Analysis of the relationship of insulin-like growth factor-1 to the growth velocity and feeding of healthy infants.

CONTEXT: Infancy is the fastest growth period in a child's development after birth, but little is known about hormonal regulation mechanism for the growth and development of this period. OBJECTIVE: The objective of this study is to analyze the trend of serum IGF-1 levels in healthy infants and the relationship of IGF-1 to the growth velocity and feeding method of infants. DESIGN: Population-based birth cohort study. SETTING: The study was conducted in the Third Hospital of Peking University. PARTICIPANTS: Study participants were 484 healthy infants, all of whom were full-term and appropriate for gestational age (238 boys and 246 girls). INTERVENTIONS: Interventions were anthropometrical measurements, feeding methods recorded every 1 to 2 months and serum samples (2, 4, 6, 8, 10,12 months). MAIN OUTCOME MEASURES: Height, weight, feeding methods and serum IGF-1 were the main outcome measures. RESULTS: Serum IGF-1 levels decreased in the following 2 months in boys but in females levels remained relatively high between 2 to 3 months after birth and then started to decrease. It reached the lowest point at Months 7-8, and was on a slow rise in both male infants and female infants thereafter. Serum IGF-1 levels were significantly higher in female infants [112.65 ng/ml (CI 91.82, 133.89)] than in male infants [74.38 ng/ml (CI 53.14, 95.61)] at early infancy. Infants fed with human milk had lower serum IGF-1 levels than infants fed with formula milk or human milk plus formula milk (66.94 ± 45.85 ng/ml, 72.56 ± 36.55 ng/ml, 79.89 ± 51.79 ng/ml, respectively; P = 0.019). IGF-1 levels were positively correlated to the growth velocity of body length (P<0.01). CONCLUSION: This study provides the trend for IGF-1 levels at infancy. It is highly possible that IGF-1 plays an important role in the regulation and control of length increases in infants, and feeding method influences serum IGF-1 levels.

Has the incidence of deep vein thrombosis in patients undergoing total hip/knee arthroplasty changed over time? A systematic review of randomized controlled trials.

BACKGROUND: There is a perception in the orthopaedic and thromboembolism community that the incidence of deep vein thrombosis (DVT) has decreased in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA). OBJECTIVES: To assess the incidence of DVT with warfarin thromboprophylaxis over time in patients undergoing elective TKA or THA. METHODS: The MEDLINE, EMBASE, and Cochrane Library databases were searched to October 2006, supplemented by a manual search of reference lists. Two reviewers independently extracted data on study characteristics, quality and the frequency of total, symptomatic and proximal DVT. RESULTS: Fourteen studies (4,423 patients) were included. Total and proximal DVT after TKA declined over time (r=-0.75, p=0.031; r=-0.86, p=0.007 respectively). Total and proximal DVT after THA did not change. The risk of developing DVT after TKA was significantly higher than after THA (OR 1.85, 95% CI 1.6-2.14; p<0.0001). The risk of developing symptomatic DVT after THA was significantly higher than after TKA (OR 2.18, 95% CI 1.11-4.27; p=0.012). CONCLUSIONS: The incidence of DVT in patients undergoing elective TKA appears to have declined in patients receiving warfarin thromboprophylaxis.