Socioeconomic status and smoking: analysing inequalities with multiple indicators

BACKGROUND AND AIMS: Socioeconomic differences in smoking have been well established. While previous studies have mostly relied on one socioeconomic indicator at a time, this study examined socioeconomic differences in smoking by using several indicators that reflect different dimensions of socioeconomic position. DATA AND METHODS: Data derive from Helsinki Health Study baseline surveys conducted among the employees of the City of Helsinki in 2000 and 2001. The data include 6243 respondents aged 40-60 years (response rate 68%). Six socioeconomic indicators were used: education, occupational status, household income per consumption unit, housing tenure, economic difficulties and economic satisfaction. Their associations with current smoking were examined by fitting sequential logistic regression models. RESULTS: All socioeconomic indicators were strongly associated with smoking among both men and women. When the indicators were examined simultaneously their associations with smoking attenuated, especially when education and occupational status were considered together, and when income and housing tenure were introduced into the models already containing education and occupational status. After mutual adjustment for all socioeconomic indicators, housing tenure and economic satisfaction remained associated with smoking in men. In women, all indicators except income and economic difficulties were inversely associated with smoking after adjustments. CONCLUSIONS: Smoking was associated with structural, material as well as perceived dimensions of socioeconomic disadvantage. Attempts to reduce smoking among the socioeconomically disadvantaged need to target several dimensions of socioeconomic position.     

Does survey non-response bias the association between occupational social class and health?

AIMS: A non-response rate of 20-40%is typical in questionnaire studies. The authors evaluate non-response bias and its impact on analyses of social class inequalities in health. METHODS: Set in the context of a health survey carried out among the employees of the City of Helsinki (non-response 33%) in 2000-02. Survey response and non-response records were linked with a personnel register to provide information on occupational social class and long sickness absence spells as an indicator of health status. RESULTS: Women and employees in higher occupational social classes were more likely to respond. Non-respondents had about 20-30% higher sickness absence rates. Relative social class differences in sickness absence in the total population were similar to those among either respondents or non-respondents. CONCLUSIONS: In working populations survey non-response does not seriously bias analyses of social class inequalities in sickness absence and possibly health inequalities more generally.     

Pathways between socioeconomic determinants of health

STUDY OBJECTIVE: Many previous studies on socioeconomic inequalities in health have neglected the causal interdependencies between different socioeconomic indicators. This study examines the pathways between three socioeconomic determinants of ill health. DESIGN, SETTING, AND PARTICIPANTS: Cross sectional survey data from the Helsinki health study in 2000 and 2001 were used. Each year employees of the City of Helsinki, reaching 40, 45, 50, 55, and 60 years received a mailed questionnaire. Altogether 6243 employees responded (80% women, response rate 68%). Socioeconomic indicators were education, occupational class, and household income. Health indicators were limiting longstanding illness and self rated health. Inequality indices were calculated based on logistic regression analysis. MAIN RESULTS: Each socioeconomic indicator showed a clear gradient with health. Among women half of inequalities in limiting longstanding illness by education were mediated through occupational class and household income. Inequalities by occupational class were largely explained by education. A small part of inequalities for income were explained by education and occupational class. For self rated health the pathways were broadly similar. Among men most of the inequalities in limiting longstanding illness by education were mediated through occupational class and income. Part of occupational class inequalities were explained by education. Two thirds of inequalities by income were explained by education and occupational class. CONCLUSIONS: Parts of the effects of each socioeconomic indicator on health are either explained by or mediated through other socioeconomic indicators. Analyses of the predictive power of socioeconomic indicators on health run the risk of being fruitless, if interrelations between various indicators are neglected.     

Occupational categories and sickness absence certified as attributable to common diseases

BACKGOUND: This paper focuses on the relationship between sickness absence rates certified as attributable to common (non-work-related) diseases and occupational categories. METHODS: A cohort of 2,909 workers from an urban bus company was analysed from 1994 to 1996 (8,388.7 person-years), who reported 2,893 non-work-related sickness absence spells of three days or more (78% of all sickness absence spells in the period). Rates of sickness absence were calculated and an extension of the Andersen-Gill approach to proportional hazards modelling was used to adjust covariables. RESULTS: Assistant staff (35.63 per 100 person-years), and bus drivers (37.23) had the highest incidence rates. After adjusting for demographic variables, employment duration and health status, it was found that all occupational categories had a significant rate ratio (RR) in comparison to the manager category. The strongest positive associations were found among bus drivers (RR = 2.45; 95% CI: 1.52-3.97), assistant staff (RR = 2.57; 1.67-3.94), and technical staff (RR = 2.42; 1.57-3.74). CONCLUSION: Occupational category was an important predictor of sickness absence incidence certified as attributable to common disease. Further research on the associations between working conditions and sickness absence needs to take into account the distinction between sickness absences due to work-related diseases and those due to common diseases.     

Register-based study among employees showed small nonparticipation bias in health surveys and check-ups

OBJECTIVES: To examine nonparticipation to a questionnaire survey and occupational health check-ups by sociodemographic variables and health status, measured by medically confirmed sickness absence, and whether the associations between other study variables and participation were affected by health status. STUDY DESIGN AND SETTING: Questionnaire surveys and health check-ups were conducted among the City of Helsinki employees. Sample information was derived from the employer's personnel register and analyzed by participation and giving consent to link the data to external administrative registers. RESULTS: Participation to the questionnaire survey was more common among the older, higher occupational classes, those with higher income, permanent employment, and those with no absence due to medically confirmed sickness. Among women in particular, the differences were small. Consent giving followed generally similar patterns than survey response. Nonparticipation to health check-ups was related to low income and temporary employment contract. In both questionnaire survey and health check-ups, associations between other study variables and participation were not affected by health status. CONCLUSIONS: Questionnaire surveys and health check-ups were broadly representative of the target population. Associations between other study variables and participation did not differ by health status. This suggests that even when the data are not fully representative associations between the study variables need not to be biased.     

A study of absence rates in male and female employees working in occupations of equal status

The objective of this study was to investigate the extent towhich occupational status and age influence absence rates inmale and female employees. This involved collection of datafor absences of one or more calendar days, including the lengthof absence and the location, age, occupational status and genderof the worker. This information was supplied by personnel departmentson standardized forms. The study took place in three occupationalgroups in two organizations with equal work status for men andwomen, located in England, Scotland and Northern Ireland. Intotal, we studied 2561 workers (77.8% male, 22.2% female) inemployment during the three months between April and July 1992.More women than men took time off work in the study period.Female absence exceeded male absence for spells of absence inratios between 1.3:1 and 1.5:1, and for days in ratios between1.2:1 and 1.9:1; age standardization removed the differencesin spell rates (in all but one group) and total absence (days).Both men and women took fewer but longer spells of absence withincreasing age. Men were more likely to take spells lastingmore than one day, but women took more multiple single-day spells.Relative job status affected absence rates, with professionalstaff taking less absence than support staff. In this workforcecontrolled for occupation, significant differences in crudeabsence rates were observed between males and females. Age standardizationexplained the difference in spell rates in most groups. Thissuggests that there is little true difference in absence ratesand highlights the importance of age standardization in suchstudies.     

Influence of individual and neighbourhood socioeconomic status on mortality among black,Mexican-American,and white women and men in the United States

STUDY OBJECTIVE:s: This study examines the influence of individual and neighbourhood socioeconomic status (SES) on mortality among black, Mexican-American, and white women and men in the US. The authors had three study objectives. Firstly, they examined mortality rates by both individual level SES (measured by income, education, and occupational/employment status) and neighbourhood level SES (index of neighbourhood income/wealth, educational attainment, occupational status, and employment status). Secondly, they examined whether neighbourhood SES was associated with mortality after controlling for individual SES. Thirdly, they calculated the population attributable risk to estimate the reduction in mortality rates if all women and men lived in the highest SES neighbourhoods. DESIGN: National Health Interview Survey (1987-1994), linked with 1990 census tract (neighbourhood proxy) and mortality data through 1997. SETTING/PARTICIPANTS: Nationally representative sample of 59 935 black, 19 201 Mexican-American, and 344 432 white men and women (six gender and racial/ethnic groups), aged 25-64 at interview. MAIN RESULTS: Mortality rates for all six gender and racial/ethnic groups were two to four times higher for those with the lowest incomes (lowest quartile) who lived in the lowest SES neighbourhoods (lowest tertile) compared with those with the highest incomes who lived in the highest SES neighbourhoods. For the six groups, the age adjusted mortality risk associated with living in the lowest SES neighbourhoods ranged from 1.43 to 1.61. The mortality risk decreased but remained significant (p values <.05) after adjusting for each of the three individual measures of SES, with the exception of Mexican-American women. Furthermore, the mortality risk associated with living in the lowest SES neighbourhoods remained significant after simultaneously adjusting for all three individual measures of SES for white men (p<0.001) and white women (p<0.05). Deaths would hypothetically be reduced by about 20% for each subgroup if everyone had the same death rates as those living in the highest SES neighbourhoods (highest tertile). CONCLUSIONS: Living in a low SES neighbourhood confers additional mortality risk beyond individual SES.     

The role of gender in long-term sickness absence and transition to permanent disability benefits. Results from a multiregister based,prospective study in Norway 1990-1995

BACKGROUND: The aim of the study was to identify predictors for the transition from long-term sickness absence into disability pension with a special focus on gender. METHODS: The study used data from a national database containing a 10% random sample of the Norwegian adult population (The KIRUT database). The study population were all individuals in the database who on 1 January 1990 were eligible for sick pay from the Norwegian National Insurance System: 83,398 men and 75,586 women. Individuals below 60 years with long-term sickness absence starting in 1990 and 1991 were identified, 6,434 men and 8,233 women, and followed up for three years. Background data were used as independent variables in a logistic regression of the probability for receiving disability pension during follow-up. RESULTS: Annual cumulative incidence of long-term sickness absence was 6.5% for women and 4.9% for men. During follow-up, 12.4% of the women and 12.6% of the men received disability pension. Among full-time employed women only 10.3% had become disability pensioners, while the corresponding proportion for women working part-time was 15.5%. For men the figures were 12.1% (full-time) and 18.1% (part-time). In the logistic regression of the whole sample the female odds ratio was insignificant. The dominant predictive factors for disability pension were age and duration of the sickness spells. Working part-time also increased the risk. Higher levels of education and having children below 7 years reduced the probability for disability pension. Separate regressions for men and women showed that the 'protective' effect of having small children only remained for women.     

Predictability of school absence for rate of sick leave

School absence was studied in all children in grade 8 (mean age 15 years) in the municipality of Link?ping during the school year 1969-70. The mean absence rate was 51 lessons per year. At the mean age of 27 years, 11-13 years later, information from the Swedish Social Insurance Office was collected in a 25% random sample. The median rate of sick leave was 5.3 days per year, the median number of sickness spells, 1.7 per year, the median number of days per sickness spells, 3.0 and the median income 77 000 SEK per year. Spearman rank correlation coefficients were calculated, separately for women and men, between absence rate in grade 8 on the one hand and different rates of sick leave and income on the other. For women, rs ranged between -0.06 and 0.14, for men, -0.16 to 0.21. Thus the predictive ability of school absence for rate of sick leave was found to be very low.     

Analysis of sickness absence among employees of four NHS trusts

OBJECTIVES: To determine the value of using routinely collected sickness absence data as part of a health needs assessment of healthcare workers. METHOD: Sickness absence records of almost 12900 NHS staff for one calendar year were analysed. Three measures of absence, the absence rate, the absence frequency rate, and the mean duration of absence, were assessed for the population and comparisons made between men and women, full and part time and different occupational groups of staff. Also, the main causes of sickness absence were found. RESULTS: Almost 60% of the study population had no spells of sickness absence in the year of study and almost 20% had only one spell of sickness absence. Female staff were more likely to have experienced sickness absence than male staff. Although absence due to conditions related to pregnancy were included in the analysis, the incidence of these was not sufficient to account for the higher rates of absence among female staff. In general, full time staff had greater rates of sickness absence than part time staff. 71% of all absences were of < 1 week duration. The main known causes of sickness absence were respiratory disorders, digestive disorders, and musculoskeletal disorders. CONCLUSIONS: The transition from units managed directly from the health board to trusts with individual responsibility for personnel issues at the time of data collection resulted in variations in the quality of data available for analysis. This together with the use of "dump" codes has influenced the quality of the analysis. However, such data should be available for analysis to tailor occupational health care to the needs of the population.

 

     

Socioeconomic status and type 2 diabetes in African American and non-Hispanic white women and men: evidence from the Third National Health and Nutrition Examination Survey

OBJECTIVES: This study examined the associations of poverty income ratio (PIR), education, and occupational status with type 2 diabetes prevalence among African American and non-Hispanic White (White) women and men aged 40 to 74 years. METHODS: We analyzed cross-sectional data from the Third National Health and Nutrition Examination Survey, controlling for age and examination-related variables. RESULTS: Among African American women, there was a strong, graded association between PIR and diabetes, which remained significant after other risk factors were adjusted for. All 3 variables were significantly associated with diabetes among White women. Among White men, only PIR was significantly associated with diabetes. Controlling for risk factors substantially attenuated these associations among White women. There were no significant associations for African American men. CONCLUSIONS: Socioeconomic status is associated with type 2 diabetes prevalence among women, but not consistently among men. Diabetes prevalence is more strongly associated with PIR than with education or occupational status. These associations are largely independent of other risk factors, especially among African American women. Economic resources should be addressed in efforts to explain and reverse the increasing prevalence of diabetes in the United States.     

Psychosocial factors at work and sickness absence in the Gazel cohort: a prospective study

OBJECTIVE: To test whether psychosocial factors at work are predictors of rates of sickness absence. METHODS: The study population consisted of middle aged men and women employed by the French national electricity and gas company (EDF-GDF) in various occupations and followed up since 1989 by annual self administered questionnaires and independent data obtained from the medical and personnel departments of EDF-GDF. The 1995 questionnaire provided information about three psychosocial work factors: psychological demands, decision latitude, and social support at work. Sick-ness absence data were provided by the company's social security department. The occurrence of spells and days of absence in the 12 months after completion of the 1995 questionnaire was studied. Potential confounding variables were age, smoking, alcohol, and marital status, assessed in the 1995 questionnaire, and educational level and occupation, assessed from data provided by the personnel department. This study was restricted to the 12,555 subjects of the initial cohort who were still working and answered the self administered questionnaire in 1995. RESULTS: Low levels of decision latitude were associated with more frequent and longer sickness absences among men and women. Low levels of social support at work increased the numbers of spells and days of absence among men only. These associations weakened after adjustment for potential confounding factors, but remained significant. CONCLUSION: The study indicates that psychosocial factors at work, especially decision latitude, are predictive of sickness absence.

 

     

A longitudinal study of changes in interactional justice and subsequent short-term sickness absence among municipal employees

Objectives:Level of perceived interactional justice has been shown to be associated with sickness absence, but less is known about the effects of changes in interactional justice. It is also unknown to what extent unmeasured, time-invariant differences contribute to the association. We investigated the association between interactional justice changes and subsequent short-term (1–3 days) sickness absences over a 12-year follow-up using between- and within-individual modeling among ageing municipal employees.Methods:The data was derived from Helsinki Health Study cohort with baseline survey in 2000–2002 (N=8960, response rate 67%) and follow-up surveys in 2007 and 2012 (response rates 79% and 83%, respectively). At baseline, participants were 40–60-year-old employees of the City of Helsinki, Finland. Sickness absences from the employer’s registry were linked with the responses (78%). The analytic sample was 2109 and 2070 individuals for between-individual and 4433 individuals and 8425 observations for within-individual associations.Results:Negative change in interactional justice was associated with an increased risk of short-term sickness absence in between-individual models after adjusting for age and gender. Adjustment for sickness absence history attenuated the association. In within-individual models, a negative change in perceived interactional justice was associated with an increased risk of short-term sickness absence spells [incidence rate ratios (IRR) 1.05 (95% confidence interval 1.01–1.09)]. This association was robust to adjustments for gender, age, health behaviors and sickness absence history.Conclusions:Paying attention to management principles – especially managerial behavior and treatment of employees to avoid the deterioration of the level of interactional justice – may provide a way of reducing self-certified short-term sickness absence spells.     

Occupational status, educational level, and the prevalence of carotid atherosclerosis in a general population sample of middle-aged Swedish men and women: results from the Malmö Diet and Cancer Study

The associations among educational level, occupational status, and atherosclerosis were investigated during 1992-1994 in a general population sample of 4,176 Swedish men and women. Carotid artery intima-media thickness (IMT) and carotid stenosis were determined by B-mode ultrasound. Socioeconomic differences in mean carotid IMT and odds ratios for carotid stenosis prevalence were estimated. In women, the associations among educational level, occupational status, and IMT were weak. In men, there was no association between education and IMT, while low occupational status was associated with a thicker IMT. Women with low education had an increased odds of carotid stenosis compared with women with high education (odds ratio (OR) = 2.04, 95% confidence interval (CI): 1.53, 2.73), while this pattern was weaker among men. Women in manual occupations had an increased odds of carotid stenosis compared with women in high- or medium-level nonmanual occupations (OR = 1.75, 95% CI: 1.29, 2.36), which could not be seen among men. After adjustment for risk factors, the association between IMT and occupational status in men disappeared, while the associations among educational level, occupational status, and carotid stenosis in women persisted. The results imply that the atherosclerotic process is associated with socioeconomic status in both sexes, and they also indicate the possibility of sex differences in the mechanisms connecting socioeconomic status to atherosclerosis.     

Relative weight and income at different levels of socioeconomic status

OBJECTIVES: We examined the association of relative weight with individual income at different levels of socioeconomic status among gainfully employed Finnish women and men. METHODS: We used a population-based survey including 2068 women and 2314 men with linked income data from a taxation register. Regression analysis was used to calculate mean income levels within educational and occupational groups. RESULTS: Compared with their normal-weight counterparts, obese women with higher education or in upper white-collar positions had significantly lower income; a smaller income disadvantage was seen in overweight women with secondary education and in manual workers. Excess body weight was not associated with income disadvantages in men. CONCLUSIONS: Obesity is associated with a clear income disadvantage, particularly among women with higher socioeconomic status.     

Social inequalities in mortality: changes in the relative importance of income, education and household size over a 27-year period

BACKGROUND: The aim of this paper was to measure socio-economic inequalities in mortality over a 27-year period, and estimate the simultaneous effects of education and income adjusted for changing proportions and potential confounders. METHODS: Census data in 1970, 1980 and 1990 with information about income, educational level and household size were linked to mortality records at the individual level and analysed with absolute mortality rates, Poisson regression (univariate and multivariate) and Relative Index of Inequality (RII). RESULTS: Mortality differences increased between income quartiles and educational groups as well as between singles and non-singles. RII between income quartiles increased from 1.6 to 3.6 for men and 1.7 to 2.7 for women while RII between the educational groups increased from 1.6 to 2.8 for men and 1.5 to 2.1 for women. However, RII derived from the adjusted multivariate regression analysis was 1.8 (men) and 1.9 (women) between the income groups in 1990 and 2.2 (men) and 1.7 (women) between the educational groups. In the 1990s current income was more important than previous income, and the rate ratios (RR) increased for groups dropping into the lowest income quartile between two censuses. CONCLUSION: Low education and single status have become relatively more important risk factors for mortality over time. Confounder effects of education and household size could partly explain the seemingly large increase in inequalities between income groups. Results may also indicate a stronger reverse causation (poor health causing low income) over time.     

Multiple dimensions of socioeconomic position and obesity among employees: The Helsinki Health Study

OBJECTIVE: To examine socioeconomic differences in obesity using several different socioeconomic indicators, ranging from childhood socioeconomic environment and adult socioeconomic status to material resources and economic satisfaction. RESEARCH METHODS AND PROCEDURES: The data derived from the Helsinki Health Study baseline surveys in 2000 and 2001. Respondents to postal surveys were middle-aged employees of the City of Helsinki (4,975 women and 1,252 men, response rate 68%). Associations between eight socioeconomic indicators and obesity (BMI > or = 30 kg/m(2)), calculated from self-reported data, were examined by fitting a series of logistic regression models. RESULTS: In women, all socioeconomic indicators except household income and economic satisfaction were associated with obesity. Parental education and childhood economic difficulties, i.e., socioeconomic conditions in childhood, remained associated with obesity after adjusting for all indicators of current socioeconomic position. Indicators of adult socioeconomic status, own education and occupational class, were no longer associated with obesity when childhood socioeconomic conditions were adjusted for. Home ownership and economic difficulties were associated with obesity after full adjustments. In men, the findings paralleled those among women, but few associations reached statistical significance. DISCUSSION: Obesity was associated with several dimensions of socioeconomic position. Childhood socioeconomic disadvantage was associated with obesity independently of the various indicators of current socioeconomic position. Associations between obesity and both educational level and occupational class disappeared after adjustment for other indicators of socioeconomic position. This suggests that the variation observed in the prevalence of obesity by these key socioeconomic indicators may reflect differences in the related material resources.     

Occupational stress and incidence of sick leave in the Belgian workforce: the Belstress study

CONTEXT: Sick leave is a major problem in public health. The Karasek demands/control/social support/strain (JDCS) model has been largely used to predict a wide range of health outcomes and to a lesser extent sickness absence. STUDY OBJECTIVE: The aim of the study was to test the predictive power of the JDCS model in relation with one year incidence of sick leave in a large cohort of workers. DESIGN AND SETTING: Cohort study conducted between 1994 and 1998 in 25 companies across Belgium. PARTICIPANTS: A total of 20 463 workers aged 35 to 59 years were followed up for sick leave during one year after the baseline survey. OUTCOMES: The outcomes were a high sick leave incidence, short spells (>/=7 days), long spells (>/=28 days), and repetitive spells of sickness absence (>/=3 spells/year). MAIN RESULTS: Independently from baseline confounding variables, a significant association between high strained jobs with low social support and repetitive spells of sickness absence was observed in both sexes with odds ratios of 1.32 (99% CI, 1.04 to 1.68) in men and 1.61 (99% CI, 1.13 to 2.33) in women. In men, high strained jobs with low social support was also significantly associated with high sick leave incidence, and short spells of sick leave with odds ratios of 1.38 (99% CI, 1.16 to 1.64) and 1.22 (99% CI, 1.05 to 1.44) respectively. CONCLUSIONS: Perceived high strain at work especially combined with low social support is predictive of sick leave in both sexes of a large cohort of the Belgian workforce.     

Changes in leisure-time physical activity and subsequent sickness absence: A prospective cohort study among middle-aged employees

ObjectiveThe aim of this study was to examine how changes over time in leisure-time physical activity are associated with subsequent sickness absence.MethodsHelsinki Health Study cohort baseline questionnaire survey data were collected in 2000–2002 among 40–60-year-old employees of the City of Helsinki, Finland. A follow-up survey was conducted in 2007. 4182 (83% women) respondents were available for the analyses. Leisure-time physical activity was asked using identical questions in both surveys. Sickness absence data were derived from the employer's registers (mean follow-up time 2.8 years). Associations of changes over time in leisure-time physical activity with self-certified (≤ 3 days) and medically certified (> 3 days) sickness absence spells were examined, using Poisson regression analysis.ResultsInactive women and men who increased their physical activity to vigorously active had a significantly lower risk of both self-certified (RR = 0.80, 95% CI 0.65–0.97) and medically certified (RR = 0.63, 95% CI 0.49–0.83) subsequent sickness absence spells compared with the persistently inactive. The persistently active with vigorous intensity had the lowest risk of sickness absence. Adjusting for changes in physical health functioning attenuated but did not abolish the lowered risk found.ConclusionsFor reducing sickness absence more emphasis should be given to the potential contribution of vigorous physical activity.     

The influence of household work and of having children on sickness absence among publicly employed women in Sweden

AIM: To investigate whether family obligations influence the risk of sickness absence among female municipal employees in Sweden. METHODS: A 1-year prospective cohort study of 1464 female municipal employees <50 years of age in Sweden in 2000 was conducted using questionnaire responses and absence data from the employers' personnel records. The relative risk of having children <16 years of age in the home, marital status, household work, financial situation, working hours and work-family conflicts for repeated sick-leave spells (>/=4 spells) and long-term sickness absence (>/=28 days) were calculated by applying Poisson regression models. RESULTS: Women reporting financial strain or work-family conflicts were at elevated risk for long-term sickness absence. Having children was not a risk factor for repeated sick-leave spells or long-term sickness absence among married/cohabiting women. Single women with children had a two-fold greater risk of repeated sick-leave spells than single women without children. CONCLUSIONS: The findings suggest that the combination of gainful employment and children does not influence the risk of repeated sick-leave spells or long-term sickness absence among married/cohabiting publicly employed women. However, this was not true for single women with children, which indicates that their circumstances are particularly strained.