Objectives The aim of this review was to assess the risk of cardiovascular disease (CVD) events associated with shift work and determine if there is a dose-response relationship in this association. ...Method Electronic databases (PubMed, Scopus, and Web of Science) were searched for cohort or case-control control study designs in any population, reporting exposure to shift work as the main contributing factor to estimate CVD risk. For each study, adjusted relative risk (RR) ratios and 95% confidence intervals (CI) were extracted, and used to calculate the pooled RR using random-effect models. Meta-regression analysis was conducted to explore potential heterogeneity sources. Potential non-linear dose-response relationships were examined using fractional polynomial models. Results We included 21 studies with a total of 173 010 unique participants. The majority of the studies were ranked low-to-moderate risk of bias. The risk of any CVD event was 17% higher among shift workers than day workers. The risk of coronary heart disease (CHD) morbidity was 26% higher (1.26, 95% CI 1.10-1.43, I^2= 48.0%). Sub-group analysis showed an almost 20% higher risk of CVD and CHD mortality among shift workers than those who did not work shifts (1.22, 95% CI 1.09-1.37, I^2= 0% and 1.18, 95% CI 1.06-1.32 I^2=0%; respectively). After the first five years of shift work, there was a 7.1% increase in risk of CVD events for every additional five years of exposure (95% CI 1.05-1.10). Heterogeneity of the pooled effect size (ES) estimates was high (I^2=67%), and meta-regression analysis showed that sample size explained 7.7% of this. Conclusions The association between shift work and CVD risk is non-linear and seems to appear only after the first five years of exposure. As shift work remains crucial for meeting production and service demands across many industries, policies and initiatives are needed to reduce shift workers' CVD risk.
Shift work is characterized by employees working outside the standard hours of 7:00 am to 6:00 pm. Because shift work includes night work, the normal sleep-wake cycle (circadian rhythm) is disrupted, ...with potential consequences for shift workers' physical and mental health.
To assess the pooled effects of shift work on mental health and to evaluate whether these differ in men and women.
We searched PubMed, Scopus, and Web of Science databases for peer-reviewed or government reports published up to August 2018
To be included, studies had to be longitudinal or case-control studies of shift work exposure associated with adverse mental health outcomes. For subanalyses, we grouped these outcomes as anxiety symptoms, depressive symptoms, or general poor mental health symptoms.
We followed the Meta-Analysis of Observational Studies in Epidemiology Group guidelines. We extracted adjusted risk estimates for each study to calculate pooled effect sizes (ESs) using random effect models and metaregression analysis to explore sources of heterogeneity.
We included 7 longitudinal studies, with 28 431 unique participants. Shift work was associated with increased overall risk of adverse mental health outcomes combined (ES = 1.28; 95% confidence interval CI = 1.02, 1.62;
= 70.6%) and specifically for depressive symptoms (ES = 1.33; 95% CI = 1.02, 1.74;
= 31.5%). Gender differences explained more than 90% of heterogeneity, with female shift workers more likely to experience depressive symptoms than female non-shift workers (odds ratio = 1.73; 95% CI = 1.39, 2.14).
To our knowledge, this is the first meta-analysis to investigate the pooled effects of shift work on the risk of poor mental health, including subanalyses by type of poor mental health and gender. Shift workers, particularly women, are at increased risk for poor mental health, particularly depressive symptoms.
Depression accounts for 4.3% of the global burden of disease and incidence, with mental disorders worldwide predicted to cost US $16.3 million by 2030. With 1 in 5 people in the United States and Europe doing shift work, and the increased risk of poor mental health among shift workers, shift work industries are a priority context for reducing this burden. Workplace health promotion programs and policies are needed to minimize shift workers' risk of poor mental health.
There is rapidly-emerging evidence on the harmful health effects of sedentary behaviors. The aim of this paper was to quantify time in sedentary behaviors and document socio-demographic variations in ...different life domains among adults.
A population-based survey was carried out in 2012 through face-to-face interviews with Brazilian adults aged 20+ years (N = 2,927). Information about time spent sedentary in a typical weekday was collected for five different domains (workplace, commuting, school/university, watching TV, and computer use at home). Descriptive and bivariate analyses examined variations in overall and domain-specific sedentary time by gender, age, educational attainment and socioeconomic position.
On average, participants reported spending 5.8 (SD 4.5) hours per day sitting. The median value was 4.5 (interquartile range: 2.5-8) hours. Men, younger adults, those with higher schooling and from the wealthiest socioeconomic groups had higher overall sedentary scores. TV time was higher in women, older adults and among those with low schooling and socioeconomic position. Sedentary time in transport was higher in men, younger adults, and participants with high schooling and high socioeconomic position. Computer use at home was more frequent among young adults and those from high socioeconomic groups. Sitting at work was higher in those with higher schooling and from the wealthiest socioeconomic groups. Sedentary behavior at school was related inversely to age and directly to schooling.
Patterns of sedentary behavior are different by life domains. Initiatives to reduce prolonged sitting among Brazilian adults will be required on multiple levels for different life domains.
There is little long-term causal evidence on the effect of physical activity on health-related quality of life. This study aimed to examine the associations between longitudinal patterns of physical ...activity over 15 years and health-related quality of life in both the physical and mental health domains, in a cohort of middle-aged Australian women.
We used data collected at 3-year intervals (1998 to 2019) from 11,336 participants in the Australian Longitudinal Study on Women's Health (ALSWH) (1946 to 1951 birth cohort). Primary outcomes were the physical (PCS) and mental health component summary (MCS) scores (range from 0 to 100; higher scores indicate higher perceived physical/mental health) from the SF-36 in 2019 (when women aged 68 to 73 years). Using target trial emulation to imitate a randomized controlled trial (RCT), we tested 2 interventions: (1) meeting the World Health Organization (WHO) physical activity guidelines consistently throughout the 15-year "exposure period" (2001 to 2016; when women aged 50-55 to 65-70 years; physical activity assessed every 3 years); and (2) not meeting the guidelines at the beginning of the exposure period but starting to first meet the guidelines at age 55, 60, or 65; against the control of not meeting the guidelines throughout the exposure period. Analysis controlled for confounding using marginal structural models which were adjusted for sociodemographic and health variables and conditions. Consistent adherence to guidelines during the exposure period (PCS: 46.93 99.5% confidence interval CI: 46.32, 47.54) and first starting to meet the guidelines at age 55 (PCS: 46.96 99.5% CI: 45.53, 48.40) were associated with three-point higher PCS (mean score difference: 3.0 99.5% CI: 1.8, 4.1 and 3.0 99.5% CI:1.2, 4.8) than consistent non-adherence (PCS: 43.90 99.5% CI: 42.79, 45.01). We found a similar pattern for most SF-36 subscales but no significant effects of the interventions on MCS. The main limitations of the study were that it may not account for all underlying health conditions and/or other unmeasured or insufficiently measured confounders, the use of self-reported physical activity and that findings may not be generalizable to all mid-age women.
Results from the emulated RCT suggest women should be active throughout mid-age, ideally increasing activity levels to meet the guidelines by age 55, to gain the most benefits for physical health in later life.
Evidence of prospective associations between participation in sports and recreational activities (SRAs) and health outcomes at the population level is scarce. We investigated the associations between ...participation in SRAs and 6‐year incidence of hypertension, diabetes, and obesity in a cohort of mid‐age Australian adults. We analyzed data from the HABITAT study (n = 8784), a cohort of adults aged 40+ years living in Brisbane, Australia. Mail surveys in 2007, 2009, 2011, and 2013 were used to collect data on participation in 11 SRAs in the past 12 months, as well as self‐reported hypertension, diabetes, height, and weight. Obesity was defined as BMI ≥ 30.0 kg/m2. Logistic generalized estimating equation models with a 2‐year lag were used. Participation in SRAs in 2007, 2009, and 2011 was matched with outcomes measured in 2009, 2011, and 2013. From 2007 to 2013, the cumulative incidence of hypertension, diabetes, and obesity was 14.9%, 3.2%, and 11%, respectively. Running, tennis, team sports, exercise classes, and resistance training were associated with reduced odds of hypertension. Running, cycling, resistance training, and yoga/tai chi were associated with reduced odds of diabetes. Cycling, tennis, home‐based exercises, resistance training, and yoga/tai chi were associated with lower odds of obesity. Participation in SRAs was associated with lower incidence of hypertension, diabetes, and obesity in mid‐age adults over six years. These findings support current efforts to promote wider and continuing participation in SRAs at this life stage.
Abstract
Purpose
The aim was to use accelerometer data to describe day-to-day variability in physical activity in a single week, according to sociodemographic variables, in mid-aged Australian ...adults.
Methods
Data were from participants in the How Areas in Brisbane Influence HealTh and AcTivity (HABITAT) study who took part in a 2014 sub-study (
N
= 612; Mean age 60.6 SD 6.9; range 48-73). Participants wore a triaxial accelerometer (ActiGraph wGT3X-BT) on their non-dominant wrist for seven days, and data were expressed as acceleration in gravitational equivalent units (1 m
g
= 0.001 g). These were, used to estimate daily acceleration (during waking hours) and daily time spent in moderate-vigorous physical activity (MVPA, defined as ≥ 100m
g
). Coefficient of variation (calculated as standard deviation/mean of acceleration and MVPA across the seven measurement days * 100%) was used to describe day-to-day variability.
Results
Average values for both acceleration (24.1-24.8 m
g
/day) and MVPA (75.9-79.7 mins/day) were consistent across days of the week, suggesting little day-to-day variability (at the group level). However, over seven days, average
individual
day-to-day variability in acceleration was 18.8% (SD 9.3%; range 3.4-87.7%) and in MVPA was 35.4% (SD 15.6%; range 7.3-124.6%), indicating considerable day-to-day variability in some participants. While blue collar workers had the highest average acceleration (28.6 m
g
/day) and MVPA (102.5 mins/day), their day-to-day variability was low (18.3% for acceleration and 31.9% for MVPA). In contrast, variability in acceleration was highest in men, those in professional occupations and those with high income; and variability in MVPA was higher in men than in women.
Conclusion
Results show group-level estimates of average acceleration and MVPA in a single week conceal considerable day-to-day variation in how mid-age Australians accumulate their acceleration and MVPA on a daily basis. Overall, there was no clear relationship between overall volume of activity and variability. Future studies with larger sample sizes and longitudinal data are needed to build on the findings from this study and increase the generalisability of these findings to other population groups.
Chronic inflammation is independently associated with the incidence and progression of chronic disease. Exercise has been found to reduce chronic inflammation, however the role of exercise intensity ...(work rate) is unknown. This review aimed to determine the pooled effect of higher- compared to lower-intensity aerobic and resistance exercise on chronic inflammation in adults.
Systematic review and meta-analysis.
Five electronic databases were searched. Intervention trials that assessed the effect of ≥2 different exercise intensities on peripheral markers of chronic inflammation c-reactive protein (CRP), interleukin (IL)-6, tumour necrosis factor (TNF)-α and IL-10 in adults were included. Random-effect meta-analyses were conducted to calculate the mean difference in change scores between groups effect size (ES). Sub-group analyses were performed to explore the influence of age, chronic disease, body mass index and intervention duration on inflammation heterogeneity.
Of 3952 studies identified, 27 were included. There were no significant effects of exercise intensity on IL-6 (ES=-0.039, 95%CI=-0.353–0.275; p=0.806), TNF-α (ES=0.296, 95%CI=-0.184–0.777; p=0.227) and IL-10 (ES=0.007, 95%CI=-0.904–0.919; p=0.987). A significant pooled ES was observed for higher- versus lower-intensity exercise on CRP concentrations, in studies of middle-aged adults (ES=-0.412, 95%CI=-0.821– -0.004, p=0.048) or interventions >9 weeks in duration (ES=-0.520, 95%CI=-0.882–-0.159, p=0.005).
Exercise intensity did not influence chronic inflammatory response. However, sub-analyses suggest that higher-intensity training may be more efficacious than lower-intensity for middle-aged adults, or when longer duration interventions are implemented (>9 weeks), in the most commonly-reported analyte (CRP).
Are physical activity (PA) and body mass index (BMI) associated with irregular periods and heavy menstrual bleeding (HMB) in Australian women?
Overweight and obese women have higher odds of both ...irregular periods and HMB than underweight/normal-weight women, but high levels of PA reduce the odds of HMB.
Most studies on relationships between PA and menstrual problems have focused on female athletes, but there have been few population-based studies.
Prospective cohort study, 10618 participants in the Australian Longitudinal Study of Women's Health (ALSWH) who completed mailed surveys in 1996, with follow-ups in 2000, 2003, 2006, 2009, 2012, and 2015.
Participants were aged 22 to 27 in 2000. They were asked to report their PA levels and the frequency of irregular periods and HMB in each survey. BMI was calculated at every survey from self-reported weight and height. Generalised estimating equation population-averaged model analyses were conducted to calculate odds ratios (OR) and 95% confidence intervals (95% CIs).
At age 22 to 27 years, the prevalence of irregular periods was 19.4%. This remained stable over 15 years. There were no associations between PA and irregular periods. Overweight and obese women had higher odds of irregular periods overweight: OR 1.08, (95% CI 1.00-1.17); obese: OR 1.29, (95%CI 1.18-1.41) than women who were underweight/normal weight.The prevalence of HMB at age 22-27 years was 15.9%; this doubled over 15 years. Women who were highly active had 10% lower odds of HMB than women who reported no PA OR 0.90, (95%CI 0.82-0.98). Overweight and obese women had higher odds of HMB overweight: OR 1.15, (95%CI 1.07-1.23); obese: OR 1.37, (95%CI 1.26-1.49) than women who were underweight/normal weight. Among obese women, high levels of PA were associated with 19% OR 0.81, (95%CI 0.68-0.97) reduction in the odds of HMB.
Data collected in the ALSWH are self-reported, which may be subject to recall bias. Reverse causation, due to menstrual problems impacting PA, is possible although sensitivity analyses suggest this is unlikely to have affected the results. Other conditions, e.g., polycystic ovary syndrome, for which no or incomplete data were available, could have affected the results.
Intervention studies are needed to assess the effect of increasing PA in women with HMB, but these preliminary findings suggest that promoting PA could be an affordable and feasible strategy for reducing HMB in young adult women.
The ALSWH is funded by the Australian Government. Funding for these analyses was provided by a University of Queensland (UQ) International Postgraduate Research Scholarship and a UQ International Development Fellowship. The authors declare no conflicts of interest.
N/A.
Abstract
BACKGROUND
In the context of increasing rates of overweight and obesity in young adult women, and the increasing numbers of women seeking help for fertility problems, it is important to ...understand whether physical activity (PA) could help with management of reproductive health problems, with or without weight loss.
OBJECTIVE AND RATIONALE
The primary aim of this systematic review and meta-analysis was to assess the effects of PA on selected reproductive health outcomes in young adult women, in order to inform best practice advice for women in terms of promoting fertility and reproductive health in young adulthood.
SEARCH METHODS
An electronic search of PubMed, EMBASE, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, Web of Science, SportDiscus, and Cochrane was performed for studies published between January 2000 and May 2018. Keywords and Medical Subject Headings terms related to PA, reproductive health, and weight gain were used. Studies were selected if they were intervention studies, if PA was delivered as part of an intervention to pre-menopausal women, and if any reproductive health outcome was reported. Quality analysis was performed using the Tool for the assEssment of Study qualiTy and reporting in EXercise.
OUTCOMES
Eighteen studies, with a mix of four types of study design (4 randomized controlled trials (RCTs), 11 randomized comparison trials, 2 non-randomized comparison trials, and 1 single-arm clinical trial), were identified. Comparisons included fertility treatment (four studies) and common treatments for women with polycystic ovary syndrome (PCOS) symptoms (nine studies). Pooled analysis of data from three of the four studies with a control group showed higher pregnancy risk ratio (RR) 2.10, 95% CI (1.32, 3.35); three studies and live birth RR 2.11, 95% CI (1.02, 4.39); two studies rates in the intervention groups compared with non-therapy controls. Aggregated data from the fertility treatment comparative studies (i.e. those that compared PA with standard fertility treatment such as clomiphene, gonadotrophins, and/or IVF) showed no significant intervention differences: RR 1.46, 95% CI (0.87, 2.45) for clinical pregnancy (four studies) and RR 1.09, 95% CI (0.56, 2.12) for live births (two studies). Pooled analysis from the comparison trials that used pharmaceutical or dietary treatment for PCOS as comparison showed higher pregnancy rates RR 1.59, 95% CI (1.06, 2.38); five studies and live birth rates RR 2.45, 95% CI (1.24, 4.83); two observations in the PA intervention groups than in the comparison groups. Analysis of other outcomes, such as ovulation rates, menstrual regularity, and conception rates, showed no differences between the PA intervention and comparison groups.
WIDER IMPLICATIONS
There is emerging evidence from RCT that PA may improve pregnancy rates in women with reproductive health problems. Comparative studies indicate that PA intervention may be as effective as other commonly used clinical intervention strategies for improving reproductive health outcomes. While the type, intensity, frequency, and duration of optimal PA intervention, and the role of PA independent of weight loss, remain unclear, these preliminary findings suggest that PA may be an affordable and feasible alternative or complementary therapy to fertility treatments.
Current evidence suggests that excess weight and obesity are important risk factors for urinary incontinence in women. However, limited data exist regarding the relationships among body mass index, ...physical activity, and urinary incontinence in women in their 20s.
This study aimed to (1) compare prevalence rates of urinary incontinence and high body mass index in 2 cohorts of young women, (2) explore associations between changes in body mass index and urinary incontinence using analysis of combined data from the 2 cohorts, and (3) explore the associations between physical activity and urinary incontinence, with adjustment for body mass index.
Data were collected from 2 cohorts of young women in the Australian Longitudinal Study of Women’s Health (n=16,065), born 17 years apart: 1973–1978 (cohort 1) and 1989–1995 (cohort 2). The women in both cohorts completed the surveys at age 18 to 23 years (T1), with follow-up 4 years later (age, 22–27 years; T2). Self-reported urinary incontinence and body mass index were assessed in both surveys. As physical activity was measured using different questions in cohort 1 at T1, self-reported physical activity data were from T2 only. A total of 9 body mass index transition categories (based on body mass index status at baseline and follow-up) and 4 physical activity categories were created to assess multivariate-adjusted prevalence ratios for urinary incontinence at T2, using Poisson regression.
Rates of obesity increased in both cohorts over 4 years, from 6.6%% (95% confidence interval, 6.1–7.2) to 10.4% (95% confidence interval, 9.7–11.0) in cohort 1 and from 11.7% (95% confidence interval, 11.0–12.4) to 19.6% (95% confidence interval, 18.7–20.5) in cohort 2. Compared with women who maintained normal body mass index at T1 and T2, the prevalence ratio for urinary incontinence among those with body mass index >30 at age 22 to 27 years was higher, regardless of body mass index category at age 18 to 23 years (prevalence ratio at T1: 1.39 for normal body mass index 95% confidence interval, 1.1–1.76; 1.44 for overweight 95% confidence interval, 1.27–1.63; and 1.51 for obese 95% confidence interval, 1.36–1.67). In cohort 1, there was no relationship between physical activity and urinary incontinence. However, in cohort 2 there was an inverse dose-response relationship between physical activity and urinary incontinence.
The strong association between obesity and urinary incontinence in young women is a public health concern, given that obesity rates are likely to increase further with age and parity. The potential mitigating effects of physical activity on the obesity-incontinence relationship merit further investigation.
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