Behavioral risk factors of mortality after spinal cord injury

Risk of Mortality and Life Expectancy After Spinal Cord Injury: The Role of Health Behaviors and Participation

PURPOSE: To identify the relationships between health behaviors and participation and life expectancy after spinal cord injury (SCI), while controlling for biographic and injury factors. METHODS: Data for this prospective cohort study were collected by mailed survey. Participants included 1,361 adults with traumatic SCI, 1 or more years post injury. Participants were enrolled an average of 9.7 years after injury, and mortality was determined at the end of 2007. There were 294 deaths by follow-up. Life expectancy was calculated utilizing person-years and logistic regression. RESULTS: When evaluating each factor while controlling for biographic and injury characteristics, it was found that smoking history, binge drinking, number of drinks consumed, and psychotropic prescription medication use were related to increased mortality risk, whereas exercise and weekly outings were associated with a lower mortality risk. In the final model, only smoking history, binge drinking, psychotropic prescription medication use, and weekly outings were predictive of mortality and life expectancy. CONCLUSION: Several behaviors identified may become targets of prevention strategies to promote longevity, including smoking cessation, stopping binge drinking, avoiding overreliance on psychotropic prescription medications, and promoting daily activities away from home.

Risk and protective factors for mortality after spinal cord injury

Our purpose was to systematically review research on postacute risk and protective factors for mortality after spinal cord injury including psychological, environmental, behavioral and health factors. A theoretical risk model was used to identify these sets of predictive factors and to structure this article. The majority of research identifies basic demographic (age and race) and injury factors (severity). More limited research has indicated that personality, purpose in life, income, social support and negative risk behaviors predict mortality. In terms of health factors and secondary conditions, pressure ulcers, amputations, depressive diagnosis and need for treatment also predict mortality. Interventions are needed that diminish the risk of secondary conditions and early mortality.

Life Expectancy Estimates in the Life Care Plan: Accounting for Economic Factors

OBJECTIVE

The purpose of this study was to summarize the existing scientific literature on the relationship between economic factors and life expectancy (LE) after spinal cord injury (SCI), present new data on the relationship between household income and LE, and present a revised theoretical risk model to account for the observed relationships.

RESEARCH DESIGN

Data were from a prospective cohort study of 1386 participants with SCI which began in 1997. Mortality status was determined 10 years later. Person year logistic regression was used to evaluate predictors of mortality and to generate LE estimates, as each year of follow-up was treated as a separate observation (rather than a single observation per person).

RESULTS

Results indicated significant relationships between age, injury severity, household income and LE, which suggest the need for more refined models of economic factors and LE.

CONCLUSIONS

LE estimates in life care plans need to account for economic factors in order to improve accuracy. It is important to allocate resources to meet all healthcare needs throughout the lifecycle to ensure that LE is not compromised.

Risk of mortality after spinal cord injury: an 8-year prospective study

Krause JS, Zhai Y, Saunders LL, Carter RE. Risk of mortality after spinal cord injury: an 8-year prospective study.

OBJECTIVE

To evaluate a theoretical model for mortality after spinal cord injury (SCI) by sequentially analyzing 4 sets of risk factors in relation to mortality (ie, adding 1 set of factors to the regression equation at a time).

DESIGN

Prospective cohort study of data collected in late 1997 and early 1998 with mortality status ascertained in December 2005. We evaluated the significance of 4 successive sets of predictors (biographic and injury, psychologic and environmental, behavioral, health and secondary conditions) using Cox proportional hazards modeling and built a full model based on the optimal predictors.

SETTING

A specialty hospital.

PARTICIPANTS

Adults (N=1386) with traumatic SCI, at least 1 year postinjury, participated. There were 224 deaths. After eliminating cases with missing data, there were 1209 participants, with 179 deceased at follow-up.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Mortality status was determined using the National Death Index and the Social Security Death Index.

RESULTS

The final model included 1 environmental variable (poverty), 2 behavioral factors (prescription medication use, binge drinking), and 4 health factors or secondary conditions (hospitalizations, fractures/amputations, surgeries for pressure ulcers, probable major depression).

CONCLUSIONS

The results supported the major premise of the theoretical model that risk factors are more important the more proximal they are in a theoretical chain of events leading to mortality. According to this model, mortality results from declining health, precipitated by high-risk behaviors. These findings may be used to target those who are at high risk for early mortality as well as to direct interventions to the particular risk factor.

Risk of hospitalizations after spinal cord injury: relationship with biographical, injury, educational, and behavioral factors

STUDY DESIGN

Cross-sectional survey.

OBJECTIVES

To assess the risk factors associated with hospitalization and the relationship of individual health behaviors with hospitalizations after spinal cord injury (SCI).

SETTING

A large specialty hospital in the southeastern USA.

METHODS

Persons with SCI responded (n=1386) to a mail survey assessing various aspects of their health, including health behaviors and number of hospitalizations in the past year. Logistic regression was used to assess the relationships between biographical, injury, educational, and health behavior factors with hospitalization in the past year.

RESULTS

Overall, 36.6% of participants were hospitalized on at least one occasion during the earlier year. Two biographical and injury characteristics were associated with hospitalization: race and SCI severity. Specifically, minorities and persons with non-ambulatory high cervical or non-cervical SCI were more likely to be hospitalized. Three behavioral factors were significantly associated with hospitalization after controlling for biographical and injury characteristics. Persons who used prescription medications, those who engaged more in smoking behaviors, and persons who reported more SCI-specific health behaviors were more likely to be hospitalized.

CONCLUSION

Specific health behaviors are associated with an increased hospitalization among persons with SCI. Future research is needed to assess the time sequence of these relationships.

Psychologic factors and risk of mortality after spinal cord injury

OBJECTIVE

To identify the association of 2 distinct psychologic constructs, personality and purpose in life (PIL), with risk of early mortality among persons with spinal cord injury (SCI).

DESIGN

Prospective cohort study with health data collected in late 1997 and early 1998 and mortality status ascertained in December 2005.

SETTING

A large rehabilitation hospital in the southeastern United States.

PARTICIPANTS

Adults (N=1386) with traumatic SCI, at least 1 year postinjury.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

We first evaluated the significance of a single psychologic predictor (a total of 6 scales) while controlling for biographic and injury predictors using Cox proportional hazards modeling and subsequently built a comprehensive model based on an optimal group of psychologic variables.

RESULTS

There were a total of 224 (16.2%) observed deaths in the full sample. The total number of deaths was reduced to 164 in the final statistical model (of 1128 participants) because of missing data. All 6 psychologic factors were statistically significant in the model that was adjusted for biographic and injury factors, whereas only 3 psychologic factors were retained in the final comprehensive model, including 2 personality scales (Impulsive Sensation Seeking, Neuroticism-Anxiety) and the PIL scale. The final comprehensive model only modestly improved the overall prediction of survival compared with the model with only biographic and injury variables, because the pseudo-R(2) increased from 0.121 to 0.129, and the concordance increased from 0.730 to 0.747.

CONCLUSIONS

The results affirm the importance of psychologic factors in relation to survival after SCI.