Adiposity is increased among high-functioning, non-ambulatory patients with spinal muscular atrophy.
The relationship between body composition and function in spinal muscular atrophy (SMA) is poorly understood. 53 subjects with SMA were stratified by type and Hammersmith functional motor scale, expanded score into three cohorts: low-functioning non-ambulatory (type 2 with Hammersmith score < 12, n=19), high-functioning non-ambulatory (type 2 with Hammersmith score > or = 12 or non-ambulatory type 3, n=17), and Ambulatory (n=17). Lean and fat mass was estimated using dual-energy X-ray absorptiometry. Anthropometric data was incorporated to measure fat-free (lean mass in kg/stature in m(2)) and fat (fat mass in kg/stature in m(2)) mass indices, the latter compared to published age and sex norms. Feeding dysfunction among type 2 subjects was assessed by questionnaire. Fat mass index was increased in the high-functioning non-ambulatory cohort (10.4+/-4.5) compared with both the ambulatory (7.2+/-2.1, P=0.013) and low-functioning non-ambulatory (7.6+/-3.1, P=0.040) cohorts. 12 of 17 subjects (71%) in the high-functioning non-ambulatory cohort had fat mass index > 85th percentile for age and gender (connoting "at risk of overweight") versus 9 of 19 subjects (47%) in the low-functioning non-ambulatory cohort and 8 of 17 ambulatory subjects (47%). Despite differences in clinical function, a similar proportion of low functioning (7/18, 39%) and high functioning (2/7, 29%) type 2 subjects reported swallowing or feeding dysfunction. Non-ambulatory patients with relatively high clinical function may be at particular risk of excess adiposity, perhaps reflecting access to excess calories despite relative immobility, emphasizing the importance of individualized nutritional management in SMA.
Sproule
Douglas M
DM
Division of Pediatric Neurosciences, Department of Neurology, SMA Clinical Research Center, Columbia University Medical Center, New York, NY 10032-3791, USA. dsproule@neuro.columbia.edu
Montes
Jacqueline
J
Dunaway
Sally
S
Montgomery
Megan
M
Battista
Vanessa
V
Koenigsberger
Dorcas
D
Martens
Bill
B
Shen
Wei
W
Punyanitya
Mark
M
Benton
Maryjane
M
Butler
Hailly
H
Caracciolo
Jayson
J
Mercuri
Eugenio
E
Finkel
Richard
R
Darras
Basil
B
De Vivo
Darryl C
DC
Kaufmann
Petra
P
D015502:Absorptiometry, Photon / Q000379:methods; D050154:Adiposity / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000886:Anthropometry / Q000379:methods; D001823:Body Composition / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003680:Deglutition Disorders / Q000209:etiology; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D009134:Muscular Atrophy, Spinal / Q000145:classification / Q000150:complications*; D050177:Overweight / Q000209:etiology; D012129:Respiratory Function Tests / Q000379:methods; D055815:Young Adult