Chronic conditions worsen outcomes for injured older workers, but not by much

Study finds workers with osteoarthritis, diabetes and heart disease take longer to recover from MSDs

Workers with certain chronic conditions may take longer to recover after a work-related musculoskeletal disorder (MSD). The influence of chronic conditions on disability after a work-related injury is the focus of two studies by Institute for Work & Health (IWH) Scientist Dr. Peter Smith.

With the growing number of older people staying at work, understanding the factors linked to their health is taking on a new importance. Older workers are not as prone to injuries as younger workers. But when injured, they tend to need more time to recover and more health-care services. As older workers are also more likely to have pre-existing chronic conditions, Smith wanted to find out if this higher prevalence leads to longer disability durations or more intensive use of health-care services.

He examined the extent to which preexisting chronic conditions account for age differences in time off work and healthcare expenditures following a work-related MSD. These studies were published in recent issues of the Scandinavian Journal of Work, Environment & Health (vol. 40, no. 2; doi:10.5271/sjweh.3397) and Medical Care (vol. 52, no. 1; doi:10.1097/ MLR.0000000000000017).

If older workers with particular chronic conditions are likely to be away from work longer, or have higher health-care expenditures, then tailored activities could be developed and targeted towards managing work disability in workers with these conditions, says Smith.

Women’s worst outcomes seen in middle age

Smith’s work draws on the use of three British Columbia population databases: claims records kept by the province’s workers’ compensation agency (WorkSafeBC), hospital discharge records, and all outpatient medical services provided to people who live in B.C. at least six months a year. The last two datasets allowed researchers to identify those workers’ compensation claimants who had pre-existing chronic conditions based on their health-care use. The study examined eight conditions, including diabetes, osteoarthritis, coronary heart disease, hypertension, hearing loss, depression, thyroid disorder and rheumatoid arthritis.

The first study looked at the link between older age and number of days workers were off work following an MSD injury. (It counted all days for which wage-replacement payouts were made over a two-year period.) Before accounting for chronic conditions, it found a straightforward link between age and time off for men. The older the male workers, the more days they were off. For women, the number of days peaked among the middle-aged (the 35-to-44 and the 45-54 age groups). Women over 55, in other words, took the same number of days off as women in the 25-to-34 age group.

Once chronic conditions were taken into account, certain conditions had a greater effect than others on recovery time. This holds true even after factoring in things like previous injuries, parts of body injured, occupational characteristics and so on. For both men and women, diabetes and depression were linked with more days off. Coronary heart disease was associated with more days off for women but not for men. Osteoarthritis was associated with more days off for men but not women.

The team used the same datasets to measure the amount of health-care dollars spent on older workers with an MSD injury—and the role of chronic conditions on that spending. Again, there was a corresponding rise in health spending for men as they aged, but a levelling off for women above 45. In general, average expenditures were higher for MSD claimants with pre-existing conditions. The only exception was for women with hearing conditions, who had slightly less health-care dollars spent on them than women without the condition.

A closer look at the links between chronic conditions, age and health-care spending reveals once again some similarities and some differences between men and women. For both groups, osteoarthritis and coronary heart disease were associated with higher health-care spending for older claimants. However, diabetes played a role in greater health-care spending for men but not women; depression played a role in increased spending for women but not men.

Other factors may be at play

These studies show that pre-existing chronic conditions such as osteoarthritis, diabetes and heart disease are important factors linking older age to greater disability after a work-related MSD injury. However, the impact of these conditions on age-related differences was relatively small, Smith notes.

This suggests that there is a lot more to age differences in the consequences of work injury than just pre-existing health factors, he says. So while there’s potential benefit to further understanding how some chronic conditions affect work injury outcomes, we might find greater potential savings by better understanding other factors to explain why older workers have worse labour-market and health-care outcomes.

We reported on a related study by Smith on the relationship between chronic conditions and being out of the labour force. For more on that study, go to: www.iwh.on.ca/at-work/74/heart-disease-arthritis-diabetes-raise-risk-of-....

Source: At Work, Issue 76, Spring 2014: Institute for Work & Health, Toronto

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