Good balance, muscle strength and an efficient gait contribute to people’s independence and well-being as they age. How these factors change, and at what rate, can help clinicians develop programs to ensure healthy aging. Individually, people can train their balance without special equipment and work on maintaining it over time.

In this study, 40 healthy, independent people over 50 underwent walking, balance, grip strength and knee strength tests. Half of the participants were under 65; the other half were 65 and older.

In the balance tests, participants stood on force plates in different situations: on both feet with eyes open, on both feet with eyes closed, on the non-dominant leg with eyes open, and on the dominant leg with eyes open. In the one-legged tests, participants could hold the leg they weren’t standing on where they wanted. The tests were 30 seconds each.

Standing on one leg — specifically the nondominant leg — showed the highest rate of decline with age.

“Balance is an important measure because, in addition to muscle strength, it requires input from vision, the vestibular system and the somatosensory systems,” says Kenton Kaufman, Ph.D., senior author of the study and director of the Motion Analysis Laboratory at Mayo Clinic. “Changes in balance are noteworthy. If you have poor balance, you’re at risk of falling, whether or not you’re moving. Falls are a severe health risk with serious consequences.”

Unintentional falls are the leading cause of injuries among adults who are 65 and older. Most falls among older adults result from a loss of balance.

In the other tests:

• Researchers used a custom-made device to measure participants’ grip. For the knee strength test, participants were in a seated position and instructed to extend their knee as forcefully as possible. Both the grip and knee strength tests were on the dominant side. Grip and knee strength showed significant declines by decade but not as much as balance. Grip strength decreased at a faster rate than knee strength, making it better at predicting aging than other strength measures.
• For the gait test, participants walked back and forth on an 8-meter, level walkway at their own pace and speed. Gait parameters didn’t change with age. This was not a surprising result since participants were walking at their normal pace, not their maximum pace, Dr. Kaufman says.
• There were no age-related declines in the strength tests that were specific to sex. This indicates that participants’ grip and knee strength declined at a similar rate. Researchers did not identify sex differences in the gait and balance tests, which suggests that male and female subjects were equally affected by age.

Dr. Kaufman says people can take steps to train their balance. For example, by standing on one leg, you can train yourself to coordinate your muscle and vestibular responses to maintain correct balance. If you can stand on one leg for 30 seconds, you are doing well, he says.

“If you don’t use it, you lose it. If you use it, you maintain it,” Dr. Kaufman says. “It’s easy to do. It doesn’t require special equipment, and you can do it every day.”

Funding for this study includes the Robert and Arlene Kogod Professorship in Geriatric Medicine and W. Hall Wendel Jr. Musculoskeletal Professorship.

The researchers compared various time windows of exposure, finding that the previous decade of water arsenic exposure up to the time of a cardiovascular disease event contributed the greatest risk. The findings are published in the journal Environmental Health Perspectives.

“Our findings shed light on critical time windows of arsenic exposure that contribute to heart disease and inform the ongoing arsenic risk assessment by the EPA. It further reinforces the importance of considering non-cancer outcomes, and specifically cardiovascular disease, which is the number one cause of death in the U.S. and globally,” said Danielle Medgyesi, a doctoral Fellow in the Department of Environmental Health Sciences at Columbia Mailman School. “This study offers resounding proof of the need for regulatory standards in protecting health and provides evidence in support of reducing the current limit to further eliminate significant risk.”

According to the American Heart Association and other leading health agencies, there is substantial evidence that arsenic exposure increases the risk of cardiovascular disease. This includes evidence of risk at high arsenic levels (>100µg/L) in drinking water. The U.S. Environmental Protection Agency reduced the maximum contaminant level (MCL) for arsenic in community water supplies (CWS) from 50µg/L to 10µg/L beginning in 2006. Even so, drinking water remains an important source of arsenic exposure among CWS users. The natural occurrence of arsenic in groundwater is commonly observed in regions of New England, the upper Midwest, and the West, including California.

To evaluate the relationship between long-term arsenic exposure from CWS and cardiovascular disease, the researchers used statewide healthcare administrative and mortality records collected for the California Teachers Study cohort from enrollment through follow-up (1995-2018), identifying fatal and nonfatal cases of ischemic heart disease and cardiovascular disease. Working closely with collaborators at the California Office of Environmental Health Hazard Assessment (OEHHA), the team gathered water arsenic data from CWS for three decades (1990-2020).

The analysis included 98,250 participants, 6,119 ischemic heart disease cases and 9,936 CVD cases. Excluded were those 85 years of age or older and those with a history of cardiovascular disease at enrollment. Similar to the proportion of California’s population that relies on CWS (over 90 percent), most participants resided in areas served by a CWS (92 percent). Leveraging the extensive years of arsenic data available, the team compared time windows of relatively short-term (3-years) to long-term (10-years to cumulative) average arsenic exposure. The study found decade-long arsenic exposure up to the time of a cardiovascular disease event was associated with the greatest risk, consistent with a study in Chile finding peak mortality of acute myocardial infarction around a decade after a period of very high arsenic exposure. This provides new insights into relevant exposure windows that are critical to the development of ischemic heart disease.

Nearly half (48 percent) of participants were exposed to an average arsenic concentration below California’s non-cancer public health goal <1 µg/L. In comparison to this low-exposure group, those exposed to 1 to <5 µg/L had modestly higher risk of ischemic heart disease, with increases of 5 to 6 percent. Risk jumped to 20 percent among those in the exposure ranges of 5 to <10 µg/L (or one-half to below the current regulatory limit), and more than doubled to 42 percent for those exposed to levels at and above the current EPA limit ≥10µg/L. The relationship was consistently stronger for ischemic heart disease compared to cardiovascular disease, and no evidence of risk for stroke was found, largely consistent with previous research and the conclusions of the current EPA risk assessment.

These results highlight the serious health consequences not only when community water systems do not meet the current EPA standard but also at levels below the current standard. The study found a substantial 20 percent risk at arsenic exposures ranging from 5 to <10 µg/L which affected about 3.2 percent of participants, suggesting that stronger regulations would provide significant benefits to the population. In line with prior research, the study also found higher arsenic concentrations, including concentrations above the current standard, disproportionally affect Hispanic and Latina populations and residents of lower socioeconomic status neighborhoods.

“Our results are novel and encourage a renewed discussion of current policy and regulatory standards,” said Columbia Mailman’s Tiffany Sanchez, senior author. “However, this also implies that much more research is needed to understand the risks associated with arsenic levels that CWS users currently experience. We believe that the data and methods developed in this study can be used to bolster and inform future studies and can be extended to evaluate other drinking water exposures and health outcomes.”

Co-authors are Komal Bangia, Office of Environmental Health Hazard Assessment, Oakland, California; James V. Lacey Jr and Emma S. Spielfogel,California Teacher Study, Beckman Research Institute, City of Hope, Duarte, California; and Jared A Fisher^, Jessica M. Madrigal, Rena R. Jones, and Mary H. Ward^, Division of Cancer Epidemiology and Genetics, National Cancer Institute.

The study was supported by the National Cancer Institute, grants U01-CA199277, P30-CA033572, P30-CA023100, UM1-CA164917, and R01-CA077398; and also funded by the Superfund Hazardous Substance Research and Training Program P42ES033719; NIH National Institute of Environmental Health Sciences P30 Center for Environmental Health and Justice P30ES9089, NIH Kirschstein National Research Service Award Institutional Research Training grant T32ES007322, NIH Predoctoral Individual Fellowship F31ES035306, and the Intramural Research Program of the NCI Z-CP010125-28.

“While exposure to persecution, war and displacement is associated with high rates of psychological disorders, such as PTSD and depression, remarkably the majority of refugees, despite having gone through very difficult experiences, don’t go on to develop a psychological disorder,” says Prof. Nickerson, Director of the Refugee Trauma and Recovery Program at UNSW’s School of Psychology.

Despite this, previous research has focused on trying to understand factors that predict psychopathology or psychological distress, rather than factors that predict wellbeing or resilience.

“More recently, however, there has been a movement towards a strengths-based approach in mental health, particularly in the refugee space, and we wanted to look at what research was out there,” says Prof. Nickerson.

The paper, out this week in Nature Mental Health, is the first to focus on factors contributing to better mental health in refugees.

To conduct the review, researchers searched four databases for relevant studies. They screened thousands of studies, 174 of which met the study criteria. 81% of the included papers were undertaken in refugees living in high-income countries (HICs) and 19% in lower-and-middle income countries (LMICs).

“The lack of research looking at predictors of good mental health highlighted the deficit focus of so much research into refugee mental health,” says Prof. Nickerson. She also noted that though 75% of the world’s refugees live in LMICs, most of the research took place in HICs.

“It underscores a real gap in refugee research,” says Prof. Nickerson.

What were the researchers looking for?

“Our systematic review covered studies investigating the mental health of refugees or asylum seekers, and we looked at factors that we called either protective or promotive of mental health. Protective factors are associated with reduced poor mental health outcomes, and promotive factors are associated with increased good mental health outcomes,” says Prof. Nickerson.

The researchers wanted to understand how to enhance the strengths of an individual or community to alleviate or even prevent distress.

“We were interested in everything from demographic and social factors to environmental and psychological factors,” Prof. Nickerson says.

“We wanted to be able to speak to a range of different implications and recommendations in the field of refugee mental health — from what psychologists or social workers might do with a client in a room, and also more broadly what kinds of conditions policy-makers should be creating in countries that host refuges to help people thrive and move forward after traumatic experiences.”

Study findings

The refugee experience is characterised by protracted exposure to danger and uncertainty. The review highlighted factors related to stability and predictability as having some of the strongest associations with good mental health in refugees.

“It makes a lot of sense that, if people who’ve been through very difficult experiences are going to overcome those and thrive, we need to create conditions where their basic needs for safety are met,” says Prof. Nickerson.

The study found a secure visa status, employment, income, good housing conditions and control over environmental circumstances were associated with good mental health outcomes in both HICs and/or LMICs.

Individuals vary in their capacity to cope with difficult circumstances, with resilience reflecting the extent to which an individual can recover or maintain good mental health in the context of adversity.

The review found that psychological factors such as cognitive strategies, self-efficacy and a sense of control were protective and promotive of wellbeing.

Building individual skills and capabilities to cope and thrive represents an important goal to promote good mental health in refugees.

“When we’re trying to understand how best to support people, we often look at the things that are going wrong, and that means our interventions are focused on those things. This study speaks to the importance of harnessing interventions that are associated with resilience, self-efficacy and psychological flexibility,” says Prof. Nickerson.

But experiences such as war, persecution and displacement occur at a societal level, and so approaches to promoting good mental health in their aftermath must extend beyond the individual.

“There is a consistent link between social engagement and support and good mental health outcomes among refugees, particularly for those in high-income countries,” Prof. Nickerson says.

“The ability to communicate in the host language, social support, and social engagement with both the refugees’ own community and the host community, along with religious coping strategies, were all linked with increased wellbeing.”

The way ahead

This review puts forward a clear research agenda, with at least three important pathways to progressing our understanding of refugee mental-health wellbeing, Prof. Nickerson says.

“One is to purposefully study factors associated with wellbeing and positive mental health outcomes, rather than just looking at factors that contribute to psychological distress. Refugee communities are remarkably resilient, and we have a lot to learn from people who have overcome adversity to thrive in their new country.

“Two is to fill the research gap in low-and-middle-income countries. The majority of refugees live in transit settings outside high-income countries. If we are going to provide effective supports, we need to understand factors that promote wellbeing in these contexts

“And finally it’s important to take a cross-disciplinary research approach. By bringing together researchers, psychologists, social workers and policy-makers, we can gain a more nuanced understanding of protective and promotive factors. Having refugee voices at the centre of this process is critical to help us understand priority areas for research and using these findings effectively. This will pave the way for developing policies and interventions that support refugee communities to thrive.”

This research was supported by funding from the Social Policy Group.