Anti-dementia drugs may prolong life in Alzheimer's patients

Mary shared the following information based on a report in Family Practice News summarizing a presentation by Dr. Susan Rountree (Baylor College of Medicine) at the International Conference on Alzheimer's Disease.
Citation: Sullivan, M.G. (2008) Antidementia drugs may prolong life in Alzheimer's patients. Family Practice News, 38, pp. 1 & 4.

The purpose of the study was to determine whether currently prescribed anti-dementia drugs have an effect on survival rates among the elderly. Five drugs available during the study were evaluated: tacrine, donepezil, rivastigmine, galantamine, and memantine). The study tracked use of drugs over time and evaluated whether the length of use and type of medication influenced survival.

This was a prospective observational study of 641 patients seen at the Alzheimer's disease and memory disorders center at Baylor College and evaluated annually until death.

The independent variable was "medication persistency" which captured the amount of time the person spend on medication relative to the duration of their illness. Patients were classified into quartiles (on medication for up to 33% of illness; 34-55% of illness; 56-70% of illness; >70% of illness).

The dependent variable was survival.

Co-variates included age, sex, years of education, duration of symptoms, and severity of disease. If the patient was on anti-dementia drugs prior to enrollment, a "pre-progression rate" was calculated.

Findings: Patients who took medications for greater than 70% of the time since their diagnosis (those in the upper quartile) lived an average of three years longer than those in the first quartile. Compared to those in the upper quartile, those in the lower 2 quartiles were more than twice as likely to die.

Take home message: as practitioners, we need to encourage families to view the available medications as positive treatment although they are not a cure.

Food for thought: The current USPSTF notes that there is insufficient evidence to recommend for or against routine screening for Alzheimer's. Would early diagnosis and therefore early treatment improve survival ABOVE that seen in this study when patients were presumable started on meds after presenting with symptoms?