Rheumatoid arthritis and vascular dementia: do they have common pathogenetic mechanisms

Central nervous system involvement is uncommon in patients with rheumatoid arthritis (RA), and the incidence of cerebrovascullitis (CV) ranges from 1% to 8%. It seems to affect only patients with seropositive RA (it shows a close relationship with RF titres), and may appear as part of a systemic manifestation of vasculitis or (less frequently) only involve the brain. It is mainly found in women aged >50 years with RA long-standing seropositive, and usually presents with polymorphic symptoms of headache, seizures and changes in mental status. Patients may have focal signs such as hemiplegia, partial epilepsy, cranial nerve involvement, or visual field loss, or diffuse manifestations denoting encephalitis, such as altered consciousness, confusion, and cognitive impairment or dementia. The clinical alterations surely reflect the extent of the underlying lesionsThe factors involved in the pathophysiology of the disease include endothelial cell antibodies, tumour necrosis factor (TNF), and anti-phospholipid antibodies. Perinuclear anti-neutrophil cytoplasmic antibodies have been found in 29% of patients with rheumatoid CV, thus suggesting that they may play a pathogenic role, and HLA DRB1 has also been encountered. The diagnosis is based on cerebrospinal fluid and imaging studies, but funduscopy should be used to rule out papilledema before performing a lumbar puncture. Cerebral MRI reveals a strong signal in the white matter and may show signal abnormalities in cortical regions or focal cortical atrophy. Although a definite diagnosis requires a cerebral and leptomeningeal biopsy, this is rarely used and its indications are poorly standardised.