healthmedicinet

This study examined the prevalence of anxiety symptoms in Korean female manufacturing
workers to determine the association of anxiety symptoms with occupational stress
that is thought to result from the psychosocial work environment. Our results reveal
that the occurrence of anxiety symptoms is significantly related to the presence of
occupational stress stemming from the psychosocial work environment.

The prevalence of anxiety symptoms among the present population was 15.2 %. In a study
on the association between aircraft noise exposure and anxiety symptoms in the general
Korean population aged between 30 and 70 years (mean age 60.7), 19.2 % of those in
the non-noise exposure group had anxiety symptoms (a score of ?22 for the Korean version
of the BAI) 28]. The prevalence of anxiety symptoms in the previous study is higher than that reported
in the present study among female workers aged between 10 and 39 years. In addition,
a study that evaluated the anxiety symptoms of Korean male office workers using the
Depression Anxiety Stress Scale found 19.5 % of them to have a moderate to severe
level of anxiety symptoms 20]. In a study from the Netherlands on 45 Dutch office workers, the prevalence of subclinical
anxiety among the women was reported as 10 % using the Hospital Anxiety and Depression
Scale 18]. In China, Gao et al. 19] found the prevalence of anxiety symptoms among Chinese nurses to be 43.4 % using
the Self-Rating Anxiety Scale. However, the results of these studies should be interpreted
with caution since each study evaluated anxiety symptoms using different tools.

The prevalence of anxiety symptoms among female manufacturing workers of this study
may not be seriously high. However, because two recent studies have suggested that
the presence of anxiety symptoms is significantly related to the prevalence of suicidal
ideation and suicide attempts 29], 30]. With suicide being the highest cause of death among Korean women aged between 10
and 39 years old 31], anxiety symptoms potentially can be important health problem among Korean female
workers, especially 10–39 years old. Henceforth, study and management of anxiety symptoms
might be needed among Korean female workers of diverse occupation, especially 10–39
years old.

The level of occupational stress stemming from the psychosocial work environment among
the female manufacturing workers in the present study is lower than the average level
previously reported for Korean female workers. The total KOSS-SF score as well as
the scores for job demand, job insecurity, organizational system, lack of reward,
and occupational climate were lower than the average score previously reported for
Korean female workers. However, the average scores for insufficient job control and
interpersonal conflict were higher than the average score previously reported for
Korean female workers. Among the total population, 55 % showed scores that fell into
the high-risk category(the fourth quartile of the KOSS-SF reference values) for insufficient
job control, which was also found to be the greatest cause of occupational stress.
Because the work-related responsibilities of these female workers are relatively simple
and the majority (93.6 %) is shift workers, it might be difficult for them to adjust
their workload or work schedule, thus creating high levels of occupational stress.

We found a significant association between anxiety symptoms with the total KOSS-SF
score and all KOSS-SF subscales besides insufficient job control, even after adjustment
for general characteristics and sleep quality. In a study by Park et al. 20] on Korean male office workers, a significant association was observed between anxiety
symptoms with the total KOSS-SF score and all KOSS-SF subscales besides insufficient
job control and job insecurity, a finding that is similar to the results of the present
study. However, the observation of a significant association between job insecurity
and anxiety symptoms in the present study was lacking in the study of Park et al.
20]. In a longitudinal study by Plaisier et al. 32], no significant association between job security and incidence of anxiety disorders
in men was found; however, in women, job security had a protective effect against
the later incidence of anxiety disorders. Therefore, sex-specific differences might
explain the discrepancies noted between these studies.

In this cross-sectional study, a relatively high OR was seen in the high-risk groups
for the subscales job demand (OR?=?3.19, 95 % CI?=?2.27–4.49), job insecurity (OR?=?4.52,
95 % CI?=?2.86–7.13), and occupational climate (OR?=?4.52, 95 % CI?=?2.90–7.04). In
two longitudinal studies, job demand was found to be significantly associated with
GAD or anxiety symptoms among female workers 17], 33]. Also job insecurity was found to be significantly associated with anxiety disorders
of female workers in a longitudinal study 32]. However few studies have investigated this relationship in longitudinal study design
among Korean female workers. Factors related to stress resulting from the occupational
climate such as an authoritative and hierarchical workplace, irrational communication,
and the uncomfortable atmosphere of company dinners, all of which are commonplace
in South Korea, is evaluated in the section of occupational climate. In the cross-sectional
study Among Korean male office workers, the occupational climate was found to be significantly
associated with anxiety symptoms 20]. However, few studies have attempted to investigate the possible association between
the very hierarchal workplace climate in South Korea and anxiety, especially among
Korean female workers. Accordingly, longitudinal study which investigate the relationship
between anxiety and job demand, job insecurity, occupational climate among Korean
female workers is needed.

The level of occupational stress caused by insufficient job control for subjects of
the present study was higher than the average score previously reported for Korean
female workers. Even though 55 % of these workers fell into the high-risk group (the
fourth quartile of the KOSS-SF reference values), there was no significant association
with anxiety symptoms. In the longitudinal study of Andrea et al. 33], decision latitude was not significantly associated with the future incidence of
subclinical anxiety symptoms. In addition, in other two longitudinal studies, decision
latitude was not significantly related with the occurrence of generalized anxiety
disorder in women 17] or with the occurrence of anxiety disorders 32]. The results of our study correspond with those of previous longitudinal studies.

In a cross-sectional study of Korean male office workers and in a cross-sectional
study of Italian radiologists, relational conflict among coworkers or superiors was
significantly associated with anxiety symptoms 20], 34]. In our study, interpersonal conflict displayed a significant association with anxiety
symptoms, confirming these previous results. However, in the longitudinal study by
Andrea et al. 33], conflict with coworkers or superiors was not significantly related with the future
incidence of subclinical anxiety symptoms; these results differed from those of this
study and another cross-sectional study 33].

For the Korean male office workers, there was a significant association reported between
the organizational system and anxiety disorders 20], and similar results were found in the female manufacturing workers of our study.
For the Korean male office workers and Italian radiologists from the two previous
studies mentioned above, a significant association between lack of reward and anxiety
symptoms was also reported 20], 34]; similar results were confirmed in the present study.

Aside from occupational stress, poor sleep quality was significantly associated with
anxiety symptoms in the multivariate logistic regression analysis. Sleep quality was
poor for 60.6 % of our subjects, and the majority (93.5 %) of our subjects were shift
workers. The association between shift work and sleep disturbance is well known 35]. Therefore, it is of concern that the ratio of workers with poor sleep quality is
relatively high. In previous studies, insomnia was associated with clinically significant
anxiety or anxiety disorders and was significantly associated with the future incidence
of anxiety disorders 36]–40]. Likewise, in our study, those with a poor quality of sleep were significantly more
likely to have anxiety symptoms than those who did not have poor quality of sleep.
Therefore, our results are similar to those of previous studies.

Our study has the following limitations. First, a survey was used to estimate the
prevalence of anxiety symptoms as opposed to the use of diagnostic criteria to clinically
diagnose these anxiety disorders. Second, the temporal relationship between anxiety
symptoms and occupational stress caused by the psychosocial work environment cannot
be established from the present study. Thus, future longitudinal studies are needed
that employ diagnostic criteria to define anxiety disorders as well as determine whether
a temporal relationship exists. Third, the use of a self-reported questionnaire can
lead to biases based on the individual subjectivity of the responders. Fourth, we
did not investigate whether other individual and/or familial factors are associated
with anxiety symptoms 41]. Finally, the limited age range limits the generalizability of our results to the
general Korean female workers.

Despite these limitations, this study is important because it confirms the significant
association between occupational stress and anxiety symptoms as well as draws attention
to this issue that affects Korean female manufacturing workers, especially 19–35 years
old. Large study population is also strong point of this study. Anxiety disorders
are the most common mental disorder among Korean women, with an increasing prevalence.
Considering the lack of research on the association of occupational stress with anxiety
symptoms or anxiety disorders among Korean female workers, future studies are needed
on subjects from a diverse range of occupations and age groups. Furthermore, there
might be a need for intervention programs 42]–44] that appropriately manage the psychosocial work environment and factors associated
with anxiety symptoms and anxiety disorders, especially among young female manufacturing
workers.