Cognitive reserve and mortality in dementia: the role of cognition, functional ability and depression

OBJECTIVE

This study examined whether dementia patients with greater cognitive reserve had increased mortality rates, and whether this association was different across strata of cognition, functional ability and depression.

METHODS

In the community-based Amsterdam Study of the Elderly, 261 non-institutionalized dementia patients, identified using the Geriatric Mental State Schedule (GMS), were followed for an average of 55.5 months after which mortality data were obtained. Cognitive reserve was indicated by years of education and pre-morbid intelligence (measured using the Dutch Adult Reading Test). Cognition, functional ability and depression were indicated by Mini-Mental State scores, ADL and IADL measurements and GMS depressive syndrome, respectively.

RESULTS

During the follow-up 146 persons (55.9%) died. Cox regression analyses showed that more highly educated dementia patients had higher mortality rates, only if they had low MMSE scores or if they had a concurrent depression. Pre-morbid intelligence was associated with a higher mortality rate, independent of cognition, but this association was much stronger among patients with depression. The positive association between education or intelligence and mortality was not modified by functional disabilities.

CONCLUSIONS

The results suggest that dementia patients with greater cognitive reserve have increased mortality rates, only if the disease has progressed to such an extent that clinical symptoms are more severe. In this respect, the reserve hypothesis needs a modification. Depression in dementia patients with greater cognitive reserve may reflect a subgroup of patients with poor prognosis.

New and worsening conditions and change in physical and cognitive performance during weekly evaluations over 6 months: the Women's Health and Aging Study

BACKGROUND

Despite the large burden of chronic disease in older persons, especially those with disability, little research has documented changes in symptomatology over short periods of time. Additionally, although it has been demonstrated that medical conditions strongly affect functional level, short-term worsening in condition status has not been investigated for its impact on functional change.

METHODS

In a substudy of the Women's Health and Aging Study, 102 women with mild to severe disability received weekly home visits over a 6-month period. Each week they were queried as to the onset of 14 acute, generally self-limited conditions and the worsening or new diagnosis of 12 chronic conditions (condition reporting). They also received a battery of physical and cognitive performance tests.

RESULTS

There was a high rate of condition reporting over 24 weekly interviews. Nearly all women reported acute and episodic conditions; the average number of weeks of reporting one or more conditions was 11.8 per woman. For chronic conditions, the average number of weeks of reporting worsening of one or more conditions was 5.2 per woman. Multiple reports of onset or worsening of specific conditions were common, especially for arthritis of the hands, hips, knees, or feet; urinary problems; dizziness or unsteadiness on feet; and back pain. The total number of condition reports and number of weeks of condition reporting were generally not associated with an individual's slope of change in performance tests. For specific conditions, there were generally small and nonsignificant changes in performance in those who reported onset or worsening after 3 or more weeks of not reporting this.

CONCLUSIONS

Older disabled women frequently report the onset or worsening of acute and chronic conditions. In weekly observations, these conditions are not related to changes in physical and cognitive performance measures. Possible reasons for this are that (a) condition reporting may not be valid, (b) changes or severity of conditions were of insufficient magnitude to affect functioning, or (c) performance measures are not sensitive to the kinds of changes in chronic and acute conditions that affect people from week to week. We concluded that performance measures are not useful in monitoring modest, short-term changes in health status, but may still be valuable for assessing more major changes in health and functioning over time.

Psychological distress in victims of elder mistreatment: the effects of social support and coping

The objective of the study was to examine psychological distress in victims of elder mistreatment and to determine whether social support, coping style, mastery, and perceived self-efficacy favorably influence the psychological health of these victims. The study sample consisted of 77 subjects who reported recent chronic verbal aggression, physical aggression, or financial mistreatment, and a control group of 147 subjects who had not been mistreated. All participants were elderly persons who were over 65 years of age and living independently in the community. Social support, coping style, mastery, and perceived self-efficacy were measured by means of a standardized home interview. Psychological distress was measured by means of the General Health Questionnaire (GHQ-12). Victims of elder mistreatment had significantly higher levels of psychological distress than nonvictims. Social support showed a favorable effect on the level of psychological distress in victims, but not in nonvictims; victims who received more social support showed less psychological distress. A lower sense of mastery, a negative perception of self-efficacy, and a passive reaction pattern were associated with higher levels of psychological distress in victims as well as in nonvictims. The beneficial role of social support, locus of control, and perceived self-efficacy on the level of psychological distress could be of importance in the development of future intervention programs.

Lower body osteoarticular pain and dose of analgesic medications in older disabled women: the Women's Health and Aging Study

OBJECTIVES

This study assessed use and dosage of analgesic medications in relation to severity of osteoarticular pain.

METHODS

The type and dose of analgesic medication and the severity of pain in the lower back, hips, knees, or feet of 1002 older disabled women were assessed.

RESULTS

Severe pain and the use of analgesic medications were reported by 48.5% and 78.8% of women, respectively. Among those who had severe pain, 41.2% were using less than 20% of the maximum analgesic dose. Overall, 6.6% of women were using more than 100% of the maximum dose.

CONCLUSIONS

Severe pain is common. Additional, more effective, and safe analgesic treatments are needed for controlling pain in older persons.

Social network, social support, and loneliness in older persons with different chronic diseases

OBJECTIVES

This study examines whether patterns of social network size, functional social support, and loneliness are different for older persons with different types of chronic diseases.

METHODS

In a community-based sample of 2,788 men and women age 55 to 85 years participating in the Longitudinal Aging Study Amsterdam, chronic diseases status, social network size, support exchanges, and loneliness were assessed.

RESULTS

Social network size and emotional support exchanges were not associated with disease status. The only differences between healthy and chronically ill people were found for receipt of instrumental support and loneliness. Disease characteristics played a differential role: greater feelings of loneliness were mainly found for persons with lung disease or arthritis, and receiving more instrumental support was mainly found for persons with arthritis or stroke.

DISCUSSION

The specifics of a disease appear to play a (small) role in the receipt of instrumental support and feelings of loneliness of chronically ill older persons.

Effects of social support and personal coping resources on depressive symptoms: different for various chronic diseases?

Effects of psychosocial coping resources on depressive symptoms were examined and compared in older persons with no chronic disease or with recently symptomatic diabetes mellitus, lung disease, cardiac disease, arthritis, or cancer. The 719 persons without diseases reported less depressive symptoms than the chronically ill. Direct favorable effects on depressive symptoms were found for having a partner, having many close relationships, greater feelings of mastery, greater self-efficacy expectations, and high self-esteem. Buffer effects were observed for feelings of mastery, having many diffuse relationships, and receiving emotional support. Buffer effects were differential across diseases for emotional support (in cardiac disease and arthritis only) and for diffuse relationships (in lung disease). Receiving instrumental support was associated with more depressive symptoms, especially in diabetes patients.

Chronically depressed mood and cancer risk in older persons

BACKGROUND

Depression has been proposed as a predisposing factor for cancer, but prospective studies have been inconclusive. We examined whether a high level of depressive symptoms, present for a long time, is associated with increased risk of cancer in the elderly.

METHODS

Data were obtained and analyzed from persons who lived in three communities (Massachusetts, Iowa, and Connecticut) of the Established Populations for Epidemiologic Studies of the Elderly, a prospective cohort study with a mean follow-up of 3.8 years that included 4825 persons (1708 men and 3117 women) aged 71 years and older. Chronically depressed mood was defined as present when the number of depressive symptoms exceeded specific cut points on the Center for Epidemiologic Studies-Depression scale at baseline (1988) and 3 and 6 years before baseline. New cases of cancer were identified from Medicare hospitalization records and death certificates.

RESULTS

Of the 4825 persons studied, 146 (3.0%) were chronically depressed. The incidence rate of cancer was 30.5 per 1000 person-years for the 146 persons with chronic depression and 21.9 per 1000 person-years for the 4679 nonchronically depressed persons. After adjustment for age, sex, race, disability, hospital admissions, alcohol intake, and smoking, the hazard ratio for cancer associated with chronically depressed mood was 1.88 (95% confidence interval = 1.13-3.14). The excess risk of cancer associated with chronic depression was consistent for most types of cancer and was not specific to cigarette smokers.

CONCLUSION

When present for at least 6 years, depression was associated with a generally increased risk of cancer.

Effects of social support and personal coping resources on depressive symptoms: different for various chronic diseases?

Effects of psychosocial coping resources on depressive symptoms were examined and compared in older persons with no chronic disease or with recently symptomatic diabetes mellitus, lung disease, cardiac disease, arthritis, or cancer. The 719 persons without diseases reported less depressive symptoms than the chronically ill. Direct favorable effects on depressive symptoms were found for having a partner, having many close relationships, greater feelings of mastery, greater self-efficacy expectations, and high self-esteem. Buffer effects were observed for feelings of mastery, having many diffuse relationships, and receiving emotional support. Buffer effects were differential across diseases for emotional support (in cardiac disease and arthritis only) and for diffuse relationships (in lung disease). Receiving instrumental support was associated with more depressive symptoms, especially in diabetes patients.

Depression in survivor of stroke: a community-based study of prevalence, risk factors and consequences

Depression in survivors of stroke is both common and clinically relevant. It is associated with excess suffering, handicap, suicidal ideation and mortality and it hampers rehabilitation. Most of the data currently available are derived from clinical studies. The objective of the present study was to study the prevalence, risk factors and consequences of depression in survivors of stroke, in a large (n = 3050) community-based study of older (55-85 years) people in three regions of the Netherlands. Depression was measured using the CES-D scale; histories of stroke were obtained using self-reports and data from general practitioners. The study was designed as a case-control study, using both bivariate and multivariate analyses. The prevalence of depression in stroke survivors was 27%, which was significantly higher than the base rate (OR 2.28, 95% CI 1.61-3.24). Both stroke-related disease characteristics and psychosocial characteristics of the respondents were predictors of depression. The consequences of depression were most evident in the realm of disability and impairment of well-being. The patterns of service utilization showed that depressed survivors of stroke are relatively high users of a wide range of health services.

Emotional vitality among disabled older women: the Women's Health and Aging Study

OBJECTIVE

To examine correlates of high overall level of emotional functioning (emotional vitality) in disabled older women.

DESIGN

A community-based study: The Women's Health and Aging Study.

POPULATION

A total of 1002 moderately to severely disabled women aged 65 and older living in the community.

MEASUREMENTS

Emotional vitality was defined as having a high sense of personal mastery, being happy, and having low depressive symptomatology and anxiety. Correlations with demographics, health status, and social context were examined.

RESULTS

Despite their physical disabilities, 35% of the 1002 disabled older women were emotionally vital. The percent of emotionally vital women declined with increasing severity of disability. After adjustment for disability status, a significantly increased likelihood for being emotionally vital was found for black race (OR=1.69) and for having higher income (OR=1.77), better cognition (OR=2.36), no vision problems (OR=1.61), adequate emotional support (OR=2.54), and many face-to-face contacts (OR=1.64). Having more than one negative life event reduced the likelihood of emotional vitality (OR=0.57).

CONCLUSION

A substantial proportion of even the most disabled older women can be described as emotionally vital. Findings also suggest that emotional vitality is not solely a function of stable, enduring individual characteristics but that health status, disability, and sociodemographic context also have an influence on emotional vitality.

Depressive symptoms and physical decline in community-dwelling older persons

CONTEXT

Significant symptoms of depression are common in the older community-dwelling population. Although depressive symptoms and disability may commonly occur in the same person, whether depressive symptoms contribute to subsequent functional decline has not been elucidated.

OBJECTIVE

To determine whether depressive symptoms in older persons increase the risk of subsequent decline in physical function as measured by objective performance-based tests.

DESIGN

A 4-year prospective cohort study.

SETTING

The communities of Iowa and Washington counties, Iowa.

PARTICIPANTS

A total of 1286 persons aged 71 years and older who completed a short battery of physical performance tests in 1988 and again 4 years later.

MAIN OUTCOME MEASURES

Baseline depressive symptoms were assessed by the Center for Epidemiological Studies Depression Scale. Physical performance tests included an assessment of standing balance, a timed 2.4-m (8-ft) walk, and a timed test of 5 repetitions of rising from a chair and sitting down.

RESULTS

After adjustment for baseline performance score, health status, and sociodemographic factors, increasing levels of depressive symptoms were predictive of greater decline in physical performance over 4 years (odds ratio for decline in those with depressed mood vs those without, 1.55; 95% confidence interval [CI], 1.02-2.34). Even among those at the high end of the functional spectrum, who reported no disability, the severity of depressive symptoms predicted subsequent decline in physical performance (odds ratio for decline, 1.03; 95% CI, 1.00-1.08).

CONCLUSIONS

This study provides evidence that older persons who report depressive symptoms are at higher risk of subsequent physical decline. These results suggest that prevention or reduction of depressed mood could play a role in reducing functional decline in older persons.

Cardiovascular events and mortality in newly and chronically depressed persons > 70 years of age

The role of duration of depressed mood in the prediction of cardiovascular disease (CVD) requires further study, as it has been suggested that emerging depressive symptoms may be a better predictor than persistent depressive symptoms. This prospective cohort study of 3,701 men and women aged > 70 years uses 3 measurement occasions of depressive symptomatology (Center for Epidemiologic Studies-Depression Scale) during a 6-year period to distinguish persons who were newly (depressed at baseline but not at 3 and 6 years before baseline) and chronically depressed (depressed at baseline and at 3 or 6 years before baseline). Their risk of subsequent CVD events and all-cause mortality was compared with that of subjects who were never depressed during the 6-year period. Outcome events were based on death certificates and Medicare hospitalization records. During a median follow-up of 4.0 years, there were 732 deaths (46.2/1,000 person-years) and 933 new CVD events (64.7/1,000 person-years). In men, but not in women, newly depressed mood was associated with an increased risk of CVD mortality (relative risk 1.75, 95% confidence interval [CI] 1.00 to 3.05), new CVD events (relative risk 2.07, 95% CI 1.44 to 2.96), and new coronary heart disease events (relative risk 2.03, 95% CI 1.28 to 3.24) after adjustment for traditional CVD risk factors. The association between newly depressed mood and all-cause mortality was smaller (relative risk 1.40, 95% CI 0.95 to 2.07). Chronic depressed mood was not associated with new CVD events or all-cause mortality. Our findings suggest that newly depressed older men, but not women, were approximately twice as likely to have a CVD event than those who were never depressed. In men, recent onset of depressed mood is a better predictor of CVD than long-term depressed mood.

Depression and physical health in later life: results from the Longitudinal Aging Study Amsterdam (LASA)

BACKGROUND

In later life, declining physical health is often thought to be one of the most important risk factors for depression. Major depressive disorders are relatively rare, while depressive syndromes which do not fulfill diagnostic criteria (minor depression) are common.

METHODS

Community-based sample of older adults (55-85) in the Netherlands: baseline sample n = 3056; study sample in two stage screening procedure n = 646. Both relative (odds ratios) and absolute (population attributable risks) measures of associations reported.

RESULTS

In multivariate analyses minor depression was related to physical health, while major depression was not. General aspects of physical health had stronger associations with depression than specific disease categories. Significant interactions between ill health and social support were found only for minor depression. Major depression was associated with variables reflecting long-standing vulnerability.

CONCLUSION

Major and minor depression differ in their association with physical health.

LIMITATION

Cross-sectional study relying largely on self-reported data.

CLINICAL RELEVANCE

In major depression, with or without somatic co-morbidity, primary treatment of the affective disorder should not be delayed. In minor depression associated with declining physical health, intervention may be aimed at either or both conditions.

Do disease specific characteristics add to the explanation of mobility limitations in patients with different chronic diseases? A study in The Netherlands

STUDY OBJECTIVES

To determine whether disease specific characteristics, reflecting clinical disease severity, add to the explanation of mobility limitations in patients with specific chronic diseases.

DESIGN AND SETTING

Cross sectional study of survey data from community dwelling elderly people, aged 55-85 years, in the Netherlands.

PARTICIPANTS AND METHODS

The additional explanation of mobility limitations by disease specific characteristics was examined by logistic regression analyses on data from 2830 community dwelling elderly people.

MAIN RESULTS

In the total sample, chronic non-specific lung disease, cardiac disease, peripheral atherosclerosis, diabetes mellitus, stroke, arthritis and cancer (the index diseases), were all independently associated with mobility limitations. Adjusted for age, sex, comorbidity, and medical treatment disease specific characteristics that explain the association between disease and mobility mostly reflect decreased endurance capacity (shortness of breath and disturbed night rest in chronic non-specific lung disease, angina pectoris and congestive heart failure in cardiac disease), or are directly related to mobility function (stiffness and lower body complaints in arthritis). For atherosclerosis and diabetes mellitus, disease specific characteristics did not add to the explanation of mobility limitations.

CONCLUSIONS

The results provide evidence that, to obtain more detailed information about the differential impact of chronic diseases on mobility, disease specific characteristics are important to take into account.

Effects of social support and personal coping resources on mortality in older age: the Longitudinal Aging Study Amsterdam

This study focuses on the role of social support and personal coping resources in relation to mortality among older persons in the Netherlands. Data are from a sample of 2,829 noninstitutionalized people aged between 55 and 85 years who took part in the Longitudinal Aging Study Amsterdam in 1992-1995. Social support was operationally defined by structural, functional, and perceived aspects, and personal coping resources included measures of mastery, self-efficacy, and self-esteem. Mortality data were obtained during a follow-up of 29 months, on average. Cox proportional hazards regression models revealed that having fewer feelings of loneliness and greater feelings of mastery are directly associated with a reduced mortality risk when age, sex, chronic diseases, use of alcohol, smoking, self-rated health, and functional limitations are controlled for. In addition, persons who received a moderate level of emotional support (odds ratio (OR) = 0.49, 95% confidence interval (CI) 0.33-0.72) and those who received a high level of support (OR = 0.68, 95% CI 0.47-0.98) had reduced mortality risks when compared with persons who received a low level of emotional support. Receipt of a high level of instrumental support was related to a higher risk of death (OR = 1.74, 95% CI 1.12-2.69). Interaction between disease status and social support or personal coping resources on mortality could not be demonstrated.

Chronic medical conditions and mental health in older people: disability and psychosocial resources mediate specific mental health effects

BACKGROUND

This study describes the differences in psychological distress, disability and psychosocial resources between types of major medical conditions and sensory impairments (collectively denoted as CMCs); and tests whether disability and psychosocial resources mediate CMC-specific mental health effects.

METHODS

Data were obtained from a population-based, cross-sectional survey of 5078 non-institutionalized, late middle-aged and older Dutch persons. The predictors were 16 types of CMCs, including all major chronic medical diseases as well as impairment of hearing, vision, and cognition. The outcomes were assessed in terms of psychological distress as measured by the Hospital Anxiety and Depression Scale. Two aspects of disability were measured (namely, physical and role functioning) and also three psychosocial resources (namely, mastery, self-efficacy and social support).

RESULTS

Level of psychological distress varied across type of CMC. Hearing impairment, neurological disease, vision impairment, and lung and heart disease had particularly strong associations with distress. The level of distress in patients with hearing impairment was 0.45 standard deviation higher than in those without hearing impairment (adjusted for demographics and all other CMCs). Roughly similar patterns of association were found between type of CMC and disability, and also, but to a lesser extent, mastery and self-efficacy. Stepwise multiple regression revealed that type of CMC accounted for 9% of the variance in distress initially, but this fell to 1% after the variance due to disability, mastery and self-efficacy was taken out. Social support was not a mediator. Disability and psychosocial resources accounted for 13% and 14% of the variance in distress, respectively.

CONCLUSION

These results support the conventional wisdom that it is not the nature of the condition that determines psychological distress, but instead the severity of the disability and loss of psychological resources associated with the condition on the one hand and the psychological characteristics of the patient on the other.

Direct and buffer effects of social support and personal coping resources in individuals with arthritis

The direct and buffer effects of various aspects of social support and personal coping resources on depressive symptoms were examined. The study concerned a community-based sample of 1690 older persons aged 55-85 yrs, of whom 719 had no chronic disease, 612 had mild arthritis and 359 had severe arthritis. Persons with arthritis reported more depressive symptoms than persons with no chronic diseases. Irrespective of arthritis, the presence of a partner, having many close social relationships, feelings of mastery and a high self-esteem were found to have direct, favourable effects on psychological functioning. Mastery, having many diffuse social relationships, and receiving emotional support seem to mitigate the influence of arthritis on depressive symptoms, which is in conformity with the buffer hypothesis. Favourable effects of these variables on depressive symptomatology were only, or more strongly, found in persons suffering from severe arthritis.

Does family support buffer the impact of specific chronic diseases on mobility in community-dwelling elderly?

The present study explores whether different structural (presence of partner and children) and functional (amounts of instrumental and emotional support provided by partner and children) family characteristics buffer the influence of chronic diseases on physical functioning. Logistic regression analyses were performed in a population-based sample of 2830 community-dwelling elderly people with chronic diseases as independent variable, and mobility difficulties as dependent variable, for separate strata of family characteristics. The presence of buffer effects was ascertained by comparing the associations between disease variables and mobility difficulties across the strata of family characteristics, using the odds ratios and 95% confidence intervals. Living together with a partner appears to buffer the association between the presence of one chronic disease and mobility difficulties, but no such effect is present among subjects with more than one disease. Regarding specific chronic diseases, partner presence has a beneficial influence only on the association between stroke and mobility difficulties, regardless of whether the partner provides little or much support. For patients with chronic non-specific lung disease (asthma, chronic bronchitis or pulmonary emphysema), a small amount of instrumental support (help with daily chores in and around the house) received from the partner is associated with a higher risk for mobility difficulties, compared to patients who receive a large amount of instrumental support and to patients who are not living with a partner. Neither the presence of children, nor the amounts of support received from them, influences associations between specific chronic diseases and mobility difficulties. The present study provides limited evidence supporting a buffer effect of family characteristics on the association between chronic diseases and mobility. Only in elderly people with a relatively low burden of disease does family support mitigate the adverse effects of disease on physical functioning.

Self-reports and general practitioner information on the presence of chronic diseases in community dwelling elderly. A study on the accuracy of patients' self-reports and on determinants of inaccuracy

OBJECT

The object of the study is to investigate the (in)accuracy of patients' self-reports, as compared with general practitioners' information, regarding the presence of specific chronic diseases, and the influence of patient characteristics.

METHODS

Questionnaire data of 2380 community-dwelling elderly patients, aged 55-85 years, on the presence of chronic non-specific lung disease, cardiac disease, peripheral atherosclerosis, stroke, diabetes, malignancies, and osteoarthritis/rheumatoid arthritis were compared with data from the general practitioners, using the kappa-statistic. Associations between the accuracy of self-reports and patient characteristics were studied by multiple logistic regression analyses.

RESULTS

Kappa's ranged from 0.30 to 0.40 for osteoarthritis/rheumatoid arthritis and atherosclerosis, to 0.85 for diabetes mellitus. In the multivariate analyses, educational level, level of urbanization, deviations in cognitive function, and depressive symptomatology had no influence on the level of accuracy. An influence of gender, age, mobility limitations, and recent contact with the general practitioner was shown for specific diseases. For chronic non-specific lung disease, both "underreporting" and "overreporting" are more prevalent in males, compared to females. Furthermore, males tend to overreport stroke and underreport malignancies and arthritis, whereas females tend to overreport malignancies and arthritis. Both overreporting and underreporting of cardiac disease are more prevalent as people are older. Also, older age is associated with overreporting of stroke, and with underreporting of arthritis. The self-reported presence of mobility limitations is associated with overreporting of all specific diseases studied, except for diabetes mellitus, and its absence is associated with underreporting, except for diabetes mellitus and atherosclerosis. Recent contact with the general practitioner is associated with overreporting of cardiac disease, atherosclerosis, malignancies and arthritis, and with less frequent underreporting of diabetes and arthritis.

CONCLUSIONS

Results suggest that patients' self-reports on selected chronic diseases are fairly accurate, with the exceptions of atherosclerosis and arthritis. The associations found with certain patient characteristics may be explained by the tendency of patients to label symptoms, denial by the patient, or inaccuracy of medical records.

Psychological status among elderly people with chronic diseases: does type of disease play a part?

Psychological status, including depressive symptoms, anxiety, and mastery, was measured in a community-based sample of 3,076 persons aged 55 to 85 with various chronic diseases. Strong, linear associations were found between the number of chronic diseases and depressive symptoms and anxiety, indicating that psychological distress among elderly people is more apparent in the presence of (more) diseases. Furthermore, in contrast to general assumptions that mastery is a relatively stable state, our results indicate that mastery is affected by having chronic diseases. The 8 groups of chronically ill patients (with cardiac disease, peripheral atherosclerosis, stroke, diabetes, lung disease, osteoarthritis, rheumatoid arthritis, or cancer) did differ in their associations with psychological distress. Psychological distress is most frequently experienced by patients with osteoarthritis, rheumatoid arthritis, and stroke, whereas diabetic and cardiac patients appear to be the least psychologically distressed. Differences in disease characteristics, such as functional incapacitation and illness controllability, may partly explain these observed psychological differences across diseases.