Functional Trajectories Before and After Major Surgery in Older Adults

Abstract

Objectives: We hypothesized that distinct sets of functional trajectories can be identified in the year before and after major surgery, with unique transition probabilities from pre to postsurgical functional trajectories, and that outcomes would be better among participants undergoing elective versus nonelective surgery.

Background: Major surgery is common and can be highly morbid in older persons. The relationship between the course of disability (ie, functional trajectory) before and after surgery in older adults has not been well-studied for most operations.

Methods: Prospective cohort study of 754 community-living persons 70 years or older. The analytic sample included 250 participants who underwent their first major surgery during the study period.

Results: Before surgery, 4 functional trajectories were identified: no disability (n = 60, 24.0%), and mild (n = 84, 33.6%), moderate (n = 73, 29.2%), and severe (n = 33, 13.2%) disability. After surgery, 4 functional trajectories were identified: rapid (n = 39, 15.6%), gradual (n = 76, 30.4%), partial (n = 70, 28.0%), and little (n = 57, 22.8%) improvement. Rapid improvement was seen for n = 31 (51.7%) participants with no disability before surgery, but was uncommon among those with mild disability (n = 8, 9.5%) and was not observed in the moderate and severe trajectory groups. For participants with mild to moderate disability before surgery, gradual improvement (n = 46, 54.8%) and partial improvement (n = 36, 49.3%) were most common. Most participants with severe disability (n = 27, 81.8%) before surgery exhibited little improvement. Outcomes were better for participants undergoing elective versus nonelective surgery.

Conclusions: Functional prognosis in the year after major surgery is highly dependent on premorbid function.

FIGURE 1.

Functional trajectories in the year before and after major surgery (N = 250). The number and percentage of participants for each trajectory are shown within parentheses. The 8 (3.2%) participants who died after surgery, but before their first monthly interview, could not be assigned to a postsurgery trajectory. The percentages may not sum to 100 because of rounding. The number of disabilities ranged from 0 to 13, based on 4 basic activities, 5 instrumental activities, and 4 mobility activities. The solid lines indicate the model trajectories, whereas the open circles show the corresponding observed values at each time point. The dashed lines indicate 95% confidence intervals for the predicted severity of disability. The average posterior probabilities of class membership for the trajectories before and after surgery were all greater than 0.9, with values ranging from 0.94 for no disability to 0.98 for moderate disability, and from 0.96 for gradual improvement to 0.98 for rapid improvement.

FIGURE 2.

Adjusted probabilities of postsurgery functional trajectories conditional on presurgery functional trajectories stratified by elective versus nonelective surgery. Covariates included age, sex, race, less than high school education, number of chronic conditions, cognitive impairment, depressive symptoms, physical frailty, and type of surgery (abdominal, musculoskeletal, or other). To account for possible temporal changes in surgical and hospital care during the study period, the year of surgery was also included as a covariate. The probabilities may not sum to 1.0 because of rounding.