Dietary protein intake and risk of osteoporotic hip fracture in elderly residents of Utah.
The role of protein intake in osteoporosis is unclear. In a case-control study in Utah (n = 2501), increasing level of protein intake was associated with a decreased risk of hip fracture in men and women 50-69 years of age but not in those 70-89 years of age. Protein intake may be important for optimal bone health.


BACKGROUND
Protein is an important component of bone, but the role of dietary protein intake in osteoporosis and fracture risk remains controversial.


METHODS
The role of dietary protein intake in osteoporotic hip fracture was evaluated in a statewide case-control study in Utah. Patients, 50-89 years of age, with hip fracture (cases) were ascertained through surveillance of 18 Utah hospitals during 1997-2001. Age- and gender-matched controls were randomly selected. Participants were interviewed in their place of residence, and diet was assessed using a picture-sort food frequency questionnaire previously reported to give a useful measure of usual dietary intake in the elderly Utah population. The association between protein intake and risk of hip fracture was examined across quartiles of protein intake and stratified by age group for 1167 cases (831 women, 336 men) and 1334 controls (885 women, 449 men).


RESULTS
In logistic regression analyses that controlled for gender, body mass index, smoking status, alcohol use, calcium, vitamin D, potassium, physical activity, and estrogen use in women, the odds ratios (OR) of hip fracture decreased across increasing quartiles of total protein intake for participants 50-69 years of age (OR: 1.0 [reference]; 0.51 [95% CI: 0.30-0.87]; 0.53 [0.31-0.89]; 0.35 [0.21-0.59]; p < 0.001). No similar associations were observed among participants 70-89 years of age. Results from analyses stratified by low and high calcium and potassium intake did not differ appreciably from the results presented above.


CONCLUSIONS
Higher total protein intake was associated with a reduced risk of hip fracture in men and women 50-69 years of age but not in men and women 70-89 years of age. The association between dietary protein intake and risk of hip fracture may be modified by age. Our study supports the hypothesis that adequate dietary protein is important for optimal bone health in the elderly 50-69 years of age.
Department of Nutrition and Food Sciences, Utah State University, Logan, Utah 84322-4450, USA.
Heidi J
HJ
Wengreen
Ronald G
RG
Munger
Nancy A
NA
West
D Richard
DR
Cutler
Christopher D
CD
Corcoran
Jianjun
J
Zhang
Nancy E
NE
Sassano
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001205:Ascorbic Acid; D015992:Body Mass Index; D001842:Bone and Bones / Q000502:physiology*; D002136:Calcium, Dietary / Q000008:administration & dosage; D016022:Case-Control Studies; D004032:Diet; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D006620:Hip Fractures / Q000453:epidemiology* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D010024:Osteoporosis / Q000453:epidemiology* / Q000378:metabolism; D011188:Potassium / Q000008:administration & dosage; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking; D014589:Utah / Q000453:epidemiology; D014807:Vitamin D / Q000008:administration & dosage
D002136:Calcium, Dietary; D004044:Dietary Proteins; D014807:Vitamin D; D001205:Ascorbic Acid; D011188:Potassium