June 27, 2023 -- When she was in her 60s, Carole E., a retired accountant’s assistant in Albuquerque, NM, started having neck pain. She found out that three of her neck vertebrae were compressed and her whole spinal canal was narrow.
“The neck problem was addressed with surgery to stabilize the disks and prevent them from compressing further, which could have led to paralysis,” said Carole, now 81.
Although the surgery helped Carole’s neck, she continued to have problems with her back. She developed degenerative disk disease, and during the past 3 years, she has developed severe hip pain, muscle cramps, and seizing in her legs, as well as arthritis in one rotator cuff.
Carole also developed a heart condition.
“I always had a heart murmur, but it was very tiny and faint and I was told not to worry about it,” she said. “But about 3 years ago, it became a ‘moderate’ murmur and the cardiologist said we should watch it and evaluate it every 6 months.”
The murmur suddenly progressed to “severe” and surprised her cardiologist. Carole had successful valve replacement surgery a few months ago.
Now there is new evidence to suggest what happened to Carole and others like her. It suggests people like Carole, who are at high risk of heart disease, are significantly more likely to develop disorders of the muscles and joints (called musculoskeletal disorders).
Common, but Not Well Researched
Lead author of the study, Kurt Hegmann, MD, MPH, professor of family and preventive medicine at the University of Utah and director of the Rocky Mountain Center for Occupational and Environmental Health, explained what motivated the study.
“These injuries are common, affecting most people multiple times over a lifetime,” he said. Up to 5% of the U.S. population has carpal tunnel syndrome, as many as 41% experience tennis elbow (also called lateral epicondylitis), and up to one-third have tears in their rotator cuff.
These conditions are “painful, cause disability, can require surgery, and may cause chronic pain,” Hegmann said. “In short, they can impair people's daily life and enjoyment.”
But although they’re quite common, there is “little science” investigating their cause, he said. “We designed this study to comprehensively identify the risk factors driving these common problems so we could help prevent them.”
The researchers studied 9 years of data from 1,224 workers across various employment sectors (manufacturing, health care, office jobs, and food processing) in three states: Illinois, Utah, and Wisconsin.
At the beginning of the study, participants completed questionnaires about their age, sex, medical conditions (such as diabetes), tobacco use, hobbies, exercise habits, depression, and job satisfaction. They also had interviews about symptoms, such as tingling and numbness, and had physical exams and nerve conduction studies. Their body mass index (BMI) was calculated using their height and weight, and their blood pressure was measured.
The participants were followed on a monthly basis to track the development of symptoms of musculoskeletal disorders. The disorders studied included carpal tunnel syndrome, tennis elbow, golfer’s elbow, and rotator cuff tendinitis.
The researchers then compared the development of these disorders to cardiovascular disease risk, using a method derived from the Framingham Heart Study — a frequently used way to test a person’s 10-year risk for developing heart disease.
All of the analyses were adjusted to take into account factors that could affect the results, such as BMI or the physical strain from a participant’s work.
‘Early Warning Signal?’
The findings were striking. “The risks were up to 17-fold, which is as strong as the relationship between lung cancer and smoking; this relationship was so great, it was quite surprising to us,” Hegmann said.
Participants who were at 15% higher risk of heart disease had four times the risk of developing one or more musculoskeletal disorders, compared to people at low risk of heart disease; and their risk of developing four or more musculoskeletal disorders was 17 times greater.
“There is important corroborating evidence of impaired small blood vessels to injured tissues, due to cardiovascular risks, so the data overwhelmingly suggest that cardiovascular risks cause these injuries,” Hegmann said.
On the other hand, people who have musculoskeletal disorders “might also reduce their activity levels, which could feed into an increased risk for other cardiovascular problems, such as heart attacks.”
Carole says that over the last few years, she has become largely sedentary because of the physical pain from her hips and legs.
“I started cardiac rehab after my valve replacement, but using stationary bicycles is hurting my hips and legs and I’m in tremendous pain. And the machines that also exercise my arms are hurting my shoulders,” she said.
She has decided to consult a pain management specialist who can guide her in how to exercise safely and without pain.
Hegmann said that reducing cardiovascular disease risks “will reduce the risk of ever experiencing one of these common musculoskeletal injuries.”
Conversely, “the more of these injuries one develops, the ever-more critical it is to work to control that person's cardiovascular risks.”
In fact, the authors suggest, musculoskeletal disorders might be regarded as potential “early warning signals” for cardiovascular disease, since they may appear in someone without apparent heart issues years or even decades before heart symptoms may appear.