Jean-Marc Soulat

Shift Work and Metabolic Syndrome: Respective Impacts of Job Strain, Physical Activity, and Dietary Rhythms

The impact of shift work on cardiovascular disease (CVD) risk factors and metabolic syndrome are not yet completely understood. The objectives of this study were to evaluate the impact of shift work on metabolic syndrome according to two different definitions in a population of strictly rotating shift workers (3×8 h) compared to paired counterparts working only day hours, and to study whether shift work itself is a determinant of metabolic syndrome after taking into account a large panel of confusing factors. We conducted a cross‐sectional study comparing 98 strictly rotating shift workers to 100 regular day‐workers (all subjects had a long experience of their working rhythms) within the same petrochemical plant. Clinical, behavioral, occupational, and biological data were collected, and a detailed nutritional investigation was done. Shift and day workers were comparable in terms of major CVD factors, and both had a 10 yr Framingham risk scoring of 11%. Shift workers reported an increased job strain and higher total and at‐work physical activity. Alterations in metabolic parameters were evident with a rise in triglycerides, free fatty acids, and gamma glutamyl transpeptidase and lower HDL‐cholesterol. Multiple logistic regression analysis demonstrated that shift work was associated with occurrence of metabolic syndrome, as defined by the National Cholesterol Education Program‐ATPIII criteria, OR: 2.38 (1.13–4.98), but not using the more recent score from the International Diabetes Federation, which gives a major emphasis on abdominal obesity. Total energy intake and contributions of the major nutrients did not differ between the two groups, with the notable exception of saturated lipids (+10% in shift workers). Meal distribution was clearly different: energy intake was more fractionated within the day, with a lesser contribution of breakfast and lunch but with increased intakes during intermediate light meals, particularly in the afternoon and night. Multivariate analyses were performed to test for the influence of dietary rhythms on the development of an NCEP‐ATPIII metabolic syndrome. Dietary intakes at breakfast and during intermediate light meals appear to be “protective” against metabolic syndrome, while a high load at dinner favors its occurrence. A high intake at lunch is particularly deleterious to shift workers. However, in all tested models, shift work remained significantly associated with metabolic syndrome, after taking into account potential covariates like job strain, physical activity, quantitative dietary parameters, and meal distribution. A specific follow‐up of shift workers should be recommended to occupational physicians.

Predictive risk factors for chronic regional and multisite musculoskeletal pain: A 5-year prospective study in a working population

Summary Physical and psychological work‐related factors pertaining to the 5‐year incidence of multiple body sites musculoskeletal pain (MSP) may be gender specific. In particular, psychological factors seem to be predictive of onset of MSP, but only in women. Only the physical work factor (ie, forceful effort constraints) was an important robust predictor of multisite MSP, but only in men. ABSTRACT The role of psychosocial and physical factors in the development of musculoskeletal pain (MSP) has now been clearly demonstrated. However, it is unclear whether these factors contribute to specific regional MSP or to multisite pain. The main goal of this study was to assess the impact of work‐related factors according to gender on the development of regional and multisite MSP. A total of 12,591 subjects (65% men and 35% women) who were born in 1938, 1943, 1948, and 1953 and were participating in a French longitudinal prospective epidemiological survey (ESTEV) in 1990 to 1995 were eligible. Personal factors and work exposure were assessed by self‐administered questionnaires. Statistical associations between chronic MSP (regional body site or multisite), personal factors, and occupational factors were analyzed using logistic regression modeling. The incidence of regional MSP and multisite pain in 1995 were, respectively, 17% and 25.6%. For women, highly repetitive movements predicted neck/shoulder pain; posture and vibrations predicted arm and low back pain; and effort with tools predicted arm pain. For men, forceful effort and vibrations predicted neck/shoulder pain; posture and forceful effort predicted lower limb and low back pain; and forceful effort and effort with tools predicted arm pain. Physical constraints (ie, forceful effort or vibrations) were associated with multisite pain in both genders. Only for women, psychological factors were risk factors predictive of upper limb pain and in 3 or 4 painful anatomical sites. These results support the hypothesis that some physical and psychological work‐related factors are predictive of regional or multisite MSP but differ according to gender. Gender differences and risk factors for work‐related musculoskeletal pain should be also taken into account to more effectively target preventive measures.

Predictors of chronic shoulder pain after 5 years in a working population.

Summary Psychological work‐related factors, i.e., decision control, particularly the subject’s perception of their work as monotonous, was a more important predictor of chronic shoulder pain than job demand over a 5‐year follow‐up. ABSTRACT The role of psychosocial and physical factors in the development of shoulder pain has now been clearly demonstrated. However, only a few studies have analyzed these associations over time. The main goal of this study was to evaluate the predictive value of work‐related psychological and mechanical factors on chronic shoulder pain. A total of 12,714 subjects (65% men) born in 1938, 1943, 1948, and 1953 participating in a French prospective longitudinal epidemiological investigation in 1990 to 1995 Enquête Santé Travail Et Vieillissement (ESTEV) were included. Clinical examination was performed by 400 trained occupational physicians. Personal factors and work exposure were assessed by self‐administered questionnaires. Statistical associations between chronic shoulder pain and personal and occupational factors were analyzed using logistic regression modeling. A total of 1706 subjects experienced chronic shoulder pain in 1990, and 2089 experienced chronic shoulder pain in 1995. The incidence of chronic shoulder pain in 1995 was 11% (n = 1355). Forceful effort (odds ratio [OR] = 1.24 95% CI [1.05–1.44], awkward posture (OR = 1.34 95% CI [1.19–1.52]), decision latitude (OR = 1.19 [1.04 to 1.35]), and psychological demand (OR = 1.19 95% CI [1.06–1.32]) in 1990 were significantly associated with chronic shoulder pain in 1995, even after adjustment for personal factors and previous shoulder pain status. Awkward posture (OR = 1.43 [1.25 to 1.63]), psychological demand (OR = 1.24 [1.09 to 1.40]), and decision latitude (OR = 1.21 [1.04 to 1.41] work‐related factors in 1990 were associated with the development of chronic shoulder pain between 1990 and 1995. These results suggest that awkward posture, forceful effort, job demand, and decision control are predictors of chronic shoulder pain at work. Interventions designed to reduce the incidence of chronic shoulder pain must include both mechanical and psychological factors.

Blood pressure and working conditions in hospital nurses and nursing assistants. The ORSOSA study

BACKGROUND Healthcare workers often are unsatisfied with their working conditions despite declaring to like their jobs. Psychosocial constraints in the workplace have increased recently due to changes in work organization. These psychosocial constraints are linked to cardiovascular diseases. AIM To analyze the relationship between blood pressure levels and organizational occupational risk factors in female hospital workers, using a new questionnaire (the Nursing Work Index-Extended Organization [NWI-EO] questionnaire), which quantifies psychological and organizational work factors. METHODS The ORSOSA study is a national, multicentre, cohort study conducted in seven voluntary French university hospitals, including 214 work units with a total of 2307 nurses and 1530 nursing assistants. RESULTS Systolic and diastolic blood pressure appeared to be significantly associated with age (P<0.001) and excess weight (P<0.001). The difference between systolic blood pressure in day-shift and night-shift workers was 2.5mmHg (P<0.001). The NWI-EO dimension most strongly correlated with systolic and diastolic blood pressure was poor team relationships (P<0.01 for both). For a one-point difference in the NWI-EO stress score, systolic blood pressure was higher by a mean of 0.2mmHg. CONCLUSION These results suggest that poor relationships within teams are related to high blood pressure among hospital workers. They add to the evidence that working conditions should be considered and investigated further among other risk factors as a pathway to primary prevention of hypertension and cardiovascular diseases.

Thyroid Function Tests in Persons with Occupational Exposure to Fipronil

BACKGROUND Fipronil represents a chemical class of insecticides acting at the γ-aminobutyric acid receptor in pests. [corrected] Fipronil has been associated with a significant increase in the incidence of thyroid gland tumors concomitant with prolonged exposure to thyroid-stimulating hormone (TSH) in rats. An association between human TSH concentration and thyroid cancer has been also reported. The primary objective of this study was to test the hypothesis that chronic occupational fipronil exposure may be associated with abnormal thyroid function tests. METHODS In 2008, 159 workers of a factory manufacturing fipronil-containing veterinary drugs were assessed. Serum concentrations of TSH, total thyroxine, free thyroxine, fipronil, and fipronil sulfone were measured. RESULTS A positive and significant correlation was observed between serum fipronil or fipronil sulfone levels and duration of fipronil exposure. Serum fipronil sulfone concentration was negatively correlated with TSH concentration in fipronil-exposed workers, but with no significant increase in thyroid function test abnormalities. CONCLUSION This study did not show that chronic fipronil exposure was associated with an increase of thyroid function test abnormalities. But, despite the fact that fipronil exposure in rats has been associated with increased serum TSH, fipronil sulfone concentrations were negatively correlated with serum TSH concentrations in fipronil-exposed workers, raising the possibility that fipronil has a central inhibitory effect on TSH secretion in humans. Close occupational medical surveillance, therefore, appears to be required in factory workers manufacturing fipronil-containing veterinary drugs. Larger epidemiological studies as well as investigations on possible thyroid-disrupting mechanisms of fipronil are also required.

A French crop-exposure matrix for use in epidemiological studies on pesticides: PESTIMAT

Pesticide exposure assessment is a key methodological issue for epidemiological studies. The history of pesticide has proven difficult to obtain from individuals’ report because of the wide range of active ingredients (AIs). We developed a crop-exposure matrix, which intends to reconstitute parameters of pesticide exposure in France since 1950. PESTIMAT is composed of tables crossing crops and AIs by year and providing the following metrics: (1) probability (proportion of farmers having used the AIs); (2) frequency (number of treatment days); and (3) intensity (application rate of the AIs in kg/ha). Metrics were obtained by the combination of six sources: (i) registration information from the Agriculture Ministry; (ii) information from agricultural bodies on products marketed; (iii) agricultural recommendations by the Plant Health Protection body; (iv) treatment calendars provided by farmers; (v) data from associations of farmers; and (vi) data from the industry. To date, 529 AIs usable between 1950 and 2010 are included in PESTIMAT: 160 fungicides; 160 herbicides; and 209 insecticides. When combined with duration and determinants of intensity, the metrics in PESTIMAT will make it possible to calculate exposure scores and to search for dose–effect relationships, an important criterion for causality judgment in epidemiology.

Comment on: Systematic Review and Meta-Analysis of Occupational Outcomes After Bariatric Surgery

Dear Editor, We read with great interest the systematic review of Sharples and Cheruvu about occupational outcomes after bariatric surgery [1]. We congratulate the authors for their interesting work. The relationship between obesity and occupation raises a major public health issue. Obesity surgery is very powerful to improve quality of life. The authors pointed out the limited evidence in the literature regarding occupational outcomes following bariatric surgery. They demonstrated that bariatric surgery has a generally positive impact on occupational outcomes. This implies that surgery may have wider economic, social, and psychological benefits over and above its immediate health benefits [1]. We would like to add to authors’ conclusions, since their systematic review only identified ten studies, which compared occupational outcomes before and after surgery, between 2004 and 2015. We have identified 15 more studies [2–16], and we have chosen to include other surgical procedures (open surgeries, adjustable gastric banding, vertical banded gastroplasty) and older articles (from 1977 to 2016), because we cannot ignore the successive evolutions of bariatric surgery and the successive evolutions of work world. All studies published between 1977 and 2000 showed an increase in employment after surgery by 17–29% [2–5]. Furthermore, Peace et al. [6] observed that 36% of the operated patients had better occupational functioning, and Valley et al. [7] observed that 33% of their sample improved their educational or occupational status within the first postoperative year by taking courses, gaining employment, or advancing their occupational status. Crisp et al. [8] found that at 2 years after surgery, 30% of a nonworking sample had taken up a full-time job. Martin et al. [9] found increases in rates of employment in a publicly funded group: approximately 45% of those receiving public assistance could decrease their level of support. All these studies compared employment before and after surgery. Näslund and Agren [10] compared, at 1 year, operated patients to controls (those seeking bariatric surgery). OBES SURG (2017) 27:811–812 DOI 10.1007/s11695-016-2487-3