Ergonomic and individual risk factors for musculoskeletal pain in the ageing workforce.

BACKGROUND: The present study aimed to investigate the possible association between specific ergonomic and individual risk factors and musculoskeletal pain (MSP) in the back, shoulder, hip and knee region in workers aged 50-65y. METHODS: The study was a population based cross-sectional survey. The study population comprised citizens born between 1952-1966, living in Esbjerg municipality, Denmark, ultimo 2016 (n = 23,463). A questionnaire was sent electronically or by mail. The analysis included the working population only. A multivariate logistic regression was used for each of the following dependent variables; musculoskeletal pain for the past 3 months in the back, shoulder, hip and knee, where independent variables included ergonomic exposure, age, sex, body mass index (BMI) and leisure time physical activity (LTPA). RESULTS: The overall response rate was 58% and the data of individuals at work (n = 9,263) demonstrated several ergonomic exposures with increased odds for pain in specific regions. Exposure to back twisted or bend, squatting or lying on knees and to carrying or lifting were associated with musculoskeletal pain in the back, whereas exposure to back twisted or bend, arms above shoulder and repeated arm movement were associated with pain in the shoulder. Exposure to back twisted or bend, repeated arm movement, squatting or lying on knees and to carrying or lifting were associated with musculoskeletal pain in the hip. Important individual risk factors were also identified. Increasing age was significantly associated with increased pain in the hip but associated with less risk for pain in the back and shoulder. Males had higher odds for pain in the back and knee compared to females but lower odds for pain in the hip. BMI was particularly important for knee pain. The level of LTPA did not have an important association with MSP in any region. CONCLUSION: There is a significant positive association between ergonomic exposures and musculoskeletal pain, which were specific for the back, shoulder, hip and knee. In addition, the data demonstrated a differential association with age, sex and BMI. This needs to be considered for the treatment and classification of musculoskeletal pain and for future preventive initiatives.

Workability in the Ageing Workforce-A Population-Based Cross-Sectional Study.

BACKGROUND: The purpose of this study was to investigate the impact of age, musculoskeletal pain and ergonomic exposure on workability in the oldest group of workers. METHODS: The study was a population based cross-sectional survey. The study population comprised citizens born between 1952-1966, living in Esbjerg municipality ultimo 2016 (n = 23,463). A questionnaire was sent electronically or by mail. The analysis included the working population only. A stereotype logistic regression was used with the primary dependent variable being workability and independent variables included age, musculoskeletal pain, and ergonomic exposure. RESULTS: The response rate was 58% and the data demonstrated a significant negative association between age and workability. With excellent workability as a reference, the odds for poor workability increased by 97% being 60+ y compared to 50-55 y. Both moderate intensity and severe musculoskeletal pain in the back, shoulder and knee/hip all showed significantly higher odds for poor workability. Ergonomic exposures, such as standing/walking, working with back bent or twisted and carrying or lifting had a significant negative impact on workability. CONCLUSION: Age, musculoskeletal pain and ergonomic exposures showed a significant negative impact on workability in the oldest group of workers and should be targeted with preventive initiatives.

Pyromellitic dianhydride (PMDA) may cause occupational asthma.

INTRODUCTION: Anhydrides are widely used as cross-linking agents in epoxy resins and alkyd production, for example, as coatings and adhesives in plastic products. Sensitisation to several anhydrides is known to cause occupational asthma. There are indications that the lesser known pyromellitic dianhydride (PMDA) can cause irritative respiratory symptoms and possibly asthma. We report three cases of workers from a plastic foil manufacturing plant, who developed asthma when exposed to PMDA during specific inhalation challenge (SIC). METHODS: SIC was performed over 2 days according to recommendations of European Respiratory Society. Lactose powder was used in control challenges and a mixture of 10% PMDA and 90% lactose powder in active challenges. RESULTS: All cases experienced a delayed decrease in forced expiratory flow in 1 s (FEV1) 4-12 hours after active challenge. FEV1 decreased by 19%, 15% and 16%, respectively. After 21 hours, FEV1 decreased by 24% in one worker. DISCUSSION: Respiratory symptoms after working hours may represent delayed work-related asthma. During SIC, the three patients developed lower respiratory symptoms and a delayed decrease in FEV1 which suggest sensitisation. The mechanism of anhydride-related asthma is not well understood. Anhydrides are known irritants and hence an irritative response cannot be excluded. The company improved ventilation and enforced the use of respiratory protection equipment, and finally phased out PMDA. Occupational workplace risk identification may help to identify exposures. SIC can contribute to improving working conditions, by identifying and confirming asthmogens in the environment.

Determinants of persistent asthma in young adults.

Objective: The aim of the study was to evaluate determinants for the prognosis of asthma in a population-based cohort of young adults. Design: The study was a nine-year clinical follow up of 239 asthmatic subjects from an enriched population-based sample of 1,191 young adults, aged 20-44 years, who participated in an interviewer-administered questionnaire and clinical examination at baseline in 2003-2006. From the interview, an asthma score was generated as the simple sum of affirmative answers to five main asthma-like symptoms in order to analyse symptoms of asthma as a continuum. The clinical examination comprised spirometry, bronchial challenge or bronchodilation, and skin prick test. Results: Among the 239 individuals with asthma at baseline 164 (69%) had persistent asthma at follow up, while 68 (28%) achieved remission of asthma and seven (3%) were diagnosed with COPD solely. Determinants for persistent asthma were use of medication for breathing within the last 12 months: Short-acting beta-adrenoceptor agonists (SABA) only (OR 3.39; 95%CI: 1.47-7.82) and inhaled corticosteroids (ICS) and/or long-acting beta-adrenoceptor agonists (LABA) (8.95; 3.87-20.69). Stratified by age of onset determinants for persistence in individuals with early-onset asthma (age less than 16 years) were FEV1 below predicted (7.12; 1.61-31.50), asthma score at baseline (2.06; 1.15-3.68) and use of ICS and/or LABA within 12 months (9.87; 1.95-49.98). In individuals with late-onset asthma the determinant was use of ICS and/or LABA within 12 months (6.84; 2.09-22.37). Conclusions: Pulmonary function below predicted, severity of disease expressed by asthma score and use of ICS and/or LABA were all determinants for persistent early-onset asthma, whereas only use of ICS and/or LABA was a determinant in late-onset asthma. A high asthma score indicated insufficient disease control in a substantial proportion of these young adults.

Risk factors for incident asthma and COPD in a cohort of young adults.

INTRODUCTION: The aim of the study was to describe potential shared risk factors for incident asthma and COPD in a population-based, 9-year follow-up study. METHODS: From a cohort of 1191 individuals, aged 20-44, who participated in baseline survey including spirometry, bronchial challenge, and skin prick test (SPT) 742 subjects (62%) were reexamined at follow-up in 2012-2014. RESULTS: A total of 27 incident cases of asthma and 22 cases of COPD were identified at follow-up corresponding to an incidence rate of 5.8 (95% CI 3.9-8.4) and 3.5 (2.2-5.3) per 1000 person years, respectively. Among the identified COPD cases a total of 12 were Asthma-COPD Overlap Syndrome (ACOS). Atopy defined by positive SPT was a risk factor for asthma in males (OR 7.54; 95% CI 1.24-45.90), whereas risk factors in females were nasal allergy (3.81; 1.20-12.11), FEV1 <100% predicted (3.96; 1.07-14.62) and parental asthma (3.06; 1.00-9.40). Risk factors for COPD in males were bronchial hyperresponsiveness (23.13; 1.41-380.50) and FEV1 <100% predicted (all male cases had FEV1 <100% predicted) and in females current smoking (3.34; 1.16-9.59) and asthma at baseline (5.21; 1.48-18.34). CONCLUSIONS: No shared risk factors for incident asthma and COPD were found. Despite low power when stratifying by sex risk factors for incident asthma and COPD emphasize considerable gender differences.

Genetic polymorphisms in antioxidative enzymes are associated to forced expiratory volume in 1 s (FEV1) in smokers independently of asthma.

INTRODUCTION: In this study, we hypothesised that the genotypes coding for low antioxidative enzyme activity are associated with asthma and reduced lung function. METHODS: Using the European Community Respiratory Health Survey protocol, we enlisted 1091 Danish subjects in this cross-sectional study. Asthma phenotypes were defined as asthma symptoms in combination with steroid usage, bronchial hyperresponsiveness and atopy. These phenotypes and lung function were analysed with respect to glutathione peroxidase, GPX1 (Pro198Leu, rs1050450), manganese superoxide dismutase, SOD2 (Ala16Val, rs4880) and three glutathione S-transferases; GSTP1 (Ile105Val, rs1695), GSTT1 (gene copy number) and GSTM1 (gene copy number). RESULTS: We found no associations between these genotypes and the asthma phenotypes. For the 201 subjects identified as current smokers and recruited via random sampling, an association was seen between increasing number of genotypes coding for high antioxidative enzyme activity (GPX1 Pro/Pro, SOD2 Val/Val, GSTP1 Ile/Ile, GSTT1 two copies, GSTM1 two copies) and forced expiratory volume in 1 s (FEV1%) predicted. The increase in FEV1% predicted was 2.0% (95% confidence interval 0.3-3.8) per genotype. There was no identified significance for the inverse association between FEV1% predicted and number of genotypes coding for low antioxidative enzyme activity. CONCLUSION: The present study does not support the hypothesis that asthma is associated with genotypes of these major antioxidative enzymes. However, we speculate that since we see an impact of these genotypes on lung function in young adult smokers, polymorphisms in antioxidative enzymes may contribute to the range of susceptibility of smokers have to Chronic obstructive lung disease.

Intake of alcohol and risk of adult-onset asthma.

AIM: To examine the association between intake of alcohol and risk of adult-onset asthma. METHODS: Using data from two multidisciplinary questionnaire surveys we prospectively studied 19,349 twins, 12-41 years of age, from the nationwide Danish Twin Registry. RESULTS: The eight-year incidence of asthma was 4.3%. After adjustment for sex, age, BMI, physical activity, educational level and smoking, the risk of new-onset asthma was significantly related to overall alcohol intake in a U-shaped manner with the lowest risk observed in the group with a moderate weekly intake of alcohol (1-6 units/week), p = 0.006. The highest risk of asthma was observed in rare/never drinkers (<1 unit/month), OR = 1.59 (1.25-2.02), p = 0.000, whereas the risk of asthma in heavy daily drinkers (≥4 units/day) was also increased, however not statistically significant, OR = 1.13 (0.54-2.36), p = 0.747. The risk of new-onset asthma was lower for subjects with wine preference (3.3%) compared with beer preference (4.3%) or no preference (4.4%). After multivariable adjustment, wine preference was inversely related to incident asthma compared with beer preference. However, this finding was not statistically significant, OR = 0.87 (0.51-1.46), p = 0.590. CONCLUSION: Alcohol intake is associated with new-onset asthma in adults with a U-shaped association between amount of alcohol intake and the risk of asthma.

Increase in the heritability of asthma from 1994 to 2003 among adolescent twins.

BACKGROUND: Over the past decades the prevalence of asthma has increased in most parts of the world, and widespread changes in lifestyle and environment have been postulated as the primary cause for this. We examined whether the extent to which genetic and environmental factors influence susceptibility to asthma has changed between 1994 and 2003. METHODS: Two different cohorts of twins (n = 3393 and n = 2813 pairs), both 12-20 years of age, from the Danish Twin Registry, participated in questionnaire studies nine years apart. Prevalence of asthma and resemblance between twins for asthma was compared between the two cohorts. RESULTS: The prevalence of asthma increased from 7.1% in 1994 to 10.8% in 2003, p < 0.001. The change was significant both in males (7.7 vs. 12.4%, p < 0.001); and females (6.6 vs. 9.2%, p < 0.001). The best-fitting model, which included additive genetic and non-shared environmental effects, showed that the heritability of asthma increased significantly from 79% in 1994 to 91% in 2003, p = 0.005. CONCLUSIONS: This result could indicate that environmental changes over the past years have increased the expression of genes and thus have lead to a higher heritability in the succeeding cohort. This is consistent with the hypothesis that changes in the environment, particular in childhood, are the cause of the increase in the prevalence of asthma over the past decades.

Regular use of non-steroidal anti-inflammatory drugs increases the risk of adult-onset asthma: a population-based follow-up study.

BACKGROUND: Little is known about the relation between regular use of non-steroidal anti-inflammatory drugs (NSAIDs) and the risk of asthma at the population level. The aim of this study was to examine a possible association between intake of NSAIDs and risk of adult-onset asthma. METHODS: Using data from two multidisciplinary postal questionnaire surveys concerning health and lifestyle, we prospectively studied 19 349 adult twins enrolled in the nationwide Danish Twin Registry. RESULTS: We found a higher prevalence of new-onset asthma in subjects who used NSAIDs (other than aspirin) regularly compared with non-users (7.7% vs 4.3%), OR = 1.87 (1.25-2.81), P = 0.002. The result remained significant after adjusting for sex, age, smoking, BMI, hay fever, eczema and intake of medications other than NSAIDs, OR = 1.90 (1.26-2.85), P = 0.002. CONCLUSIONS: Regular use of NSAIDs other than aspirin may be a risk factor for adult-onset asthma. This observation must be accommodated in explanations of the relationship between use of analgesics and risk of asthma.

Genetic and environmental contributions to hay fever among young adult twins.

BACKGROUND: The susceptibility to develop hay fever is putatively the result both of genetic and environmental causes. We estimated the significance and magnitude of genetic and environmental contributions to hay fever among young adult twins. METHODS: From the birth cohorts 1953-82 of The Danish Twin Registry 11,750 twin pairs were identified through a nationwide questionnaire survey. Subjects were regarded hay fever cases when responding affirmatively to the question 'Do you have, or have you ever had hay fever?' Latent factor models of genetic and environmental effects were fitted to the observed data using maximum likelihood methods. RESULTS: The overall cumulative prevalence of hay fever was 12.6%. Identical twins were significantly more likely to be concordant for hay fever than were fraternal twins (P<0.001). Additive genetic effects accounted for 71% and non-shared environmental effects accounted for 29% of the individual susceptibility to hay fever. The same genes contributed to the susceptibility to hay fever both in males and in females. In families with asthma, the susceptibility to develop hay fever was, in addition to genes, to a great extent ascribable to family environment, whereas the aetiology of 'sporadic' hay fever was mainly genetic. CONCLUSIONS: The susceptibility to develop hay fever is attributable to major genetic influences. However, effects of family environment and upbringing are also of importance in families where asthma is present. These results indicate that different sub-forms of hay fever may have different aetiologies.

[The significance of conditions when growing up on the prevalence of atopy in adult Danes]. / Opvaekstforholds betydning for atopiske lidelser hos voksne danskere.

INTRODUCTION: The prevalence of atopy in adults depends on both hereditary and environmental factors. The influence of environmental factors is explained in the "hygiene hypothesis" by maturational changes in the immunological system in response to limited microbiologic challenges in early life. Several studies have indicated protective effects of varying conditions in early life, e.g., living on a farm and in particular with livestock. This study analyses this problem in a Danish population. METHODS: This cross-sectional study used the European Community Respiratory Health Survey (ECRHS) protocol. A screening questionnaire concerning asthma, asthma-related symptoms and nasal allergy supplemented by questions about environmental factors was distributed to 10,000 randomly chosen individuals, 20 to 44 years of age, in five Danish counties. RESULTS: The questionnaire was answered by 7,271 individuals (72.7%). The prevalence of asthma and nasal allergy in adults was independent of growing up in the city or the country, but a significant inverse association was seen when growing up in the country in proximity to livestock. This effect remained after controlling for different hereditary and environmental factors. DISCUSSION: The results of this population-based study are consistent with the results from similar international studies. This study demonstrates that growing up in the country with contact with livestock protects against the development of asthma and nasal allergy in adults.