Plasma Concentrations of Long Chain N-3 Fatty Acids in Early and Mid-Pregnancy and Risk of Early Preterm Birth.

BACKGROUND: Fish oil supplementation has been shown to delay spontaneous delivery, but the levels and clinical significance remain uncertain. We examined the association between plasma fatty acids quantified in pregnancy and subsequent risk of early preterm birth. METHODS: In a case-control design nested in the Danish National Birth Cohort, we identified 376 early preterm cases (<34 gestational weeks, excluding preeclampsia cases) and 348 random controls. Plasma eicosapentaenoic acid plus docosahexaenoic acid (EPA+DHA% of total fatty acids), were measured twice in pregnancy, at gestation weeks 9 and 25 (medians). Odds ratios and 95% confidence intervals (CI's) for associations between EPA+DHA and early preterm risk were estimated by logistic regression, adjusted for the woman's age, height, pre-pregnancy BMI, parity, smoking, and socioeconomic factors. Hypotheses and analytical plan were defined and archived a priori. FINDINGS: Analysis using restricted cubic splines of the mean of 1st and 2nd sample measurements showed a strong and significant non-linear association (p < 0.0001) in which the risk of early preterm birth steeply increased when EPA+DHA concentrations were lower than 2% and flattened out at higher levels. Women in the lowest quintile (EPA+DHA < 1.6%) had 10.27 times (95% confidence interval 6.80-15.79, p < 0.0001) increased risk, and women in the second lowest quintile had 2.86 (95% CI 1.79-4.59, p < 0.0001) times increased risk, when compared to women in the three aggregated highest quintiles (EPA+DHA ≥ 1.8%). INTERPRETATION: Low plasma concentration of EPA and DHA during pregnancy is a strong risk factor for subsequent early preterm birth in Danish women.

Risk of cancer in relatives of patients with myotonic dystrophy: a population-based cohort study.

BACKGROUND AND PURPOSE: Myotonic dystrophies (DM) are autosomal dominantly inherited neuromuscular disorders caused by unstable nucleotide repeat expansions. DM and cancer have been associated, but the pathogenesis behind the association remains unclear. It could relate to derived effects of the DM genotype in which case non-DM relatives of DM patients would not be expected to be at increased risk of cancer. To elucidate this, a population-based cohort study investigating risk of cancer in relatives of DM patients was conducted. METHODS: DM was identified using the National Danish Patient Registry and results of genetic testing. Information on cancer was obtained from the Danish Cancer Registry. A population-based cohort of 5 757 565 individuals with at least one relative was established using the Danish Family Relations Database based on kinship links in the Danish Civil Registration System. Familial aggregation of cancer was evaluated by (incidence) rate ratios (RRs) comparing the rate of cancer amongst relatives of patients with DM from 1977 to 2010 (exposed) with the rate of cancer amongst persons with a relative of the same type but without DM (non-exposed). RESULTS: In first-degree relatives of individuals with DM the adjusted RR of cancer was 0.89 (95% confidence interval 0.71-1.12) overall, and in stratified analyses 0.68 (0.37-1.12) before age 50 and 0.96 (0.74-1.23) at age 50 or older. CONCLUSIONS: The present study does not support an increased risk of cancer in non-DM relatives of DM patients suggesting that cancer and DM are associated through derived effects of the DM genotype.

Continuous passive motion applied to whole joints stimulates chondrocyte biosynthesis of PRG4.

UNLABELLED: Continuous passive motion (CPM) is currently a part of patient rehabilitation regimens after a variety of orthopedic surgical procedures. While CPM can enhance the joint healing process, the direct effects of CPM on cartilage metabolism remain unknown. Recent in vivo and in vitro observations suggest that mechanical stimuli can regulate articular cartilage metabolism of proteoglycan 4 (PRG4), a putative lubricating and chondroprotective molecule found in synovial fluid and at the articular cartilage surface. OBJECTIVES: (1) Determine the topographical variation in intrinsic cartilage PRG4 secretion. (2) Apply a CPM device to whole joints in bioreactors and assess effects of CPM on PRG4 biosynthesis. METHODS: A bioreactor was developed to apply CPM to bovine stifle joints in vitro. Effects of 24h of CPM on PRG4 biosynthesis were determined. RESULTS: PRG4 secretion rate varied markedly over the joint surface. Rehabilitative joint motion applied in the form of CPM regulated PRG4 biosynthesis, in a manner dependent on the duty cycle of cartilage sliding against opposing tissues. Specifically, in certain regions of the femoral condyle that were continuously or intermittently sliding against meniscus and tibial cartilage during CPM, chondrocyte PRG4 synthesis was higher with CPM than without. CONCLUSIONS: Rehabilitative joint motion, applied in the form of CPM, stimulates chondrocyte PRG4 metabolism. The stimulation of PRG4 synthesis is one mechanism by which CPM may benefit cartilage and joint health in post-operative rehabilitation.