Estimation of Muscle Mass in Older Adults Using Deuterated Creatine

Current methods for the quantification of muscle mass are indirect, lack precision, and often rely on expensive equipment that only provides limited (indirect) data on whole body muscle mass. Dual energy X ray absorptiometry has emerged as a potential precise measure of lean mass, easy to use in clinical practice and research. However, it assesses an indirect measurement of total-body skeletal muscle mass and its clinical use for determination of changes in muscle mass may be very limited due to instrumentation availability, particularly in field studies, and cost. Moreover, these methods provide estimates of fat free mass that is not skeletal muscle specific, and are influenced by changes in regional or total body water content.

GlaxoSmithKline (GSK) has developed a novel technique using deuterium labeled creatine dilution for the estimation of muscle mass and has begun clinical evaluation of this muscle-measure in healthy young and older adults.

Mobility disability in acute and chronic settings like the Frailty day Hospital or the rehabilitation units make it difficult to assess muscle mass other than the availability of imaging techniques. Often it is impossible to assess muscle mass due to accessibility and cost of actual techniques. Deuterium labeled creatine (contained in capsules to be swallowed) is an easy procedure to assess muscle mass that could avoid the existing difficulties when using imaging techniques. Capsules containing the deuterium labeled creatine will be administered to participants who will autonomously take them. The subsequent assessment of urinary deuterium dilution will provide the estimate of skeletal muscle mass of the individual.

Primary outcome: Assess muscle mass quantity in older adults using the method of deuterium labeled creatine versus the DXA (Dual Energy X-ray Absorptiometry) total lean mass assessment.

Eligibility Criteria:
Inclusion criteria

Population 1: Community-dwelling older adults:

* Community-dwelling at the time of the assessment
* Ambulatory without human assistance at the time of the assessment
* ADL (activity of daily living)equal to 5 or more at the time of the assessment

Population 2: Older adults recovering after hip fracture surgery:

* Age ≥ 65 at the time of the fracture
* Minimal trauma hip fracture (Diagnosis of closed fracture of the proximal femur and no history of a fall from height higher than standing height (e.g. fall from a roof or a ladder); no history of a high impact fracture (e.g. car accident, skiing)
* Unilateral hip fracture
* Surgical repair of hip fracture
* Surgical intervention taking place within 7 days since admission to the acute care unit.
* Living in the community at the time of the fracture
* Anticipated discharge back to the community
* Ambulatory without human assistance prior to the fracture
* ADL (activity of daily living) equal to 5 or more prior to the fracture

Exclusion criteria

Population 1:Community-dwelling elderly:

* Diagnosis of dementia
* Presence of cognitive impairment (assessed during clinical follow-up using standardized cognitive tools such as MMSE (Mini Mental Status Examination) or MOCA (Montreal Cognitive Assessment), during pre-screening period).
* Inability to provide informed consent
* Presence of severe or uncontrolled neurodegenerative disease like Parkinson's disease, amyotrophic lateral sclerosis or multiple sclerosis
* Presence of an underlying muscle disease other than age-associated muscle waste or disuse atrophy.
* History of stroke with residual hemiplegia
* Diagnosis of a severe medical or psychiatric condition making the participant unlikely to understand or comply with study protocol.
* Diagnosis of malignancy done in the 18 months prior the baseline visit.
* Severe renal failure

Population 2: Older adults recovering from hip fracture:

* Pathological hip fracture
* Diagnosis of dementia
* Presence of cognitive impairment (assessed during clinical follow-up using standardized cognitive tools such as MMSE (Mini Mental Status Examination) or MOCA (Montreal Cognitive Assessment), during prescreening period).
* Peri-operative delirium persisting after day 5 of post-operative period.
* Inability to provide informed consent
* Presence of severe or uncontrolled neurodegenerative disease like Parkinson's disease, amyotrophic lateral sclerosis or multiple sclerosis
* Presence of an underlying muscle disease other than age-associated muscle waste or disuse atrophy.
* History of stroke with residual hemiplegia
* Diagnosis of a severe medical or psychiatric condition making the participant unlikely to understand or comply with study protocol.
* Diagnosis of malignancy done in the 18 months prior the baseline visit.
* Severe renal failure