Comorbidity clusters in generalized osteoarthritis among female patients: A cross-sectional study

OBJECTIVES

To investigate the prevalence of comorbidities among female patients with generalized osteoarthritis (GOA) in comparison to an age- and sex matched control group. To identify clusters of comorbidities in both groups.

METHODS

An observational, cross-sectional study was conducted. Consecutive female patients with hand and knee osteoarthritis according to the American College of Rheumatology (ACR) classification criteria were invited to participate in the study. A control group of participants without musculoskeletal symptoms, history or evidence of osteoarthritis or inflammatory rheumatic disease were also included. Cardiovascular, obstructive pulmonary, gastrointestinal, endocrine, neurological, malignant diseases and depression were recorded in both groups. In both study groups comorbidity cluster and factor analysis was performed.

RESULTS

The study population included 200 GOA and 200 control participants. The following comorbidities were observed adjusted to Bonferroni correction with a significantly higher prevalence among individuals with GOA: hypertension, uterine leiomyoma, gastroesophageal reflux disease, diverticulosis, upper gastrointestinal tract ulcers, depression, diseases with vertigo (benign paroxysmal positional vertigo and vertebrobasilar insufficiency) and surgery due to otoclerosis. In the GOA group 5 clusters were identified with different comorbidity patterns.

CONCLUSION

We report a high comorbidity rate in GOA. Cluster analysis allowed us to identify different comorbidity subsets for vascular, gastrointestinal and malignant gynaecological disorders. Further research is required to understand the links between GOA and non-musculoskeletal comorbidities.

Felty's syndrome

Felty's syndrome (FS) comprises a triad of rheumatoid arthritis (RA), neutropenia and splenomegaly, occurring in less than 1% of RA patients. Clinically it is characterized by severe joint destruction contrasting with moderate or absent joint inflammation and severe extra-articular disease, including a high frequency of rheumatoid nodules, lymphadenopathy, hepatopathy, vasculitis, leg ulcers, skin pigmentation etc. Recurrent bacterial infections are mostly due to the severe, otherwise unexplained neutropenia. The cause of neutropenia lies in both decreased granulopoiesis and increased peripheral destruction of granulocytes. Recurrent infections may lead to increased mortality. Spontaneous remission of the syndrome also occurs. Over 95% of FS patients are positive for rheumatoid factor (RF), 47-100% are positive for antinuclear antibody (ANA), and 78% of patients have the HLA-DR4*0401 antigen. Some 30% of FS patients have large granular lymphocyte (LGL) expansion. LGL expansion associated with uncomplicated RA is immunogenetically and phenotypically very similar to but clinically different from FS. Neutropenia of FS can be effectively treated with disease-modifying anti-rheumatic drugs (DMARDs), the widest experience being with methotrexate (MTX). Results of treatment with granulocyte colony-stimulating factor (G-CSF) are encouraging, but there is no experience with other biological agents. Splenectomy results in immediate improvement of neutropenia in 80% of the patients, but the rate of infection decreases to a lesser degree.

Ultrasonography after hip arthroplasty

Ultrasonography was performed in 55 patients who had total Charnley hip arthroplasties. Effusions were identified in 19 patients and confirmed in all but 3 by arthrocentesis or at surgery. Aspirations were performed in 5 and demonstrated infection in 2. It is concluded that ultrasound is a valuable noninvasive method for assessing painful hip arthroplasty. It can demonstrate the presence of effusion, which should be aspirated to exclude infection.

Punched-card aid in rheumatological diagnosis

A punched-card diagnostic system is described for use in rheumatological practice. The system is based on pattern recognition and provides a list of both common and rare possible diseases. The system is simple and can be manufactured cheaply, and may be of particular use to family doctors in remote areas of practice. The system has also potential as an educational tool for both undergraduate and postgraduate students of medicine.

Diagnosis of rheumatic disease: a plea for contemplation of the future

In clinical practice the definition of diagnosis is far from clear, since different levels of diagnosis are employed from the symptomatic to the pathological and aetiological. The recent development of computer data bases has important implications for the future, but will require a great deal of thought regarding the nature and quality of the data to be used. Evolution of diagnosis has occurred gradually during the history of medicine. As we see it, computer-assisted data handling will have a profound effect on diagnosis and classification of disease. To meet this challenge we require to define our terms regarding diagnosis of rheumatic disorders. In this paper we comment on the state of the art of diagnosis and classification of rheumatic diseases, and then propose changes to meet the needs of future developments.

Calcium pyrophosphate crystals in intermittent hydrarthrosis

A 49-year-old female presented with intermittent hydrarthrosis affecting the right knee. Numerous calcium pyrophosphate crystals were demonstrated in synovial fluid aspirated from the knee.