Impact of health maintenance organizations and fee‐for‐service on health care utilization among people with systemic lupus erythematosus

Objective

To compare health care utilization in people with systemic lupus erythematosus (SLE) in health maintenance organizations (HMOs) and fee‐for‐service (FFS).

Methods

A structured survey was administered to a cohort of 982 people with SLE who were assembled between 2002 and early 2005. A total of 2,656 person‐years of observation were completed by the end of 2005. In each year, respondents reported their health care utilization and whether they had HMO or FFS coverage. We compared health care utilization of those in HMOs and FFS, with and without adjustment for socioeconomic, demographic, and health characteristics using repeated‐measures regression techniques.

Results

Compared with people with SLE who were in FFS, those in HMOs were younger (3.3 years), received a diagnosis at an earlier age (3.6 years), had slightly less disease activity (0.4 on a 10‐point scale), were more likely to be nonwhite (8.8%), were less likely to be below the poverty line (7.8%), and were less likely to have public insurance (29.7%). The 2 groups did not differ in other characteristics. On an unadjusted basis, subjects with SLE in HMOs had significantly fewer physician visits (3.1; 95% confidence interval [95% CI] 1.7, 4.5) and were less likely to report one or more outpatient surgical visits (6.3%; 95% CI 2.5, 10.0), and hospital admissions (5.5%; 95% CI 1.7, 9.3) than those in FFS. Adjustment reduced the differences in physician visits (2.3; 95% CI 1.1, 3.5), outpatient surgical rates (4.4%; 95% CI 0.6, 8.1), and hospital admission rates (4.0%, 95% CI 0.4, 7.7).

Conclusion

Subjects with SLE in HMOs utilized substantially less ambulatory care and were less likely to have outpatient surgery and hospital admissions than those in FFS; the effects were not completely explained by socioeconomic, demographic, and health characteristics.

     

Amebic liver abscess: MR imaging

Hepatic magnetic resonance (MR) imaging was performed in 12 patients with 13 amebic liver abscesses. While no specific image or intensity pattern was noted, most lesions were round or oval with smooth, well-defined margins; had decreased signal intensity compared with that of liver parenchyma on T1-weighted images and increased signal intensity on T2-weighted images; and had prominent, often multiple rims of variable signal intensity. Signal homogeneity within the abscess was present more often on T1- than on T2-weighted images. Diaphragmatic disruption was seen in two cases on coronal MR images. An amebic empyema was differentiable from sympathetic pleural effusions by its hyperintensity on both T1- and T2-weighted images. In patients who also underwent computed tomography (CT) or ultrasonography (US), no lesion was missed with any modality, and except for shape, no consistent features were found among images obtained with the different modalities. The data suggest that CT, US, and MR imaging are comparably effective in the detection of amebic abscess.     

Regulation of anti–cyclic citrullinated peptide antibodies in rheumatoid arthritis: Contrasting effects of HLA–DR3 and the shared epitope alleles

Objective

To examine the association between HLA–DRB1 alleles and the production of anti–cyclic citrullinated peptide (anti‐CCP) and rheumatoid factor (RF) autoantibodies in patients with rheumatoid arthritis (RA).

Methods

We studied 1,723 Caucasian RA patients enrolled in the North American Rheumatoid Arthritis Consortium (NARAC) family cohort and the Study of New Onset Rheumatoid Arthritis (SONORA) cohort. All patients were tested for anti‐CCP antibodies (by enzyme‐linked immunosorbent assay), RF (by nephelometry), and HLA–DR genotype (by polymerase chain reaction and sequence‐specific oligonucleotide hybridization).

Results

When controlled for the presence of RF, anti‐CCP positivity was strongly associated with the HLA–DRB1 shared epitope (SE). In RF+ patients, the presence of the SE was very significantly associated with anti‐CCP positivity, with an odds ratio (OR) of 5.8 and a 95% confidence interval (95% CI) of 4.1–8.3. This relationship was also seen in RF– patients (OR 3.1 [95% CI 1.8–5.3]). In contrast, RF positivity was not significantly associated with presence of the SE independently of anti‐CCP antibodies. Strikingly, HLA–DRB1*03 was strongly associated with reduced anti‐CCP titers, even after controlling for the presence of the SE and restricting the analysis to anti‐CCP+ patients. HLA–DR3 was also associated with anti‐CCP– RA in our population.

Conclusion

The HLA–DRB1 SE is strongly associated with the production of anti‐CCP antibodies, but not RF. In contrast, HLA–DR3 alleles are associated with anti‐CCP– disease and with lower levels of anti‐CCP antibodies, even when controlling for the SE. These data emphasize the complexity of the genetic effects of the major histocompatibility complex on the RA phenotype.

     

A chloroquine elution technique for platelet serology

The authors describe a prototype elution method employing chloroquine, a quinoline derivative, to elute IgG antibodies from the platelet surface. This chloroquine elution technique is relatively easy to perform and is effective in the removal of alloantibodies from the platelet surface. Eluted alloantibody was immunologically active once the chloroquine was removed from the eluate. The major advantage of this technique is that serologic testing of platelets after elution is possible, as 50 percent of the platelets remain after exposure to hypertonic acid chloroquine solution. Antigens on the platelet surface maintained their antigenicity subsequent to treatment, although measurable reductions in PIA1 reactivity occur. The elution technique was also successful in removing IgG from the platelet surface in patients with diseases involving elevated levels of platelet-associated IgG.     

Electrical activity of the ovine jejunum and changes due to disturbances

Spike potential activity of the jejunum was recorded from chronically implanted electrodes in conscious sheep. The activity was summed at 20-sec intervals before, during, and after induction of diarrhea, small-bowel obstruction, and after nerve section. Sheep on a normal diet regimen exhibited migrating myoelectric complexes at a frequency of 18/24 hr. These complexes displayed irregular and regular activities which occupied 67% of the recording time. A common pattern observed during the manipulations was disorganization of the motor profile. The normal pattern was replaced by continuous spiking activity followed in many cases by total quiescence. After vagotomy the complexes still occurred but the duration of irregular spiking activity was decreased. These experiments suggest that the migrating myoelectric complex acts as a regulating factor and suggests that the ratio of irregular to regular activity is dependent on the influence of extrinsic nerves.