Nursing home residents are in high risk of vitamin D deficiency, which negatively affects bone health. Vitamin D and calcium supplements have shown to increase bone density and reduce fracture risk and may affect daily physical functioning. Therefore, The Danish Health Authority recommends all nursing home residents a daily supplement of 20 µg vitamin D and 800-1000 mg calcium. However, adherence to the recommendation is low.

The present project hypothesizes that this low adherence results in a high number of residents with a deficient or insufficient vitamin D status, and that daily physical functioning can be improved or maintained by an improved adherence to the recommendation.

Background: Residents in nursing homes belong to one of the high-risk groups when it comes to vitamin D deficiency, which is associated with increased risk of osteoporosis, muscle weakness and generally decreased physical functioning and frailty. Therefore, the Danish Health Authority recommends that all residents in nursing homes receive a daily supplement of 20 µg of vitamin D in addition to 800-1000 mg of calcium. Some systematic reviews and meta-analyses find that daily supplementation of 20 µg of vitamin D can improve physical functioning and muscle strength among older adults, whereas others do not find an effect. However, most studies are performed in non-institutionalized older adults.

An online survey conducted in May 2020 has revealed that the recommendation of giving residents in nursing homes a daily supplement of 20 µg vitamin D and 800-1000 mg calcium is not routine clinical practice in Denmark. The Danish Health Authority highlights The Model for Improvement as a tool to use when working with evidence-based practice within prevention and health promotion in the municipalities.

Objectives:

• To increase use of the recommended supplements with vitamin D and calcium among residents at nursing homes using The Model for Improvement as a methodological tool.
• To investigate the effect of improved vitamin D and calcium supplement use on vitamin D status and daily physical functioning among residents at nursing homes.

Hypotheses:

• Vitamin D status among residents at nursing homes are low and the majority can be defined as vitamin D insufficient.
• Vitamin D status and daily physical functioning of the residents are positively affected by an improved implementation of the recommendation.

Design and Methods: The project has a quasi-experimental design without control groups. It estimates the causal impact of The Model for Improvement on implementing the specific recommendation in a realistic setting at the nursing homes.

The study includes the following endpoints related to the older adults at the nursing homes evaluated before and after the intervention:

• Number of residents at the participating nursing homes taking supplementation of ≥20 µg of vitamin D and/or ≥800 mg of calcium ≥5 days/week.
• Number of residents at the participating nursing homes classified as having an insufficient and deficient vitamin D status (serum 25-hydroxyvitamin D (25(OH)D <50 nmol/L and <25 nmol/L, respectively)
• Mean daily physical functioning measured as muscle strength, 30-s chair-stand test, and a timed-up-and-go test.

Inclusion Criteria:

• Being a resident at the participating nursing homes
• Understand and speak Danish in order to understand the study procedures
• Be able to give informed consent

Exclusion Criteria:

• Having kidney diseases
• Receiving medication which may induce adverse effects in combination with vitamin D and/or calcium supplements
• Being terminally ill
• Declared incompetent