Effect of dietary sources of calcium and protein on hip fractures and falls in older adults in residential care: cluster randomised controlled trial

The BMJ

Oct 2021

DOI: 10.1136/bmj.n2364

Citations:90

Influential Citations:6

Interventional (Human) Studies

Enhanced Details

Methods

Two-year cluster randomised controlled trial in 60 accredited residential aged care facilities in ACT and Victoria, Australia; participants: 7195 permanent residents (mean age 86.0 years; ~68-70% female) living in facilities housing predominantly ambulant residents; vitamin D adequacy maintained via routine supplementation; outcomes analyzed at facility level with mixed effects models.

Intervention

Two additional daily servings of dairy foods (milk, yogurt, and cheese) provided to intervention facilities for 24 months; serving definitions: 250 mL milk, 200 g yogurt, 40 g cheese; fortification of milk with milk powder for use in recipes/beverages; additional dairy foods delivered through meals and snacks, replacing less nutritious options; added calcium ~562 mg/day and protein ~12 g/day, totaling ~1142 mg calcium/day and ~69 g protein/day.

Results

Providing two extra daily servings of dairy foods to older adults in residential care reduced fracture and fall risk. All fractures: HR 0.67 (95% CI 0.48–0.93; P=0.02); hip fractures: HR 0.54 (95% CI 0.35–0.83; P=0.005); falls: HR 0.89 (95% CI 0.78–0.98; P=0.04). Significance for all fractures and hip fractures emerged by five months. All-cause mortality did not differ. Conclusion: increasing calcium and protein intake via regular dairy foods is a feasible, accessible strategy to reduce fractures and falls among aged-care residents and may have public health benefits beyond the setting.

Limitations

Less than half of participants had follow-up longer than 15 months; substantial attrition and replacement of residents; compliance/dietary data collected in a subset; biomarker analyses available only in a small subgroup; some data not collected for all outcomes; partial blinding of staff and possible awareness of allocation; generalizability may be limited to similar aged-care populations.

Abstract

Abstract Objective To assess the antifracture efficacy and safety of a nutritional intervention in institutionalised older adults replete in vitamin D but with mean intakes of 600 mg/day calcium and <1 g/kg body weight protein/day. Design Two year cluster randomised controlled trial. Setting 60 accredited residential aged care facilities in Australia housing predominantly ambulant residents. Participants 7195 permanent residents (4920 (68%) female; mean age 86.0 (SD 8.2) years). Intervention Facilities were stratified by location and organisation, with 30 facilities randomised to provide residents with additional milk, yoghurt, and cheese that contained 562 (166) mg/day calcium and 12 (6) g/day protein achieving a total intake of 1142 (353) mg calcium/day and 69 (15) g/day protein (1.1 g/kg body weight). The 30 control facilities maintained their usual menus, with residents consuming 700 (247) mg/day calcium and 58 (14) g/day protein (0.9 g/kg body weight). Main outcome measures Group differences in incidence of fractures, falls, and all cause mortality. Results Data from 27 intervention facilities and 29 control facilities were analysed. A total of 324 fractures (135 hip fractures), 4302 falls, and 1974 deaths were observed. The intervention was associated with risk reductions of 33% for all fractures (121 v 203; hazard ratio 0.67, 95% confidence interval 0.48 to 0.93; P=0.02), 46% for hip fractures (42 v 93; 0.54, 0.35 to 0.83; P=0.005), and 11% for falls (1879 v 2423; 0.89, 0.78 to 0.98; P=0.04). The risk reduction for hip fractures and falls achieved significance at five months (P=0.02) and three months (P=0.004), respectively. Mortality was unchanged (900 v 1074; hazard ratio 1.01, 0.43 to 3.08). Conclusions Improving calcium and protein intakes by using dairy foods is a readily accessible intervention that reduces the risk of falls and fractures commonly occurring in aged care residents. Trial registration Australian New Zealand Clinical Trials Registry ACTRN12613000228785. show less