Carin E. Dugowson

Diet and rheumatoid arthritis in women : A possible protective effect of fish consumption

&NA; Some researchers have hypothesized that omega‐3 fatty acids, found primarily in fish oils, may protect against the development of rheumatoid arthritis. We conducted a population‐based case‐control study in women, comparing 324 incident rheumatoid arthritis cases with 1,245 controls. We used a food frequency questionnaire to ascertain diet during a 1‐year period 5 years before a reference date (first physician visit for joint symptoms). Consumption of broiled or baked fish, but not of other types of fish, was associated with a decreased risk of rheumatoid arthritis. The adjusted odds ratios (OR) for 1‐<2 servings and ≥2 servings of broiled or baked fish per week, compared with <1 serving, were 0.78 [95% confidence interval (CI) = 0.53–1.14] and 0.57 (95% CI = 0.35–0.93). Other analyses showed associations with protein as a percentage of calories (adjusted OR for the top quartile as compared with the bottom quartile = 0.65; 95% CI = 0.46–0.94) and total calories (adjusted OR for the top quartile = 1.62; 95% CI = 1.15–2.28). The associations with broiled or baked fish, protein, and calories became stronger when we restricted our analysis to cases positive for rheumatoid factor. These results support the hypothesis that omega‐3 fatty acids may help prevent rheumatoid arthritis.

Does pregnancy provide vaccine‐like protection against rheumatoid arthritis?

OBJECTIVE Previous studies have evaluated the correlation between rheumatoid arthritis (RA) risk and pregnancy history, with conflicting results. Fetal cells acquired during pregnancy provide a potential explanation for modulation of RA risk by pregnancy. The present study was undertaken to examine the effect of parity on RA risk. METHODS We examined parity and RA risk using results from a population-based prospective study in Seattle, Washington and the surrounding area and compared women who were recently diagnosed as having RA (n = 310) with controls (n = 1,418). We also evaluated the distribution of parity in cases according to HLA genotype. RESULTS We found a significant reduction of RA risk associated with parity (relative risk [RR] 0.61 [95% confidence interval 0.43-0.86], P = 0.005). RA risk reduction in parous women was strongest among those who were younger. Most striking was that RA risk reduction correlated with the time that had elapsed since the last time a woman had given birth. RA risk was lowest among women whose last birth occurred 1-5 years previously (RR 0.29), with risk reduction lessening progressively as the time since the last birth increased (for those 5-15 years since last birth, RR 0.51; for those >15 years, RR 0.76), compared with nulliparous women (P for trend = 0.007). No correlation was observed between RA risk and either age at the time a woman first gave birth or a womans total number of births. Among cases with the highest genetic risk of RA (i.e., those with 2 copies of RA-associated HLA alleles), a significant underrepresentation of parous women versus nulliparous women was observed (P = 0.02). CONCLUSION In the present study, there was a significantly lower risk of RA in parous women that was strongly correlated with the time elapsed since a woman had last given birth. While the explanation for our findings is not known, HLA-disparate fetal microchimerism can persist many years after a birth and could confer temporary protection against RA.

Nontraumatic femur fracture in an oligomenorrheic athlete

Exercise-associated amenorrhea is the cessation of menses in a woman following onset of training or an increase in training intensity. Its physiologic basis is characterized by consistently low levels of gonadotropin and ovarian hormones, but the underlying cause of this phenomenon is unknown. Although osteopenia has been described in amenorrheic women athletes, it has been primarily a laboratory diagnosis. Several recent studies have described a significantly lower bone mineral density (BMD) in the lumbar spine of amenorrheic athletes. Marcus et al. also reported an increased number of metatarsal and tibial stress fractures in a group of amenorrheic women. We report here the first case of a nontraumatic femur fracture in an amenorrheic athlete. A 32-yr-old white female, with four prior fibular stress fractures, suffered a left femoral shaft fracture during the 13th mile of a half-marathon. The fracture was successfully internally fixed. Biochemical studies showed no metabolic abnormality. Bone mineral density of the lumbar spine, femoral neck, tibia, and fibula were below the mean for both eumenorrheic and amenorrheic female athletes. Exercise-associated amenorrhea is a medical problem that may have serious implications for both competitive and high-intensity recreational female athletes.

A multi-centre, blinded, randomised, placebo-controlled, laboratory-based study of MQX-503, a novel topical gel formulation of nitroglycerine, in patients with Raynaud phenomenon

Objective MQX-503 is a novel nitroglycerine preparation designed to absorb quickly and allow local vasodilatation in the skin. We examined the efficacy and tolerability of this medication in Raynaud phenomenon (RP) in a laboratory-based study. Methods In this multi-centre, double-blind, randomised, placebo-controlled, cross-over study, subjects were treated with 0.5% or 1.25% nitroglycerine or placebo gel. Subjects received each dose twice in a randomised order. Each study session consisted of baseline laser Doppler measurements, study gel application and 5 min of cold chamber exposure (−20°C). Blood flow (BF) was measured at the end of exposure and for the next 120 min at set intervals. Other outcome measures included achievement of baseline BF; the time to achieve 50% and 70% baseline skin temperature (ST); and pain, tingling and numbness scores. Results 37 subjects completed 214 treatment periods. Time to achieve baseline BF was significantly shorter in the two treated groups (HR=1.77 and 2.02 for 0.5% and 1.25% vs placebo, respectively). The proportion of subjects achieving baseline BF was 45.8% for placebo, 66.2% for 0.5% and 69% for 1.25% (p=0.01 and p=0.002 for 0.5% and 1.25% vs placebo, respectively). No meaningful differences were seen in ST or pain/numbness/tingling scores. Treatment was well tolerated with no serious adverse events. Conclusions Treatment with MQX-503 caused a significant improvement in skin BF compared with placebo. Data from this proof of concept study suggest benefit of MQX-503 in subjects with RP.

Adverse Pregnancy Outcomes and Risk of Subsequent Rheumatoid Arthritis

Pregnancy and reproductive outcomes have been associated with altered risk of some autoimmune diseases, including rheumatoid arthritis (RA). We sought to determine whether prior pregnancy resulting in a low birth weight (LBW) infant or preterm birth is associated with a risk of subsequent RA in the mother.

53 – Rheumatoid Arthritis

Rheumatoid arthritis (RA) is the most common of the inflammatory arthritides and, combined with its multiple systemic effects and complications of therapy, causes significant morbidity. As with many autoimmune diseases, women are at greater risk of developing RA than men . Beyond gender differences in incidence rates, there is also a complex relationship among rheumatoid arthritis, female sex hormones, and reproductive status in modulating both the risks for disease and its clinical course in women. Genetic susceptibility also plays a role, with increased disease risk and severity in certain Human Leukocyte Antigen haplotypes. These factors make understanding the epidemiology of RA particularly relevant in discussion of womens health issues. RA can be a fatal illness. One study found mortality was increased twofold in people with RA, resulting in a decrease of seven to ten years in lifespan. Mortality directly due to RA represented only 10% of the deaths and was from causes such as respiratory failure or cervical spine instability.