Background: The relationship between protein dietary intake, Bone Mass Index (BMI) and bone metabolism is controversial. A hyperproteic diet is linked to increased renal calcium excretion but there is no clear evidence of its relevance in the development of osteoporosis (OP). This study aims to evaluate the relationship between protein diet intake, BMI, parathyroid hormone (PTH) levels and fractures.
Methods: Clinical data collected included: fall occurrence; history of vertebral fractures; total serum protein, albumin, inorganic phosphate, calcium, parathyroid hormone, vitamin D and calcium urinary excretion levels and lumbar densitometry. Descriptive statistics, Mann-Whitney and Spearman correlation were applied for a significance of p<0.05.
Results: 276 subjects were included, 80,8% female, mean age 56,4 years. The most prevalent rheumatic diseases were: rheumatoid arthritis (RA), osteoarthritis (OA), Sjogrens syndrome, systemic lupus erythematosus (SLE). The average BMI was 27,1 kg/m2, higher in patients diagnosed with OA. 32 patients had history of fractures. We found correlation between the occurrence of fractures and female gender, lower T-score at femoral neck and lower total serum protein levels. In subjects over 58 years, we found an association with body percentage and BMI, independent of muscle mass (p<0,05). We also found a relation between higher PTH and higher BMI.
Conclusions: In this population, fractures were commoner in women, with lower BMI and lower serum protein levels. Higher BMI and body fat percentage may be risk factors for fall occurrence in the elderly. Patients that had a lower BMI and reduced body fat content consumed more lean fish and showed a higher intake of milk. High PTH levels were correlated with higher BMI, which is in concordance with new evidence suggesting that overweight and obesity do not protect against OP.
Disclosure: The authors declared no competing interests.