Socio-economic gradients in the presence of musculoskeletal and other chronic diseases: results from a cross-sectional study in the Netherlands.

Socio-economic gradients in occurrence of diseases have been reported for many chronic conditions. However, whether the magnitude of socio-economic gradients differs across diseases and the extent to which lifestyle mediates such relationships are not known. Cross-sectional data from The National Monitor on Musculoskeletal System was used. Respondents (> 18 years) completed a questionnaire including gender, education, social status, lifestyle, and physician-diagnosed diseases. Logistic regressions investigated the relationship between education and the major chronic diseases (musculoskeletal diseases (MSKD), diabetes, cardiovascular (CVD), cancer, mental, respiratory, any disease). Next, analyses were repeated in individuals with potential to have paid work (i.e., those < 65 having paid work, being unemployed, or receiving living allowance (minimum income)). The mediating role of smoking and BMI between education and occurrence of diseases was assessed by testing indirect effects. From 8904 individuals (mean age 54 years, 46% male), 4378 (49%) had at least one disease. Gradients in occurrence of disease by education were present for all diseases except cancer and mental disease, with the strongest gradient in diabetes (OR 2.0 [95%CI 1.4;2.8]). Unemployment and especially living on minimum income were associated with increased odds to have MSKD and mental and respiratory disease, after adjusting for education. Smoking and obesity mediated part of the relationship between education and disease, with obesity playing more pronounced role. Association between deprivation and occurrence of all major chronic diseases is of comparable magnitude, with education having most consistent contribution. Our results support the notion of the generic (i.e., non-disease specific) mechanisms underlying socio-economic gradients in health.

Socioeconomic inequities in perceived health among patients with musculoskeletal disorders compared with other chronic disorders: results from a cross-sectional Dutch study.

OBJECTIVES: To explore the impact of socioeconomic factors on physical and mental health of patients with musculoskeletal disorders (MSKDs) and compare it across patients with other disorders. METHODS: A representative sample of the Dutch population (n=8904) completed a survey on sociodemographics, physician-diagnosed (co-) morbidities, and physical (physical component summary, PCS) and mental (mental component summary, MCS) subscales of SF-12 (outcome variables). Regression models were computed first in the total group of patients with MSKDs, with education, age, gender, origin and place of residence as independent variables, and, second, in individuals expected to have paid work, adding a variable on social status. Models were repeated for five other subgroups of chronic disorders (cardiovascular (CVD), diabetes, cancer, mental and respiratory) and for healthy individuals. RESULTS: MSKDs confirmed by a physician were reported by 1766 (20%) participants (mean age 59 years, 38% male), 547 (6%) respondents reported to have diabetes, 1855 (21%) CVD, 270 (3%) cancer, 526 (6%) mental disorders, 679 (8%) respiratory disorders and 4525 (51%) did not report any disease. In patients with MSKDs, (primary school vs university education (-5.3 (PCS) and -3.3 (MCS)) and having a state subsidy vs paid work (-5.3 (PCS) and -4.7 (MCS)) were consistently associated with worse physical and mental health. Gender was only relevant for PCS (female vs male -2.1). Comparable differences in health by education and social status were observed in the other diseases, except for cancer. CONCLUSIONS: Education and social status in MSKD have the same strong and independent association with health as in other chronic diseases. These health gradients are unfair and partly avoidable, and require consorted attention and action in and outside healthcare.

The association of pre-operative physical fitness and physical activity with outcome after scheduled major abdominal surgery.

We studied whether reported physical activity and measurements of fitness (hand, leg and inspiration) were associated with postoperative in-hospital mortality, length of stay and discharge destination in 169 patients after major oncological abdominal surgery. In multivariate analysis, adequate activity level (OR 5.5, 95% CI 1.4-21.9) and inspiratory muscle endurance (OR 5.2, 95% CI 1.4-19.1) were independently associated with short-term mortality, whereas conventional factors, such as age and heart disease, were not. Adequate activity level (OR 6.7, 95% CI 1.4-3.0) was also independently associated with discharge destination. The factors that were independently associated with a shorter length of hospital stay were as follows: absence of chronic obstructive pulmonary disease (HR 0.6, 95% CI 0.3-1.1); adequate activity level (HR 0.6, 95% CI 0.4-0.8); and inspiratory muscle strength (HR 0.6, 95% CI 0.5-0.9). For all postoperative outcomes physical activity and fitness significantly improved the predictive value compared with known risk factors, such as age and comorbidities. We conclude that pre-operative questionnaires of physical activity and measurements of fitness contribute to the prediction of postoperative outcomes.

Selective association of multiple sclerosis with infectious mononucleosis.

Previous studies have suggested an association between multiple sclerosis (MS) and infectious mononucleosis (IM) but data on the exact strength of this association or its selectivity have been conflicting. In this study we have evaluated the association between MS and a variety of common childhood infections and afflictions in a large population-based case-control study involving 2,877 MS cases and 2,673 controls in the Netherlands. We examined the frequency of different common infections and afflictions before the age of 25 and the age at which they occurred, using a self-administered questionnaire. The Odds ratios (ORs) for the occurrence of a variety of clinically manifest common childhood infections including rubella, measles, chicken pox and mumps before the age of 25 for MS cases versus controls ranged between 1.14 and 1.42, values similar to those for irrelevant probe variables used to reveal recall bias. In contrast, the OR for clinically manifest IM in MS cases versus controls, corrected for demographic variables, was 2.22 (95% confidence interval 1.73 - 2.86; P < 0.001). The average age of onset of IM in the population of MS cases (16.5 years) did not differ from controls (16.8 years). Our data confirm previous much smaller studies to show that the risk for MS is significantly enhanced by prior IM, and extend those previous data by showing that this association is far stronger than with other common childhood infections or afflictions.

The development and validation of a handicap questionnaire for children with a chronic illness.

INTRODUCTION: This paper describes the development and initial psychometric evaluation of the Handicap Scale for Children (HSC). This questionnaire is based on the London Handicap Scale (LHS), a valid and reliable utility instrument for measuring social participation in adults. METHODS: A multidisciplinary research group was involved in developing the HSC. The questionnaire was tested in 114 children with a chronic disease and 239 healthy children in the 8-18 age range. Relating the Health Utility Index Mark 3 (HUI3) attributes to corresponding HSC scores tested the assumption that a negative health status would lead to participation problems. RESULTS: Questionnaire development resulted in a five-dimension questionnaire: mobility, physical independence, daily activities, social integration and orientation. Each dimension included one item with a six-point response scale. A higher score indicates greater handicap. Feasibility testing with 10 children showed that none of the children experienced difficulties in filling in the questionnaire. Conceptual validity, measured by correlations between the dimensions of the HSC and HUI3, was satisfactory. As expected, moderate correlation coefficients between predefined pairs of HUI and HSC attributes were found; other correlation coefficients were low. Criterion validity was also satisfactory, as shown by large differences between the healthy and the chronically ill group and by several criteria within the chronically ill group. CONCLUSION: Based on this initial evaluation, the questionnaire seems feasible and valid for use with children in the age range 8-18 years.

Quality of life and work in patients with rheumatoid arthritis and ankylosing spondylitis of working age.

OBJECTIVE: To investigate the relationship between work and quality of life (QOL) in patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) aged 16-59. METHODS: 1056 patients with RA and 658 with AS were included in the study. Data were obtained by postal questionnaire, which included several generic and disease related QOL instruments. Separate dimensions and physical and mental summary scores from the SF-36 were compared. Stepwise multiple regression was performed to study the relationship between work and physical and mental health related QOL, including disease related factors, coping, and fatigue. RESULTS: Physical health related QOL was reported to be worse, and mental health related QOL better, in RA than in AS in people of working age. No differences between RA and AS were found in somatic pain, physical role functioning, social functioning, emotional role functioning, vitality, or general health perception; nor were there any significant differences in fatigue and behavioural coping styles. Work was positively associated with physical health related QOL in both groups and, after disease characteristics, was the most important determinant. No association was found with mental health related QOL. CONCLUSIONS: Although physical health related QOL was worse in patients with RA, the impact on several dimensions of health related QOL in patients with RA and AS of working age under rheumatological care was comparable. Patients with RA and AS experienced similar limitations in physical role functioning, including work. Work is an important independent external determinant of physical health related QOL, but not of mental health related QOL.

Employment perspectives of patients with ankylosing spondylitis.

OBJECTIVES: To assess the labour market position of patients with ankylosing spondylitis (AS) in relation to disease duration and to identify potential factors in relation to withdrawal from the labour force. METHODS: A cross sectional mail survey was conducted among 658 patients with AS. Participation in the labour force was defined as having a paid job. The independent effect of duration of disease was examined by an indirect method of standardisation. A broad variety of risk factors were examined separately and in a combined analysis, including sociodemographic factors, disease related variables, coping styles, and work related factors. Attributable and preventable fractions were calculated from the combined analyses to assess the relative importance of the contributing factors. RESULTS: Probability of participation in the labour force was similarly reduced in patients with AS with different durations of disease. Pacing to cope with limitations was the most relevant factor in increasing the risk of withdrawal from the labour force, accounting for 73% of withdrawals. Coping with limitations by often seeking creative solutions, high disease activity, increased age, and insufficient support from colleagues or management were also positively associated with withdrawal from the labour force. Technical or ergonomic adjustments of the workplace, working in large companies, and coping with dependency style through frequent acceptance were negatively associated. Of these factors, technical or ergonomic adjustment was the most relevant in terms of reducing the risk. CONCLUSION: Sociodemographic factors, disease related factors, coping styles, and work related factors contribute simultaneously to withdrawal from the labour force.

Work factors and behavioural coping in relation to withdrawal from the labour force in patients with rheumatoid arthritis.

OBJECTIVE: To assess separate and combined effects of work factors and behavioural coping in relation to withdrawal from the labour force among patients with rheumatoid arthritis (RA). METHODS: A cross sectional study was conducted in a Dutch nationwide random sample of 720 patients with RA. Information about work factors and behavioural coping was collected by a self-administered postal questionnaire. A broad variety of work factors and coping styles were evaluated separately and in combination using multivariate logistic regression analyses, controlling for sociodemographic and disease related variables. Attributable and preventable fractions were calculated from the combined analyses to assess the relative importance of the contributing factors. RESULTS: Additional job training, equal career opportunities, letting the disease influence the choice of the current job position, and informing colleagues about having the disease were negatively associated with withdrawal from the labour force. The most relevant factor in terms of decreasing the risk was adjusting job demands which accounted for 63% of the patients still in the labour force. Decreasing activities and diverting attention in order to cope with pain, and pacing in order to cope with limitations were the coping styles which were positively associated with withdrawal from the labour force. The most relevant factor in terms of increasing the risk of withdrawal was pacing which accounted for 67% of the withdrawals. CONCLUSION: Work factors are potentially important modifiable risk factors for withdrawal from the labour force in patients with RA. Behavioural coping is also relevant.

Labour force participation among patients with rheumatoid arthritis.

OBJECTIVES: To assess work history and labour force participation among patients with rheumatoid arthritis (RA) in the Netherlands. METHODS: A random sample of 1056 patients with RA aged 16-59 years from 17 rheumatology practices in the Netherlands was examined. Data on disease status and outcome were obtained by a questionnaire including standardised instruments, such as the Rapid Assessment of Disease Activity in Rheumatology (RADAR) and RAND-36 questionnaires. Labour force participation was defined as having a paid job. RESULTS: Of the study group with a mean disease duration of 12 years, 35.7% held a paid job (men 56.7%; women 27.7%). When standardised for age, sex, and educational level, the labour force participation of patients with RA was 61.2% compared with 65.5% for the general population, which was not statistically significant. Disease duration of six years and more was negatively associated with labour force participation. CONCLUSIONS: After controlling for the confounding effects of age, sex, and education, the labour force participation of patients with RA in the Netherlands is only slightly lower than that of the general population.

Chronicity of back problems during working life.

STUDY DESIGN: A follow-up study of a cohort of 444 patients aged 16 to 59 years who consulted with their general practitioners (GPs) in 1987-1988 for an incident episode of back pain. OBJECTIVES: To determine the proportion of patients with back pain in whom chronic back problems develop after a follow-up of 7 years, to compare health outcomes and labor force participation of patients with and without chronic back problems and to identify determinants of chronicity. SUMMARY OF BACKGROUND DATA: The incidence and prevalence of back pain are very high. A large proportion of the costs related to medical consumption, absence from work, and disability are probably caused by chronic back problems. It is unknown what proportion of back problems become chronic, especially after a long follow-up period, and which factors can predict chronicity. METHODS: Data on the course of the symptoms and medical consumption from the period between 1987-1988 and 1991 were gathered retrospectively. Data on several health outcomes, including LFP, and data on some work characteristics were collected prospectively in 1991. A more extensive data set on health outcomes including psychologic status and working situation was collected in 1994. RESULTS: Chronic back problems developed in 28% of the patients. These patients reported more pain, higher levels of medical resource consumption, worse health outcomes, and lower labor force participation. Episodes of back pain before 1987-1988, severe pain in 1991, and disability score in 1991 were positively associated with chronicity in 1994, difficulties with job performance in 1991, and frequent stooping in the subgroup of patients who held a paying job in the follow-up period. CONCLUSIONS: Even after a follow-up of 7 years, the proportion of people with chronic back problems was high. The consequences for quality of life, labor force participation, and consumption of medical resources are clear. Further research is necessary to examine determinants and ways to prevent chronicity.

The European health potential: what can we learn from each other?

In this paper global differences in health between the 12 countries of the European Union are compared and related to variations in so-called determinants of health, especially socio-economic and life style factors and characteristics of the health care system in each country. This leads to two main conclusions. The first conclusion is that the health differences that exist within the European Union can only be partially explained by variations in determinants of health. Still, the comparison offers intriguing clues for improving health, containing cost and further research in the European Union. The second conclusion is that considerable data on health and determinants of health are collected in each country, but that international comparability is still limited. The ongoing activities in the standardization of European data collection need our full support.

Leukemia risk following Hodgkin's disease: relation to cumulative dose of alkylating agents, treatment with teniposide combinations, number of episodes of chemotherapy, and bone marrow damage.

PURPOSE: The development of leukemia is one of the most serious long-term complications of modern treatment for Hodgkin's disease (HD). This study was undertaken to examine the relation between risk of leukemia and various treatment factors (including cumulative dose of cytostatic drugs and interaction with radiotherapy [RT]), while also assessing the effect of treatment-induced bone marrow damage. PATIENTS AND METHODS: We conducted a case-control study in a cohort of 1,939 patients treated for HD between 1966 and 1986 in the Netherlands. Detailed information from the medical records was obtained for 44 cases of leukemia and 124 matched controls, in whom leukemia had not developed. RESULTS: The cumulative dose of mechlorethamine was the most important factor in determining leukemia risk. As compared with patients who received RT alone, patients treated with six or fewer cycles of combinations including nitrogen mustard (mechlorethamine) and procarbazine had an eightfold increased risk of developing leukemia (P = .08), while patients who received more than six of such cycles had a greater than 40-fold excess risk (P < .001). Treatment with lomustine or a combination of teniposide and cyclophosphamide also significantly increased the risk of leukemia. Patients who had received chemotherapy (CT) during two or more time periods had a nearly 40-fold increased risk of leukemia as compared with patients treated only once. The extent of RT did not further increase leukemia risk among patients who also received CT. A significantly increased risk of leukemia was found among patients with low platelet counts, both in response to initial therapy and during follow-up. Patients who experienced 2 or more half-year periods with platelet counts less than 75 x 10(6)/mL had an approximately fivefold risk of developing leukemia, and a similar risk increase was found for patients who responded to initial treatment with a > or = 70% decrease of platelet counts (as compared with patients who had a < or = 50% decrease). CONCLUSION: In addition to mechlorethamine, lomustine and teniposide combinations were also linked to an elevated risk of developing leukemia. Since the number of CT episodes was found to be a strong determinant of leukemia risk, it is important that new therapies for HD continue to yield high initial cure rates. Further studies are warranted to investigate whether patients at high risk for developing leukemia may be identified from the response of their platelets to initial therapy for HD.