Couples often share diseases, even if they are not contagious

Memory researcher Fabricio Ballarini says that couples often rely on each other’s brains to store and recall memories. When a partner dies or leaves, a part of the other half’s memory seems to disappear as well. This unique connection between long-term partners not only impacts their memories and habits but also has physical effects. A recent study published in the American Heart Association’s journal analyzed data from over 30,000 couples worldwide and found that 20%-50% of them shared hypertension.

Among heterosexual couples aged 50 to 75, hypertension affected 37.9% in the United States, 47.1% in England, 20.8% in China, and 19.8% in India. In countries where hypertension is less common, the woman’s health was more affected. Compared to women married to men with normal blood pressure, American and English women living with a hypertensive man had a higher likelihood of having hypertension themselves (9% and 19%, respectively). Similarly, Chinese women had a 26% higher likelihood. The percentages were comparable for husbands in the countries studied.

The authors conclude that coordinated intervention for couples can effectively combat hypertension. These interventions include detection tests and implementing lifestyle changes like increased physical activity, stress reduction and dietary changes. Both individuals in a relationship should adopt these changes together to facilitate introduction and maintenance.

Couples often share more than just hypertension. A study conducted by Tohoku University (Japan) and Groningen University (Netherlands) revealed that many couples have similar blood pressure levels, cholesterol levels and even shared diseases like diabetes. The BMJ medical journal published another study that found that companions of individuals with certain non-communicable diseases had a higher risk of developing them. For conditions like asthma, depression and gastric ulcers, the risk increased by at least 70%.

Matching habits and genetics

Couples often share habits like exercising, and consuming alcohol and tobacco. They also tend to have similar body measurements. People typically choose partners who are similar in terms of education, economic status, social environment and even genetics. A 2013 study published in PNAS found that couples have greater genetic similarity compared to randomly chosen individuals, although this similarity is much smaller than factors like educational level. Although the exact mechanisms behind partner selection are not fully understood, it appears that we are attracted to those who resemble us. This could partly explain why couples who live together for a long time often share similar health conditions.

Over time, physical synchronization is accompanied by a psychological rhythm that reinforces its impact on the partner’s health. According to a study conducted by Shannon Mejía, a specialist in couples’ health at the University of Illinois, beliefs about aging are contagious and can affect the partner’s health. If you stop doing sports because you think you’re too old, that negative perception can become a self-fulfilling prophecy. Similarly, the belief that aging is inevitable and uncontrollable can hinder taking action. “Understanding the habits, rituals and beliefs of couples developed over years of living together can help gerontologists support successful aging,” said Mejía.

Making medical appointments as a couple

Gonzalo Grandes, head of the Primary Care Research Unit of Bizkaia (Spain), says, “The concept of family medicine stems from recognizing the similarities among couples and their children. Despite this, we still tend to rely on individualized medicine in practice, with separate clinical histories that fail to provide valuable information for treatment.” For Grandes, a comprehensive family perspective is valuable in addressing issues like childhood obesity. It involves focusing on nutrition and physical activity, which are responsibilities of the parents or other adults caring for the children. “In theory, it is widely accepted that structuring socio-health interventions at both the family and community levels is crucial for promoting health. However, implementing this approach can be challenging due to its complexity.”

According to Isabel Egocheaga of the Spanish Society of General and Family Physicians (SEMG), while hospitals don’t typically schedule appointments for couples, it’s a common practice in family medicine. “It’s more common in older couples, rather than younger ones,” she said. “Often, we conduct check-ups simultaneously, and some couples both take Sintrom [an anticoagulant] and do all the necessary follow-up tasks together.” Like the authors of the article published by the American Heart Association, Egocheaga believes couples can better control hypertension by doing activities together, like reducing salt intake and exercising.

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