Alzheimers and CJD

Alzheimer's and CJD
Michael Greger
16 June 1996

If indeed a form of Bovine Spongiform Encephalopathy (BSE) exists in the United States, one might expect to see a rise in the number of cases of Creutzfeldt-Jakob disease (CJD). CJD, however, is not a reportable illness in this country (Holman, 1995). Because the Centers for Disease Control (CDC) does not actively monitor the disease (Altman, 1996d) a rise similar to the one in Britain could be missed (Altman, 1996d).
Already, a number of U. S. CJD clusters have been found. In the largest known U. S. outbreak of sporadic cases to date(Flannery, 1996) a five-fold expected rate was found to be associated with cheese consumption in Pennsylvania's Lehigh Valley (Little, 1993) A striking increase in CJD was also reported in Florida (Berger, 1994) and there is an anecdotal report of an cluster in Oregon (Boule, 1996). An analysis of death certificates in a number of states, though, showed an overall stable and typical CJD incidence rate from 1979 to 1993 (World, 1996). To track the disease, the CDC has just initiated a four-state study of death certificates (Altman, 1996a), but since it is considered well known that death-certificate diagnoses are not always accurate (Davanpour, 1993) the survey may not provide an accurate assessment.

The true prevalence of prion diseases in this or any other country remains a mystery (Harrison, 1991). Compounding the uncertainty, autopsies are rarely performed on atypical dementias (Harrison, 1991), because medical professionals fear infection (Altman, 1996a). The officially reported rate in this country is less than 1 case in a million people per year (World, 1996). An informal survey of neuropathologists, however, registered a theoretical range of 2-12% of all dementias as actually CJD (Harrison, 1991). And hundreds of thousands of Americans suffer from severe dementias every year (Brayne, 1994; United, 1995). Two other studies average about a 3% CJD rate among dementia patients (Mahendra, 1987; Wade, 1987). A preliminary 1989 University of Pennsylvania study showed that 5% of patients diagnosed with dementia were actually dying from Creutzfeldt-Jakob disease (Boller, 1989). It would seem CJD is seriously underdiagnosed at present (Harrison, 1991).

The most common misdiagnosis of CJD is Alzheimer's disease (Harrison, 1991). CJD was even described by our government's top CJD researcher (Wlazelek, 1990a) as "Alzheimer's in fast forward (Wlazelek, 1990b)." The symptoms and pathology of both diseases overlap (Brown, 1989). There can be spongy changes in Alzheimer's, for example, and senile plaques in CJD (Brown, 1989). The causes may overlap as well; epidemiological evidence suggests that people eating meat more than four times a week for a prolonged period have a three times higher chance of suffering a dementia than long-time vegetarians (Giem, 1993), although this result may be confounded by vascular factors (Van Duijn, 1996).

Paul Brown, medical director for the U.S. Public Health Service (Gruzen, 1996), said that the brains of the young people who died from the new CJD variant in Britain even look like Alzheimer's brains (Hager, 1996). Stanley Prusinger, the scientist who coined the term prion, speculates Alzheimer's may in fact turn out to be a prion disease (Prusiner, 1984). In younger victims the disease could look like multiple sclerosis or a severe viral infection, according to Alzheimer's expert Gareth Roberts (Brain, 1996).

An estimated two to three million Americans are afflicted by Alzheimer's (Scully, 1993); it is the fourth leading cause of death among the elderly in the U.S (Perry, 1995). Twenty percent or more of people clinically diagnosed with Alzheimer's disease are found at autopsy to not have had Alzheimer's at all (McKhann, 1984). At Yale, out of 46 patients clinically diagnosed with Alzheimer's, 6 were proven to be CJD at autopsy (Manuelidis, 1989). In another post-mortem study 3 out of 12 "Alzheimer" patients actually died from a spongiform encephalopathy (Teixeira, 1995).

Carleton Gajdusek, who was awarded a Nobel Prize for his work with prion diseases (Manuelidis, 1985), estimates that 1% of people showing up in Alzheimer clinics actually have CJD (Folstein, 1983). That means that hundreds of people (Hoyert, 1996; United, 1995) may already be dying from mad cow disease each year in the United States.

Source: http://www.mad-cow.org/Alzheimer_cjd.html