The role of intervening hospital admissions on trajectories of disability in the last year of life: prospective cohort study of older people

Abstract

Objective: To evaluate the role of intervening hospital admissions on trajectories of disability in the last year of life.

Design: Prospective cohort study.

Setting: Greater New Haven, Connecticut, United States, from March 1998 to June 2013.

Participants: 552 decedents from a cohort of 754 community living people, aged 70 years or older, who were initially non-disabled in four essential activities of daily living: bathing, dressing, walking, and transferring.

Main outcome measure: Occurrence of admissions to hospital and severity of disability (range 0-4), ascertained during monthly interviews for more than 15 years.

Results: In the last year of life, six distinct trajectories of disability were identified, from least disabled to most disabled: 95 participants (17.2%) had no disability, 61 (11.1%) had catastrophic disability, 53 (9.6%) had accelerated disability, 61 (11.1%) had progressively mild disability, 127 (23.0%) had progressively severe disability, and 155 (28.1%) had persistently severe disability. 392 (71.0%) participants had at least one hospital admission and 248 (44.9%) had multiple hospital admissions. For each trajectory the course of disability closely tracked the monthly prevalence of hospital admission. In a set of multivariable models that included several potential confounders, hospital admission in a given month had a strong independent effect on the severity of disability, in both relative and absolute terms. The largest absolute effect was observed for catastrophic disability, with a mean increase in disability score of 1.9 (95% confidence interval 1.5 to 2.4) in the setting of a hospital admission, corresponding to a rate ratio (or relative effect) of 2.0 (95% confidence interval 1.5 to 2.7).

Conclusions: In the last year of life, acute hospital admissions play an important role in the disabling process. Knowledge about the course of disability before these intervening events may facilitate clinical decision making at the end of life. For older patients admitted to hospital with progressive or persistent levels of severe disability, representing more than half of the decedents, clinicians might consider a palliative care approach to facilitate discussions about advance care planning and to better deal with personal care needs.

Fig 1 Trajectories of disability in last year of life among 552 decedents. Values for severity of disability represent the mean number of disabled activities of daily living (from 0 to 4). Black lines depict predicted trajectories, and companion lines depict observed trajectories. Ι bars represent 95% confidence intervals for predicted disability scores. Only 45 (8.2%) of the decedents had a probability of their assigned trajectory <0.70, with values ranging from 0.48 to 0.68; and in all cases, an adjacent trajectory had the next highest probability of membership, with values ranging from 0.16 to 0.42. Nearly 78% (n=35) of these trajectories were characterized by episodes of recovery from a more severe form of disability, while 20% (n=9) were characterized by disability in a single activity in the month before death without any preceding disability

Fig 2 Frequency distribution for number of hospital admissions in last year of life according to disability trajectory

Fig 3 Prevalence of hospital admission and severity of disability during each month in last year of life according to disability trajectory. Values for severity of disability represent the mean number of disabled activities of daily living (from 0 to 4)