Psychological predictors of mortality in old age

Depression and functional status as predictors of death among cancer patients

BACKGROUND

The current study examined the extent to which depression and functional limitations contribute to the mortality of newly diagnosed cancer patients. The analysis focused on differences in survival times among cancer patients with new experiences of depressive symptoms and functional limitations and patients with a history of such limitations.

METHODS

Data for the current analysis came from two panel studies conducted in Michigan between 1993 and 1997, including 871 adult (> or = 21 years of age) breast, colon, lung, and prostate carcinoma patients. Information came from four separate sources: the intake patient interview, a self-administered questionnaire, medical record audits, and the Death Certificate Registry of Michigan's Department of Community Health. With time to death as the primary outcome (followup of 571 days), data were analyzed using Kaplan-Meier product limit estimates and the Cox proportional hazard model.

RESULTS

Cancer patients who, after diagnosis, report only new depressive symptoms or functional limitations, have the same survival chances as those who report none. Cancer patients with either previous emotional problems or previous physical limitations face, within the first 19 months after diagnosis, a 2.6 times greater hazard of dying than patients without prior problems. Patients with both previous emotional problems and physical limitations before diagnosis have a 7.6 times greater hazard of dying within that time frame.

CONCLUSIONS

The current data show cancer patients with prior limitations and emotional problems have worse survival chances than would be expected on the basis of their cancer diagnosis alone. While depressive symptoms and functional limitations are common short-run responses to a cancer diagnosis and initial treatment, patients with no prior history of such problems appear to be more resilient.

Neuropsychologic correlates of brain white matter lesions depicted on MR images: 1921 Aberdeen Birth Cohort

PURPOSE

To examine relationships between brain white matter hyperintensities depicted at magnetic resonance (MR) imaging and performance on neuropsychologic tests in community-dwelling elderly adults.

MATERIALS AND METHODS

The 1921 Aberdeen Birth Cohort is a subsample of survivors of the Scottish Mental Survey of 1932 whose mental ability was tested at 11 years of age. Ninety-five of these subjects agreed to undergo brain MR imaging, an examination of general health, and a neuropsychologic evaluation. White matter hyperintensities detected at T2-weighted MR imaging were rated by using a semiquantitative method yielding two continuous variables: white matter lesions and periventricular lesions. Cognitive ability, including crystallized and fluid intelligence domains, was assessed with standard neuropsychologic tests.

RESULTS

Rating scores of white matter lesions were normally distributed (on a devised scale) with means of 1.14 for white matter lesions and 1.28 for periventricular lesions. Intra- and interobserver reliability coefficients for scores were high, generally above 0.7. There were significant correlations of medium effect size between the T2-weighted MR imaging-depicted white matter lesions and performance on tests of fluid-type intelligence. No significant correlation was demonstrated between white matter lesion ratings and tests of crystallized intelligence.

CONCLUSION

Lower fluid-type ("prevailing") intelligence test scores were associated with increased severity of white matter lesion ratings but not crystallized-type ("premorbid") intelligence test scores. This indicates that MR imaging-depicted white matter lesions are of clinical importance.

Cognitive functioning in centenarians: a coordinated analysis of results from three countries

Cognitive functions among centenarians in Japan, Sweden, and the United States are described. Three areas are explored. First, definitions and prevalence of dementia are compared between Japan and SWEDEN: Second, levels of cognitive performances between centenarians and younger age groups are presented. Third, interindividual variations in cognitive performances in centenarians and younger persons are compared in Sweden and the United STATES: The Swedish and Japanese studies show a variation in prevalence of dementia between 40% and 63% with a relatively higher prevalence among women. Part of the variance is probably due to differences in sampling and criteria of dementia. Along with the lower cognitive performance in centenarians, compared with younger age groups, the Swedish and U.S. results show a wider range of performance among centenarians for those semantic or experientially related abilities that tend to be maintained over the adult life span. In contrast, a smaller range of performance is found for centenarians on those fluid or process-related abilities that have shown a downward age-related trajectory of performance. Lower variability is probably due to centenarians reaching the lower performance limit. The conclusions agree with the assumption of a general increase in cognitive differentiation with increasing age, primarily in measures of crystallized intelligence. The conclusions point to the general robustness of results across countries, as well as to the relative importance of cognition for longevity.

Demographic, health, cognitive, and sensory variables as predictors of mortality in very old adults

Cognitive and sensorimotor predictors of mortality were examined in the Australian Longitudinal Study of Ageing, controlling for demographic and health variables. A stratified random sample of 1,947 males and females aged 70 and older were interviewed, and 1,500 were assessed on measures of health, memory. verbal ability, processing speed, vision, hearing, and grip strength in 1992 and 1994. Analyses of incident rate ratios for mortality over 4- and 6-year periods were conducted using Cox hierarchical regression analyses. Results showed that poor performance on nearly all cognitive variables was associated with mortality, but many of these effects were explained by measures of self-rated health and disease. Significant decline in hearing and cognitive performance also predicted mortality as did incomplete data at Wave 1. Results suggest that poor cognitive performance and cognitive decline in very old adults reflect both biological aging and disease processes.

Depressed mood and subjective health symptoms as predictors of mortality in patients with congestive heart failure: a two-years follow-up study

OBJECTIVE

The present study was undertaken in order to evaluate the relationship between depressed mood (depression, emotional distress) and disease-specific subjective health symptoms upon mortality risk among patients with congestive heart failure (CHF).

METHODS AND RESULTS

Proportional hazard models were used to evaluate the effects of selected biomedical, subjective health and psychological variables on mortality among 119 clinically stable patients (71.4% men; mean age 65.7 years +/- 9.6) with symptomatic heart failure, recruited from an outpatient cardiology practice. Twenty deaths were registered during the twenty-four-month period of data collection, all from cardiac causes. Results indicated that depressed mood was a significant predictor of mortality with a hazard ratio of 1.9, p .002. In contrast, subjective health was not a significant predictor of mortality in a Cox regression model that included depressed mood. The hazard ratio for a 1-point increase in Zung Depression Scale score was equal to 1.08 based on the multivariate model.

CONCLUSIONS

Results indicate that depressed mood is significantly related to increased mortality risk among heart failure patients. This finding is of concern to clinicians and should have implications for treatment of patients with congestive heart failure.