Rheumatoid Arthritis and Mortality in End Stage Renal Disease.

OBJECTIVE: To determine whether rheumatoid arthritis (RA) is a risk factor for cardiovascular disease (CVD) events, all-cause mortality and cardiovascular mortality in End Stage Renal Disease (ESRD). METHODS: Cohort study of adult patients with ESRD in the United States Renal Data System (USRDS) with RA and a 5% random sample of those without RA. CVD events, all-cause mortality and cardiovascular mortality were determined in those with RA compared to those without RA using Cox Proportional Hazards modeling. RESULTS: 2,824 subjects, 407 with RA and 2,417 without RA, were included in the analyses. The duration of the study was up to 5 years, depending on mortality and initiation of dialysis. There were no significant differences in CVD events by RA status (n = 311 [76.4% RA] vs. n = 1936 [80.1% without RA], p = 0.09). Subjects with RA had a significantly shorter mean time in months from start of dialysis to an incident CVD event (20.1 ± 12.2 vs. 21.2 ± 14.1, p < 0.01) than those without RA. In multivariable adjusted models, RA was not associated with an increased risk for all-cause mortality (aHR = 1.09, 95%CI 0.94-1.27) or cardiovascular mortality (aHR = 0.95, 95% CI 0.74-1.22) within 5 years. Risk factors for all-cause mortality and cardiovascular mortality in RA included older age and a higher Charlson comorbidity index (CCI). CONCLUSIONS: Clinicians should be aware that persons with RA who develop ESRD incur cardiac events sooner than the general population. However, RA is not an independent risk factor for all-cause or cardiovascular mortality in ESRD.

A Curious Case of Weakness: Antineutrophil Cytoplasmic Antibody-Associated Vasculitis Presenting With Muscle Weakness.

Disease manifestations of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), a small vessel vasculitis with multisystemic effects, include respiratory, renal, nervous, gastrointestinal, and skin implications. Muscle weakness and inflammatory myopathy are rare manifestations of AAV. We report the case of a 77-year-old female with a medical history of hypothyroidism and osteoarthritis who presented with a two-month history of worsening muscle weakness (mainly proximal). She endorsed dysphagia, a 40-lb unintentional weight loss, and persistent sinusitis with middle ear effusions, requiring bilateral tympanostomy. The physical examination was notable for 2/5 muscle strength in her hip flexors and extensors, with 4/5 strength in other extremities. Lower extremity MRI showed diffuse intramuscular edema between fat planes and intramuscular septal regions. Erythrocyte sedimentation rate (70 mm/hr), C-reactive protein (141 mg/L), creatine kinase (690 U/L), and anti-myeloperoxidase (MPO) antibodies (>999 AU/mL) were elevated. A thigh biopsy revealed fibrinoid necrosis of small intramuscular arteries, confluent circumferential granulomatous vessel wall inflammation, and associated mild chronic inflammation, including occasional eosinophils and a few plasma cells. She was diagnosed with MPO-positive AAV. The patient was started on high-dose steroids (prednisone), with a taper on a disease-modifying agent, azathioprine, with significant improvement in symptoms over the next four months and complete resolution at 16-month follow-up. This patient's clinical presentation of predominant lower extremity weakness due to inflammatory myositis is an unusual manifestation of AAV. Clinicians should keep a broad differential diagnosis and consider the possibility of AAV, especially in cases of muscle weakness presenting as inflammatory myositis, in the absence of other clinical manifestations of systemic vasculitis or specific myositis serologies.

End-stage renal disease in patients with rheumatoid arthritis.

OBJECTIVES: To determine the frequency of end-stage renal disease (ESRD) in patients with rheumatoid arthritis (RA), the causes of ESRD, and the treatment of RA in the setting of ESRD. METHODS: Cross-sectional study of RA (N = 3754) and non-RA (N = 326,776) patients in the United States Renal Data System (USRDS) during 2011 (N = 330,530). The epidemiology of ESRD in RA was determined and the etiology of ESRD in patients with and without RA was compared. The frequency of patients with RA with at least one filled prescription for prednisone/prednisolone, a DMARD, and/or a biologic in 2011 was determined. RESULTS: The prevalence of RA with ESRD in the USRDS in 2011 was 1.1%. There were significant differences in age, race, sex, and BMI category between the groups (p < 0.01). Diabetes (33.5%) and hypertension (30.6%) were the most common primary causes of ESRD in patients with RA. Amyloidosis, vasculitis, and analgesic nephropathy combined accounted for less than 10% of cases of ESRD. Prednisone was the most commonly filled medication that could be used to treat RA (45.9% of RA patients). Hydroxychloroquine was the most frequently filled DMARD (13.5%); biologics were uncommon (etanercept 2.5%, adalimumab 1.5%; golimumab, infliximab, anakinra, and abatacept <1%). CONCLUSIONS: The co-occurrence of RA with ESRD was 1.1% in the USRDS by 2011. Physicians should be aware of the critical impact of the comorbidities of diabetes and hypertension in causing ESRD in RA patients. Use of DMARDS other than hydroxychloroquine and biologics to treat RA in the setting of ESRD appears to be infrequent. Further prospective studies of treatment strategies for RA in ESRD are needed.