Age-related decline in muscle strength is an important public health issue for older adults. Dietary protein has been associated with maintenance of muscle mass, yet its relation to muscle strength ...remains unclear.
We determined the association of dietary protein (total, animal, and plant) intake, measured by food frequency questionnaire, with change in grip strength over 6 years in 1,746 men and women from the Framingham Offspring cohort.
Mean age at baseline was 58.7 years (range: 29-85), and mean total, animal, and plant protein intakes were 79, 57, and 22 g/d, respectively. Adjusted baseline mean grip strength did not differ across quartiles of energy-adjusted total, animal or protein intake. Greater protein intake, regardless of source, was associated with less decrease in grip strength (all p for trend ≤.05): participants in the lowest quartiles lost 0.17% to 0.27% per year while those in the highest quartiles gained 0.52% to 0.60% per year. In analyses stratified by age, participants aged 60 years or older (n = 646) had similar linear trends on loss of grip strength for total and animal (all p for trend <.03) but not plant protein, while the trends in participants younger than 60 years (n = 896) were not statistically significant.
Higher dietary intakes of total and animal protein were protective against loss of grip strength in community-dwelling adults aged 60 years and older. Increasing intake of protein from these sources may help maintain muscle strength and support prevention of mobility impairment in older adults.
Age-adjusted hip fracture incidence is decreasing in the US. The decrease has been attributed to osteoporosis treatment, but the cause is unknown.
To examine the decrease in hip fracture incidence ...over the past 40 years in the US.
A population-based cohort study using participants in the Framingham Heart Study was conducted. A total of 4918 men and 5634 women were followed up prospectively for the first hip fracture between January 1, 1970, and December 31, 2010. Data were analyzed from May 1, 2019, to May 30, 2020.
Incidence of hip fracture and contemporaneous prevalence of risk factors for hip fractures analyzed with age-period-cohort models.
The study contained more than 105 000 person-years in 10 552 individuals with a gradual shift toward the offspring participants in the 1980s and 1990s. Women represented more than 55% of the study sample over the years. Adjusted for age, the incidence of hip fracture decreased by 4.4% (95% CI, 6.8%-1.9%) per year from 1970 to 2010. Both period associations (P < .001) and birth cohort associations (P < .001) were statistically significant. For example, in persons aged 85 to 89 years, the incidence of hip fracture was 759 per 100 000 person-years in the offspring group compared with 2018 per 100 000 person-years in the original cohort. The decrease in hip fracture incidence was coincident with a decrease in smoking and heavy drinking. Smoking decreased from 38% in the 1970s to 15% in the late 2000s, while heavy drinking decreased from 7.0% to 4.5%. The prevalence of other risk factors for hip fracture, such as underweight (body mass index <18.5), obesity (body mass index >30), and early menopause (age <45 years) were stable over the study period. When persons who never smoked were evaluated, a change in the incidence of -3.2% (95% CI, -6.0% to -0.4%) per year was observed. The difference between the decrease of the entire population and nonsmokers of 1.5% per year was similar to the hazard ratio conferred by smoking (hazard ratio, 1.5; 95% CI, 1.14-1.96).
In this study, individuals born more recently appeared to have a low risk for hip fracture. Reductions in smoking and heavy drinking were the risk factor changes coincident with the observed decrease in hip fracture. Attributing the decrease in hip fracture incidence up to 2010 solely to better treatment is not supported by these data, emphasizing the need to treat patients with osteoporosis while continuing to encourage public health interventions for smoking cessation and heavy drinking.
We examined risk factors for falls among older people according to indoor and outdoor activity at the time of the fall and explored risk factors for seriously injurious falls.
Data came from MOBILIZE ...Boston, a prospective cohort study of 765 community-dwelling women and men, mainly aged 70 years or older. Over 4.3 years, 1737 falls were recorded, along with indoor or outdoor activity at the time of the fall.
Participants with poor baseline health characteristics had elevated rates of indoor falls while transitioning, walking, or not moving. Healthy, active people had elevated rates of outdoor falls during walking and vigorous activity. For instance, participants with fast, rather than normal, gait speed, had a rate ratio of 7.36 (95% confidence interval CI = 2.54, 21.28) for outdoor falls during vigorous activity. The likelihood of a seriously injurious fall also varied by personal characteristics, activity, and location. For example, the odds ratio for serious injury from an outdoor fall while walking outside compared to inside a participant's neighborhood was 3.31 (95% CI = 1.33, 8.23).
Fall prevention programs should be tailored to personal characteristics, activities, and locations.
A systematic review and meta-analysis of population-based epidemiological studies was undertaken to determine the prevalence of foot and ankle pain in middle and old age. Searches were conducted in ...the following electronic databases from inception to October 2010: PubMed, EMBASE, AMED, CINAHL, Cochrane, PEDro, and SportDiscus. Full-text English language articles were included if they used population sample frames, cross-sectional design or analysis, and reported prevalence estimates for foot and/or ankle pain in adults aged 45 years and over. Thirty-four articles from 31 studies involving 75,505 participants provided 529 prevalence estimates based on different case definitions and population strata. Random-effects meta-analyses of studies with comparable case definitions provided pooled prevalence estimates, for frequent foot pain of 24% (95% confidence interval 22-25%; n=3; I(2)=46%) and for frequent ankle pain of 15% (95% confidence interval 13-16%; n=2; I(2)=0). Small sample sizes and low response rates in some studies, together with heterogeneous case definitions, limit confident conclusions on the distribution, subtypes, and impact of foot/ankle pain. Narrative synthesis of evidence from existing studies suggested preponderance in females, an age-related increase in prevalence in women but not men, that the toes/forefoot were the most common anatomical sites of pain, and that moderate disability in an aspect of daily life was reported by two-thirds of cases. This review provides estimates of the community burden of foot and ankle pain in middle and old age. By outlining the scale of this clinical problem, these findings can be used to inform health care planning and provision.
OBJECTIVES: To examine the relationship between gait speed and falls risk.
DESIGN: Longitudinal analysis of the association between gait speed and subsequent falls and analysis of gait speed decline ...as a predictor of future falls.
SETTING: Population‐based cohort study.
PARTICIPANTS: Seven hundred sixty‐three community‐dwelling older adults underwent baseline assessments and were followed for falls; 600 completed an 18‐month follow‐up assessment to determine change in gait speed and were followed for subsequent falls.
MEASUREMENTS: Gait speed was measured during a 4‐m walk, falls data were collected from monthly post‐card calendars, and covariates were collected from in‐home and clinic visits.
RESULTS: There was a U‐shaped relationship between gait speed and falls, with participants with faster (≥1.3 m/s, incident rate ratio (IRR)=2.12, 95% confidence interval (CI)=1.48–3.04) and slower (<0.6 m/s, IRR=1.60, 95% CI=1.06–2.42) gait speeds at higher risk than those with normal gait speeds (1.0–<1.3 m/s). In adjusted analyses, slower gait speeds were associated with greater risk of indoor falls (<0.6 m/s, IRR=2.17, 95% CI=1.33–3.55; 0.6–<1.0 m/s, IRR=1.45, 95% CI=1.08–1.94), and faster gait speed was associated with greater risk of outdoor falls (IRR=2.11, 95% CI=1.40–3.16). A gait speed decline of more than 0.15 m/s per year predicted greater risk of all falls (IRR=1.86, 95% CI=1.15–3.01).
CONCLUSION: There is a nonlinear relationship between gait speed and falls, with a greater risk of outdoor falls in fast walkers and a greater risk of indoor falls in slow walkers.
The impact of dietary protein intake on lower extremity lean mass and strength in community-dwelling adult Americans is not fully understood.
The objective was to determine the associations between ...total protein (TP), animal protein (AP), and plant protein (PP) intakes and lean mass of the legs and quadriceps muscle strength. We further examined whether the associations with quadriceps strength may be explained by lean mass of the legs.
This cross-sectional study included men (n = 1166) and women (n = 1509) from the Framingham Offspring Cohort in Massachusetts. Protein intake in grams per day was measured in either 1995-1998 or 1998-2001. Leg lean mass and isometric quadriceps strength, both in kilograms, were measured in 1996-2001. Multilinear regression models estimated adjusted least squares means of each of the muscle measures by quartile categories of protein intake, adjusting for relevant confounders and covariates.
Mean age was 59 ± 9 y (range: 29-86 y) and TP intake was 80 ± 27 g/d in men and 76 ± 26 g/d in women. In men and women, leg lean mass was higher in participants in the highest quartiles of TP and AP intake compared with those in the lowest quartiles of intake least squares means (kg): TP-17.6 vs. 17.1 in men, P-trend: 0.005, and 11.7 vs. 11.4 in women, P-trend: 0.006; AP-17.6 vs. 17.1 in men, P-trend: 0.002, and 11.7 vs. 11.4 in women, P-trend: 0.003. PP intake was not associated with lean mass in either sex. In men and women, quadriceps strength was higher in participants in the highest quartile of PP intake compared with those in the lowest quartile least squares means (kg): 22.9 vs. 21.7 in men, P-trend: 0.01, and 19.0 vs. 18.2 in women, P-trend: 0.01; this association was no longer significant after adjustment for fruit and vegetable intake (P-trend: 0.06 in men and 0.10 in women). Although no significant association was observed for AP intake in either sex, nonsignificant protective trends were observed for TP intake (P-trend: 0.08 in men and 0.10 in women).
Our findings suggest that maintaining adequate protein intake with age may help preserve muscle mass and strength in adult men and women. Dietary protein types may differentially affect muscle mass and strength. Whether PP is a marker of dietary quality or has a direct effect on muscle strength (independent of lean mass) needs to be further clarified.