Psychological Symptoms in Late Adolescence and Long-Term Risk of Suicide and Suicide Attempt.

Mental disorders in the general population are associated with increased risk of suicidality, but less is known about the independent predictive ability of self-reported psychological symptoms. We followed 49,321 screened and interviewed Swedish conscripts through 36-year follow-up to test whether psychological symptoms predicted suicide and hospitalization for suicide attempts. There were 619 suicides and 1,230 suicide attempts during the follow-up period. After excluding subjects with any psychiatric diagnoses (n = 5,691, 12%) and controlling for other psychological symptoms, severe symptoms of anger, trouble falling asleep, and feeling down predicted suicide. Similarly anger, headaches, feeling down, and nervousness predicted suicide attempt. Self-reported psychological symptoms may have a predictive value beyond psychiatric diagnosis.

Sickness absence at a young age and later sickness absence, disability pension, death, unemployment and income in native Swedes and immigrants.

BACKGROUND: Sickness absence with cash benefits from the sickness insurance gives an opportunity to be relieved from work without losing financial security. There are, however, downsides to taking sickness absence. Periods of sickness absence, even short ones, can increase the risk for future spells of sickness absence and unemployment. The sickness period may in itself have a detrimental effect on health. The aim of the study was to investigate if there is an association between exposure to sickness absence at a young age and later sickness absence, disability pension, death, unemployment and income from work. METHODS: Our cohort consisted of all immigrants aged 21-25 years in Sweden in 1993 (N = 38 207) and a control group of native Swedes in the same age group (N = 225 977). We measured exposure to sickness absence in 1993 with a follow-up period of 15 years. We conducted separate analyses for men and women, and for immigrants and native Swedes. RESULTS: Exposure to ≥60 days of sickness absence in 1993 increased the risk of sickness absence [hazard ratio (HR) 1.6-11.4], unemployment (HR 1.1-1.2), disability pension (HR 1.2-5.3) and death (HR 1.2-3.5). The income from work, during the follow-up period, among individuals with spells of sick leave for ≥60 days in 1993 was around two-thirds of that of the working population who did not take sick leave. CONCLUSIONS: Individuals on sickness absence had an increased risk for work absence, death and lower future income.

Unemployment and coronary heart disease among middle-aged men in Sweden: 39 243 men followed for 8 years.

BACKGROUND: Although unemployment may be a stressful life event, its association with coronary heart disease (CHD) remains unclear. This study examines the association between unemployment and later hospitalisation due to CHD. METHODS: The study was based on a Swedish military conscription cohort of 18 to 20-year-old men from 1969/1970 (n=49 321) with information provided on health status and health behaviours. Information on unemployment in middle age was obtained from national registers. CHD information was obtained from hospital registers and the cause of death register. Cox proportional hazard analyses were run on the 39 243 individuals who were in paid employment in 1996 and 1997. RESULTS: It was found that ≥90 days of unemployment was associated with subsequent CHD during 8 years follow-up (crude HR=1.47, 95% CI 1.23 to 1.75). Controlling for known risk factors for CHD reduced the association but a significant association remained (HR=1.24, 95% CI 1.04 to 1.48); ≥90 days of unemployment was significantly associated with CHD during the first 4 years (HR adjusted for known risk factors=1.31, 95% CI 1.01 to 1.71). CONCLUSIONS: Unemployment was associated with increased risk of CHD after adjustment for confounders. We interpret the increased risk of CHD associated with unemployment as potentially the somatic result of a process started by stress.

Working conditions, serotonin transporter gene polymorphism (5-HTTLPR) and anxiety disorders: a prospective cohort study.

BACKGROUND: The etiology and pathology of anxiety disorders involve both genetic and environmental influences. Adverse working conditions may contribute to the development of anxiety. The serotonin transporter-linked polymorphic region (5-HTTLPR) has been implicated in stress sensitivity. Therefore, we investigated the potential interplay between 5-HTTLPR and job-related risk factors in the prediction of the occurrence of anxiety. METHODS: We conducted a prospective study using the first two waves of a Swedish population-based cohort. At Wave I, 1585 individuals without anxiety, depression or dysthymia who were active in the labor market during both waves were included. Information on job demands, skill discretion, decision authority and social climate was collected at Wave I. After a three year interval, the presence of anxiety disorders was determined at Wave II. All 1585 participants were genotyped for 5-HTTLPR. Both additive and multiplicative models were considered in examining the potential interaction between 5-HTTLPR and adverse working conditions on the development of anxiety. RESULTS: Anxiety was associated with high job demands but not with 5-HTTLPR. An interaction was observed between 5-HTTLPR and high job demands among females. Individuals with 5-HTTLPR high expression genotype (LL) developed anxiety disorders more frequently when exposed to high job demands compared to 'LS/SS' carriers. LIMITATIONS: A limited number of participants developed anxiety. CONCLUSIONS: High job demands predict the development of anxiety. The 5-HTT polymorphism has a moderating effect on the relationship between high job demands and anxiety among females.

Lack of adjustment latitude at work as a trigger of taking sick leave-a Swedish case-crossover study.

OBJECTIVES: Research has shown that individuals reporting a low level of adjustment latitude, defined as having few possibilities to temporarily adjust work demands to illness, have a higher risk of sick leave. To what extent lack of adjustment latitude influences the individual when making the decision to take sick leave is unknown. We hypothesize that ill individuals are more likely to take sick leave on days when they experience a lack of adjustment latitude at work than on days with access to adjustment latitude. METHODS: A case-crossover design was applied to 546 sick-leave spells, extracted from a cohort of 1 430 employees at six Swedish workplaces, with a 3-12 month follow-up of all new sick-leave spells. Exposure to lack of adjustment latitude on the first sick-leave day was compared with exposure during several types of control periods sampled from the previous two months for the same individual. RESULTS: Only 35% of the respondents reported variations in access to adjustment latitude, and 19% reported a constant lack of adjustment latitude during the two weeks prior to the sick-leave spell. Among those that did report variation, the risk of sick leave was lower on days with lack of adjustment latitude, than on days with access (Odds Ratio 0.36, 95% Confidence Interval 0.25-0.52). CONCLUSIONS: This is the first study to show the influence of adjustment latitude on the decision to take sick leave. Among those with variations in exposure, lack of adjustment latitude was a deterrent of sick leave, which is contrary to the à priori hypothesis. These results indicate that adjustment latitude may not only capture long-lasting effects of a flexible working environment, but also temporary possibilities to adjust work to being absent. Further studies are needed to disentangle the causal mechanisms of adjustment latitude on sick-leave.

Unemployment at a young age and later sickness absence, disability pension and death in native Swedes and immigrants.

BACKGROUND: Youth unemployment is an increasing problem for societies around the world. Research has revealed negative health effects of unemployment, and this longitudinal register-based cohort study examined the relationship between unemployment and later sickness absence, disability pension and death among youth in Sweden. METHOD: The study group of 199,623 individuals comprised all immigrants born between 1968 and 1972 who immigrated before 1990 (25,607) and a random sample of native Swedes in the same age-range (174,016). The baseline year was 1992, and the follow-up period was from 1993 to 2007. Subjects with unemployment benefit in 1990-91, disability pension in 1990-92, severe disorders leading to hospitalization in 1990-92 and subjects who emigrated during follow-up were excluded. RESULTS: Those who were unemployed in 1992 had elevated risk of ≥60 days of sickness absence (OR 1.02-1.49), disability pension (HR 1.08-1.62) and all except native Swedish women had elevated risk of death (HR 1.01-1.65) during follow-up compared with non-unemployed individuals. The risk of future sickness absence increased with the length of unemployment in 1992 (OR 1.06-1.54), and the risk of sickness absence increased over time. A larger part of the immigrant cohort was unemployed at baseline than native Swedes. Selection to unemployment by less healthy subjects may explain part of the association between unemployment and the studied outcomes. CONCLUSION: Unemployment at an early age may influence the future health of the individual. To a society it may lead to increased burdens on the welfare system and productivity loss for many years.

Demands, skill discretion, decision authority and social climate at work as determinants of major depression in a 3-year follow-up study.

PURPOSE: The psychosocial work environment may be a determinant of the development and course of depressive disorders, but the literature shows inconsistent findings. Thus, the aim of this study is to determine longitudinal effects of the job demands-control-support model (JDCSM) variables on the occurrence of major depression among working men and women from the general population. METHODS: The sample comprised 4,710 working women and men living in Stockholm, who answered the same questionnaire twice, 3 years apart, who were not depressed during the first wave and had the same job in both waves. The questionnaire included JDCSM variables (demands, skill discretion, decision authority and social climate) and other co-variables (income, education, occupational group, social support, help and small children at home, living with an adult and depressive symptoms at time 1; and negative life events at time 2). Multiple logistic regressions were run to calculate odds ratios of having major depression at time 2, after adjustment for other JDCSM variables and co-variables. RESULTS: Among women, inadequate work social climate was the only significant risk indicator for major depression. Surprisingly, among men, high job demands and low skill discretion appeared as protective factors against major depression. CONCLUSIONS: The results showed a strong relationship between inadequate social climate and major depression among women, while there were no certain effects for the remaining exposure variables. Among men, few cases of major depression hampered well-founded conclusions regarding our findings of low job demands and high skill discretion as related to major depression.

Work and health among immigrants and native Swedes 1990-2008: a register-based study on hospitalization for common potentially work-related disorders, disability pension and mortality.

BACKGROUND: There are many immigrants in the Swedish workforce, but knowledge of their general and work-related health is limited. The aim of this register-based study was to explore whether documented migrant residents in Sweden have a different health status regarding receipt of a disability pension, mortality and hospitalization for lung, heart, psychiatric, and musculoskeletal disorders compared with the native population, and if there were variations in relation to sex, geographical origin, position on the labor market, and time since first immigration. METHODS: This study included migrants to Sweden since 1960 who were 28-47 years old in 1990, and included 243 860 individuals. The comparison group comprised a random sample of 859 653 native Swedes. These cohorts were followed from 1991 to 2008 in national registers. The immigrants were divided into four groups based on geographic origin. Hazard ratios for men and women from different geographic origins and with different employment status were analyzed separately for the six outcomes, with adjustment for age, education level, and income. The influence of length of residence in Sweden was analyzed separately. RESULTS: Nordic immigrants had increased risks for all investigated outcomes while most other groups had equal or lower risks for those outcomes than the Swedes. The lowest HRs were found in the EU 15+ group (from western Europe, North America, Australia and New Zealand). All groups, except Nordic immigrants, had lower risk of mortality, but all had higher risk of disability pension receipt compared with native Swedes. Unemployed non-Nordic men displayed equal or lower HRs for most outcomes, except disability pension receipt, compared with unemployed Swedish men. A longer time since first immigration improved the health status of men, while women showed opposite results. CONCLUSIONS: Employment status and length of residence are important factors for health. The contradictory results of low mortality and high disability pension risks need more attention. There is great potential to increase the knowledge in this field in Sweden, because of the high quality registers.

Do job demands and job control affect problem-solving?

OBJECTIVE: The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. PARTICIPANTS: A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. METHODS: Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. RESULTS: Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. CONCLUSIONS: Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.

Low workload as a trigger of sick leave: results from a Swedish case-crossover study.

OBJECTIVES: To investigate if exposure to an unusually low workload when ill can trigger taking sick leave. METHODS: A case-crossover design was applied to 546 sick-leave spells obtained from a cohort of 1430 employees within six Swedish workplaces. New sick-leave spells were reported from the workplaces during 3 to 12 months follow-up. Exposure was assessed in structured participant interviews at sick leave. Case and control periods from the same individual were sampled according to the matched-pair and usual-frequency approaches. Results are presented as odds ratios with surrounding 95% confidence intervals. RESULTS: The odds ratio of sick leave on a day with an unusually low workload was 2.57 (confidence interval, 1.07-6.16). CONCLUSIONS: Becoming ill on a day with a lower workload than usual can trigger the decision to take sick leave.

Assessment of long-term and recent pesticide exposure among rural school children in Nicaragua.

OBJECTIVE: This study assessed pesticide exposure of children in rural Nicaragua in relation to parental pesticide use, from around conception to current school age, as part of an epidemiological evaluation of neurodevelopment effects. METHODS: We included 132 children whose parents were subsistence farmers or plantation workers, or had an agricultural history. As proxies for children's long-term exposures, we constructed cumulative parental pesticide-specific use indices for periods before and after the child's birth from data obtained using an icon-calendar-based questionnaire, of application hours (h) for plantation workers and subsistence farmers, and of kilograms of active ingredients (ai) only for subsistence farmers. Pesticide residues of TCPY, 3-PBA and 2,4-D were analysed in children's urine as indicators for current exposures. RESULTS: Life-time indices were highest for the organophosphates chlorpyrifos (median 114 h (min 2; max 1584), 19.2 kg ai (min 0.37; max 548)) and methamidophos (84 h (6; 1964), 12.2 kg ai (0.30; 780)). The P50 values of children's urinary residues were 3.7 µg/g creatinine for TCPY, 2.8 for 3-PBA and 0.9 for 2,4-D; TCPY values are comparable with those in other countries, but 3-PBA and 2,4-D are considerably higher. The maximum levels for all three pesticides are the highest reported for children. Residues increased on days after application, but most high residue levels were unrelated to parental pesticide applications. CONCLUSION: Urinary pesticide residues reveal high environmental exposure among children in rural Nicaragua. The quantitative parental pesticide use indices as proxies for children's exposures during different periods may be useful for the evaluation of developmental health effects.

Work-related psychosocial events as triggers of sick leave--results from a Swedish case-crossover study.

BACKGROUND: Although illness is an important cause of sick leave, it has also been suggested that non-medical risk factors may influence this association. If such factors impact on the period of decision making, they should be considered as triggers. Yet, there is no empirical support available.The aim was to investigate whether recent exposure to work-related psychosocial events can trigger the decision to report sick when ill. METHODS: A case-crossover design was applied to 546 sick-leave spells, extracted from a Swedish cohort of 1430 employees with a 3-12 month follow-up of new sick-leave spells. Exposure in a case period corresponding to an induction period of one or two days was compared with exposure during control periods sampled from workdays during a two-week period prior to sick leave for the same individual. This was done according to the matched-pair interval and the usual frequency approaches. Results are presented as odds ratios (OR) with 95% confidence intervals (CI). RESULTS: Most sick-leave spells happened in relation to acute, minor illnesses that substantially reduced work ability. The risk of taking sick leave was increased when individuals had recently been exposed to problems in their relationship with a superior (OR 3.63; CI 1.44-9.14) or colleagues (OR 4.68; CI 1.43-15.29). Individuals were also more inclined to report sick on days when they expected a very stressful work situation than on a day when they were not under such stress (OR 2.27; CI 1.40-3.70). CONCLUSIONS: Exposure to problems in workplace relationships or a stressful work situation seems to be able to trigger reporting sick. Psychosocial work-environmental factors appear to have a short-term effect on individuals when deciding to report sick.

Childhood socio-economic position and risk of coronary heart disease in middle age: a study of 49,321 male conscripts.

BACKGROUND: Poor social circumstances in childhood are associated with increased risk of coronary heart disease (CHD). In previous studies, social circumstances and risk factors in adulthood have been suggested to explain this association. In the present study, we included potential explanatory factors from childhood and adolescence. METHODS: We investigated the association between childhood socio-economic position (SEP) and CHD in middle age among 49,321 Swedish males, born during 1949-51, who were conscripted for military service at 18-20 years of age. Register-based data on childhood social circumstances, educational attainment and occupational class in adulthood were used in combination with information on cognitive ability, smoking, body mass index and body height in late adolescence obtained from a compulsory conscription examination. Incidence of CHD from 1991 to 2007 (between 40 and 58 years of age) was followed in national registers. RESULTS: We demonstrated an inverse association between childhood SEP and CHD in middle age: among men with the lowest childhood SEP the crude hazard ratio of CHD was 1.47 (95% CI = 1.30-1.67). Adjustment for crowded housing in childhood, body height, cognitive ability, smoking and BMI in late adolescence attenuated relative risks of CHD considerably. Additional adjustment for educational level had a further, although limited, attenuating effect on associations, but additional adjustment for occupational class had no such effect. CONCLUSIONS: Results showed that social, cognitive and behavioural factors evident prior to adulthood may be of greater importance in explaining the association between childhood SEP and CHD later in life than socio-economic indicators in adulthood.

Early-onset depression, anxiety, and risk of subsequent coronary heart disease: 37-year follow-up of 49,321 young Swedish men.

OBJECTIVES: The purpose of this study was to investigate the long-term cardiac effects of depression and anxiety assessed at a young age, when reverse causation is not feasible. BACKGROUND: Most prospective studies found a relatively strong association between depression and subsequent coronary heart disease (CHD). However, almost exclusively, only middle-age or older participants were examined, and subclinical atherosclerosis might contribute to the observed association. The prospective association between anxiety and CHD was less evident in previous studies and has been subjected to similar methodological concerns on the possibility for a reverse causation. METHODS: In a nationwide survey, 49,321 young Swedish men, 18 to 20 years of age, were medically examined for military service in 1969 and 1970. All the conscripts were seen by a psychologist for a structured interview. Conscripts reporting or presenting any psychiatric symptoms were seen by psychiatrists. Depression and anxiety was diagnosed according to International Classification of Diseases-8th Revision (ICD-8). Data on well-established CHD risk factors and potential confounders were also collected (i.e., anthropometrics, diabetes, blood pressure, smoking, alcohol consumption, physical activity, socioeconomic position, family history of CHD, and geographic area). Participants were followed for CHD and for acute myocardial infarction for 37 years. RESULTS: Multiadjusted hazard ratios associated with depression were 1.04 (95% confidence interval [CI]: 0.70 to 1.54), 1.03 (95% CI: 0.65 to 1.65), for CHD and for acute myocardial infarction, respectively. The corresponding multiadjusted hazard ratios for anxiety were 2.17 (95% CI: 1.28 to 3.67) and 2.51 (95% CI: 1.38 to 4.55). CONCLUSIONS: In men, aged 18 to 20 years, anxiety as diagnosed by experts according to ICD-8 criteria independently predicted subsequent CHD events. In contrast, we found no support for such an effect concerning early-onset depression in men.

Non-participation in the second wave of the PART study on mental disorder and its effects on risk estimates.

BACKGROUND: In epidemiological studies, analyses are needed to investigate the consequences of non-response. AIMS: To analyse the consequences of attrition in the second wave of the population-based PART study, which was performed three years after the first wave. METHODS: Potential determinants for non-participation obtained from population registers and the first wave were analyzed. The relationships between potential determinants and reduced well-being or depressive mood in the first wave questionnaire were investigated separately for participants and non-participants in the second wave. Samples of respondents to the second wave questionnaire with reduced or not reduced well-being were summoned for interview regarding determinants of distress and disorder. The occurrence of potential determinants was compared between participants and non-participants in both groups. RESULTS: Low income, low education, non-Nordic origin, not being married and previous psychiatric diagnosis were associated with lower participation rates. These variables were similarly related to depressive mood and low psychological well-being in the first wave among participants and non-participants in the second wave. Potential determinants were not or only weakly related to participation in the interview groups. CONCLUSION: Although the true prevalence of distress and disorder is underestimated, the true associations between potential determinants and the outcomes seem reasonably well reproduced.

Low level of adjustment latitude--a risk factor for sickness absence.

BACKGROUND: The prerequisite for obtaining sickness benefit is reduced work ability for medical reasons in combination with work demands which cannot be adjusted accordingly. The aim of this study was to investigate if low levels of adjustment latitude, defined as the possibility to temporarily adjust work demands in case of ill health, influence sickness absence. METHODS: A prospective cohort study of 1420 employees (47% participation, aged 19-68; 56% women) was conducted at six Swedish workplaces. Exposure to two general and nine specific types of adjustment latitude was ascertained at baseline. Outcome was defined as the first new employer-reported sick-leave spell during a follow-up of 3-12 months. Hazard ratios (HR) of sick leave, with 95% confidence intervals (CI), were estimated by Cox proportional hazards regression. RESULTS: The incidence of sickness absence was 2.85/1000 person-days. The self-reported reasons for sick leave were mainly minor complaints such as colds, influenzas and headaches. Employees lacking adjustment latitude had an adjusted HR of sickness absence of 1.51 (95% CI 1.08-2.11). Among specific adjustment latitude types, those not having the possibility to work from home generated an HR of 1.86 (95% CI 1.31-2.64). The effects of lack of adjustment latitude were similar for men and women but seemed to vary between different occupations. CONCLUSION: A low level of adjustment latitude at work is a risk factor for sickness absence.

Decreased kidney function of unknown cause in Nicaragua: a community-based survey.

BACKGROUND: End-stage kidney disease overwhelms health services in Central America. We determined prevalences of decreased kidney function in distinct populations in the most affected region of Nicaragua. STUDY DESIGN: Cross-sectional survey. SETTING & PARTICIPANTS: Total populations aged 20-60 years of 5 villages in Northwest Nicaragua: mining/subsistence farming (elevation, 100-300 m above sea level), banana/sugarcane (100-300 m), fishing (0-100 m), services (0-100 m), and coffee (200-675 m); 479 men and 617 women (83% response). PREDICTOR OR FACTOR: Village; participant sex, age, and occupation; conventional chronic kidney disease risk factors. OUTCOMES: Serum creatinine (SCr) values greater than laboratory reference range for sex, estimated glomerular filtration rate <60 mL/min/1.73 m(2), proteinuria stratified in the low (dipstick protein excretion, 30-300 mg/dL) and high (>300 mg/dL) range. RESULTS: Prevalences of abnormal SCr levels: 18% (of all men) and 5% (of all women); in the mining/subsistence farming village, 26% and 7%; banana/sugarcane, 22% and 6%; fishing, 13% and 4%; services, 0% and 1%; and coffee, 7% and 0%. Prevalences of estimated glomerular filtration rate <60 mL/min/1.73 m(2): 14% (of all men) and 3% (of all women); in the listed villages, 19% and 5%, 17% and 4%, 10% and 2%, 0% and 0%, and 7% and 0%, respectively. Proteinuria, predominantly in the low range, affected 14% and 11% of all men and women without marked differences between villages. By occupation, abnormal SCr levels occurred in 31% and 24% of male and female agricultural workers at 100-300 m above sea level, but not at higher altitudes, and also was high in male artisans (43%), construction workers (15%), and miners (14%). In logistic regression models, for the banana/sugarcane and mining/subsistence farming villages, high blood pressure and age were significant predictors of abnormal SCr levels in men, and for mining/subsistence farming, age in women. LIMITATIONS: Causality is not addressed. CONCLUSIONS: In some Nicaraguan villages and population segments, men in particular show a high prevalence of decreased kidney function of unknown origin, possibly environmental or occupational.

Silica exposure among male current smokers is associated with a high risk of developing ACPA-positive rheumatoid arthritis.

OBJECTIVE: To study the association between silica exposure, separately as well as combined with smoking, and the risk of developing rheumatoid arthritis (RA) with or without the presence of antibodies against citrullinated peptide antigens (ACPA). METHODS: This Swedish population based case-control study analysed 577 incident RA cases and 659 randomly selected controls, all men aged 18-70 years, included during May 1996 to May 2006. Self-reported silica exposure, defined as exposure to stone dust, rock drilling or stone crushing and cigarette smoking was registered. ACPA status among cases was analysed. RESULTS: Silica-exposed subjects were found to have a moderately increased risk of ACPA-positive RA (odds ratio (OR) adjusted for age and residency=1.67 (95% CI 1.13 to 2.48), but not of ACPA-negative RA (OR=0.98 (95% CI 0.57 to 1.66)), compared with subjects unexposed to silica. SUBJECTS: exposed to rock drilling were found to have a somewhat more markedly increased risk of ACPA-positive RA (OR=2.34 (95% CI 1.17 to 4.68)). A high risk of developing ACPA-positive RA was observed among silica-exposed current smokers (OR=7.36 (95% CI 3.31 to 16.38)), exceeding the risk expected from the separate effects of silica exposure and current smoking, indicating an interaction between these exposures (attributable proportion due to interaction=0.60 (95% CI 0.26 to 0.95)). CONCLUSION: Silica exposure combined with smoking among men is associated with an increased risk of developing ACPA-positive RA. These results suggest that different inhalation exposures may interact in the aetiology of ACPA-positive RA.

Early precursors and enabling skills of reading acquisition.

Research on early linguistic precursors and enabling skills of reading acquisition among young children is reviewed. Language development starts early in infancy when the child learns to categorize the speech sounds according to the pattern typical of the mother tongue. Equipped with these sound categories the child is ready to learn to segment words from the sound stream and to understand and to use words. The precise phonological representation of words will facilitate the important development of phonological awareness, a basic prerequisite for reading acquisition. This paper reviews some of my longitudinal research and training studies indicating the causal direction of the relation between phonological awareness and reading and includes some ongoing studies, where gender differences, socio-economic factors, dose-response-effects and motivational factors are explored. Preventive and remedial implications of the findings are pointed out. Finally, the complexity of the causal relationships between different aspects of early language development, including genetic influences and later reading is pointed out.

Components of the illness flexibility model as explanations of socioeconomic differences in sickness absence.

The authors studied the social gradient in sickness absence in relation to components of the illness flexibility model, which highlights conditions affecting whether people attend work when they are ill. The conditions studied were: adjustment latitude, attendance requirements at work, stimulating work, and health. The population sample was part of a panel originating in 1994 when 15,154 inhabitants of Stockholm County were randomly selected to receive a questionnaire covering, among other things, health and psychosocial conditions. New questionnaires were sent to the respondents in 1998 and 2002. This article analyzes the 2002 data, for 1,634 women and 1,063 men. These respondents had reported being employed or on leave of absence. In this sample, a social difference was found in sickness absence of 31 days or more per year. For manual workers, women had an odds ratio (OR) of 2.8 and men an OR of 3.4 for such absence compared with nonmanual workers of both sexes in high socioeconomic positions. All single potential confounders decreased these ORs. Adding all characteristics decreased the OR by 78 percent for women and 67 percent for men. The results indicate that the social gradient in sickness absence is due to differences in health and in working conditions when one is ill.