维多利亚·拉尼德文 刘春伶 刘建稳译

The benefits that come with owning a dog are clear—physical activity， support， companionship—but owning a dog could literally be saving your life. 養狗的好处不言而喻——活动身体，得到支持，相依为伴——而且养狗真的可以救命。

Dog ownership is associated with a reduced risk for cardiovascular disease and death， finds a new Swedish study published in the journal Scientific Reports.

For people living alone， owning a dog can decrease their risk of death by 33% and their risk of cardiovascular related death by 36%， when compared to single individuals without a pet， according to the study. Chances of a heart attack were also found to be 11% lower.

Multi-person household owners also saw benefits， though to a lesser extent. Risk of death among these dog owners fell by 11% and their chances of cardiovascular death were 15% lower. But their risk of a heart attack was not reduced by owning a dog.

“A very interesting finding in our study was that dog ownership was especially prominent as a protective factor in persons living alone， which is a group reported previously to be at higher risk of cardiovascular disease and death than those living in a multi-person household，” said Mwenya Mubanga， an author on the study and PhD student at Uppsala University.

As a single dog owner， an individual is the sole person walking and interacting with their pet as opposed to married couples or households with children， which may contribute to greater protection from cardiovascular disease and death， said the study.

Owners of hunting breeds， including terriers， retrievers， and scent hounds， are most protected from cardiovascular disease and death. However， owning any dog will reduce an owners risk of death， just to different extents， said Tove Fall， senior author of the study and Associate Professor in Epidemiology at Uppsala University.

The study looked at over 3.4 million Swedish individuals between the ages of 40 and 80 sampled from a national database and the Swedish Twin Registry over a 12-year study period.

“We know that dog owners in general have a higher level of physical activity， which could be one explanation to the observed results，” said Fall. This includes taking the dog out for a walk in any weather condition.

The findings also suggest increased social well-being and immune system development as additional reasons why dog ownership offers protection against cardiovascular disease and death.

One factor behind this may be because dogs bring dirt into homes and they lick you， which could impact your microbiome—the bacteria that live in your gut—and thus your health.

“It may encourage owners to improve their social life， and that in itself will reduce their stress level， which we know absolutely is a primary cause for cardiovascular disease and cardiac events，” said Dr. Rachel Bond， Associate Director of Womens Heart Health at Lenox Hill Hospital in New York City， who was not involved in the research.

More to be revealed

Fall believes that while their study provides strong evidence for the health benefits of dogs， their work is not done yet， since it does not answer why dogs achieve these results or why specific breeds seem to offer more protection.

Bond commented that owners of hunting breeds may be getting more exercise because these dogs are more active as opposed to small dogs who do not require as much exercise.

There are also other factors that still need to be considered， such as the owners personality and general physical health and activity.

“It is hard to say if there truly is a causal effect. This study in particular， excluded patients with heart disease in general， and we know that disabled people may be less likely to own a dog so that really raises the question if owning a dog leads to heart health or it is merely a marker for people who are more likely to have good heart health，” said Dr. Bond.

While Bond may not prescribe a dog as treatment for a patient， she said that she will not discourage owning or buying one， or expressing the benefits of owning one.

Benefits beyond Sweden

While the research was carried out in Sweden， Fall does believe it may also apply to other countries， including the US， since popular breeds and peoples attitudes toward dog care are similar.

However， some factors that may affect the results are the differences in climate and socio-economic backgrounds， noted Fall.

“We have a colder climate so we have indoor dogs where owners take their dogs out for a walk. In warmer climates， they could keep them in the yard and wont have to actively take them for a walk，” said Fall.

“I think it would be hard to take the data from Sweden and apply it to the US since we have a more diverse population. More studies should be obtained in the United States，” said Bond.

瑞典一項新研究发现，养狗可以降低心血管疾病的患病与死亡风险。该研究报告发表于《科学报告》杂志。

根据这项研究，同没养宠物的独居人士相比，养狗的独居人士死亡风险降低33%，心血管疾病引起的死亡风险降低36%，此外，心脏病发作几率降低11%。

非独居人士养狗也有益处，只是程度较小。此类养狗人士的死亡风险降低11%，心血管疾病引起的死亡几率降低15%。但养狗并没有降低他们心脏病发作的几率。

该研究报告的作者之一、乌普萨拉大学博士生姆韦尼娅·穆班加说：“我们研究中有个特别有意思的发现，即养狗对独居人士的保护作用特别明显，先前有报告说，独居人士患上心血管疾病和死亡的风险都高于非独居人士。”

该研究指出，相对于已婚夫婦或有孩子的家庭，对单身养狗人士来说，与狗狗散步和交流都须一力承担，这或许帮助他们更能免于心血管疾病和死亡。

养猎犬，包括?犬、寻回犬和嗅觉猎犬等品种的人，能够得到最好的保护，免于血管疾病和死亡。不过，养任何种类的狗都会降低养狗人士的死亡风险，只是程度有所不同。该项研究报告的主要作者、乌普萨拉大学流行病学副教授托弗·法尔如是说。

该研究历时12年，样本来自国家数据库和瑞典双胞胎统计所，样本容量为超340万瑞典人，年龄在40至80岁之间。

法尔说：“我们知道，一般来讲，养狗人士体力活动较多，这可能用以解释观察到的结果。”体力活动包括，不论何种天气，养狗人士都会出去遛狗。

研究结果还显示，养狗之所以能预防心血管疾病和死亡，还在于其可以提高社会幸福感，增强免疫系统。

这背后一个因素，可能是因为宠物狗把尘土带到家里，还会舔主人，这样可能影响其肠道菌群——生活在肠道里的各种细菌——进而对其健康产生影响。

“养狗可促进养狗人士改善社交生活，社交本身会减少压力，而压力绝对是导致心血管疾病和心脏病的一大原因。”纽约市莱诺克斯希尔医院女性心脏健康中心副主任蕾切尔·邦德医生说道，她没有参与这项研究。

更多有待揭示

法尔认为，尽管他们的研究为养狗有益于健康提供了有力证据，但是他们的工作尚未完成，因为其研究并未解答为什么养狗有这样的功效，或者为什么养特定品种的狗似乎效果更明显。

邦德认为，养猎犬的人士可得到更多的锻炼，因为猎犬更好动，而小型犬活动量没这么大。

此外还要考虑其他因素，比如，养狗人士的性格，以及他们的整体健康状况和体力活动等。

邦德医生说：“很难说是否真的存在因果关系。尤其是这项研究，它并未普遍涉及心脏病患者，而且残疾人士养狗的可能性较小，所以，人们确实会问：是养狗带来心脏健康，还是养狗只是那些更可能拥有健康心脏人士的一个特征。”

尽管邦德可能不会建议患者养狗治病，但她说她并不反对他们养狗或者准备养狗，也不反对说说养狗的好处。

受益的不只是瑞典

尽管这项研究是在瑞典展开，但法尔教授坚信，研究成果或许也适用于包括美国在内的其他国家，因为各国常见犬种以及人们对养狗的态度是差不多的。

然而，法尔指出，各国气候差异、社会经济背景不同等因素，或对研究结果产生影响。

法尔表示：“瑞典气候偏冷，所以我们在室内养狗，主人遛狗要出门。在比较暖和的地区，人们可以在院子里养狗，就无需经常外出遛狗。”

邦德说：“我认为，美国人口更加多元化，很难将瑞典的数据运用到美国。应当在美国进行更多的相关研究。”

（译者单位：武汉轻工大学外国语学院）