Some dementia causes reversible

Takaoka, Toyama

Regarding the Oct. 6 editorial, “Future of senile dementia,” Japan’s health authorities need to raise public understanding that dementia, a clinical syndrome of acquired intellectual impairment, could be caused by both reversible and irreversible conditions. Attention to the presence of completely curable causes of dementia might lead to an earlier detection of reversible conditions.

Although many Japanese people still have the false impression that dementia is inevitably progressive and irreversible, there are a variety of reversible cognitive impairments that could be caused by some intracranial disorders as well as metabolic and toxic encephalopathies. For example, subdural hematomas, especially when bilateral, cause dementia, but they could be reversible with surgical drainage. Hydrocephalus, which may cause dementia, incontinence and gait disturbance, could be cured completely with ventricular shunting. Moreover, hypothyroidism and vitamin B1 deficiency, both of which also cause dementia, are completely curable with thyroid hormone replacement and vitamin B1 supplementation respectively.

When it comes to elderly persons, multiple prescribed medications, particularly from multiple clinicians, could increase side effects, including memory impairment, when taken together. It is always important to consider a prescribed medication as a potentially reversible cause of dementia.

It should also be noted that therapy for a theoretically reversible cause may not fully restore intellectual function if the dementia has been present for years before the cause is diagnosed. Moreover, chronic conditions that cause permanent changes of the nervous system, such as neurodegenerative illnesses, cannot be reversed with current medical technologies. Nevertheless, appropriate interventions may halt further deterioration of mental decline, or at least, maximize remaining abilities and prevent the need for premature placement in a nursing home.

Changes in mental function might be an initial sign of dementia. Identifying a variety of treatable causes would enhance the quality of a patient’s life, and decrease the emotional, social and financial burden on a patient’s family.

The opinions expressed in this letter to the editor are the writer’s own and do not necessarily reflect the policies of The Japan Times.

hajime ichiseki, m.d.