Body mass index associated with onset and progression of osteoarthritis of the knee but not of the hip: the Rotterdam Study.

OBJECTIVE: To investigate the relationship between body mass index (BMI) and the incidence and progression of radiological knee as well as of radiological hip osteoarthritis. DESIGN: Cohort study. SETTING: Population based. PARTICIPANTS: 3585 people aged > or =55 years were selected from the Rotterdam Study, on the basis of the availability of radiographs of baseline and follow-up. MAIN OUTCOME MEASURES: Incidence of knee or hip osteoarthritis was defined as minimally grade 2 at follow-up and grade 0 or 1 at baseline. The progression of osteoarthritis was defined as a decrease in joint space width. METHODS: x Rays of the knee and hip at baseline and follow-up (mean follow-up of 6.6 years) were evaluated. BMI was measured at baseline. RESULTS: A high BMI (>27 kg/m(2)) at baseline was associated with incident knee osteoarthritis (odds ratio (OR) 3.3), but not with incident hip osteoarthritis. A high BMI was also associated with progression of knee osteoarthritis (OR 3.2). For the hip, a significant association between progression of osteoarthritis and BMI was not found. CONCLUSION: On the basis of these results, we conclude that BMI is associated with the incidence and progression of knee osteoarthritis. Furthermore, it seems that BMI is not associated with the incidence and progression of hip osteoarthritis.

Influence of hip dysplasia on the development of osteoarthritis of the hip.

BACKGROUND: It has been suggested that in some patients with primary hip osteoarthritis (OA), the disease occurs as a consequence of acetabular dysplasia or hip dysplasia (HD). OBJECTIVE: To carry out a systematic review to investigate the association between acetabular dysplasia and hip OA. METHODS: A database search of Medline, Embase, and the Cochrane library was carried out, and articles that aimed at studying the relationship between HD and hip OA were identified. The methodological quality of the selected studies was assessed using a standardised set of criteria, and a best evidence synthesis was used to summarise the results from the individual studies. RESULTS: Five cohort studies and four case-control studies were included in this review. One cohort study had the correct design to answer the question and was considered to be a high quality study. This study reported a positive association between HD and hip OA. Overall, limited evidence was found for a positive association between HD and hip OA. Most studies included older people. In younger age groups the relation between HD and OA or hip complaints may be much higher. CONCLUSION: The evidence for the influence of HD on the occurrence of hip OA, at age 50-60 or older, is limited.

Influence of obesity on the development of osteoarthritis of the hip: a systematic review.

OBJECTIVE: To evaluate the evidence for the influence of obesity as a risk factor for the occurrence of osteoarthritis (OA) of the hip. METHODS: A bibliographical search of Medline, EMBASE and the Cochrane library until April 2000 was carried out. Articles describing studies of the relationship between obesity and the occurrence of hip OA were selected. The quality of the studies was assessed with a standardized set of criteria. The outcome of the studies was compared with respect to study characteristics and the quality score for the study. A best-evidence synthesis was used to summarize the results of the individual studies. RESULTS: Five longitudinal and seven cross-sectional studies were included in this review. There was no association between outcome and study design or methodological quality. The associations between obesity and hip OA were, however, stronger in studies in which the diagnosis of hip OA was based not only on radiological criteria but also on clinical symptoms. Overall, moderate evidence was found for a positive association between obesity and the occurrence of hip OA, with an odds ratio of approximately 2. CONCLUSION: The evidence for a positive influence of obesity on the development of hip OA is moderate.

Intracranial high-intensity transient signals after homograft or mechanical aortic valve replacement.

OBJECTIVE: Comparison of the occurrence, intensity and rate of high-intensity transient signals (HITS), measured in both middle cerebral arteries by transcranial Doppler ultrasound (TCD) after mechanical or homograft aortic valve implantation. EXPERIMENTAL DESIGN: TCD monitoring was performed by means of a pulsed Doppler ultrasound with two 2 MHz probes, stabilized on the head and directed at the middle cerebral artery. SETTING: Outdoor patients after aortic valve replacement in a university hospital. PATIENTS: The study cohort comprised a random transverse sample of patients and included 20 patients with a mechanical aortic valve and 20 with a homograft aortic valve. Comparisons were made with 20 admitted control patients. INTERVENTIONS: No interventions. MEASURES: No significant number of HITS were expected in the homograft group and a limited number in the mechanical valve group. RESULTS: HITS were detected in more patients after implantation of a mechanical aortic valve prosthesis compared with a homograft aortic valve (16 versus 8, p=0.02). Nevertheless, more patients with a homograft aortic valve showed HITS than the control patients (8 versus 1, p=0.02). The mean number of HITS in the mechanical prosthesis group was higher than in the homograft group (3, range 0-18 versus 13, range 0-70, p<0.05). HITS in patients with mechanical prostheses had a higher amplitude than HITS in patients with homograft aortic valves (p<0.0001). Focal neurological deficit (FND) was diagnosed in 9 patients (mechanical prosthesis 6 versus homograft 3, ns). CONCLUSIONS: HITS commonly occur both in patients with a mechanical aortic valve and in patients with a homograft aortic valve. HITS occur significantly less often, at a lower rate and with a lower intensity in patients with homograft aortic valve compared with patients with a mechanical aortic valve. Future studies should elucidate the nature and prognostic significance of HITS and their relationship with thromboembolic events.