A Page From the Pandemic’s Silver Lining Playbook: Fewer Hip Fractures

One byproduct of the COVID-19 pandemic in the U.S. has been fewer hip fractures, according to Kaiser Permanente researchers.

The reason is unclear, but the researchers speculate that because more people are working at home or are unemployed, older people might be under closer supervision.

Kanu Okike, M.D., M.P.H., and his Kaiser Permanente colleagues, conducted their research by using data from the organization’s hip fracture registry. Hip fracture patients, ages 65 and older, at 31 Kaiser Permanente hospitals in California were included. The researchers divided the period from Jan. 1, 2020, to Sept. 26, 2021, into eight periods (presurge, the 2020 spring surge, summer 2020, and so on) and then calculated the hip fracture incidence as the number of hip fracture surgeries divided by the Kaiser’s health plan membership (more precisely, as the number procedures per 1 million person-weeks).

They compared the hip fracture incidence of each period during the pandemic to same period two years earlier. For example, they demarcated the “spring 2020 surge” as starting on March16, 2020, and ending on May 10, 2020. They compared the hip fracture incidence of that period — 96 per 1 million person-weeks — to the incidence in the period from March 16, 2018, to May 10, 2018, when it was 125 per 1 million person-weeks.

For seven of the eight periods, the hip fracture incidence was lower during the pandemic than in the comparison period two years earlier. The lone exception was the fall 2020 period (Aug. 24-Nov. 22) when it was the same (105 per 1 million person-weeks).

The hip fracture patients during the pandemic periods and the comparison periods were similar: average age, 82; 70% female; 74% white, and the vast majority (83%) with three more comorbidities.

The researchers floated decreased activity outside the home as another possible explanation for the pandemic dip in hip fractures although they noted that most older people break their hips following a “ground level” fall and most of those falls occur at home. Another factor might be the declining number of nursing home patients.

Okike and his colleagues that the hip fracture experience of Kaiser members might not be the same as the hip fracture for people elsewhere. They called for more research into the hip fracture incidence during other phases of the pandemic, partly because the results might yield insights into how to decrease hip fractures, which previous research has shown is associated with disability and mortality (12% to 37% in the year after the fracture).

The study results were published online in JAMA on Dec. 30, 2021.