Being a healthcare assistant may put women at slightly higher risk of developing rheumatoid arthritis than the rest of the population, including registered nurses, a study has suggested.
Four particular occupations may put male and female workers at an elevated risk of developing rheumatoid arthritis, according to the Swedish study.
“Our findings… indicate that work-related factors, such as airborne harmful exposures, may contribute to disease development”
Among 28 different female employment roles, researchers found that assistant nurses were the only occupational group significantly associated with rheumatoid arthritis.
Meanwhile, for men, they found that workers in the manufacturing sector had a higher risk of developing rheumatoid arthritis than those in the professional, administrative, and technical sectors.
Within the manufacturing sector, male electrical and electronics workers and material handling operators had a two-fold increased risk of rheumatoid arthritis than the controls. Bricklayers and concrete workers had a three-fold increased risk.
The researchers analysed information on 3,522 patients with rheumatoid arthritis and 5,580 controls. They also gathered information on environmental, genetic, and immunological factors via blood samples and questionnaires between 1996 and 2014.
The 18-year study controlled for smoking habits, alcohol use, educational level, and body mass index, all of which are factors known to be associated with rheumatoid arthritis.
The researchers claimed their findings suggested that work-related factors, such as noxious airborne agents, may contribute to the pathogenesis of rheumatoid arthritis.
“It is important that findings on preventable risk factors are spread to employees, employers, and decision-makers”
Environmental factors are thought to play a role in the development of rheumatoid arthritis by triggering autoimmune reactions in susceptible individuals, noted the study authors.
For example, they said elevated levels of anti-citrullinated protein antibodies (ACPA), rheumatoid factor and anti-carbamylated protein antibodies had previously been found in patients before onset of the symptoms.
Among women, assistant nurses and attendants had a slightly increased risk of rheumatoid arthritis, said the researchers, from the Karolinska Institutet in Sweden.
“Assistant nurses and attendants was in this analysis the only occupational group significantly associated with ACPA-positive rheumatoid arthritis,” they said.
“Nurses, on the other hand, had no increased risk of ACPA-positive rheumatoid arthritis,” they stated in the journal Arthritis Care & Research.
They added: “No occupation among women was significantly associated with ACPA-negative rheumatoid arthritis.”
More research was needed to pinpoint the exposures that may be involved, said the study authors, who highlighted potential suspects as silica, asbestos, organic solvents, and motor exhaust.
They said they were already able to hypothesise a link between the three relevant male occupations and heightened exposure to silica and asbestos.
However, concerning the association they found between the long-term condition and nursing assistant roles, the authors admitted they “so far lack potential molecular explanations”.
Female HCAs at ‘slightly higher risk of rheumatoid arthritis’
“But a common trait in all four occupational groups associated with an increased risk of rheumatoid arthritis in our study is that they are physically demanding,” noted the researchers in the journal.
“Physical workload is a proposed risk factor for osteoarthritis, but for rheumatoid arthritis less research has been conducted,” they said.
“However, one previous study and one recent investigation… suggest that also some physical demanding tasks may be associated with an increased risk for rheumatoid arthritis,” they added.
Commenting on the study findings, lead author Anna Ilar said: “Our findings… indicate that work-related factors, such as airborne harmful exposures, may contribute to disease development.
“It is important that findings on preventable risk factors are spread to employees, employers, and decision-makers in order to prevent disease by reducing or eliminating known risk factors,” she said.