UWL: Association With Outcomes (2009)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To better understand the effect of bereavement on family caregivers by examining pre-death vs. post-death changes in self-reported and objective health outcomes among elderly persons providing varying levels of care prior to their spouse's death.

Inclusion Criteria:
  • Men and women aged 65 years or older were recruited from four United States communities
  • Individuals whose spouse died during an average four-year follow-up.
Exclusion Criteria:
  • Being wheelchair bound in the home
  • Unable to participate in the examination at the field centers
  • Undergoing active treatment for cancer.
Description of Study Protocol:

Recruitment

Participants were from the Caregiver Health Effects Study, an ancillary study of the Cardiovascular Health Study, a large population-based study of elderly persons with a large sample size (approximately 400 spousal caregivers and 400 matched controls). Beginning in 1989, a total of 5,201 men and women aged 65 years or older were recruited from four US communities. Potential participants were identified from a random sample stratified by age group from the Health Care Financing Administration Medicare Enrollment lists. A supplemental cohort of 687 African American men and women aged 65 years or older was recruited prior to the fourth wave of CHS data collection using the same sampling methods.

Design

Prospective, population-based cohort study. 

Statistical Analysis

  • All spousal deaths that occurred after baseline and before wave four were included
  • Repeated measures ANCOVA was used.
Data Collection Summary:

Timing of Measurements

Study conducted between 1993 and 1998.

Dependent Variables

  • Depressive symptoms assessed by 10-item Center for Epidemiological Studies-Depression scale
  • Antidepressant medication use
  • Six health risk behaviors: Missing at least one physician appointment in the last six months, not having enough time to go to the physician, not having enough time to exercise, forgetting to take medication, not getting enough rest in general and not being able to slow down and get enough rest when sick
  • Weight measured with standardized balance beam scale.

Independent Variables

  • Non-caregivers: Spouse had no difficulties with ADL or IADL tasks
  • Caregivers who reported no strain: No strain, minimal spouse difficulties 
  • Strained caregivers: Spouse had difficulties and they reported some physical or emotional strain with helping. 

Control Variables

  • Age
  • Sex
  • Race
  • Education
  • Prevalent cardiovascular disease at baseline
  • Interval between pre-death and post-death assessments.
Description of Actual Data Sample:
  • Initial N: 129 individuals
  • Attrition (final N): 129 individuals; 40 non-caregivers, 37 caregivers who reported no strain and 52 strained caregivers
  • Age: 66 to 96 years of age
  • Location: Four US communities (Forsyth County, NC;, Washington County, MD; Sacramento County, CA, Allegheny County, PA).
Summary of Results:

Characteristics of the Sample and Levels of Depression Symptoms, Health Risk Behaviors and Weight Before and After Death of Spouse, by Caregiving Status

Variables

Total Sample (N=129)

Non-caregiver (N=40)

Caregiver / No Strain (N=37)

Caregiver / Strain (N=52)

Age, years

80.1±4.9 79.4±4.1

80.9±5.3 

80.0±5.2

White, percentage

89.9

90.0

91.9

88.5
Female, percentage 74.4 77.5 56.8 84.6
High school graduate or less, percentage 55.0 52.5 54.0 57.7
Prevalent cardiovascular diseases, number 0.33±0.67 0.40±0.71 0.14±0.42 0.42±0.75
Depression symptoms, pre-bereavement, number 6.82±5.68 4.76±3.87 5.31±5.44 9.48±6.04
Depression symptoms, post-bereavement, number 8.43±6.01 8.31±6.64 7.25±5.38 9.35±5.87
Health risk behaviors, pre-bereavement, number 0.81±1.32 0.31±0.80 0.32±0.63 1.54±1.64
Health risk behaviors, post-bereavement, number 0.43 ± 0.92 0.25±0.59 0.27 ± 0.77 0.67 ± 1.15
Weight, pre-bereavement, lbs 153.9 ± 30.8 147.0±27.8 160.9±35.0 154.0±29.0
Weight, post-bereavement, lbs 152.0 ± 31.3 143.3±27.1 160.7±37.2 151.8±28.1

Other Findings

  • Controlling for age, sex, race, education, prevalent cardiovascular disease at baseline, and interval between pre-death and post-death assessments, CES-D scores remained high but did not change among strained caregivers (9.44 vs. 9.19, P=0.76), while these scores increased for both non-caregivers (4.74 vs. 8.25, P<0.001) and non-strained caregivers (4.94 vs. 7.13, P=0.04)
  • Non-caregivers were significantly more likely to be using nontricyclic antidepressant medications following the death than the non-strained caregiver group (odds ratio, 12.85; 95% confidence interval, 1.02 to 162.13; P=0.05)
  • The strained caregiver group experienced significant improvement in health risk behaviors following the death of their spouse (1.47 vs. 0.66 behaviors, P<0.001) while the non-caregiver and non-strained caregiver groups showed little change [0.27 vs. 0.27 (P=0.99), and 0.46 vs. 0.27 (P=0.39) behaviors, respectively]
  • Non-caregivers experienced significant weight loss following the death [149.1 vs. 145.3 lb (67.1 vs. 65.4kg), P=0.005], while the strained and non-strained caregiving groups did not show significant weight change [156.2 vs. 155.2 lb (70.3 vs. 69.8kg), P=0.41 and 156.2 vs. 154.0 lb (70.3 vs. 69.3kg), P=0.12, respectively].  
Author Conclusion:

These data indicate that the impact of losing one's spouse among older persons varies as a function of the caregiving experiences that precede the death. Among individuals who are already strained prior to the death of their spouse, the death itself does not increase their level of distress. Instead, they show reductions in health risk behaviors. Among non-caregivers, losing one's spouse results in increased depression and weight loss.

Funding Source:
Government: NIMH, National Institute on Aging, NHLBI
Reviewer Comments:

Small numbers of subjects in groups, but national representation.

Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) N/A
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) N/A
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? N/A
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? Yes
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? Yes
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? N/A
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? Yes
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes