Changes in sleep duration associated with retirement transitions: The role of naps

The effect of retirement on health behaviors

This paper analyzes the effect of retirement on health behaviors using three nationally representative U.S. datasets. Findings show a decrease in drinking at the intensive margin, particularly for males. Individuals change their composition of exercise behaviors upon retirement, with varying effects of retirement depending on exercise intensity and gender. Dining patterns also change, with changes in eating out among men and more time spent on food preparation. Finally, although retirement increases time spent watching TV and movies as well as time spent sleeping, it reduces overall sedentary time.

A systematic review of evidence on employment transitions and weight change by gender in ageing populations

Background

Becoming unemployed is associated with poorer health, including weight gain. Middle- and older-age adults are a growing segment of workforces globally, but they are also more vulnerable to changes to employment status, especially during economic shocks. Expected workforce exits over the next decade may exacerbate both the obesity epidemic and the economic burden of obesity. This review extends current knowledge on economic correlates of health to assess whether employment transitions impact body weight by sex/gender among middle-aged and older adults.

Methods

Eight bibliometric databases were searched between June and July 2021, supplemented by hand-searches, with no restriction on publication date or country. Longitudinal studies, or reviews, were eligible when examining body weight as a function of employment status change in adults ≥50 years. Data extraction and quality appraisal used predefined criteria; reported findings were analysed by narrative synthesis.

Results

We screened 6,001 unique abstracts and identified 12 articles that met inclusion criteria. All studies examined retirement; of which two also examined job-loss. Overall, studies showed that retirement led to weight gain or no difference in weight change compared to non-retirees; however, reported effects were not consistent for either women or men across studies or for both women and men within a study. Reported effects also differed by occupation: weight gain was more commonly observed among retirees from physical occupations but not among retirees from sedentary occupations. Few studies assessed the role of health behaviours; sleep was the least studied. Most studies were medium quality.

Conclusions

Existing studies do not provide a clear enough picture of how employment transitions affect body weight. Firm conclusions on the impact of employment transitions on weight cannot be made without further high-quality evidence that considers the role of gender, job-type, other health behaviours, and other transitions, like job-loss.

Snoring and napping independently increased the serum uric acid levels and hyperuricemia risk: The Henan Rural Cohort Study

BACKGROUND AND AIMS

Evidence on the association of snoring, daily sleep duration (daytime napping and night sleep duration) with hyperuricemia (HUA) was limited, especially in the resources-poor areas. This study aimed to investigate the independent effect of snoring frequency and daily sleep duration on HUA prevalence in rural Chinese adults.

METHODS AND RESULTS

29,643 participants aged 18-79 years were included in the final cross-sectional analysis from the Henan Rural Cohort Study. Multivariate logistic regression and linear regression models with HUA and serum uric acid (SUA) levels as dependent variables were conducted, respectively. Of the 29,643 included adults, 3498 suffered from HUA. Compared to never snoring, the adjusted odds ratio (OR) and 95% confidence interval (CI) of HUA for rare snoring, occasional snoring, and habitual snoring were 1.35 (1.17, 1.56), 1.30 (1.14, 1.47), and 1.59 (1.47, 1.73), respectively (P for trend <0.001). Compared with no napping, participants who had daytime napping of 61-90 and > 91 min were associated with a 29% and 30% increase in the prevalence of HUA, respectively (P for trend <0.001). But in night sleep duration groups, no significant associations were observed. The positive associations between snoring and HUA were attenuated in people aged ≥65 and people with type 2 diabetes mellitus (both P for interaction <0.05).

CONCLUSION

Habitual snoring or longer daytime napping was independently associated with increased HUA prevalence and SUA levels in rural Chinese adults, which indicates the significance of early intervention and treatment of snoring and longer daytime napping to prevent hyperuricemia.

Factors associated with habitual sleep duration in US adults with hypertension: a cross-sectional study of the 2015-2018 National Health and Nutrition Examination Survey

Background

The relationship between inadequate sleep duration and hypertension risk has been established in the general population, but there is a gap in the literature on predictors of habitual sleep duration in adults with hypertension. This study examined factors associated with habitual sleep duration among adults with hypertension in the United States (US).

Methods

Data of 5660 adults with hypertension were obtained by combining the 2015–2018 cycles of the National Health and Nutrition Examination Survey (NHANES). Survey weighted multinomial logistic regression models were fit to examine factors associated with short (< 7 h) and long (> 9 h) sleep duration with adequate sleep duration (7–9 h) as the reference.

Results

The prevalence of self-reported adequate sleep duration was 65.7%, while short sleep duration was 23.6%, and long sleep duration 10.7%. Short sleep duration (compared to adequate sleep duration) was positively associated with history of seeking help for sleeping difficulties (relative risk ratio [RRR], 1.25; 95% confidence interval [CI], 1.02–1.53), Non-Hispanic Black race/ethnicity (RRR, 2.08; 95% CI, 1.61–2.67), working ≥45 h/week (RRR, 1.81; 95% CI, 1.32–2.48), and negatively associated with older age ≥ 65 years (RRR, 0.63; 95% CI, 0.45–0.91) and female gender (RRR, 0.70; 95% CI, 0.56–0.88). Long sleep duration was positively associated with female gender (RRR, 1.24; 95% CI, 1.001–1.54), chronic kidney disease (RRR, 1.48; 95% CI, 1.14–1.92), moderate depressive symptoms (RRR, 1.62; 95% CI, 1.08–2.44), moderately severe to severe depressive symptoms (RRR, 1.89; 95% CI, 1.05–3.43), being in retirement (RRR, 3.46; 95% CI, 2.18–5.49), and not working due to health reasons (RRR, 4.87; 95% CI, 2.89–8.22) or other reasons (RRR, 3.29; 95% CI, 1.84–5.88).

Conclusion

This population-based study identified factors independently associated with habitual sleep duration in adults with hypertension. These included help-seeking for sleeping difficulty, gender, age, chronic kidney disease, depressive symptoms, race/ethnicity, and employment status. These findings can help in the development of tailored approaches for promoting adequate sleep duration in adults with hypertension.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12465-2.

Age and Sex Differences in the Association of Sleep Duration and Overweight/Obesity among Chinese Participants Age above 45 Years: A Cohort Study

OBJECTIVES

We aimed to evaluate the association between sleep duration and obesity and estimate the attributable risk of sleep in the China Health and Retirement Longitudinal Study surveys (CHARLS).

METHODS

A total of 9061 adults aged 45 years above from CHARLS (2011-2015) were included. The main outcome of this study was incident overweight/obesity specific to general and abdominal obesity. Overweight/obesity was defined as BMI ≥ 23.0 (kg/m2) and BMI≥27.5 (kg/m2), respectively. Abdominal obesity was defined as waist circumference ≥90 cm for men and ≥80 cm for women. Self-reported sleep durations were obtained using a structured questionnaire. We assessed hazard ratios (HRs) and 95% confidence intervals (CIs) as well as the population attributable fraction (PAF) for associations between sleep duration and obesity.

RESULTS

986 and 606 participants were identified as overweight and general obesity respectively, 1253 experienced abdominal obesity events. In multivariable-adjusted models, participants with daytime sleep of 0-30 minutes and more than 30 minutes associated with 30% (HR: 0.70, 95% CI: 0.56-0.87) and 35% (HR: 0.65, 95% CI: 0.55-0.78) decreased incident overweight risk respectively compared to those having no daytime sleep, this association also found among females and middle-aged, not males or elderly. Similarly, 0-30 minutes (HR: 0.68, 95% CI: 0.48-0.96) and more than 30 minutes of daytime sleep (HR: 0.73, 95% CI: 0.59-0.91) were associated with a reduced risk of abdominal obesity, similar results also found among females and middle-aged. Compared with 7-9 hours of nocturnal sleep, people who slept 5-7 hours had a reduced risk of overweight (HR: 0.59, 95% CI=0.47-0.74),but not found in subgroups. The hazard role of long nocturnal sleep for abdominal obesity was only found among elderly (HR: 2.33, 95% CI=1.35-4.04) and males (HR: 2.24, 95% CI=1.17-4.29). Compared with moderate total sleepers (7-9hours/day), participants with short total sleep duration exhibited an elevated risk of overweight (HR: 1.13, 95% CI=1.00-1.28), this also found among middle-aged. The PAF for inadequate total sleep duration (<7 hours/day) was 10.77% for overweight individuals.

CONCLUSIONS

Insufficient sleep duration was associated with an elevated risk of overweight only detected among middle-aged not elderly and other subgroups specific by age. The risks for abdominal obesity were increased for males and middle-aged with long nocturnal sleep. Daytime sleep may significantly reduce the risk of overweight and abdominal obesity in female and middle-aged individuals. The link between sleep duration and obesity requires further study.

Habitual sleep, sleep duration differential, and weight change among adults: Findings from the Wisconsin Sleep Cohort Study

OBJECTIVES

Assess longitudinal associations between diary-measured sleep duration and clinically assessed body mass index (BMI).

DESIGN

Multilevel growth curve analyses examined how within-person changes and between-person differences in habitual sleep duration were associated with BMI trajectories.

SETTING

Sleep diaries across 2-6 consecutive weekday and weekend nights at each data collection point, repeatedly collected at approximate 4-year intervals, for an average of 9.2 (standard deviation [SD] = 3.6) years between 1989 and 2011.

PARTICIPANTS

About 784 participants (47% women) enrolled in the Wisconsin Sleep Cohort Study (mean [SD] age = 51.1 [8.0] years at baseline).

MEASUREMENTS

The outcome variable was BMI (kg/m²). Key predictors were habitual sleep duration (defined as average weekday nighttime sleep duration) and sleep duration differential (defined as the difference between average weekday and average weekend nighttime sleep duration) at each data collection wave.

RESULTS

Men with shorter habitual sleep duration on weekdays had higher BMI than men with longer habitual sleep duration on weekdays (β = -0.90 kg/m²/hour, se = 0.34, p = .008). Participants with larger differentials between weekday and weekend sleep duration experienced more rapid BMI gain over time for both men (β = 0.033 kg/m²/year per hour differential, se = 0.017, p = .044) and women (β = 0.057 kg/m²/year per hour differential, se = 0.027, p = .036).

CONCLUSION

This study suggests that habitual short sleep is associated with higher BMI levels in men and that a larger weekday-weekend sleep differential is associated with increasing BMI trajectories among both men and women in mid-to-late life.

Daytime Napping Duration Is Positively Associated With Risk of Hyperuricemia in a Chinese Population

CONTEXT

Loss of sleep or disturbance of sleep-wake cycles has been related to metabolic impairments. However, few studies have investigated the association between daily sleep duration and hyperuricemia.

OBJECTIVE

We investigated daily sleep duration (daytime napping and nocturnal sleep) with hyperuricemia risk.

METHODS

We cross-sectionally analyzed data from the China Multi-Ethnic Cohort (CMEC), Yunnan region. A total of 22 038 participants aged 30 to 79 years were recruited in 2018. Hyperuricemia was defined as serum uric acid (SUA) above 7.0 mg/dL in men and above 6.0 mg/dL in women. Outcomes were associations between daily sleep duration and hyperuricemia.

RESULTS

We found that the longest daytime napping duration was associated with a higher risk of hyperuricemia in the crude model (odds ratio [OR] [95% CI], 2.22 [1.88-2.61], P < .001) and in a multivariable adjustment model (OR, 1.69; 95% CI, 1.41-2.01, P < .001) after adjusting for demographic, sleep habits, and metabolic risk factors. The association was moderately attenuated with additionally adjusted for serum creatinine (OR, 1.54; 95% CI, 1.28-1.86, P < .001). Longer daytime napping duration was also related to higher risk of hyperuricemia combined with metabolic syndrome (MetS). Respondents in the group with daytime napping duration greater than or equal to 90 minutes presented with a higher risk of hyperuricemia combined with MetS (OR, 1.39; 95% CI, 1.06-1.79; P < .001) in the fully adjusted model. We did not observe any relation between nocturnal sleep duration and risk of hyperuricemia in the study.

CONCLUSION

Longer daytime napping duration (but not nocturnal sleep duration) was independently associated with risk of hyperuricemia in a Chinese population.

Does Work after Retirement Matter? Sleep Features among Workers in the Brazilian Longitudinal Study of Adult Health

A growing number of people keep working after retirement, a phenomenon known as bridge employment. Sleep features, which are related to morbidity and mortality outcomes, are expected to be influenced by bridge employment or permanent retirement. The objective of this study was to analyze sleep duration and quality of bridge employees and permanent retirees compared to nonretired, i.e., active workers, from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Participants (second wave of ELSA-Brasil, 2012–2014) comprised permanently retired (n = 2348), career bridge workers (n = 694), bridge workers in a different place (n = 760), and active workers (n = 6271). The associations of all studied retirement schemes and self-reported sleep quality and duration were estimated through logistic and linear regression analysis. Workers from all studied retirement schemes showed better sleep patterns than active workers. In comparison to active workers, bridge workers who had changed workplace also showed a reduced chance of difficulty falling asleep and too-early awakenings, which were not found among career bridge workers. Bridge employment and permanent retirement were associated with a reduced chance of reporting sleep deficit. Bridge work at a different place rather than staying at the same workplace seems to be favorable for sleep. Further study is needed to explain mechanisms.

Daytime Sleep as Compensation for the Effects of Reduced Nocturnal Sleep on the Incidence of Hypertension: A Cohort Study

PURPOSE

The role of sleep duration in the development of hypertension remains controversial. Little is known about the combined effects of nocturnal and daytime sleep. We assessed the association between total sleep duration and the development of hypertension in middle-aged and elderly Chinese adults.

PATIENTS AND METHODS

Data were obtained from 3 waves of China Health and Retirement Longitudinal Study surveys. Middle-aged and elderly Chinese initially without hypertension were followed biennially from 2011 to 2015. Sleep duration was self-reported. Hypertension was defined as a systolic and/or diastolic blood pressure ≥ 140/90 (mmHg), the current use of anti-hypertensive medications or self-reported hypertension.

RESULTS

Over 31,392 person-years of follow-up, 2682 of 10,176 participants developed hypertension. The multivariable adjusted hazard ratios (HR) (95% confidence intervals, 95% CI) for the development of hypertension between those with 0-30 minutes and ≥30 minutes daytime sleep vs those without daytime sleep were 0.67 (0.58, 0.77), and 0.73 (0.59, 0.92), respectively. The protective role of longer periods of daytime sleep (>30 minutes) varied between different subgroups. Compared with moderate nocturnal sleepers, long nocturnal sleepers (HR: 1.66, 95% CI=1.25-2.21) had an increased risk of hypertension. Compared with moderate nocturnal sleepers without daytime sleep, HRs (95% CI) for hypertension were 0.52 (0.45, 0.59) for short nocturnal sleep plus short daytime sleep and 0.55 (0.49, 0.62) for short nocturnal sleep plus long daytime sleep. People with extremely short (HR: 1.34, 95% CI=1.22-1.48) and long (HR: 1.28, 95% CI=1.13-1.44) combined sleep periods had an increased risk of hypertension. Consistent results were also found in subgroups stratified by age and gender.

CONCLUSION

Both extremely long and short total sleep periods were associated with an increased risk of hypertension. People with short or moderate nocturnal sleep durations, especially short nocturnal sleep duration, can benefit from habitual daytime sleep to prevent hypertension.