Takahisa Ogawa1, Toshitaka Yoshii1, Masaya Higuchi2, Shingo Morishita1, Kiyohide Fushimi3, Takeo Fujiwara4, Atsushi Okawa1. 1. Department of Orthopedic Surgery, Tokyo Medical and Dental University, Tokyo, Japan. 2. Division of Palliative Care and Geriatric Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA. 3. Department of Health Policy and Informatics, Tokyo Medical and Dental University, Tokyo, Japan. 4. Department of Global Health Promotion, Tokyo Medical and Dental University, Tokyo, Japan.
Abstract
AIM: Among older patients undergoing hip fracture surgery, previous studies have shown a seasonal variation of in-hospital surgical complications. However, little is known about seasonal effects on mortality and systemic complications after hip fracture surgery. In the present study, we evaluated whether mortality and in-hospital systemic complications are influenced by seasonal differences. METHODS: We enrolled patients from a nationwide database who underwent hip fracture surgery between 2010 and 2018. The primary outcome was in-hospital mortality. The secondary outcomes were in-hospital systemic complications. The association between the seasonality and in-hospital outcomes was investigated using multivariable Cox, logistic regression and causal mediation analysis. RESULTS: With 425 856 patients (mean age 83.5 years; 79% women), overall in-hospital mortality was 5324 (1.2%). Fall and winter were associated with a higher mortality than spring (hazard ratio [HR] 1.16; P < 0.001; HR 1.14; P = 0.001, respectively). Across all the seasons, there were 36 834 overall systemic complications (8.6%), with respiratory infection being the most frequent (18 637 [4.4%]). Among these complications, only respiratory infection showed seasonal variation, with a higher prevalence in fall and winter. The mediated effect of respiratory infection on mortality was significantly higher in fall and winter compared with spring (fall, HR 1.06, proportion mediated 36.7%; winter, HR 1.14, proportion mediated 55.0%; all P < 0.001). CONCLUSIONS: We found a significantly higher mortality in fall and winter after hip fracture surgery. Specifically, in winter, the increased in-hospital death was largely attributed to the increased incidence of respiratory infection. Geriatr Gerontol Int 2021; 21: 398-403.
AIM: Among older patients undergoing hip fracture surgery, previous studies have shown a seasonal variation of in-hospital surgical complications. However, little is known about seasonal effects on mortality and systemic complications after hip fracture surgery. In the present study, we evaluated whether mortality and in-hospital systemic complications are influenced by seasonal differences. METHODS: We enrolled patients from a nationwide database who underwent hip fracture surgery between 2010 and 2018. The primary outcome was in-hospital mortality. The secondary outcomes were in-hospital systemic complications. The association between the seasonality and in-hospital outcomes was investigated using multivariable Cox, logistic regression and causal mediation analysis. RESULTS: With 425 856 patients (mean age 83.5 years; 79% women), overall in-hospital mortality was 5324 (1.2%). Fall and winter were associated with a higher mortality than spring (hazard ratio [HR] 1.16; P < 0.001; HR 1.14; P = 0.001, respectively). Across all the seasons, there were 36 834 overall systemic complications (8.6%), with respiratory infection being the most frequent (18 637 [4.4%]). Among these complications, only respiratory infection showed seasonal variation, with a higher prevalence in fall and winter. The mediated effect of respiratory infection on mortality was significantly higher in fall and winter compared with spring (fall, HR 1.06, proportion mediated 36.7%; winter, HR 1.14, proportion mediated 55.0%; all P < 0.001). CONCLUSIONS: We found a significantly higher mortality in fall and winter after hip fracture surgery. Specifically, in winter, the increased in-hospital death was largely attributed to the increased incidence of respiratory infection. Geriatr Gerontol Int 2021; 21: 398-403.