dengue deaths have been reported in the continental United States.

Health officials urged residents to use mosquito repellents, wear protective clothing and avoid being outside at dawn and dusk, when mosquitoes are most active.

Meat Preservatives Linked to Bladder Cancer?

High intake of ingredients known as nitrite and nitrate added to processed meats to aid preservation may be tied to bladder cancer -- but the relationship appears to be tentative, researchers say. In a study that followed more than 300,000 men and women for seven years, dietary nitrite and nitrate, as well as nitrite alone, were associated with an increased risk of bladder cancer among individuals with the highest consumption of processed meat -- but the connection was of borderline statistical significance, according to Amanda J. Cross of the National Institutes of Health and colleagues. In other words, the findings may have more to do with chance alone than with an actual causal link. Consumption of processed meat itself was not associated with an increased risk of bladder cancer, Cross and colleagues reported in the journal Cancer. "I think we should approach these modest results with caution," Dr. Shilajit Kundu, chief of urologic oncology at Northwestern Memorial Hospital, said in an interview with MedPage Today. Kundu was not involved in the study. Nathan Bryan of the University of Texas, who also was not involved in the study, had similar concerns. "There is not one single bit of data presented that is statistically significant by conventional statistical rules with 95 percent confidence," he said in an email to MedPage Today and ABC News. "With over 300,000 subjects, statistical significance should not be a problem if there is a clear and indisputable association." Researchers suspect that meat could be involved in bladder cancer due to compounds related to cooking and processing, including nitrates, nitrites, heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs). Nitrate and nitrite are added to processed meat for preservation as well as enhancement of color and flavor. PAHs and HCAs can form during cooking. These compounds and their metabolites are excreted through the urinary tract, which could lead to the development of cancer through contact with the cells lining the bladder or through systemic exposure, the researchers said. Yet evidence from prospective studies of meat and bladder cancer has been inconsistent. So the researchers looked at data 300,933 patients in the NIH-AARP Diet and Health Study, which included a food frequency questionnaire. Using various databases of nutritional information, they estimated intakes of nitrate, nitrite, HCAs, and PAHs. Over seven years of follow-up, there were 854 cases of transitional cell bladder cancer. The researchers found that, compared with those who ate the least amounts of red meat those who ate the most had a 22 percent higher risk of bladder cancer, though the finding was of borderline statistical significance. The researchers said the relationship was driven by consumption of processed red meats. However, there was no association between bladder cancer and white meat or processed meat itself. There was also no association between bladder cancer and beef, bacon, hamburger, sausage, or steak -- but the researchers did find a positive association for cold cuts made from red meat. While bladder cancer and nitrate were not linked, there was an association with dietary nitrite. Those with the highest nitrite consumption had an increased risk compared with those with the lowest intake -- but again this finding did not reach the traditionally accepted level of statistical significance. Still, Cross and colleagues said the findings "support the hypothesis of 'N-nitroso compounds' involvement in bladder carcinogenesis, as processed meat also provides amines and amides necessary for the endogenous formation of [these compounds]." The researchers said the findings "provide modest support" for an increased risk of bladder cancer associated with nitrite plus nitrate and PhIP, but acknowledged that the study was limited by a lack of information on urination frequency and bladder infections and limited data on beverage intake. The authors called for further research into different dietary sources of nitrate and nitrite to determine which may have the strongest association with bladder cancer. "Additional research is needed to confirm our findings of a possible increased risk of bladder cancer with intake of red meat and especially for PhIP, as prospective investigations of meat-related mutagens and this malignancy are lacking," they added. Kundu told MedPage Today that "a lot of work still needs to be done before we can say that red meats or processed meats should be cut out all together."

Cardiotoxicity of Childhood Cancer Treatments Affects Many Young Adult Survivors

August 2, 2010 — More than one fourth of childhood cancer survivors treated with potentially cardiotoxic therapies have an abnormal cardiac function as young adults, according to new research.

Helena J. van der Pal, MD, with the Department of Medical Oncology, at the Emma Children's Hospital/Academic Medical Center, Amsterdam, the Netherlands, and colleagues reported the findings in the June 26 issue of Archives of Internal Medicine.

According to Dr. van der Pal and colleagues, studies evaluating cardiovascular toxicity in this setting have produced variable results. "Several population based studies observed a 6- to 8-fold increased mortality owing to CVD [cardiovascular disease] among childhood cancer survivors compared with the general population," they note.

To evaluate the incidence of cardiovascular toxicity further, they conducted echocardiograms in 525 young adults who had survived at least 5 years after treatment with potentially cardiotoxic therapies (anthracyclines, cardiac irradiation, high-dose cyclophosphamide, or high-dose ifosfamide). Of those, 514 were assessed for left ventricular shortening fraction (LVSF).

Overall, the median LVSF was decreased by 33.1% (range, 13.0% - 56.0%), and 27% of patients were defined as having subclinical cardiac dysfunction, defined as LVSF of less than 30%.

On multivariate analysis, the strongest predictors of subclinical cardiac dysfunction were higher cumulative anthracycline dose, thoracic irradiation, and diagnosis at a younger age.

High-dose cyclophosphamide and ifosfamide were not associated with a reduction of LVSF, whereas vincristine sulfate was associated with a trend towards decreased cardiac function (P = .07). When adjusted for antitumor efficacy, epirubicin hydrochloride was comparable to doxorubicin in cardiotoxicity, and both seemed more cardiotoxic than daunorubicin hydrochloride.

"Continued monitoring of all childhood cancer survivors treated with potentially cardiotoxic therapy with or without subclinical cardiac dysfunction is necessary to identify (childhood cancer survivors) who could possibly benefit from early treatment, which could avoid further deterioration of cardiac function," the authors conclude.

The study was supported by the Foundation of Pediatric Cancer Research, Amsterdam, the Netherlands. The study authors have disclosed no relevant financial relationships.

Herpes virus used to treat cancer

Doctors say they have used a genetically engineered herpes virus to treat successfully patients with head and neck cancer.

A London hospital trial of 17 patients found that use of the virus alongside chemotherapy and radiotherapy helped kill the tumours in most patients.

It works by getting into cancer cells, killing them from the inside, and also boosting the patient's immune system.

Further trials are planned for later in the year.

Head and neck cancer, which includes cancer of the mouth, tongue and throat, affects up to 8,000 people every year in the UK.

Study leader Dr Kevin Harrington, who is based at the Institute of Cancer Research in London, said current treatments were effective if the cancer was picked up early but that many patients were not diagnosed until it was more advanced.

The herpes virus, which is also being tested in patients with skin cancer, is genetically manipulated so that it grows inside tumour cells but cannot infect normal healthy cells.

Once there it has a triple effect - it multiplies, killing tumour cells as it does so, it is engineered to produce a human protein that activates the immune system and it also makes a viral protein that acts as a red flag to immune cells.

'Potential weapon'

In the 17 patients injected with the virus, in addition to their standard treatment, at the Royal Marsden Hospital, 93% showed no trace of cancer after their tumour had been surgically removed.

More than two years later, 82% of patients had not succumbed to the disease.

Only two of 13 patients given the virus treatment at a high dose relapsed, the journal Clinical Cancer Research reported.

There were no safety concerns with use of the virus, the researchers said, and it is hoped the virus could one day be used to fight other types of cancer.

"Around 35 to 55% of patients given the standard chemotherapy and radiotherapy treatment typically relapse within two years, so these results compare very favourably," said Dr Harrington.

He is now planning a trial comparing the viral treatment with the standard treatment in people newly diagnosed with head and neck cancer.

Dr Alison Ross, senior science information officer at Cancer Research UK, said it would be some time before the treatment could be used in patients as it still needed to be tested directly against standard treatment.

But she added: "This small study highlights the potential of using genetically modified viruses as a weapon to fight cancer."

Family, Friends Help You Live Longer

Humans are social animals, and most of us treasure our relationships with family and friends.

An emerging line of research suggests that relationships can keep us healthier. And a new study finds those social connections may also help us live longer.

This new study combined a large number of previous studies and concluded that a lack of social interactions ranks right up with smoking, obesity, and alcoholism as a risk factor for death.

Researchers from Brigham Young University analyzed 148 studies with a total of some 300,000 participants, tracking their social relationships and whether they survived to the end of their particular study, which averaged about seven years.
"Those who scored higher on those measures of social relationships were 50 percent more likely to be alive at that follow-up than people who scored low on those measures," said Professor Julianne Holt-Lunstad, one of the authors of the study.

She pointed out several ways relationships can affect our health. They can help us cope with stress. They can help us maintain healthy habits like eating well, exercising or seeing a doctor. And there's increasing research that shows a direct but poorly-understood link between relationships and physiological processes in the body.

"So for instance, our relationships have been linked to lower blood pressure, better immune functioning, and even inflammatory processes that are implicated in a number of diseases," said Holt-Lunstad. "And so our relationships can influence our health in a variety of ways that are all very important."

Even though Holt-Lunstad and her colleagues looked at almost 150 different scientific studies, most of them didn't assess the quality of the relationships.

"And certainly relationship quality matters, and not all relationships are entirely positive," she conceded. "And so it's possible that the effects that we have reported may be a conservative estimate, and that the odds of survival associated with high-quality relationships may actually be larger."

Speaking via Skype, Julianne Holt-Lunstad said her research suggests that policy makers need to consider relationships as a health issue. So just as no-smoking zones have expanded over the years, she suggests that city planners, for example, should consider whether their decisions might promote or hinder the development of personal relationships.
Julianne Holt-Lunstad's study is published in the journal PloS Medicine.