Sleep Behaviors and Progression of Multimorbidity in Middle-Aged and Older Adults: A Prospective Cohort Study From China

Interaction effect between sleep duration and dynapenic abdominal obesity for predicting functional disability: A longitudinal study

OBJECTIVE

To assess the interaction of dynapenic abdominal obesity (DAO) and sleep duration on the risk of functional disability among middle-aged and older Chinese individuals.

METHODS

Data were extracted from the China Health and Retirement Longitudinal Study conducted in 2011, 2013, 2015, 2018, and 2020. A total of 6,343 participants were enrolled in this retrospective cohort study. Sleep duration was obtained through face-to-face interviews. Dynapenia (D) and abdominal obesity (AO) were defined by handgrip strength and waist circumference, respectively. Functional disability was assessed according to activities of daily living scales. Cox proportional hazard models analyzed the interactions of DAO and sleep duration on functional disability.

RESULTS

Over a mean follow-up of 10 years, 3,879 (61.2%) participants reported functional disability. Individuals with short sleep duration and D/AO (appropriate but short: RR = 1.42, 95% CI = 1.10-1.82, too short sleep: RR = 1.54, 95% CI = 1.16-2.06), long sleep duration and D/AO (appropriate but long: RR = 1.61, 95% CI = 1.11-2.33; too long: RR = 1.63, 95% CI = 1.15-2.32), were more likely to develop functional disability than those with normal sleep duration and ND/NAO in the fully adjusted model. The multiplicative interaction between the short sleep group and D/NAO or ND/AO were both significant. Middle-aged individuals and females were more susceptible to the effects of short sleep and DAO, while elderly individuals and males were more susceptible to the effects of long sleep and DAO.

CONCLUSIONS

Short and long sleep durations combined with DAO increase the risk of functional disability. Managing waist circumference and improving grip strength in middle-aged and older adults with abnormal sleep durations may help prevent functional disability.

Mediating roles of activities of daily living and depression on the relationship between sleep quality and health-related quality of life

This study aimed to explore the mediating effects of ADL and depression on the relationship between sleep quality and HRQOL among older people in rural China, while also exploring the moderating impact of loneliness. The study gathered data from a household survey conducted among 1587 Chinese rural older adults (mean age = 73.63 years). The collected data was analyzed using SPSS version 23.0 software (IBM, New York, USA) and the PROCESS macro version 4.0 program. The findings indicated a significant correlation between sleep quality, ADL, depression, loneliness and HRQOL. ADL and depression exhibited a chain mediation effect on the relationship between sleep quality and HRQOL. Notably, the association between sleep quality and HRQOL was entirely mediated by ADL and depression. Additionally, loneliness acted as a moderator in the relationship between ADL and HRQOL. The findings of this study suggest that interventions focusing on sleep quality should prioritize strategies for enhancing older adults' ADL and depression as integral components of promoting older adults' HRQOL.

Ten-Year Stability of an Insomnia Sleeper Phenotype and Its Association With Chronic Conditions

OBJECTIVE

To identify distinct sleep health phenotypes in adults, examine transitions in sleep health phenotypes over time, and subsequently relate these to the risk of chronic conditions.

METHODS

A national sample of adults from the Midlife in the United States study ( N = 3683) provided longitudinal data with two time points (T1: 2004-2006, T2: 2013-2017). Participants self-reported on sleep health (regularity, satisfaction, alertness, efficiency, duration) and the number and type of chronic conditions. Covariates included age, sex, race, education, education, partnered status, number of children, work status, smoking, alcohol, and physical activity.

RESULTS

Latent transition analysis identified four sleep health phenotypes across both time points: good sleepers, insomnia sleepers, weekend catch-up sleepers, and nappers. Between T1 and T2, the majority (77%) maintained their phenotype, with the nappers and insomnia sleepers being the most stable. In fully adjusted models with good sleepers at both time points as the reference, being an insomnia sleeper at either time point was related to having an increased number of total chronic conditions by 28%-81% at T2, adjusting for T1 conditions. Insomnia sleepers at both time points were at 72%-188% higher risk for cardiovascular disease, diabetes, depression, and frailty. Being a napper at any time point related to increased risks for diabetes, cancer, and frailty. Being a weekend catch-up sleeper was not associated with chronic conditions. Those with lower education and unemployed were more likely to be insomnia sleepers; older adults and retirees were more likely to be nappers.

CONCLUSION

Findings indicate a heightened risk of chronic conditions involved in suboptimal sleep health phenotypes, mainly insomnia sleepers.

Determinants of multimorbidity in older adults in Iran: a cross-sectional study using latent class analysis on the Bushehr Elderly Health (BEH) program

BACKGROUND AND OBJECTIVES

Multimorbidity, defined as the presence of two or more long-term health conditions in an individual, is one of the most significant challenges facing health systems worldwide. This study aimed to identify determinants of classes of multimorbidity among older adults in Iran.

RESEARCH DESIGN AND METHODS

In a cross-sectional sample of older adults (aged ≥ 60 years) from the second stage of the Bushehr Elderly Health (BEH) program in southern Iran, latent class analysis (LCA) was used to identify patterns of multimorbidity. Multinomial logistic regression was conducted to investigate factors associated with each multimorbidity class, including age, gender, education, household income, physical activity, smoking status, and polypharmacy.

RESULTS

In 2,426 study participants (mean age 69 years, 52% female), the overall prevalence of multimorbidity was 80.2%. Among those with multimorbidity, 3 latent classes were identified. These comprised: class 1, individuals with a low burden of multisystem disease (56.9%); class 2, individuals with predominantly cardiovascular-metabolic disorders (25.8%) and class 3, individuals with predominantly cognitive and metabolic disorders (17.1%). Compared with men, women were more likely to belong to class 2 (odds ratio [OR] 1.96, 95% confidence interval [CI] 1.52-2.54) and class 3 (OR 4.52, 95% CI 3.22-6.35). Polypharmacy was associated with membership class 2 (OR 3.52, 95% CI: 2.65-4.68) and class 3 (OR 1.84, 95% CI 1.28-2.63). Smoking was associated with membership in class 3 (OR 1.44, 95% CI 1.01-2.08). Individuals with higher education levels (59%) and higher levels of physical activity (39%) were less likely to belong to class 3 (OR 0.41; 95% CI: 0.28-0.62) and to class 2 (OR 0.61; 95% CI: 0.38-0.97), respectively. Those at older age were less likely to belong to class 2 (OR 0.95).

DISCUSSION AND IMPLICATIONS

A large proportion of older adults in Iran have multimorbidity. Female sex, polypharmacy, sedentary lifestyle, and poor education levels were associated with cardiovascular-metabolic multimorbidity and cognitive and metabolic multimorbidity. A greater understanding of the determinants of multimorbidity may lead to strategies to prevent its development.