Square-stepping exercise and fall risk factors in older adults: a single-blind, randomized controlled trial

BACKGROUND: Decreased fitness of the lower extremities is a potentially modifiable fall risk factor. This study aimed to compare two exercise programs--square-stepping exercise (SSE), which is a low-cost indoor program, and walking--for improving the fitness of the lower extremities. METHODS: We randomly allocated 68 community-dwelling older adults (age 65-74 years) to either the SSE or walking group (W group). During the 12-week regimen, the SSE group participated in 70-minute exercise sessions conducted twice a week at a local health center, and the W group participated in outdoor supervised walking sessions conducted weekly. The W group was instructed to increase the number of daily steps. Prior to and after the program, we obtained information on 11 physical performance tests for known fall risk factors and 3 self-reported scales. The fall incidence was followed-up for 8 months. RESULTS: At 12 weeks postregimen, significant differences were observed between the two exercise groups with respect to leg power (1 item), balance (2 items), agility (2 items), reaction time (2 items), and a self-reported scale (1 item); the SSE group demonstrated a marked improvement in the above-mentioned items with Group x Time interactions. Significant time effects were observed in the tests involving chair stands, functional reach, and standing up from a lying-down position without Group x Time interactions. During the follow-up period, the fall rates per person-year in the SSE and W groups were 23.4% and 33.3%, respectively (p =.31). CONCLUSION: Although further studies are required, SSE is apparently more effective than walking in reducing fall risk factors, and it appears that it may be recommended as a health promotion exercise in older adults.     

The severity of individual obstruction events is related to increased mortality rate in severe obstructive sleep apnea

Obstructive sleep apnea (OSA) is linked to an increased mortality rate. However, the severity of individual obstruction events is rarely considered quantitatively in clinical practice. We hypothesized that OSA with especially severe obstruction events would predispose a patient to greater health risks than OSA with a similar apnea–hypopnea index (AHI), but lower severity of individual events. This hypothesis was tested in a follow‐up (198.2 ± 24.7 months) of a population of 1068 men referred for ambulatory polygraphic recording due to suspected OSA. The recordings were analysed according to the guidelines of the American Academy of Sleep Medicine. Furthermore, a novel obstruction severity parameter was determined; this was defined as the product of duration of the individual obstruction event and area of the related desaturation event. Patients treated with continuous positive airway pressure (CPAP) were omitted. We identified 125 deceased patients from our original population and for 113 of these a matching alive patient with similar AHI, age, body mass index (BMI), smoking habits and follow‐up time could be found. The deceased patients with severe OSA (based on conventional AHI) showed higher obstruction severity values than their AHI‐matched alive controls. Based on the multivariate logistic regression analysis, obstruction severity was the only parameter which was related statistically significantly to mortality in the severe OSA category. Furthermore, 59% of all deceased patients and 83% of those who had severe OSA displayed higher obstruction severity than the AHI‐matched alive counterparts. To conclude, the obstruction severity parameter provided valuable prognostic information supplementing AHI. The obstruction severity parameter might improve recognition of the patients with the highest risk.     

The mediating role of C-reactive protein and handgrip strength between obesity and walking limitation

OBJECTIVES: To study the association between different obesity indicators and walking limitation and to examine the role of C‐reactive protein (CRP) and handgrip strength in that association. DESIGN: A cross‐sectional, population‐based study. SETTING: The Health 2000 Survey with a representative sample of the Finnish population. PARTICIPANTS: Subjects aged 55 and older with complete data on body composition, CRP, handgrip strength, and walking limitation (N=2,208). MEASUREMENTS: Body composition, anthropometrics, CRP, medical conditions, handgrip strength, and maximal walking speed were measured in the health examination. Walking limitation was defined as maximal walking speed less than 1.2 m/s or difficulty walking half a kilometer. RESULTS: The two highest quartiles of body fat percentage and CRP and the two lowest quartiles of handgrip strength were all significantly associated with greater risk of walking limitation when chronic diseases and other covariates were taken into account. In addition, high CRP and low handgrip strength partially explained the association between high body fat percentage and walking limitation, but the risk of walking limitation remained significantly greater in persons in the two highest quartiles than in those in the lowest quartile of body fat percentage (odds ratio (OR)=1.75, 95% confidence interval (CI)=1.19–2.57 and OR=2.80, 95% CI 1.89–4.16). The prevalence of walking limitation was much higher in persons who simultaneously had high body fat percentage and low handgrip strength (61%) than in those with a combination of low body fat percentage and high handgrip strength (7%). Using body mass index and waist circumference as indicators of obesity yielded similar results as body fat percentage. CONCLUSION: Low‐grade inflammation and muscle strength may partially mediate the association between obesity and walking limitation. Longitudinal studies and intervention trials are needed to verify this pathway.     

Environmental facilitators for outdoor walking and development of walking difficulty in community-dwelling older adults

Older adults who report environmental barriers in their neighborhood have a higher risk for walking difficulty. However, environmental facilitators that protect against walking difficulty are not well known. The objective of this study was to identify the effect of environmental facilitators for outdoor walking on development of walking difficulty in community-dwelling older people. This was a prospective study with a 3.5-year follow-up time on 261 community-dwelling people aged 75–81 years, who at baseline were able to walk 0.5 km without difficulty. Environmental facilitators for outdoor walking were self-reported with standardized questionnaires, including having features in one’s home which make it easy to access the outdoors, having a park or other green area within a walking distance from home, having outdoor recreational facilities within a walking distance from home, having features in the nearby environment, which are attractive for outdoor activities, and perceiving the surrounding environment or facilities nearby as motivating factors for physical activity. Self-reported difficulty in walking 0.5 km was assessed every 6 months. Of the participants, 46 % developed walking difficulty during the follow-up. Having a park or other green area within a walking distance from home was the most frequently reported facilitator. Environmental facilitators decreased the risk for development of walking difficulty, hazard ratio per item 0.86, (95 % confidence interval 0.73–1.02). The results indicate that the mobility of older community-dwelling people may be promoted with outdoor recreational facilities that are easy to access and located within a walking distance from home.     

Do mobility,cognitive functioning,and depressive symptoms mediate the association between social activity and mortality risk among older men and women?

Social activity and health correlate in old age, but less is known about what explains this association. The aim of this study was to investigate whether mobility, cognitive functioning, and depressive symptoms mediate the association between social activity and mortality risk, or whether they alternatively should be considered as prerequisites for social activity in older Finnish men and women. In 1988, 406 men and 775 women aged 65–84 years took part in face-to-face interviews about their health, socioeconomic status, and social activities. Confirmatory factor analyses were used to form latent variables describing collective and productive social activity. Latent variable models were used to investigate the possible pathways among social activity, mobility, cognitive functioning, depressive symptoms, and mortality risk. In the 21-year follow-up, 89 % of men and 81 % of women had died. Collective and productive social activity correlated with a lower risk for mortality among men and women. Part of the association between social activity and mortality was mediated by mobility. Cognitive functioning and depressive symptoms were not mediators in the association. Instead, good cognitive functioning and having less depressive symptoms were prerequisites for participating in collective social activity among men and women. Among men, good cognitive functioning, and among women, good cognitive functioning and having less depressive symptoms were prerequisites for productive social activity. The health-enhancing influences of social activity may be partly explained by better mobility among persons who are socially active. Moreover, social activity may maintain mobility and thus decreases mortality risk, as many social activities also include physical activity. Better cognitive functioning and having less depressive symptoms should be considered as prerequisites for participating in social activities.