Geertrudis A.M. van den Bos

Causes and consequences of comorbidity: a review.

A literature search was carried out to identify and summarize the existing information on causes and consequences of comorbidity of chronic somatic diseases. A selection of 82 articles met our inclusion criteria. Very little work has been done on the causes of comorbidity. On the other hand, much work has been done on consequences of comorbidity, although comorbidity is seldom the main subject of study. We found comorbidity in general to be associated with mortality, quality of life, and health care. The consequences of specific disease combinations, however, depended on many factors. We recommend more etiological studies on shared risk factors, especially for those comorbidities that occur at a higher rate than expected. New insights in this field can lead to better prevention strategies. Health care workers need to take comorbid diseases into account in monitoring and treating patients. Future studies on consequences of comorbidity should investigate specific disease combinations.

Original articleCauses and consequences of comorbidity: A review

A literature search was carried out to identify and summarize the existing information on causes and consequences of comorbidity of chronic somatic diseases. A selection of 82 articles met our inclusion criteria. Very little work has been done on the causes of comorbidity. On the other hand, much work has been done on consequences of comorbidity, although comorbidity is seldom the main subject of study. We found comorbidity in general to be associated with mortality, quality of life, and health care. The consequences of specific disease combinations, however, depended on many factors. We recommend more etiological studies on shared risk factors, especially for those comorbidities that occur at a higher rate than expected. New insights in this field can lead to better prevention strategies. Health care workers need to take comorbid diseases into account in monitoring and treating patients. Future studies on consequences of comorbidity should investigate specific disease combinations.

Cancer and caregiving : The impact on the caregiver's health

A diagnosis of cancer affects not only the patient but also their significant others, especially when a lot of care tasks are involved. Some caregivers perceive the care as a burden, while others consider it a challenge. In this article, findings concerning the impact of cancer caregiving on informal caregivers will be described. No consistent results are reported, and little is known about patterns of caregiving changes in relation to the course of the patients illness. Attention will be given to factors which have been identified as influencing the course and consequences of caregiving. These factors form the basis of a conceptual research model for caregivers of cancer patients. As cancer progresses, care tasks are generated, which can be perceived by the caregiver as either negative (i.e. burden) or positive. Furthermore, these caregiver experiences may lead to negative as well as positive effects on the caregivers health and these relationships can be assumed to be bidirectional.

Determinants of caregiving experiences and mental health of partners of cancer patients

Research regarding informal caregiving showed considerable individual variation in responses to cancer caregiving. The current longitudinal study examined determinants of caregiver outcomes in terms of caregiver experiences at 3 months and caregivers mental health at 6 months after hospital discharge. It included both negative and positive dimensions of caregiving outcomes.

The development of a handicap assessment questionnaire: the Impact on Participation and Autonomy (IPA)

Objective: To report on the feasibility and psychometric properties in terms of homogeneity and construct validity of a newly developed handicap questionnaire focusing on person-perceived handicaps: the Impact on Participation and Autonomy (IPA). Design: Cross-sectional. Setting, subjects and outcome measure: One hundred consecutive individuals from the outpatient clinic of the department of rehabilitation of an academic hospital administered the new questionnaire IPA. Results: The results show good homogeneity and construct validity of the IPA. Factor analysis showed that the scale consists of four factors, explaining 68% of the total variance: social relationships, autonomy in self-care, mobility and leisure, and family role. Homogeneity of the four subscales was considered good, Cronbachs α ranged from 0.84 (family role) to 0.87 (social relationships). Feasibility in terms of the number of missing values and administration time needed was satisfactory. Conclusion: The first results suggest that the IPA promises to be a useful handicap questionnaire. Further research is needed to establish test–retest reliability, convergent validity and responsiveness to change.

Measuring functional status: Cross-sectional and longitudinal associations between performance and self-report (Zutphen Elderly Study 1990–1993)

We investigated cross-sectional as well as longitudinal associations between performance-based measures of functional status and self-reported measures of functional status. In the Zutphen Elderly Study, 494 men, born between 1900 and 1920, were examined in 1990, of whom 303 were reexamined in 1993. A performance score was constructed on the basis of four tests: standing balance, walking speed, ability to rise from a chair, and external shoulder rotation. Self-reported functional status was based on disabilities in basic activities of daily living, mobility, and instrumental activities of daily living. A hierarchic disability scale was constructed. Cross-sectional correlation coefficients between the performance score and the disability scale were 0.22 in 1990 and 0.39 in 1993. Correlations were highest between the test for walking speed and self-reported mobility and IADL, and between the test for external shoulder rotation and self-reported disabilities in basic activities of daily living. The correlation between the 3-year changes in performance and in self-report was 0.20 (p < 0.001). Both performance and self-report at baseline predicted performance and self-report after 3 years. Performance-based measures of functional status are cross-sectionally and longitudinally associated at modest levels with self-reported disabilities. Performance measures and self-reported measures are complementary, but do not measure the same construct.

Measuring both negative and positive reactions to giving care to cancer patients: psychometric qualities of the Caregiver Reaction Assessment (CRA)

The Caregiver Reaction Assessment Scale (CRA) is an instrument designed to assess specific aspects of the caregiving situation, including both negative and positive dimensions of caregiving reactions. This paper addresses the psychometric qualities of the CRA in a multicenter study among partners of colorectal cancer patients (n = 181). No problems in feasibility were observed. Five dimensions of caregiver reactions were identified through exploratory factor analysis: the impact of caregiving on disrupted schedule, financial problems, lack of family support, health problems and the impact of caregiving on caregivers self-esteem. Reliability analyses showed that standardized Cronbachs alphas varied between 0.62 and 0.83 for the separate subscales, indicating sufficient internal consistencies. Construct validity was supported. The CRA proves to be a feasible, reliable and valid instrument for assessing both negative and positive reactions to caregiving among partners of patients with cancer.

Comorbidity in patients with diabetes mellitus: impact on medical health care utilization.

BackgroundComorbidity has been shown to intensify health care utilization and to increase medical care costs for patients with diabetes. However, most studies have been focused on one health care service, mainly hospital care, or limited their analyses to one additional comorbid disease, or the data were based on self-reported questionnaires instead of health care registration data. The purpose of this study is to estimate the effects a broad spectrum of of comorbidities on the type and volume of medical health care utilization of patients with diabetes.MethodsBy linking general practice and hospital based registrations in the Netherlands, data on comorbidity and health care utilization of patients with diabetes (n = 7,499) were obtained. Comorbidity was defined as diabetes-related comorbiiabetes-related comorbidity. Multilevel regression analyses were applied to estimate the effects of comorbidity on health care utilization.ResultsOur results show that both diabetes-related and non diabetes-related comorbidity increase the use of medical care substantially in patients with diabetes. Having both diabeterelated and non diabetes-related comorbidity incrases the demand for health care even more. Differences in health care utilization patterns were observed between the comorbidities.ConclusionNon diabetes-related comorbidity increases the health care demand as much as diabetes-related comorbidity. Current single-disease approach of integrated diabetes care should be extended with additional care modules, which must be generic and include multiple diseases in order to meet the complex health care demands of patients with diabetes in the future.

Beyond disability: perceived participation in people with a chronic disabling condition

Objective: To describe the impact of a chronic disabling condition on participation and to identify variables that may explain perceived restrictions in participation. Study design: Cross-sectional. Setting: People were recruited from the outpatient clinics of two rehabilitation centres and the rehabilitation department of an academic hospital. Subjects: One hundred and twenty-six people from five diagnostic groups (neuromuscular disease, rheumatoid arthritis, spinal cord injury, stroke, fibromyalgia) participated in the study. Method: The IPA (Impact on Participation and Autonomy) questionnaire was used to describe perceived participation. Explanatory variables were studied in terms of sociodemographic factors and health status variables. Results: Some restrictions in participation seem comparable among diagnostic groups, others are specific to one or two groups. People with stroke, rheumatoid arthritis or fibromyalgia perceived more restrictions in participation than people with spinal cord injury or neuromuscular disorders. Emotional distress was the most important factor contributing to restrictions in participation. Conclusions: Perceived participation remains a complex concept in which many factors are involved. To make a contribution to meaningful participation of people with a chronic disabling condition, rehabilitation treatment should address physical, social, emotional and environmental aspects.

Modeling the Future Burden of Stroke in the Netherlands Impact of Aging, Smoking, and Hypertension

Background and Purpose— In the near future, the number of stroke patients and their related healthcare costs are expected to rise. The purpose of this study was to estimate this expected increase in stroke patients in the Netherlands. We sought to determine what the future developments in the number of stroke patients due to demographic changes and trends in the prevalence of smoking and hypertension in terms of the prevalence, incidence, and potential years of life lost might be. Methods— A dynamic, multistate life table was used, which combined demographic projections and existing stroke morbidity and mortality data. It projected future changes in the number of stroke patients in several scenarios for the Dutch population for the period 2000 to 2020. The model calculated the annual number of new patients by age and sex by using incidence rates, defined by age, sex, and major risk factors. The change in the annual number of stroke patients is the result of incident cases minus mortality numbers. Results— Demographic changes in the population suggest an increase of 27% in number of stroke patients per 1000 in 2020 compared with 2000. Extrapolating past trends in the prevalence of smoking behavior, hypertension, and stroke incidence resulted in an increase of 4%. Conclusions— The number of stroke patients in the Netherlands will rise continuously until the year 2020. Our study demonstrates that a large part of this increase in the number of patients is an inevitable consequence of the aging of the population.