Linear and non-linear associations between physical activity, body composition and multimorbidity over 10 years among community-dwelling older adults

Body mass index and multimorbidity risk: A systematic review and dose-response meta-analysis

OBJECTIVE

To verify the dose-response relationship between body mass index (BMI) and multimorbidity risk.

METHODS

PubMed, CINAHL, and Embase were systematically studied until January 25, 2023. Original articles on BMI and multimorbidity risk were included. Random effects model and dose-response meta-analysis were used to estimate the pooled odds ratio (OR) with 95 % confidence interval (CI). Subgroup analysis was performed to explore potential heterogeneity.

RESULTS

A total of 43 studies involving 969,130 patients (94,978 with multimorbidity) were involved in the meta-analysis. In the longitudinal studies, the pooled results showed that, compared to being a normal BMI, being overweight was much similar with 1.32 times possibility of getting multimorbidity; in persons with obesity the risk was 1.93 times higher; and the risk decreased 0.80 times among underweight persons. Additionally, obesity was 1.75 times as likely to be multimorbidity than those non-obese persons. In the cross-sectional studies, the pooled results demonstrated that persons with overweight and obesity had a 1.38-fold and 2.38-fold risk for multimorbidity, respectively; and the risk decreased 0.90 times among underweight persons compared to those with normal BMI. Besides, obese people are 1.89 times more likely to have multimorbidity than non-obese people. Dose response analysis found the linear connection between BMI and multimorbidity risk (Pnon-linearity=0.762), that for each 1 kg/m2 and 5 kg/m2 increase in BMI, the multimorbidity risk increased by 6 % and 35 %, respectively.

CONCLUSIONS

Multimorbidity increased linearly with an increase in BMI. Clinicians should pay attention to persons with abnormal weight, to help them achieve normal BMI.

Impacts of active mobility on individual health mediated by physical activities

Active mobility, encompassing walking and cycling for transportation, is a potential solution to health issues arising from inadequate physical activity in modern society. However, the extent of active mobility's impact on individual physical activity levels, and its association with health as mediated by physical activities, is not fully quantified. This study aims to clarify the direct relationship between active mobility usage and individual health, as well as the indirect relationship mediated by physical activity, with a focus on varying levels of physical activity intensity. Utilizing data from the 2017 U.S. National Household Travel Survey (NHTS), we employed Poisson regression to predict active mobility usage based on socio-demographic and household socio-economic characteristics. A Structural Equation Model (SEM) was then used to investigate the direct and indirect effects of active mobility on individual health, mediated by physical activity. We further segmented individuals according to their intensity of physical activity to examine how such effect differs between different levels of physical activity. The study demonstrates that active mobility usage positively correlates with both the amount and intensity of physical activity. The effect of active mobility on individual health includes a direct positive effect (29% for intensity, 67.7% for amount) and an indirect effect mediated by physical activity (71% for intensity, 32.3% for amount). Notably, the mediation effect of active mobility on health is more substantial in the context of vigorous physical activities compared to light or moderate activities. Our findings reveal a significant positive influence of active mobility on individual health, encompassing both direct and indirect effects mediated by physical activities. These results quantitatively underscore the health benefits of active mobility and suggest the importance of promoting active mobility as a strategy to improve public health.

Association of possible sarcopenia with major chronic diseases and multimorbidity among middle-aged and older adults: Findings from a national cross-sectional study in China

AIM

This study investigated the prevalence of possible sarcopenia (PSA) in a large sample of middle-aged and older adults, and determined the association between PSA, major chronic diseases and the number of chronic diseases.

METHODS

A total of 14 917 adults aged ≥40 years were included in the analysis. The handgrip strength and the five-time chair stand test were used to assess PSA. The participants' major chronic diseases were divided into 14 categories. Four categories were created based on the participants' number of chronic illnesses: 0, 1, 2 and ≥3.

RESULTS

The present study found an overall prevalence of PSA of 23.6% among Chinese middle-aged and older adults aged ≥40 years, with the risk increasing with advancing age. PSA was significantly associated with most categories of chronic diseases and multimorbidity. The closely independent associations were obtained for stroke; emotional, nervous or psychiatric problems; chronic lung disease, asthma, heart disease, hypertension and arthritis or rheumatism. Compared with participants with 0 chronic disease, those with two or more chronic diseases had higher odds for PSA. However, the association between PSA and the number of chronic diseases varied in different sex and age groups.

CONCLUSIONS

The findings suggest that PSA is associated with major chronic diseases among middle-aged and older adults. People with two or more chronic diseases have a greater likelihood of PSA compared with those without chronic diseases, and the association between PSA and the number of chronic diseases largely depended on sex and age. Geriatr Gerontol Int 2023; 23: 925-931.

Linear and non-linear relationships between sulfur dioxide and semen quality: A longitudinal study in Anhui, China

Existing evidence indicates that ambient air pollutants pose a threat to human semen quality; however, these findings are sparse and controversial. Besides, their non-linear dose-response relationship has not yet been well investigated. This study aimed to explore the linear and non-linear associations of gaseous air pollutants exposure with semen quality based on a large longitudinal cohort. A total of 15,112 males (with 28,267 semen tests) from the Anhui prospective assisted reproduction cohort were analyzed. Individual air pollutants exposure before semen tests in four exposure windows (i.e., 0-9, 10-14, 70-90, and 0-90 days) were estimated by inverse distance weighting interpolation. Linear mixed-effects models, cubic spline analysis and piecewise regression were used to test the potential linear and non-linear dose-response relationships. Ambient SO₂ exposure was negatively associated with all semen quality parameters (all p values < 0.05), except for the progressive motility in the 0-90 and 70-90 days exposure windows. There were 'J' or 'U' shaped dose-response relationships of ambient SO₂ exposure with total sperm count, progressive motility, total motility, progressively motile sperm count, and total motile sperm count (p values for non-linearity < 0.05), but not sperm concentration. Piecewise regression analysis also indicated a negative association of SO₂ exposure with semen quality only when SO₂ exposure was below the cut-off points identified by cubic spline analyses, which were all smaller than 40 μg/m³, the 2021 updated WHO air quality guideline level for SO₂ exposure. Overall, we found that SO₂ exposure was negatively associated with semen quality. Ambient SO₂ exposure could reach the maximum hazardous dose even below the WHO air quality guideline level for SO₂ exposure, suggesting a refinement to the current guideline.

Physical Activity and Multimorbidity Among Community-Dwelling Older Adults: A Systematic Review With Meta-Analysis

OBJECTIVE

This study evaluated the relationship between physical activity (PA) and multimorbidity in community-dwelling older adults.

DATA SOURCE

A systematic review and meta-analysis in the following databases: Pubmed, Lilacs, Scielo, Web of Science, Scopus, and AgeLine.

STUDY INCLUSION AND EXCLUSION CRITERIA

It included observational studies investigating the association between physical activity and multimorbidity, with older adults, published until May 2021. Studies with institutionalized individuals or that assessed specific diseases were excluded.

DATA EXTRACTION

Two reviewers independently extracted the studies based on previous inclusion and exclusion criteria, started by selecting titles, followed by abstracts and full-text reading.

DATA SYNTHESIS

Meta-analysis results were reported as Odds Ratio (OR) with a 95% confidence interval using R language. The Newcastle Ottawa scale was used to assess the quality of the studies.

RESULTS

Fifteen studies were included in the systematic review, from which 12 reported an inverse association between physical activity and multimorbidity. In the meta-analysis, from over 77 000 older adults, there was an inverse association between physical activity and multimorbidity [OR: .81; 95% CI: .73-.89]. We found significant results only for men in the analysis by sex.

CONCLUSIONS

Low levels of physical activity were associated with a higher risk of multimorbidity in older adults. It is expected that public policies will be conducted aimed at the practice of physical activity among older adults.

Muscular strength and skeletal muscle mass in 511 physically independent older women aged 60-88 years

Although one-repetition maximum (1RM) and lean soft tissue (LST) are the most common measures to assess muscular strength and skeletal muscle mass in older adults, reference data is still missing. Therefore, the present study aimed to produce reference values for the 1RM tests and LST in physically independent older women. Furthermore, the effect of age and body segment on these outcomes was examined. Five hundred and eleven older women aged 60-88 years participated in the present study. The 1RM tests were performed on chest press, leg extension, and preacher curl exercises. Dual-energy X-ray absorptiometry exams were used to determine total and segmental LST. The 1RM and LST average values: chest press = 44.0 ± 11.1 kg, leg extension = 48.8 ± 11.8 kg, preacher curl = 21.6 ± 5.4 kg; trunk LST = 19.0 ± 2.7 kg, lower-limbs LST = 12.5 ± 1.9 kg, upper-limbs LST = 4.0 ± 0.7 kg, appendicular LST = 16.6 ± 2.6, total LST = 38.5 ± 5.2 kg. The age-related declines in 1RM chest press and leg extension were higher than in preacher curl. The present study provides reference values for 1RM of different body segments and total and segmental LST in older women. In addition, our results revealed a reduction of muscular strength and LST with increasing age, and the magnitude of the age-related strength reduction depends on the body segment analyzed.