Childless older women have a higher risk of sustaining a hip fracture than mothers. Several biological mechanisms linking parity to bone health among women have been proposed but it remains unclear whether a similar association exists among men. Adult children may also support their ageing parents with hip fracture, thereby potentially increasing survival chances.
To investigate how having children is related to the incidence of and survival after hip fracture among Swedish men and women over the age of 70.
This nation-wide cohort study is based on data from several administrative population registers and a clinical hip fracture register. During 2013 to 2017, we estimated multivariable-adjusted incidence rate ratios to examine the association between number of children and incidence of first hip fracture and hazard ratios to examine survival after first hip fracture.
More than two million individuals were followed for hip fracture incidence and 45,991 patients for survival. Women had a higher risk of sustaining a hip fracture, but men had substantially higher mortality than women. Adjusting for education, comorbidity level, and further covariates, having children was associated with a lower risk of sustaining a hip fracture and a longer survival after hip fracture.
Older childless individuals may constitute risk groups for both the incidence of and mortality after hip fracture. Mechanisms linking parity to hip fracture risk are likely complex and not limited to biological mechanisms related to pregnancy, childbirth, or breastfeeding among women.